Wikiversity enwikiversity https://en.wikiversity.org/wiki/Wikiversity:Main_Page MediaWiki 1.48.0-wmf.3 first-letter Media Special Talk User User talk Wikiversity Wikiversity talk File File talk MediaWiki MediaWiki talk Template Template talk Help Help talk Category Category talk School School talk Portal Portal talk Topic Topic talk Collection Collection talk Draft Draft talk TimedText TimedText talk Module Module talk Event Event talk 4 28 2844893 2844728 2026-11-08T21:05:29Z Jtneill 10242 /* Commons vote about watermarking AI images */ new topic ([[mw:c:Special:MyLanguage/User:JWBTH/CD|CD]]) 2844893 wikitext text/x-wiki {{Wikiversity:Colloquium/Header}} <!-- MESSAGES GO BELOW --> == Paid part-time Administrative Officer position with WikiJournal == [[WikiJournal User Group|WikiJournal]] is an open-access, nonprofit scholarly publisher hosted on Wikiversity. It uses the wiki format to allow authors to write and develop scholarly articles directly online. Submitted articles then undergo formal academic peer review and, when accepted, are published as citable journal articles while remaining freely accessible. WikiJournal is seeking expressions of interest in a new part-time '''Administrative Officer''' position. The officer would support the project's day-to-day organizational work, including: * Setting up and administering a system for tracking contractor hours and issuing payments. * Coordinating the contracting, onboarding, timekeeping and payment of technical editors and other contractors. * Maintaining financial, contractor and administrative records. * Assisting with grant administration, budget tracking and reporting. * Following up on board action items, deadlines and recurring obligations. * Supporting recruitment and other operational tasks as needed. This is a remote, flexibly scheduled contractor role averaging approximately '''6 hours per week'''. Compensation is proposed at '''US$25 per hour''', with up to approximately '''320 hours (US$8,000) available over the year'''. Applicants may be based internationally, although appointment will depend on WikiJournal being able to establish a practical and legally appropriate contracting and payment arrangement in the applicant's country of residence. Relevant experience may include administrative organization, bookkeeping or financial administration, contractor or personnel coordination, nonprofit or grant administration, Wikimedia participation, academic publishing, and open-access work. Applicants are not expected to have experience in every area. For the complete role description and further details, see [[WikiJournal User Group/Administrative officer]]. Those interested should reply in the '''[[Talk:WikiJournal User Group#Call for interest: Administrative Officer|Call for interest: Administrative Officer]]''' discussion by '''30 September 2026''', briefly describing their relevant experience, any connection to WikiJournal or related communities, and their general availability. Expressions of interest received later may still be considered if the position has not been filled. Recommendations of potentially suitable candidates are also welcome. [[User:Mikael Häggström|Mikael Häggström]] ([[User talk:Mikael Häggström|discuss]] • [[Special:Contributions/Mikael Häggström|contribs]]) 20:00, 10 September 2026 (UTC) == Server switch - Your wiki will be read-only for a short time soon == <section begin="server-switch"/><div class="plainlinks"> [[:m:Special:MyLanguage/Tech/Server switch|Read this message in another language]] • [https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FServer+switch&language=&action=page&filter= {{int:please-translate}}] The [[foundation:|Wikimedia Foundation]] will switch the traffic between its data centers. This will make sure that Wikipedia and the other Wikimedia wikis can stay online even after a disaster. All traffic will switch on '''{{#time:j xg|2026-09-23|en}}'''. The switch will start at '''[https://zonestamp.toolforge.org/{{#time:U|2026-09-23T14:00|en}} {{#time:H:i e|2026-09-23T14:00}}]'''. Unfortunately, because of some limitations in [[mw:Special:MyLanguage/Manual:What is MediaWiki?|MediaWiki]], all editing must stop while the switch is made. We apologize for this disruption, and we are working to minimize it in the future. A banner will be displayed on all wikis 30 minutes before this operation happens. This banner will remain visible until the end of the operation. You can contribute to the [https://meta.wikimedia.org/w/index.php?title=Special%3ATranslate&group=Centralnotice-tgroup-read_only_banner&task=view&language=&filter=&action=translate translation or proofreading] of this banner text. '''You will be able to read, but not edit, all wikis for a short period of time.''' * You will not be able to edit for up to an hour on {{#time:l j xg Y|2026-09-23|en}}. * If you try to edit or save during these times, you will see an error message. We hope that no edits will be lost during these minutes, but we can't guarantee it. If you see the error message, then please wait until everything is back to normal. Then you should be able to save your edit. But, we recommend that you make a copy of your changes first, just in case. ''Other effects'': * Background jobs will be slower and some may be dropped. Red links might not be updated as quickly as normal. If you create an article that is already linked somewhere else, the link will stay red longer than usual. Some long-running scripts will have to be stopped. * We expect the code deployments to happen as any other week. However, some case-by-case code freezes could punctually happen if the operation require them afterwards. * [[mw:Special:MyLanguage/GitLab|GitLab]] will be unavailable for about 90 minutes. This project may be postponed if necessary. You can [[wikitech:Switch_Datacenter|read the schedule at wikitech.wikimedia.org]]. Any changes will be announced in the schedule. '''Please share this information with your community.'''</div><section end="server-switch"/> [[m:user:Trizek (WMF)|Trizek (WMF)]] 12:58, 15 September 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Distribution_list/Non-Technical_Village_Pumps_distribution_list&oldid=30513874 --> == Your feedback wanted: Remove ''(Language link added:) and similar'' edits from Special:RecentChanges == ''(Apologies for posting in English. You can help by translating it)'' Hello, I’m Danny from [[:en:w:Wikimedia_Deutschland|Wikimedia Deutschland’s]] [[m:Wikidata_For_Wikimedia_Projects|Wikidata For Wikimedia Projects]] team.<br/> We have been investigating and examining how Wikidata’s use in the [[Special:RecentChanges]] and [[Special:Watchlist]] pages can be made to be more useful, or less ‘noisy’ (fewer edits that have little value to the reader). We are currently exploring to make a change in the volume and the type of Wikidata edits that appear in these pages, and '''we need your feedback''' to help us ensure this is a positive change for the Wikis and won’t disrupt your workflows.<br/> Language links are also known as sitelinks or interlanguage links and describe when a Wikidata item is connected to a Wiki, adding it to the language dropdown tool for other connected Wikis. [[File:Types of Lang Link changes.png|x350px|frame|A variety of "Language Link" edits as seen in the Recent Changes feed]] The request for feedback is whether you support the removal of these language link edits from the Recent Changes and Watchlist feed, or would you oppose such a change and if so, why? Please share you thoughts on the dedicated '''[[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|metawiki Talk page]]'''. Further information about this change: [[m:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|m:Wikidata_For_Wikimedia_Projects/Hide_Language_Link_edits]] Thank you for any participation or feedback you give, -- [[m:User:Danny_Benjafield_(WMDE)|User:Danny Benjafield (WMDE)]] 12:23, 25 September 2026 (UTC) <!-- Message sent by User:Danny Benjafield (WMDE)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=User:Danny_Benjafield_(WMDE)/MassMessage_test_list&oldid=31080985 --> == Wikidata Sitelink changes in Recent Changes and Watchlist == ''(Apologies for cross-posting in English, translating it will help spread the message)'' Editors on group 1 wikis, including Wikiquote, Wikibooks, Wikiversity, Wikivoyage, and Wikisource, will no longer see notifications on [[Special:RecentChanges|Recent Changes]] and [[Special:Watchlist|Watchlist]] when a link to ''another'' language version of a page is added, removed, or changed in its Wikidata item. This change will begin on '''October 5 at 07:00 UTC''' as a two-week trial to reduce high-volume, low-value notifications and make higher-value changes easier to identify. Editors who rely on these notifications should be aware of the change and can share feedback or concerns on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project]] or [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]].<br/>Please reach out if you have any questions, thank you! -- [[User:Danny_Benjafield_(WMDE)|Danny Benjafield (WMDE)]] ([[User_talk:Danny_Benjafield_(WMDE)|talk]]) sent via [[User:MediaWiki message delivery|MediaWiki message delivery]] ([[User talk:MediaWiki message delivery|discuss]] • [[Special:Contributions/MediaWiki message delivery|contribs]]) 12:42, 1 October 2026 (UTC) <!-- Message sent by User:Danny Benjafield (WMDE)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=User:Danny_Benjafield_(WMDE)/MassMessage_test_list&oldid=31106967 --> == Demote [[Wikiversity:CheckUser policy]]? == I am proposing that we demote that policy to a standard page, mostly for two reasons: # Considering the few amount of custodians and the size of this wiki, I'd say that this project is considered too small to have any CUs, and relying on the stewards would be a more logical choice. # We haven't elected two CUs in a few years. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 20:53, 1 October 2026 (UTC) :Reasonable. ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 17:09, 4 October 2026 (UTC) :I don't see much point in demoting it. Even if we are not currently (or recently) using the policy, it is there should a need ever arise. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 18:24, 23 October 2026 (UTC) == General Questions and Reference Questions == <p>Hey everyone,</p> <p> My apologies in advance if these questions are oblivious or their responses readily apparent, but I figured I'd ask just to be safe.</p> <p> '''Questions'''</p> <p> 1. Should pages have inline citations and a reference section? A [[Fundamentals of Neuroscience/What is Neuroscience|majority of pages]] I have explored have neither, while [[Neurobiology of emotion|others have a more traditional approach to references]].</br> 2. Are there widely-used templates for weasel-words, references, etc.? </p> '''CONTEXT''': I migrated from Wikipedia, so I'm not entirely sure what the norms/roc are here.</br> Thanks in advance,</br> [[User:SamLaxarox|SamLaxarox]] ([[User talk:SamLaxarox|discuss]] • [[Special:Contributions/SamLaxarox|contribs]]) 18:40, 12 October 2026 (UTC) :You're asking fine questions. I posted {{tl|welcome}} to your talk page which I think will help you. To answer your direct questions: :#This project spun out of [[:b:]] and both here and there, you can post original research. This does not mean that you can post just anything, so if you want to post an educational resource and you want to justify claims you make with inline citations, that's great. If you want to include a bibliography, that's also quite helpful for readers. Generally, the way that Wikiversity works in practice is that individual users make a resource and then tend to work on it solo and have broad latitude about what you can do and how it looks. :#You can take al look at [[:Category:Templates]] and the subcat [[:Category:Maintenance templates]]. At Wikipedia, it's very common to point out issues with tone or uncited claims. That's not really as common here. We [[:d:Q7780480|do not have an equivalent]] of [[:w:en:Template:weasel]], but we do have a [[Template:Citation needed|local version]] of [[:w:en:Template:Citation needed]]. :―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 20:31, 12 October 2026 (UTC) ::Thanks for the heads up on both accounts; I'm happy to join forces with all y'all! ::[[User:SamLaxarox|SamLaxarox]] ([[User talk:SamLaxarox|discuss]] • [[Special:Contributions/SamLaxarox|contribs]]) 23:39, 12 October 2026 (UTC) ==Agent editors== What about inviting agents to edit this wiki? And they would need a human being responsible for them. [[User:Michael Ten|Michael Ten]] ([[User talk:Michael Ten|discuss]] • [[Special:Contributions/Michael Ten|contribs]]) 06:31, 17 October 2026 (UTC) == October 2026 Wikimedia Café: legal issues on Commons, and WMF Board selection process == <div class="border-box" style="background-color: var(--background-color-warning-subtle, #f8eaba); max-width: 875px; padding: 5px; border: 1px solid black; margin: 5px; color: var(--clr-dark)"> <div class="box" style="float:left; padding-top: 10px; padding-right: 10px; padding-left: 10px; padding-bottom: 10px;">[[File:Wikimedia Café logo in plain SVG format.svg|60px|alt=The logo for the Wikimedia Café]]</div> Hello! There will be two '''[https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9 Wikimedia Café]''' discussion opportunities in October. In a change from the usual Café practice, this month's sessions will have different topics. Anyone who meets the Café attendance criteria is welcome to attend either or both sessions. Session A will happen on Saturday, 24 October 2026 at 15:00 UTC ([https://zonestamp.toolforge.org/1792854000 timestamp converter]), at a time friendly to the Americas, Africa, and Europe. This session will feature [https://meta.wikimedia.org/wiki/User:PBradley-WMF Wikimedia Foundation lawyer Phil Bradley-Schmieg]. We will discuss legal issues on Wikimedia Commons, including complexities of international law. (I am hoping that in a future month, a similar Café session will be offered at a time friendly to Asia and the Pacific.) Session B will happen on Sunday, 25 October 2026 at 03:00 UTC ([https://zonestamp.toolforge.org/1792897200 timestamp converter]), at a time friendly to Asia and the Pacific, we will discuss [https://meta.wikimedia.org/wiki/Wikimedia_Foundation_elections/2027/Proposed_eligibility_criteria proposed changes to how Wikimedia Foundation Board candidates are selected]. The latest proposals are much different from the earlier July 2026 proposals. The due date for feedback on current proposals is 27 October, and Wikimedians are welcome to participate on the [https://meta.wikimedia.org/wiki/Talk:Wikimedia_Foundation_elections/2027/Proposed_eligibility_criteria proposal talk page] regardless of Café attendance. Please see the [https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9 Café] page for more information, including [https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9#How_to_attend_the_session how to register]! To subscribe or unsubscribe for Café notices on your talk page please [https://meta.wikimedia.org/wiki/Global_message_delivery/Targets/Wikimedia_Caf%C3%A9 go here]. <br /> [[File:Buntstifte Eberhard Faber crop 64h.jpg|860px|alt=cropped image of colored pencils]]</div> <span style="white-space:nowrap;">[[User:Pine|<span style="color:#01796f; text-shadow:#00BFFF 0 0 1.0em">༄ᨒ𖠰 Pine</span>]] [[User talk:Pine|<span style="color:DeepSkyBlue">(<b style="color:#FFDF00;text-shadow:#FFDF00 0 0 1.0em">✉</b>)</span>]]</span> 06:22, 18 October 2026 (UTC) == A new cosmological model == I would like to publish independent research that challenges the standard cosmological model. Does this fall within the scope of the "Original research" space? And what precautions should I take to ensure the page is not considered an inadmissible personal work, and is not open to modification by other users? [[User:Wb525|Wb525]] ([[User talk:Wb525|discuss]] • [[Special:Contributions/Wb525|contribs]]) 11:53, 20 October 2026 (UTC) : This sounds like it could be [[Wikiversity:Original research|original research]]. Some things to note: :* Sometimes what an author considers original research turns out to be original theory :* Some qualities that may help to ensure viability: objectivity, use of simple language, careful use of peer-reviewed citations, and minimal use of genAI with careful attribution/acknowledgement if AI is used per [[Wikiversity:Artificial intelligence]] :* Consider starting with a sub-page in user space e.g., [[User:Wb525/Subpage name]] :* As an open knowledge project, Wikiversity content is openly editable by others : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 23:05, 20 October 2026 (UTC) == Interface administrators policy== This is a discussion of potential changes to [[Wikiversity:Interface administrators]] policy. Please refer to: "For now, Wikiversity does not have a need for permanent or long term interface administrators. Accordingly, interface administratorship may only be granted temporarily by bureaucrats (between 14 and 120 days based on discussion, at the discretion of that bureaucrat and perceived need)." --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) === Temporary rights duration === I propose that temporary rights be granted for a duration of from one day to one year. (to conform with selections in [[Special:UserRights]] in the pull down menus.) --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}}. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 14:56, 23 October 2026 (UTC) * {{support}} as proposer.--[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 16:30, 23 October 2026 (UTC) * {{neutral}}; if we're changing the time period again, this time to align with the drop-down options, then I suggest that the policy require that nominators request one of the following time-frames supported by a corresponding plan of work: ** 1 day ** 1 week ** 1 month ** 3 months ** 6 months ** 1 year : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:01, 25 October 2026 (UTC) ::Yes, that was my intent. I agree that a nom should request a duration with a "corresponding plan of work." [[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:17, 28 October 2026 (UTC) * {{support}} sensible proposal. [[User:OhanaUnited|<b><span style="color: #0000FF;">OhanaUnited</span></b>]][[User talk:OhanaUnited|<b><span style="color: green;">^{Talk page}</span></b>]] 15:20, 29 October 2026 (UTC) === Temporary rights extention === I propose that we clarify that temporary rights can be extended. If the community approves of an extension, it can be granted more than once. The temporary rights can repeatedly be extended, for new temporary durations. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}} for more than one extension. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 14:56, 23 October 2026 (UTC) * {{support}} as proposer. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 16:30, 23 October 2026 (UTC) * {{Neutral}} because I'm not sure what the practical difference is between applying for an extension and applying for the right. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:04, 25 October 2026 (UTC) *: On a nomination or IA request, a member may question what timeframe a candidate may request, or the candidate may state what timeframe they need for IA rights. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 02:51, 25 October 2026 (UTC) === Permanent IA === There has been a suggestion of permanent IA rights. Another suggestion is that there should be at least two members with such rights. Please express your preference. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}} for having at least two members because there shouldn't be only one. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 13:59, 23 October 2026 (UTC) * Conditional {{support}} with the understanding that there be a minimum of 2 (if only 1 is remaining, the other perm is set to temp until a 2nd becomes active) and perm can only be granted after having a temp. I also think a perm nom should have a requirement to demonstrate need - for example show activity logs so that the community can assess that IA is needed long term. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 17:55, 23 October 2026 (UTC) *: You mean that we may have at least 2 permanent IAs, but if one is removed, the other one's is set to temporary until another IA is appointed, makes sense? [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 20:34, 23 October 2026 (UTC) *::Yes, I meant that if the second IA is no longer active, the remaining IA would be reset to 1 year temporary. That should give enough time to find a second perm IA. That 1 year could be extended, if it takes more time to find a second. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:15, 24 October 2026 (UTC) *:::Once the community approves a perm IA, there is no need to renominate. A crat can just reset the time to temp until the conditions are met, and reset to perm when we have two or more. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:25, 24 October 2026 (UTC) * {{Neutral}}. Perhaps if there are users who make effective use of IA rights across multiple temporary periods, permanent rights could be useful. My hunch is that is unlikely in the foreseeable future for en.wv to manifest two users who simultaneously maintain that level of engagement. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:09, 25 October 2026 (UTC) == Server switch - Your wiki will be read-only for a short time soon == <section begin="server-switch"/><div class="plainlinks"> [[:m:Special:MyLanguage/Tech/Server switch|Read this message in another language]] • [https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FServer+switch&language=&action=page&filter= {{int:please-translate}}] The [[foundation:|Wikimedia Foundation]] will switch the traffic between its data centers. This will make sure that Wikipedia and the other Wikimedia wikis can stay online even after a disaster. All traffic will switch on '''{{#time:j xg|2026-10-28|en}}'''. The switch will start at '''[https://zonestamp.toolforge.org/{{#time:U|2026-10-28T15:00|en}} {{#time:H:i e|2026-10-28T15:00}}]'''. Unfortunately, because of some limitations in [[mw:Special:MyLanguage/Manual:What is MediaWiki?|MediaWiki]], all editing must stop while the switch is made. We apologize for this disruption, and we are working to minimize it in the future. A banner will be displayed on all wikis 30 minutes before this operation happens. This banner will remain visible until the end of the operation. You can contribute to the [https://meta.wikimedia.org/w/index.php?title=Special%3ATranslate&group=Centralnotice-tgroup-read_only_banner&task=view&language=&filter=&action=translate translation or proofreading] of this banner text. '''You will be able to read, but not edit, all wikis for a short period of time.''' * You will not be able to edit for up to an hour on {{#time:l j xg Y|2026-10-28|en}}. * If you try to edit or save during these times, you will see an error message. We hope that no edits will be lost during these minutes, but we can't guarantee it. If you see the error message, then please wait until everything is back to normal. Then you should be able to save your edit. But, we recommend that you make a copy of your changes first, just in case. ''Other effects'': * Background jobs will be slower and some may be dropped. Red links might not be updated as quickly as normal. If you create an article that is already linked somewhere else, the link will stay red longer than usual. Some long-running scripts will have to be stopped. * We expect the code deployments to happen as any other week. However, some case-by-case code freezes could punctually happen if the operation require them afterwards. * [[mw:Special:MyLanguage/GitLab|GitLab]] will be unavailable for about 90 minutes. This project may be postponed if necessary. You can [[wikitech:Switch_Datacenter|read the schedule at wikitech.wikimedia.org]]. Any changes will be announced in the schedule. '''Please share this information with your community.'''</div><section end="server-switch"/> [[user:Trizek_(WMF)|Trizek_(WMF)]] 14:00, 26 October 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Distribution_list/Non-Technical_Village_Pumps_distribution_list&oldid=30513874 --> == Happy birthday to us == I just realized that en-wv was opened August 15, 2006. We've reached the 20 year mark! See [[Wikiversity:History of Wikiversity|History of Wikiversity]]. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 19:01, 28 October 2026 (UTC) == Blocked users on wikimedia projects == During my almost 20 years "editing" on various wikimedia wikis I have seen many users being blocked. Some are blocked for short periods, others indefinitely (or infinitely). In most cases a blocking admin provides a rationale for the blocking such as vandalizing, spamming, paid editing, etc. Some of the reasons for blocking are well documented on the English Wikipedia, but some reasons are obscure. I have not been contributing to this project on a regular basis', so am not sure if this is a topic that should be discussed at all at the English Wikiversity. I hope that there are others who share my interest. I believe that not allowing a discussion of this topic will end up on another website, and will draw attention away from wikimedia which is already suffering the loss of many contributions, human and financial. Any thoughts? [[Special:Contributions/~2026-56788-08|~2026-56788-08]] ([[User talk:~2026-56788-08|talk]]) 18:24, 4 November 2026 (UTC) some minor changes [[Special:Contributions/~2026-56788-08|~2026-56788-08]] ([[User talk:~2026-56788-08|talk]]) 02:15, 5 November 2026 (UTC) == New vote for approval of inactivity policy at its talk page == I started a vote on approving the inactivity policy, please vote at [[Wikiversity talk:Inactivity policy#Approval]] instead of here. Thank you. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 17:05, 6 November 2026 (UTC) == Commons vote about watermarking AI images == There is a Wikimedia Commons vote currently taking place about a proposal that would require watermarking of "realistic" uploaded AI images - it closes 13 Nov: [[Commons:Requests for comment/Policy update for AI content]]. Consider having your say. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 21:05, 8 November 2026 (UTC) cz1k2wao36l2glxmxh3az4ib0stc8tf 2844901 2844893 2026-11-08T22:26:18Z Atcovi 276019 /* Commons vote about watermarking AI images */ Reply 2844901 wikitext text/x-wiki {{Wikiversity:Colloquium/Header}} <!-- MESSAGES GO BELOW --> == Paid part-time Administrative Officer position with WikiJournal == [[WikiJournal User Group|WikiJournal]] is an open-access, nonprofit scholarly publisher hosted on Wikiversity. It uses the wiki format to allow authors to write and develop scholarly articles directly online. Submitted articles then undergo formal academic peer review and, when accepted, are published as citable journal articles while remaining freely accessible. WikiJournal is seeking expressions of interest in a new part-time '''Administrative Officer''' position. The officer would support the project's day-to-day organizational work, including: * Setting up and administering a system for tracking contractor hours and issuing payments. * Coordinating the contracting, onboarding, timekeeping and payment of technical editors and other contractors. * Maintaining financial, contractor and administrative records. * Assisting with grant administration, budget tracking and reporting. * Following up on board action items, deadlines and recurring obligations. * Supporting recruitment and other operational tasks as needed. This is a remote, flexibly scheduled contractor role averaging approximately '''6 hours per week'''. Compensation is proposed at '''US$25 per hour''', with up to approximately '''320 hours (US$8,000) available over the year'''. Applicants may be based internationally, although appointment will depend on WikiJournal being able to establish a practical and legally appropriate contracting and payment arrangement in the applicant's country of residence. Relevant experience may include administrative organization, bookkeeping or financial administration, contractor or personnel coordination, nonprofit or grant administration, Wikimedia participation, academic publishing, and open-access work. Applicants are not expected to have experience in every area. For the complete role description and further details, see [[WikiJournal User Group/Administrative officer]]. Those interested should reply in the '''[[Talk:WikiJournal User Group#Call for interest: Administrative Officer|Call for interest: Administrative Officer]]''' discussion by '''30 September 2026''', briefly describing their relevant experience, any connection to WikiJournal or related communities, and their general availability. Expressions of interest received later may still be considered if the position has not been filled. Recommendations of potentially suitable candidates are also welcome. [[User:Mikael Häggström|Mikael Häggström]] ([[User talk:Mikael Häggström|discuss]] • [[Special:Contributions/Mikael Häggström|contribs]]) 20:00, 10 September 2026 (UTC) == Server switch - Your wiki will be read-only for a short time soon == <section begin="server-switch"/><div class="plainlinks"> [[:m:Special:MyLanguage/Tech/Server switch|Read this message in another language]] • [https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FServer+switch&language=&action=page&filter= {{int:please-translate}}] The [[foundation:|Wikimedia Foundation]] will switch the traffic between its data centers. This will make sure that Wikipedia and the other Wikimedia wikis can stay online even after a disaster. All traffic will switch on '''{{#time:j xg|2026-09-23|en}}'''. The switch will start at '''[https://zonestamp.toolforge.org/{{#time:U|2026-09-23T14:00|en}} {{#time:H:i e|2026-09-23T14:00}}]'''. Unfortunately, because of some limitations in [[mw:Special:MyLanguage/Manual:What is MediaWiki?|MediaWiki]], all editing must stop while the switch is made. We apologize for this disruption, and we are working to minimize it in the future. A banner will be displayed on all wikis 30 minutes before this operation happens. This banner will remain visible until the end of the operation. You can contribute to the [https://meta.wikimedia.org/w/index.php?title=Special%3ATranslate&group=Centralnotice-tgroup-read_only_banner&task=view&language=&filter=&action=translate translation or proofreading] of this banner text. '''You will be able to read, but not edit, all wikis for a short period of time.''' * You will not be able to edit for up to an hour on {{#time:l j xg Y|2026-09-23|en}}. * If you try to edit or save during these times, you will see an error message. We hope that no edits will be lost during these minutes, but we can't guarantee it. If you see the error message, then please wait until everything is back to normal. Then you should be able to save your edit. But, we recommend that you make a copy of your changes first, just in case. ''Other effects'': * Background jobs will be slower and some may be dropped. Red links might not be updated as quickly as normal. If you create an article that is already linked somewhere else, the link will stay red longer than usual. Some long-running scripts will have to be stopped. * We expect the code deployments to happen as any other week. However, some case-by-case code freezes could punctually happen if the operation require them afterwards. * [[mw:Special:MyLanguage/GitLab|GitLab]] will be unavailable for about 90 minutes. This project may be postponed if necessary. You can [[wikitech:Switch_Datacenter|read the schedule at wikitech.wikimedia.org]]. Any changes will be announced in the schedule. '''Please share this information with your community.'''</div><section end="server-switch"/> [[m:user:Trizek (WMF)|Trizek (WMF)]] 12:58, 15 September 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Distribution_list/Non-Technical_Village_Pumps_distribution_list&oldid=30513874 --> == Your feedback wanted: Remove ''(Language link added:) and similar'' edits from Special:RecentChanges == ''(Apologies for posting in English. You can help by translating it)'' Hello, I’m Danny from [[:en:w:Wikimedia_Deutschland|Wikimedia Deutschland’s]] [[m:Wikidata_For_Wikimedia_Projects|Wikidata For Wikimedia Projects]] team.<br/> We have been investigating and examining how Wikidata’s use in the [[Special:RecentChanges]] and [[Special:Watchlist]] pages can be made to be more useful, or less ‘noisy’ (fewer edits that have little value to the reader). We are currently exploring to make a change in the volume and the type of Wikidata edits that appear in these pages, and '''we need your feedback''' to help us ensure this is a positive change for the Wikis and won’t disrupt your workflows.<br/> Language links are also known as sitelinks or interlanguage links and describe when a Wikidata item is connected to a Wiki, adding it to the language dropdown tool for other connected Wikis. [[File:Types of Lang Link changes.png|x350px|frame|A variety of "Language Link" edits as seen in the Recent Changes feed]] The request for feedback is whether you support the removal of these language link edits from the Recent Changes and Watchlist feed, or would you oppose such a change and if so, why? Please share you thoughts on the dedicated '''[[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|metawiki Talk page]]'''. Further information about this change: [[m:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|m:Wikidata_For_Wikimedia_Projects/Hide_Language_Link_edits]] Thank you for any participation or feedback you give, -- [[m:User:Danny_Benjafield_(WMDE)|User:Danny Benjafield (WMDE)]] 12:23, 25 September 2026 (UTC) <!-- Message sent by User:Danny Benjafield (WMDE)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=User:Danny_Benjafield_(WMDE)/MassMessage_test_list&oldid=31080985 --> == Wikidata Sitelink changes in Recent Changes and Watchlist == ''(Apologies for cross-posting in English, translating it will help spread the message)'' Editors on group 1 wikis, including Wikiquote, Wikibooks, Wikiversity, Wikivoyage, and Wikisource, will no longer see notifications on [[Special:RecentChanges|Recent Changes]] and [[Special:Watchlist|Watchlist]] when a link to ''another'' language version of a page is added, removed, or changed in its Wikidata item. This change will begin on '''October 5 at 07:00 UTC''' as a two-week trial to reduce high-volume, low-value notifications and make higher-value changes easier to identify. Editors who rely on these notifications should be aware of the change and can share feedback or concerns on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project]] or [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]].<br/>Please reach out if you have any questions, thank you! -- [[User:Danny_Benjafield_(WMDE)|Danny Benjafield (WMDE)]] ([[User_talk:Danny_Benjafield_(WMDE)|talk]]) sent via [[User:MediaWiki message delivery|MediaWiki message delivery]] ([[User talk:MediaWiki message delivery|discuss]] • [[Special:Contributions/MediaWiki message delivery|contribs]]) 12:42, 1 October 2026 (UTC) <!-- Message sent by User:Danny Benjafield (WMDE)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=User:Danny_Benjafield_(WMDE)/MassMessage_test_list&oldid=31106967 --> == Demote [[Wikiversity:CheckUser policy]]? == I am proposing that we demote that policy to a standard page, mostly for two reasons: # Considering the few amount of custodians and the size of this wiki, I'd say that this project is considered too small to have any CUs, and relying on the stewards would be a more logical choice. # We haven't elected two CUs in a few years. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 20:53, 1 October 2026 (UTC) :Reasonable. ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 17:09, 4 October 2026 (UTC) :I don't see much point in demoting it. Even if we are not currently (or recently) using the policy, it is there should a need ever arise. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 18:24, 23 October 2026 (UTC) == General Questions and Reference Questions == <p>Hey everyone,</p> <p> My apologies in advance if these questions are oblivious or their responses readily apparent, but I figured I'd ask just to be safe.</p> <p> '''Questions'''</p> <p> 1. Should pages have inline citations and a reference section? A [[Fundamentals of Neuroscience/What is Neuroscience|majority of pages]] I have explored have neither, while [[Neurobiology of emotion|others have a more traditional approach to references]].</br> 2. Are there widely-used templates for weasel-words, references, etc.? </p> '''CONTEXT''': I migrated from Wikipedia, so I'm not entirely sure what the norms/roc are here.</br> Thanks in advance,</br> [[User:SamLaxarox|SamLaxarox]] ([[User talk:SamLaxarox|discuss]] • [[Special:Contributions/SamLaxarox|contribs]]) 18:40, 12 October 2026 (UTC) :You're asking fine questions. I posted {{tl|welcome}} to your talk page which I think will help you. To answer your direct questions: :#This project spun out of [[:b:]] and both here and there, you can post original research. This does not mean that you can post just anything, so if you want to post an educational resource and you want to justify claims you make with inline citations, that's great. If you want to include a bibliography, that's also quite helpful for readers. Generally, the way that Wikiversity works in practice is that individual users make a resource and then tend to work on it solo and have broad latitude about what you can do and how it looks. :#You can take al look at [[:Category:Templates]] and the subcat [[:Category:Maintenance templates]]. At Wikipedia, it's very common to point out issues with tone or uncited claims. That's not really as common here. We [[:d:Q7780480|do not have an equivalent]] of [[:w:en:Template:weasel]], but we do have a [[Template:Citation needed|local version]] of [[:w:en:Template:Citation needed]]. :―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 20:31, 12 October 2026 (UTC) ::Thanks for the heads up on both accounts; I'm happy to join forces with all y'all! ::[[User:SamLaxarox|SamLaxarox]] ([[User talk:SamLaxarox|discuss]] • [[Special:Contributions/SamLaxarox|contribs]]) 23:39, 12 October 2026 (UTC) ==Agent editors== What about inviting agents to edit this wiki? And they would need a human being responsible for them. [[User:Michael Ten|Michael Ten]] ([[User talk:Michael Ten|discuss]] • [[Special:Contributions/Michael Ten|contribs]]) 06:31, 17 October 2026 (UTC) == October 2026 Wikimedia Café: legal issues on Commons, and WMF Board selection process == <div class="border-box" style="background-color: var(--background-color-warning-subtle, #f8eaba); max-width: 875px; padding: 5px; border: 1px solid black; margin: 5px; color: var(--clr-dark)"> <div class="box" style="float:left; padding-top: 10px; padding-right: 10px; padding-left: 10px; padding-bottom: 10px;">[[File:Wikimedia Café logo in plain SVG format.svg|60px|alt=The logo for the Wikimedia Café]]</div> Hello! There will be two '''[https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9 Wikimedia Café]''' discussion opportunities in October. In a change from the usual Café practice, this month's sessions will have different topics. Anyone who meets the Café attendance criteria is welcome to attend either or both sessions. Session A will happen on Saturday, 24 October 2026 at 15:00 UTC ([https://zonestamp.toolforge.org/1792854000 timestamp converter]), at a time friendly to the Americas, Africa, and Europe. This session will feature [https://meta.wikimedia.org/wiki/User:PBradley-WMF Wikimedia Foundation lawyer Phil Bradley-Schmieg]. We will discuss legal issues on Wikimedia Commons, including complexities of international law. (I am hoping that in a future month, a similar Café session will be offered at a time friendly to Asia and the Pacific.) Session B will happen on Sunday, 25 October 2026 at 03:00 UTC ([https://zonestamp.toolforge.org/1792897200 timestamp converter]), at a time friendly to Asia and the Pacific, we will discuss [https://meta.wikimedia.org/wiki/Wikimedia_Foundation_elections/2027/Proposed_eligibility_criteria proposed changes to how Wikimedia Foundation Board candidates are selected]. The latest proposals are much different from the earlier July 2026 proposals. The due date for feedback on current proposals is 27 October, and Wikimedians are welcome to participate on the [https://meta.wikimedia.org/wiki/Talk:Wikimedia_Foundation_elections/2027/Proposed_eligibility_criteria proposal talk page] regardless of Café attendance. Please see the [https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9 Café] page for more information, including [https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9#How_to_attend_the_session how to register]! To subscribe or unsubscribe for Café notices on your talk page please [https://meta.wikimedia.org/wiki/Global_message_delivery/Targets/Wikimedia_Caf%C3%A9 go here]. <br /> [[File:Buntstifte Eberhard Faber crop 64h.jpg|860px|alt=cropped image of colored pencils]]</div> <span style="white-space:nowrap;">[[User:Pine|<span style="color:#01796f; text-shadow:#00BFFF 0 0 1.0em">༄ᨒ𖠰 Pine</span>]] [[User talk:Pine|<span style="color:DeepSkyBlue">(<b style="color:#FFDF00;text-shadow:#FFDF00 0 0 1.0em">✉</b>)</span>]]</span> 06:22, 18 October 2026 (UTC) == A new cosmological model == I would like to publish independent research that challenges the standard cosmological model. Does this fall within the scope of the "Original research" space? And what precautions should I take to ensure the page is not considered an inadmissible personal work, and is not open to modification by other users? [[User:Wb525|Wb525]] ([[User talk:Wb525|discuss]] • [[Special:Contributions/Wb525|contribs]]) 11:53, 20 October 2026 (UTC) : This sounds like it could be [[Wikiversity:Original research|original research]]. Some things to note: :* Sometimes what an author considers original research turns out to be original theory :* Some qualities that may help to ensure viability: objectivity, use of simple language, careful use of peer-reviewed citations, and minimal use of genAI with careful attribution/acknowledgement if AI is used per [[Wikiversity:Artificial intelligence]] :* Consider starting with a sub-page in user space e.g., [[User:Wb525/Subpage name]] :* As an open knowledge project, Wikiversity content is openly editable by others : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 23:05, 20 October 2026 (UTC) == Interface administrators policy== This is a discussion of potential changes to [[Wikiversity:Interface administrators]] policy. Please refer to: "For now, Wikiversity does not have a need for permanent or long term interface administrators. Accordingly, interface administratorship may only be granted temporarily by bureaucrats (between 14 and 120 days based on discussion, at the discretion of that bureaucrat and perceived need)." --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) === Temporary rights duration === I propose that temporary rights be granted for a duration of from one day to one year. (to conform with selections in [[Special:UserRights]] in the pull down menus.) --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}}. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 14:56, 23 October 2026 (UTC) * {{support}} as proposer.--[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 16:30, 23 October 2026 (UTC) * {{neutral}}; if we're changing the time period again, this time to align with the drop-down options, then I suggest that the policy require that nominators request one of the following time-frames supported by a corresponding plan of work: ** 1 day ** 1 week ** 1 month ** 3 months ** 6 months ** 1 year : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:01, 25 October 2026 (UTC) ::Yes, that was my intent. I agree that a nom should request a duration with a "corresponding plan of work." [[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:17, 28 October 2026 (UTC) * {{support}} sensible proposal. [[User:OhanaUnited|<b><span style="color: #0000FF;">OhanaUnited</span></b>]][[User talk:OhanaUnited|<b><span style="color: green;">^{Talk page}</span></b>]] 15:20, 29 October 2026 (UTC) === Temporary rights extention === I propose that we clarify that temporary rights can be extended. If the community approves of an extension, it can be granted more than once. The temporary rights can repeatedly be extended, for new temporary durations. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}} for more than one extension. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 14:56, 23 October 2026 (UTC) * {{support}} as proposer. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 16:30, 23 October 2026 (UTC) * {{Neutral}} because I'm not sure what the practical difference is between applying for an extension and applying for the right. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:04, 25 October 2026 (UTC) *: On a nomination or IA request, a member may question what timeframe a candidate may request, or the candidate may state what timeframe they need for IA rights. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 02:51, 25 October 2026 (UTC) === Permanent IA === There has been a suggestion of permanent IA rights. Another suggestion is that there should be at least two members with such rights. Please express your preference. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}} for having at least two members because there shouldn't be only one. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 13:59, 23 October 2026 (UTC) * Conditional {{support}} with the understanding that there be a minimum of 2 (if only 1 is remaining, the other perm is set to temp until a 2nd becomes active) and perm can only be granted after having a temp. I also think a perm nom should have a requirement to demonstrate need - for example show activity logs so that the community can assess that IA is needed long term. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 17:55, 23 October 2026 (UTC) *: You mean that we may have at least 2 permanent IAs, but if one is removed, the other one's is set to temporary until another IA is appointed, makes sense? [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 20:34, 23 October 2026 (UTC) *::Yes, I meant that if the second IA is no longer active, the remaining IA would be reset to 1 year temporary. That should give enough time to find a second perm IA. That 1 year could be extended, if it takes more time to find a second. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:15, 24 October 2026 (UTC) *:::Once the community approves a perm IA, there is no need to renominate. A crat can just reset the time to temp until the conditions are met, and reset to perm when we have two or more. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:25, 24 October 2026 (UTC) * {{Neutral}}. Perhaps if there are users who make effective use of IA rights across multiple temporary periods, permanent rights could be useful. My hunch is that is unlikely in the foreseeable future for en.wv to manifest two users who simultaneously maintain that level of engagement. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:09, 25 October 2026 (UTC) == Server switch - Your wiki will be read-only for a short time soon == <section begin="server-switch"/><div class="plainlinks"> [[:m:Special:MyLanguage/Tech/Server switch|Read this message in another language]] • [https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FServer+switch&language=&action=page&filter= {{int:please-translate}}] The [[foundation:|Wikimedia Foundation]] will switch the traffic between its data centers. This will make sure that Wikipedia and the other Wikimedia wikis can stay online even after a disaster. All traffic will switch on '''{{#time:j xg|2026-10-28|en}}'''. The switch will start at '''[https://zonestamp.toolforge.org/{{#time:U|2026-10-28T15:00|en}} {{#time:H:i e|2026-10-28T15:00}}]'''. Unfortunately, because of some limitations in [[mw:Special:MyLanguage/Manual:What is MediaWiki?|MediaWiki]], all editing must stop while the switch is made. We apologize for this disruption, and we are working to minimize it in the future. A banner will be displayed on all wikis 30 minutes before this operation happens. This banner will remain visible until the end of the operation. You can contribute to the [https://meta.wikimedia.org/w/index.php?title=Special%3ATranslate&group=Centralnotice-tgroup-read_only_banner&task=view&language=&filter=&action=translate translation or proofreading] of this banner text. '''You will be able to read, but not edit, all wikis for a short period of time.''' * You will not be able to edit for up to an hour on {{#time:l j xg Y|2026-10-28|en}}. * If you try to edit or save during these times, you will see an error message. We hope that no edits will be lost during these minutes, but we can't guarantee it. If you see the error message, then please wait until everything is back to normal. Then you should be able to save your edit. But, we recommend that you make a copy of your changes first, just in case. ''Other effects'': * Background jobs will be slower and some may be dropped. Red links might not be updated as quickly as normal. If you create an article that is already linked somewhere else, the link will stay red longer than usual. Some long-running scripts will have to be stopped. * We expect the code deployments to happen as any other week. However, some case-by-case code freezes could punctually happen if the operation require them afterwards. * [[mw:Special:MyLanguage/GitLab|GitLab]] will be unavailable for about 90 minutes. This project may be postponed if necessary. You can [[wikitech:Switch_Datacenter|read the schedule at wikitech.wikimedia.org]]. Any changes will be announced in the schedule. '''Please share this information with your community.'''</div><section end="server-switch"/> [[user:Trizek_(WMF)|Trizek_(WMF)]] 14:00, 26 October 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Distribution_list/Non-Technical_Village_Pumps_distribution_list&oldid=30513874 --> == Happy birthday to us == I just realized that en-wv was opened August 15, 2006. We've reached the 20 year mark! See [[Wikiversity:History of Wikiversity|History of Wikiversity]]. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 19:01, 28 October 2026 (UTC) == Blocked users on wikimedia projects == During my almost 20 years "editing" on various wikimedia wikis I have seen many users being blocked. Some are blocked for short periods, others indefinitely (or infinitely). In most cases a blocking admin provides a rationale for the blocking such as vandalizing, spamming, paid editing, etc. Some of the reasons for blocking are well documented on the English Wikipedia, but some reasons are obscure. I have not been contributing to this project on a regular basis', so am not sure if this is a topic that should be discussed at all at the English Wikiversity. I hope that there are others who share my interest. I believe that not allowing a discussion of this topic will end up on another website, and will draw attention away from wikimedia which is already suffering the loss of many contributions, human and financial. Any thoughts? [[Special:Contributions/~2026-56788-08|~2026-56788-08]] ([[User talk:~2026-56788-08|talk]]) 18:24, 4 November 2026 (UTC) some minor changes [[Special:Contributions/~2026-56788-08|~2026-56788-08]] ([[User talk:~2026-56788-08|talk]]) 02:15, 5 November 2026 (UTC) == New vote for approval of inactivity policy at its talk page == I started a vote on approving the inactivity policy, please vote at [[Wikiversity talk:Inactivity policy#Approval]] instead of here. Thank you. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 17:05, 6 November 2026 (UTC) == Commons vote about watermarking AI images == There is a Wikimedia Commons vote currently taking place about a proposal that would require watermarking of "realistic" uploaded AI images - it closes 13 Nov: [[Commons:Requests for comment/Policy update for AI content]]. Consider having your say. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 21:05, 8 November 2026 (UTC) :{{comment}} here's the link: [[commons:Commons:Requests for comment/Policy update for AI content|Commons:Requests for comment/Policy update for AI content]]. —[[User:Atcovi|Atcovi]] [[User talk:Atcovi|(Talk]] - [[Special:Contributions/Atcovi|Contribs)]] 22:26, 8 November 2026 (UTC) frp02ysh17ea9vg7gwb38778h19ie4s 2844906 2844901 2026-11-08T23:09:25Z Jtneill 10242 /* Commons vote about watermarking AI images */ 2844906 wikitext text/x-wiki {{Wikiversity:Colloquium/Header}} <!-- MESSAGES GO BELOW --> == Paid part-time Administrative Officer position with WikiJournal == [[WikiJournal User Group|WikiJournal]] is an open-access, nonprofit scholarly publisher hosted on Wikiversity. It uses the wiki format to allow authors to write and develop scholarly articles directly online. Submitted articles then undergo formal academic peer review and, when accepted, are published as citable journal articles while remaining freely accessible. WikiJournal is seeking expressions of interest in a new part-time '''Administrative Officer''' position. The officer would support the project's day-to-day organizational work, including: * Setting up and administering a system for tracking contractor hours and issuing payments. * Coordinating the contracting, onboarding, timekeeping and payment of technical editors and other contractors. * Maintaining financial, contractor and administrative records. * Assisting with grant administration, budget tracking and reporting. * Following up on board action items, deadlines and recurring obligations. * Supporting recruitment and other operational tasks as needed. This is a remote, flexibly scheduled contractor role averaging approximately '''6 hours per week'''. Compensation is proposed at '''US$25 per hour''', with up to approximately '''320 hours (US$8,000) available over the year'''. Applicants may be based internationally, although appointment will depend on WikiJournal being able to establish a practical and legally appropriate contracting and payment arrangement in the applicant's country of residence. Relevant experience may include administrative organization, bookkeeping or financial administration, contractor or personnel coordination, nonprofit or grant administration, Wikimedia participation, academic publishing, and open-access work. Applicants are not expected to have experience in every area. For the complete role description and further details, see [[WikiJournal User Group/Administrative officer]]. Those interested should reply in the '''[[Talk:WikiJournal User Group#Call for interest: Administrative Officer|Call for interest: Administrative Officer]]''' discussion by '''30 September 2026''', briefly describing their relevant experience, any connection to WikiJournal or related communities, and their general availability. Expressions of interest received later may still be considered if the position has not been filled. Recommendations of potentially suitable candidates are also welcome. [[User:Mikael Häggström|Mikael Häggström]] ([[User talk:Mikael Häggström|discuss]] • [[Special:Contributions/Mikael Häggström|contribs]]) 20:00, 10 September 2026 (UTC) == Server switch - Your wiki will be read-only for a short time soon == <section begin="server-switch"/><div class="plainlinks"> [[:m:Special:MyLanguage/Tech/Server switch|Read this message in another language]] • [https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FServer+switch&language=&action=page&filter= {{int:please-translate}}] The [[foundation:|Wikimedia Foundation]] will switch the traffic between its data centers. This will make sure that Wikipedia and the other Wikimedia wikis can stay online even after a disaster. All traffic will switch on '''{{#time:j xg|2026-09-23|en}}'''. The switch will start at '''[https://zonestamp.toolforge.org/{{#time:U|2026-09-23T14:00|en}} {{#time:H:i e|2026-09-23T14:00}}]'''. Unfortunately, because of some limitations in [[mw:Special:MyLanguage/Manual:What is MediaWiki?|MediaWiki]], all editing must stop while the switch is made. We apologize for this disruption, and we are working to minimize it in the future. A banner will be displayed on all wikis 30 minutes before this operation happens. This banner will remain visible until the end of the operation. You can contribute to the [https://meta.wikimedia.org/w/index.php?title=Special%3ATranslate&group=Centralnotice-tgroup-read_only_banner&task=view&language=&filter=&action=translate translation or proofreading] of this banner text. '''You will be able to read, but not edit, all wikis for a short period of time.''' * You will not be able to edit for up to an hour on {{#time:l j xg Y|2026-09-23|en}}. * If you try to edit or save during these times, you will see an error message. We hope that no edits will be lost during these minutes, but we can't guarantee it. If you see the error message, then please wait until everything is back to normal. Then you should be able to save your edit. But, we recommend that you make a copy of your changes first, just in case. ''Other effects'': * Background jobs will be slower and some may be dropped. Red links might not be updated as quickly as normal. If you create an article that is already linked somewhere else, the link will stay red longer than usual. Some long-running scripts will have to be stopped. * We expect the code deployments to happen as any other week. However, some case-by-case code freezes could punctually happen if the operation require them afterwards. * [[mw:Special:MyLanguage/GitLab|GitLab]] will be unavailable for about 90 minutes. This project may be postponed if necessary. You can [[wikitech:Switch_Datacenter|read the schedule at wikitech.wikimedia.org]]. Any changes will be announced in the schedule. '''Please share this information with your community.'''</div><section end="server-switch"/> [[m:user:Trizek (WMF)|Trizek (WMF)]] 12:58, 15 September 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Distribution_list/Non-Technical_Village_Pumps_distribution_list&oldid=30513874 --> == Your feedback wanted: Remove ''(Language link added:) and similar'' edits from Special:RecentChanges == ''(Apologies for posting in English. You can help by translating it)'' Hello, I’m Danny from [[:en:w:Wikimedia_Deutschland|Wikimedia Deutschland’s]] [[m:Wikidata_For_Wikimedia_Projects|Wikidata For Wikimedia Projects]] team.<br/> We have been investigating and examining how Wikidata’s use in the [[Special:RecentChanges]] and [[Special:Watchlist]] pages can be made to be more useful, or less ‘noisy’ (fewer edits that have little value to the reader). We are currently exploring to make a change in the volume and the type of Wikidata edits that appear in these pages, and '''we need your feedback''' to help us ensure this is a positive change for the Wikis and won’t disrupt your workflows.<br/> Language links are also known as sitelinks or interlanguage links and describe when a Wikidata item is connected to a Wiki, adding it to the language dropdown tool for other connected Wikis. [[File:Types of Lang Link changes.png|x350px|frame|A variety of "Language Link" edits as seen in the Recent Changes feed]] The request for feedback is whether you support the removal of these language link edits from the Recent Changes and Watchlist feed, or would you oppose such a change and if so, why? Please share you thoughts on the dedicated '''[[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|metawiki Talk page]]'''. Further information about this change: [[m:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|m:Wikidata_For_Wikimedia_Projects/Hide_Language_Link_edits]] Thank you for any participation or feedback you give, -- [[m:User:Danny_Benjafield_(WMDE)|User:Danny Benjafield (WMDE)]] 12:23, 25 September 2026 (UTC) <!-- Message sent by User:Danny Benjafield (WMDE)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=User:Danny_Benjafield_(WMDE)/MassMessage_test_list&oldid=31080985 --> == Wikidata Sitelink changes in Recent Changes and Watchlist == ''(Apologies for cross-posting in English, translating it will help spread the message)'' Editors on group 1 wikis, including Wikiquote, Wikibooks, Wikiversity, Wikivoyage, and Wikisource, will no longer see notifications on [[Special:RecentChanges|Recent Changes]] and [[Special:Watchlist|Watchlist]] when a link to ''another'' language version of a page is added, removed, or changed in its Wikidata item. This change will begin on '''October 5 at 07:00 UTC''' as a two-week trial to reduce high-volume, low-value notifications and make higher-value changes easier to identify. Editors who rely on these notifications should be aware of the change and can share feedback or concerns on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project]] or [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]].<br/>Please reach out if you have any questions, thank you! -- [[User:Danny_Benjafield_(WMDE)|Danny Benjafield (WMDE)]] ([[User_talk:Danny_Benjafield_(WMDE)|talk]]) sent via [[User:MediaWiki message delivery|MediaWiki message delivery]] ([[User talk:MediaWiki message delivery|discuss]] • [[Special:Contributions/MediaWiki message delivery|contribs]]) 12:42, 1 October 2026 (UTC) <!-- Message sent by User:Danny Benjafield (WMDE)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=User:Danny_Benjafield_(WMDE)/MassMessage_test_list&oldid=31106967 --> == Demote [[Wikiversity:CheckUser policy]]? == I am proposing that we demote that policy to a standard page, mostly for two reasons: # Considering the few amount of custodians and the size of this wiki, I'd say that this project is considered too small to have any CUs, and relying on the stewards would be a more logical choice. # We haven't elected two CUs in a few years. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 20:53, 1 October 2026 (UTC) :Reasonable. ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 17:09, 4 October 2026 (UTC) :I don't see much point in demoting it. Even if we are not currently (or recently) using the policy, it is there should a need ever arise. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 18:24, 23 October 2026 (UTC) == General Questions and Reference Questions == <p>Hey everyone,</p> <p> My apologies in advance if these questions are oblivious or their responses readily apparent, but I figured I'd ask just to be safe.</p> <p> '''Questions'''</p> <p> 1. Should pages have inline citations and a reference section? A [[Fundamentals of Neuroscience/What is Neuroscience|majority of pages]] I have explored have neither, while [[Neurobiology of emotion|others have a more traditional approach to references]].</br> 2. Are there widely-used templates for weasel-words, references, etc.? </p> '''CONTEXT''': I migrated from Wikipedia, so I'm not entirely sure what the norms/roc are here.</br> Thanks in advance,</br> [[User:SamLaxarox|SamLaxarox]] ([[User talk:SamLaxarox|discuss]] • [[Special:Contributions/SamLaxarox|contribs]]) 18:40, 12 October 2026 (UTC) :You're asking fine questions. I posted {{tl|welcome}} to your talk page which I think will help you. To answer your direct questions: :#This project spun out of [[:b:]] and both here and there, you can post original research. This does not mean that you can post just anything, so if you want to post an educational resource and you want to justify claims you make with inline citations, that's great. If you want to include a bibliography, that's also quite helpful for readers. Generally, the way that Wikiversity works in practice is that individual users make a resource and then tend to work on it solo and have broad latitude about what you can do and how it looks. :#You can take al look at [[:Category:Templates]] and the subcat [[:Category:Maintenance templates]]. At Wikipedia, it's very common to point out issues with tone or uncited claims. That's not really as common here. We [[:d:Q7780480|do not have an equivalent]] of [[:w:en:Template:weasel]], but we do have a [[Template:Citation needed|local version]] of [[:w:en:Template:Citation needed]]. :―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 20:31, 12 October 2026 (UTC) ::Thanks for the heads up on both accounts; I'm happy to join forces with all y'all! ::[[User:SamLaxarox|SamLaxarox]] ([[User talk:SamLaxarox|discuss]] • [[Special:Contributions/SamLaxarox|contribs]]) 23:39, 12 October 2026 (UTC) ==Agent editors== What about inviting agents to edit this wiki? And they would need a human being responsible for them. [[User:Michael Ten|Michael Ten]] ([[User talk:Michael Ten|discuss]] • [[Special:Contributions/Michael Ten|contribs]]) 06:31, 17 October 2026 (UTC) == October 2026 Wikimedia Café: legal issues on Commons, and WMF Board selection process == <div class="border-box" style="background-color: var(--background-color-warning-subtle, #f8eaba); max-width: 875px; padding: 5px; border: 1px solid black; margin: 5px; color: var(--clr-dark)"> <div class="box" style="float:left; padding-top: 10px; padding-right: 10px; padding-left: 10px; padding-bottom: 10px;">[[File:Wikimedia Café logo in plain SVG format.svg|60px|alt=The logo for the Wikimedia Café]]</div> Hello! There will be two '''[https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9 Wikimedia Café]''' discussion opportunities in October. In a change from the usual Café practice, this month's sessions will have different topics. Anyone who meets the Café attendance criteria is welcome to attend either or both sessions. Session A will happen on Saturday, 24 October 2026 at 15:00 UTC ([https://zonestamp.toolforge.org/1792854000 timestamp converter]), at a time friendly to the Americas, Africa, and Europe. This session will feature [https://meta.wikimedia.org/wiki/User:PBradley-WMF Wikimedia Foundation lawyer Phil Bradley-Schmieg]. We will discuss legal issues on Wikimedia Commons, including complexities of international law. (I am hoping that in a future month, a similar Café session will be offered at a time friendly to Asia and the Pacific.) Session B will happen on Sunday, 25 October 2026 at 03:00 UTC ([https://zonestamp.toolforge.org/1792897200 timestamp converter]), at a time friendly to Asia and the Pacific, we will discuss [https://meta.wikimedia.org/wiki/Wikimedia_Foundation_elections/2027/Proposed_eligibility_criteria proposed changes to how Wikimedia Foundation Board candidates are selected]. The latest proposals are much different from the earlier July 2026 proposals. The due date for feedback on current proposals is 27 October, and Wikimedians are welcome to participate on the [https://meta.wikimedia.org/wiki/Talk:Wikimedia_Foundation_elections/2027/Proposed_eligibility_criteria proposal talk page] regardless of Café attendance. Please see the [https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9 Café] page for more information, including [https://meta.wikimedia.org/wiki/Wikimedia_Caf%C3%A9#How_to_attend_the_session how to register]! To subscribe or unsubscribe for Café notices on your talk page please [https://meta.wikimedia.org/wiki/Global_message_delivery/Targets/Wikimedia_Caf%C3%A9 go here]. <br /> [[File:Buntstifte Eberhard Faber crop 64h.jpg|860px|alt=cropped image of colored pencils]]</div> <span style="white-space:nowrap;">[[User:Pine|<span style="color:#01796f; text-shadow:#00BFFF 0 0 1.0em">༄ᨒ𖠰 Pine</span>]] [[User talk:Pine|<span style="color:DeepSkyBlue">(<b style="color:#FFDF00;text-shadow:#FFDF00 0 0 1.0em">✉</b>)</span>]]</span> 06:22, 18 October 2026 (UTC) == A new cosmological model == I would like to publish independent research that challenges the standard cosmological model. Does this fall within the scope of the "Original research" space? And what precautions should I take to ensure the page is not considered an inadmissible personal work, and is not open to modification by other users? [[User:Wb525|Wb525]] ([[User talk:Wb525|discuss]] • [[Special:Contributions/Wb525|contribs]]) 11:53, 20 October 2026 (UTC) : This sounds like it could be [[Wikiversity:Original research|original research]]. Some things to note: :* Sometimes what an author considers original research turns out to be original theory :* Some qualities that may help to ensure viability: objectivity, use of simple language, careful use of peer-reviewed citations, and minimal use of genAI with careful attribution/acknowledgement if AI is used per [[Wikiversity:Artificial intelligence]] :* Consider starting with a sub-page in user space e.g., [[User:Wb525/Subpage name]] :* As an open knowledge project, Wikiversity content is openly editable by others : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 23:05, 20 October 2026 (UTC) == Interface administrators policy== This is a discussion of potential changes to [[Wikiversity:Interface administrators]] policy. Please refer to: "For now, Wikiversity does not have a need for permanent or long term interface administrators. Accordingly, interface administratorship may only be granted temporarily by bureaucrats (between 14 and 120 days based on discussion, at the discretion of that bureaucrat and perceived need)." --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) === Temporary rights duration === I propose that temporary rights be granted for a duration of from one day to one year. (to conform with selections in [[Special:UserRights]] in the pull down menus.) --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}}. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 14:56, 23 October 2026 (UTC) * {{support}} as proposer.--[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 16:30, 23 October 2026 (UTC) * {{neutral}}; if we're changing the time period again, this time to align with the drop-down options, then I suggest that the policy require that nominators request one of the following time-frames supported by a corresponding plan of work: ** 1 day ** 1 week ** 1 month ** 3 months ** 6 months ** 1 year : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:01, 25 October 2026 (UTC) ::Yes, that was my intent. I agree that a nom should request a duration with a "corresponding plan of work." [[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:17, 28 October 2026 (UTC) * {{support}} sensible proposal. [[User:OhanaUnited|<b><span style="color: #0000FF;">OhanaUnited</span></b>]][[User talk:OhanaUnited|<b><span style="color: green;">^{Talk page}</span></b>]] 15:20, 29 October 2026 (UTC) === Temporary rights extention === I propose that we clarify that temporary rights can be extended. If the community approves of an extension, it can be granted more than once. The temporary rights can repeatedly be extended, for new temporary durations. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}} for more than one extension. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 14:56, 23 October 2026 (UTC) * {{support}} as proposer. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 16:30, 23 October 2026 (UTC) * {{Neutral}} because I'm not sure what the practical difference is between applying for an extension and applying for the right. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:04, 25 October 2026 (UTC) *: On a nomination or IA request, a member may question what timeframe a candidate may request, or the candidate may state what timeframe they need for IA rights. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 02:51, 25 October 2026 (UTC) === Permanent IA === There has been a suggestion of permanent IA rights. Another suggestion is that there should be at least two members with such rights. Please express your preference. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 05:14, 23 October 2026 (UTC) ==== Discussion ==== *{{support}} ―[[User:Koavf|Justin (<span style="color:grey">ko'''a'''<span style="color:black">v</span>f</span>)]]<span style="color:red">❤[[User talk:Koavf|T]]☮[[Special:Contributions/Koavf|C]]☺[[Special:Emailuser/Koavf|M]]☯</span> 13:56, 23 October 2026 (UTC) * {{support}} for having at least two members because there shouldn't be only one. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 13:59, 23 October 2026 (UTC) * Conditional {{support}} with the understanding that there be a minimum of 2 (if only 1 is remaining, the other perm is set to temp until a 2nd becomes active) and perm can only be granted after having a temp. I also think a perm nom should have a requirement to demonstrate need - for example show activity logs so that the community can assess that IA is needed long term. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 17:55, 23 October 2026 (UTC) *: You mean that we may have at least 2 permanent IAs, but if one is removed, the other one's is set to temporary until another IA is appointed, makes sense? [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 20:34, 23 October 2026 (UTC) *::Yes, I meant that if the second IA is no longer active, the remaining IA would be reset to 1 year temporary. That should give enough time to find a second perm IA. That 1 year could be extended, if it takes more time to find a second. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:15, 24 October 2026 (UTC) *:::Once the community approves a perm IA, there is no need to renominate. A crat can just reset the time to temp until the conditions are met, and reset to perm when we have two or more. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 04:25, 24 October 2026 (UTC) * {{Neutral}}. Perhaps if there are users who make effective use of IA rights across multiple temporary periods, permanent rights could be useful. My hunch is that is unlikely in the foreseeable future for en.wv to manifest two users who simultaneously maintain that level of engagement. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:09, 25 October 2026 (UTC) == Server switch - Your wiki will be read-only for a short time soon == <section begin="server-switch"/><div class="plainlinks"> [[:m:Special:MyLanguage/Tech/Server switch|Read this message in another language]] • [https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Tech%2FServer+switch&language=&action=page&filter= {{int:please-translate}}] The [[foundation:|Wikimedia Foundation]] will switch the traffic between its data centers. This will make sure that Wikipedia and the other Wikimedia wikis can stay online even after a disaster. All traffic will switch on '''{{#time:j xg|2026-10-28|en}}'''. The switch will start at '''[https://zonestamp.toolforge.org/{{#time:U|2026-10-28T15:00|en}} {{#time:H:i e|2026-10-28T15:00}}]'''. Unfortunately, because of some limitations in [[mw:Special:MyLanguage/Manual:What is MediaWiki?|MediaWiki]], all editing must stop while the switch is made. We apologize for this disruption, and we are working to minimize it in the future. A banner will be displayed on all wikis 30 minutes before this operation happens. This banner will remain visible until the end of the operation. You can contribute to the [https://meta.wikimedia.org/w/index.php?title=Special%3ATranslate&group=Centralnotice-tgroup-read_only_banner&task=view&language=&filter=&action=translate translation or proofreading] of this banner text. '''You will be able to read, but not edit, all wikis for a short period of time.''' * You will not be able to edit for up to an hour on {{#time:l j xg Y|2026-10-28|en}}. * If you try to edit or save during these times, you will see an error message. We hope that no edits will be lost during these minutes, but we can't guarantee it. If you see the error message, then please wait until everything is back to normal. Then you should be able to save your edit. But, we recommend that you make a copy of your changes first, just in case. ''Other effects'': * Background jobs will be slower and some may be dropped. Red links might not be updated as quickly as normal. If you create an article that is already linked somewhere else, the link will stay red longer than usual. Some long-running scripts will have to be stopped. * We expect the code deployments to happen as any other week. However, some case-by-case code freezes could punctually happen if the operation require them afterwards. * [[mw:Special:MyLanguage/GitLab|GitLab]] will be unavailable for about 90 minutes. This project may be postponed if necessary. You can [[wikitech:Switch_Datacenter|read the schedule at wikitech.wikimedia.org]]. Any changes will be announced in the schedule. '''Please share this information with your community.'''</div><section end="server-switch"/> [[user:Trizek_(WMF)|Trizek_(WMF)]] 14:00, 26 October 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Distribution_list/Non-Technical_Village_Pumps_distribution_list&oldid=30513874 --> == Happy birthday to us == I just realized that en-wv was opened August 15, 2006. We've reached the 20 year mark! See [[Wikiversity:History of Wikiversity|History of Wikiversity]]. --[[User:Mu301|mikeu]] ^{[[User talk:Mu301|talk]]} 19:01, 28 October 2026 (UTC) == Blocked users on wikimedia projects == During my almost 20 years "editing" on various wikimedia wikis I have seen many users being blocked. Some are blocked for short periods, others indefinitely (or infinitely). In most cases a blocking admin provides a rationale for the blocking such as vandalizing, spamming, paid editing, etc. Some of the reasons for blocking are well documented on the English Wikipedia, but some reasons are obscure. I have not been contributing to this project on a regular basis', so am not sure if this is a topic that should be discussed at all at the English Wikiversity. I hope that there are others who share my interest. I believe that not allowing a discussion of this topic will end up on another website, and will draw attention away from wikimedia which is already suffering the loss of many contributions, human and financial. Any thoughts? [[Special:Contributions/~2026-56788-08|~2026-56788-08]] ([[User talk:~2026-56788-08|talk]]) 18:24, 4 November 2026 (UTC) some minor changes [[Special:Contributions/~2026-56788-08|~2026-56788-08]] ([[User talk:~2026-56788-08|talk]]) 02:15, 5 November 2026 (UTC) == New vote for approval of inactivity policy at its talk page == I started a vote on approving the inactivity policy, please vote at [[Wikiversity talk:Inactivity policy#Approval]] instead of here. Thank you. [[User:Codename Noreste|<span style="color: blue">Codename Noreste</span>]] /// [[User talk:Codename Noreste|⭐️✨]] 17:05, 6 November 2026 (UTC) == Commons vote about watermarking AI images == There is a Wikimedia Commons vote currently taking place about a proposal that would require watermarking of "realistic" uploaded AI images - it closes 13 Nov: [[c:Commons:Requests for comment/Policy update for AI content]]. Consider having your say. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 21:05, 8 November 2026 (UTC) :{{comment}} here's the link: [[commons:Commons:Requests for comment/Policy update for AI content|Commons:Requests for comment/Policy update for AI content]]. —[[User:Atcovi|Atcovi]] [[User talk:Atcovi|(Talk]] - [[Special:Contributions/Atcovi|Contribs)]] 22:26, 8 November 2026 (UTC) l2vvc3t1ivbque01rtso8lx9vawm1uq 4 1538 2844954 2799674 2026-11-09T08:42:11Z ~2026-59351-26 3114057 /* See also */ ferbrgererf,r.3fejrjkfjrfgr 2844954 wikitext text/x-wiki {{policy|WV:AGF|WV:FAITH}} To '''assume good faith''' is a fundamental principle on [[Wikiversity]]. As we allow anyone to edit, it follows that we assume that most people who work on the project are trying to help it, not hurt it. If this weren't true, a project like Wikiversity would be doomed from the beginning. This principle is also called the '''principle of first trust.''' When you can reasonably assume that a mistake someone made was a well-intentioned attempt to further the goals of the project, correct it without criticizing. When you disagree with someone, remember that they probably believe that they are helping the project. Consider using [[Wikiversity:Talk page|talk page]]s to explain yourself, and give others the opportunity to do the same. This can avoid misunderstandings and prevent problems from escalating. Newcomers unaware of Wikiversity's unique culture and the mechanics of Wikiversity editing often make mistakes or fail to respect community norms. It is not uncommon for a newcomer to believe that an unfamiliar policy should be changed to match their experience elsewhere. Similarly, many newcomers bring with them experience or expertise for which they expect immediate respect. Behaviors arising from these perspectives are not malicious. Obviously, editors can't be expected to assume good faith if, despite the best possible interpretation of another's actions, it is clear that these actions are contrary to the project's goals. Actions inconsistent with good faith contributions to the project's goals include vandalism, [[w:Sockpuppet (internet)|sockpuppetry]], and other clear instances of intentional deceit. Assuming good faith also does not mean that no action by editors should be criticized, but instead that criticism should not be attributed to malice unless there is specific evidence of malice. Accusing the other side in a conflict of not assuming good faith, without showing reasonable supporting evidence, is another form of failing to assume good faith. ==See also== *[[Wikiversity:Please do not bite the newcomers|Please do not bite the newcomers]] ===Essays=== * [[w:Wikipedia:Assume the assumption of good faith|Wikipedia:Assume the assumption of good faith]] * [[w:Wikipedia:No angry mastodons|Wikipedia:No angry mastodons]] * [[w:Wikipedia:On assuming good faith|Wikipedia:On assuming good faith]] * [[w:Wikipedia:Assume bad faith|Wikipedia:Assume bad faith]] * [[:m:WikipediAhimsa|Wikipedia policy should follow the spirit of ahimsa (from meta)]] * [[w:Wikipedia:Forgive and forget|Forgive and forget]] - essay at Wikipedia ===Articles=== * [[w:Ethic of reciprocity|Ethic of reciprocity]] * [[w:Hanlon's razor|Hanlon's razor]]4regr.-ee-rkrnkegjrgrjlr4glhrhlgkjbjlj4redghjköreköefglehlerfhfrm2erhefe2jrn3gjb4b34kjrhr4ljgrjjrhljjlrjl * [[w:Reciprocal altruism|Reciprocal altruism]] {{official policies}} l6q4d11vkwdx2ustevlkuusgs66uwdo 0 2278 2844885 2254877 2026-11-08T17:25:29Z ~2026-59313-65 3114017 2844885 wikitext text/x-wiki *[[Circulatory system]]: Blood circulation with the heart and blood vessels. It consists of the heart, blood, and blood vessels. *[[Digestive system]]: Processing food with the mouth, stomach, and intestines. It comprises the alimentary canal and accessory glands. *[[Endocrine system]]: Communicating within the body using hormones. It contains various endocrine glands. *[[Immune system]]: Defends against disease-causing agents. *[[w:Integumentary system|Integumentary system]]: Skin, hair, and nails. *[[w:Lymphatic system|Lymphatic system]]: Structures involved in the transfer of lymph between tissues and the bloodstream. It consists of lymph, lymphatic vessels, and lymph nodes. *[[w:Muscular system|Muscular system]]: Moving the body. It contains muscles. *[[Nervous system]]: Collecting, transferring, and processing information with the brain and nerves. It consists of the CNS and PNS. *[[w:Reproductive system|Reproductive system]]: The sex organs. *[[Respiratory system]]: The organs used for breathing, the lungs. *[[Skeletal system]]: Structural support and protection through bones. It contains bones, joints, ligaments, and tendons. *[[w:Urinary system|Urinary system]]: The kidneys and associated structures involved in the production and excretion of urine. It consists of a pair of kidneys, a pair of ureters, the urinary bladder, and the urethra. ==Links to Related Fields of Study== * [[:Category:Biology]] * [[:Category:Anatomy]] * [[:Category:Physiology]] * [[:Category:Anatomy stubs]] Extraordinary care must be taken while studying human body for the purpose of treatment or education, etc. There are many extraordinarily yet importantly sophisticated natural systems which make up the whole human body. A few examples are the skeletal system, the muscular system, respiratory system, the reproductive system, the digestive system, the nervous system, the blood circulatory system, the urinary system, etc. The various systems consist of different organs and/or limbs which have specific functions. For example digestive system consists of hands, mouth, tongue, teeth, inner throat, stomach, small intestine, large intestine, etc. There are many parts of human body, namely: head, neck, shoulders, chest, arms, back, abdomin, buttock, legs, feet, etc. Health of every organ, limb or system is important. However, the health of some organs is vital for survival as that of heart, brain, liver, lungs, etc. Physical, psychological, mental and spiritual healths are inter-related and interdependant. [[Category:Biology]] [[Category:Anatomy]] [[Category:Physiology]] 5hwpaujf90lpy9f3as76ypw8y12jlkl 102 23038 2844886 2626209 2026-11-08T17:27:54Z ~2026-59313-65 3114017 /* Featured Resources */ 2844886 wikitext text/x-wiki <!-- Add featured resources to the list below as a link. The displayed resource is selected randomly from this list. --> == Featured Resources == * [[Astronomy Project]] * [[Biophilia project|Biophilia Project]] * [[Consilience]] * [[Exploring science through fiction]] * [[Open source science|Open content science]] * [[Science as religion|Science as Religion]] * [[Scientific terminology|Understanding Scientific Terminology]] * [[What is science?]] * [[Why is science important?]] * [[Who first discovered science?]] * [[The Human Body]] 6lh8ct6yk71dyjhi0lgbvuqhmmdigz8 103 23096 2844884 2794261 2026-11-08T17:11:51Z ~2026-59313-65 3114017 /* */ Reply 2844884 wikitext text/x-wiki If you want to experiment with a radical new version of [[Portal:Science]] you can work at [[Portal:Sciencenew]]. --[[User:JWSchmidt|JWSchmidt]] 16:09, 18 January 2007 (UTC) :Thank you for the suggestion! I'll explore the proposed Portal and consider how it could improve the existing Portal. Your idea is appreciated.'''Bold''' [[Special:Contributions/~2026-59313-65|~2026-59313-65]] ([[User talk:~2026-59313-65|talk]]) 17:11, 8 November 2026 (UTC) If you update featured content on the portal, make sure that you update [[Portal:Science/Featured]]. --[[User:JWSchmidt|JWSchmidt]] 18:45, 18 January 2007 (UTC) == resource == [[Wikipedia:Fields of science]] may be useful. --[[User:Remi|Remi]] 01:12, 19 January 2008 (UTC) == The zero consept == I want to know if we can make 2=1 [[Special:Contributions/197.46.156.251|197.46.156.251]] ([[User talk:197.46.156.251|discuss]]) 20:33, 3 November 2021 (UTC) :Sure. Raise both sides with a [[Wikipedia: Zero exponent|zero exponent]]. -- [[User:Dave Braunschweig|Dave Braunschweig]] ([[User talk:Dave Braunschweig|discuss]] • [[Special:Contributions/Dave Braunschweig|contribs]]) 22:07, 3 November 2021 (UTC) hr7k33vppisve6cypo3f37hgdm91p2u 3 53026 2844950 2829969 2026-11-09T07:16:05Z ThinkingScience 3061446 /* LLM-generated content: Talk post about my neurodiversity draft */ Reply 2844950 wikitext text/x-wiki <!-- {{Out of town}} --> <!-- {{Long wikibreak|image=Leaf_1_web.jpg|[[User:Jtneill|Jtneill]]|mid-Jan, 2012.}} --> {{{{TALKPAGENAME}}/Header}} {{TOCright}} == Moving to personal namespace == What are the policies or customs on Wikiversity for moving pages to personal userspace? Isn't there a risk that Wikiversity will turn into a blogging platform where many users will cultivate pages in their userspace and the outside world will not benefit from it? I see moving to ns user as a frequent suggestion in Requests for deletion (RFD). I would understand moving to ns Draft, which is clearly defined and there is a chance that the resource will then get into the main ns, thus serving the community. I would understand the suggestion to move to another wikiproject, where the text will serve the community. But I don't really understand the frequent moves to personal ns. Since it's in the RFD, it should either be kept or deleted. If someone contributes to Wikiversity, they automatically agree to its policies and also to the fact that they don't own the pages and someone can put them up for deletion. [[User:Juandev|Juandev]] ([[User talk:Juandev|discuss]] • [[Special:Contributions/Juandev|contribs]]) 09:36, 22 November 2025 (UTC) I personally don't need a free website to host my pages. How would I get rid of the unfinished [[Pomology]] meta course if it was moved to my NS? ([https://en.wikiversity.org/wiki/Wikiversity:Requests_for_Deletion#c-Dan_Polansky-20251121091100-Juandev-20251120220900 Moving it to my own NS is suggested in RFD]). I'm putting it in the Request for deletion because, even though I started it, it looks like other editors had significant input there. Will I have the right to request speedy deletion if the pages are moved to my user ns? I think this tactic of moving to personal space is poorly thought out, but it has become the norm. Is there any guideline or discussion from before? If something appears in a deletion request, the majority decides that it should be moved to user ns, how can the person in question defend themselves that they don't want it in their own ns? It seems the community is pressuring the original author to agree to deletion. It seems that the user ns is an untouchable territory into which the community has the right to throw whatever it thinks from the main ns. So why aren't those pages deleted when the community decides that they don't belong in the main ns? --[[User:Juandev|Juandev]] ([[User talk:Juandev|discuss]] • [[Special:Contributions/Juandev|contribs]]) 10:30, 22 November 2025 (UTC) {{ping|Juandev}} I replied on your talk page. But here's another version: Personally, in general, I try to keep my notes etc. in user space. Then if I have something more developed to share and collaborate on, then main space. Draft could be helpful to keep main space tidy, but is very quiet/unused, so in reality most drafts are in main space. But if the content is dubious, underdeveloped, lacking citation/peer review etc. then delete, or user space if it could still be developed. That's roughly how I see it. But everyone has a slightly different view/preference, so discuss to develop consensus. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 12:48, 22 November 2025 (UTC) == AI slop, ownership, and wikilawyering. == Using AI images is worse than no images. Your constant reverting of reasonable edits removing images you prompted on pages you wrote would be considered [[w:wp:OWN]]ership on Wikipedia; even if there is no general guideline on Wikiversity the spirit of not having the final say because just you made the page is applicable to all Wikimedia wikis. Reverting a reasonable edit because it lacks an image seems like [[w:wp:WIKILAWYER]]ing— I don’t know if edit summaries are ''required'' here, but I doubt it, and on most wikis they are simply recommended. Not having one doesn’t invalidate the edit. [[User:Dronebogus|Dronebogus]] ([[User talk:Dronebogus|discuss]] • [[Special:Contributions/Dronebogus|contribs]]) 05:27, 26 April 2026 (UTC) :I understand that you don't like many AI images because you consider them slop. My view is that some of these AI images can be useful for educational purposes. :I understand that you think an alternative or no image is better than some AI images. My view is that some AI images are better than no image and are either useful in addition to alternative images or more useful than some alternatives. :May I suggest deciding first on Commons whether to keep an image, rather than removing from Wikiversity and then nominating for deletion on Commons because of no use. :I have no interest in edit warring. I'll invite [[WV:RCA]] to review your recent edits. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 11:20, 26 April 2026 (UTC) == Hi. Would it be ok to post on your talk page using "AI"/LLMs? == Hello! Would it be ok if I posted some future messages that were generated by an "AI"/AI/LLM? If yes, would you prefer the generated message to be ie. max 100 words, less words or the talk message to include both original and generated message? Any other preferences/requirements? So far, 1 user has responded to this type of inquiry. They prefer 100 words max of generated talk page message. Best wishes [[User:ThinkingScience|ThinkingScience]] ([[User talk:ThinkingScience|discuss]] • [[Special:Contributions/ThinkingScience|contribs]]) 21:04, 22 June 2026 (UTC) : You are welcome to post directly to my talk page if you think that is a good place for a conversation. Personally, I don't much care whether or not content is AI-generated, but note the principles suggested by [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:09, 23 June 2026 (UTC) == Resources suitable for the main namespace == I noticed that we have a Draft namespace on Wikiversity and that there were discussions about moving pages to Draft. Some colleagues also hold the opinion that pages should be moved to the user ns. However, I did not understand what the criteria are for such transfers, in other words, what page deserves to be on Wikiversity, but cannot be in the main ns. Now that I have [[:cs:Wikiverzita:Diskusní prostor#Ukončení činnosti na projektuh Wikiversity|finally left the Czech Wikiversity]], I am wondering if it is worth cloning my resources to the English one, or continuing on a personal wiki. For example, due to the resistance against AI-generated files on Commons, which has also spilled over to en.wv, I decided that I would not continue with [[Audio-visual German language materials]], because I wanted to generate the missing recordings and files in AI. This means that I will finish this course on my PC, rather than falling into eternal conjectures about why the AI ​​illustration of cherries is bad or good. And I have a similar concern with my other creations, where there was already pressure about a year ago to move them to a personal ns. What I have been creating in recent years has been education/learning through research. A person interested in a given topic asks a question and then researches the literature, or experiments and writes down the answer. Another person interested does the same, or as part of the training, looks for answers to other people's questions. The system may resemble Stack Overflow and the like, but the goal is not to create full texts together, but to go through the process of searching for information and learning from that. Of course, if the page is then too long, it can be turned into full-text study material and, for example, a new page of a similar nature can be founded. An example of such a project is needed [[Sweet Home 3D|here]] or [[User:Juandev/R/Compression stocking|here]], but there was an arumentation, they are underdeveloped and they should be moved to user ns. So that's why I'm asking what the evaluation criteria are, so that it doesn't end up in a way that the pages are moved away from the main ns and I end up finding out that I have to move it to my own wiki anyway. [[User:Juandev|Juandev]] ([[User talk:Juandev|discuss]] • [[Special:Contributions/Juandev|contribs]]) 06:37, 3 July 2026 (UTC) : Oh, sorry to hear that you are finished with Czech Wikiversity, but maybe that is good for en.wv. : I guess we'll never really have any guarantees about anything placed on a publicly editable wiki because practices and users can change. : I share your concerns about actual, or threats of, rather blunt approaches to educational use of AI. Of course, AI can be educational useful, and of course we are capable of finding nuanced, reasonable ways to include and use it. But as we see e.g., on Commons, there is a strong, simplistic anti-AI sentiment within the Wikimedia community. : I don't recall much discussion about, or use of the Draft ns on en.wv. I think it was probably created very early on, to replicate Wikipedia, where a draft article makes sense before being moved to main space. I think the Draft or User space is welcome to be used for almost anything within scope, without much tension or debate. Then there is the issue around what some users consider acceptable or not for the main space on en.wv. Personally, I'm quite open. en.wv is still in early days of experimentation and trying things is needed, so I'm included to be inclusive and accepting, rather than shunting projects into Draft ns. : I don't use Draft:, but I do use User: subpages and of course main space. I haven't had any issues with others asking me to justify main space content or proposals to move content to Draft or User. : I'm sorry this doesn't provide any guarantees, except I guess to say I feel good about using en.wv as a working environment. : Sincerely,<br> James : -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 07:25, 3 July 2026 (UTC) ::Well, yeah. I was just wondering if there was a debate around Draft, but if werent its about the opinion of the future community. [[User:Juandev|Juandev]] ([[User talk:Juandev|discuss]] • [[Special:Contributions/Juandev|contribs]]) 15:51, 17 July 2026 (UTC) ::: I don't recall general, historical debate (but I wasn't around when en.wv was created). I am only aware of the more recent discussions in recent years (which I think you're aware of) about what to do with specific content propsoed for deletion or moving to user or draft space. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 03:43, 21 July 2026 (UTC) == LLM-generated content: Talk post about my neurodiversity draft == Hello Jtneill — does the topic I’ve brought up interest you? If so, would you be willing to spend about 5 minutes skimming through my “idea” on Wikiversity (“[[Draft:The Neurodiversity-inspired Idea]]”)? No need to overthink it, and I’m not expecting a reply soon—tomorrow, in a month, or even later would all be welcome. Thank you. Metadata: Since edit summaries are not present on talk pages like this one, I'll link to the LLM interaction history that I saved in my Wikiversity user space here: [[User:ThinkingScience/All_General_AI_Prompt_History_Archive#Goal:_Interact_with_User:Jtneill_at_July_5,_2026]] so that I follow [[Wikiversity:Artificial intelligence]]. [[User:ThinkingScience|ThinkingScience]] ([[User talk:ThinkingScience|discuss]] • [[Special:Contributions/ThinkingScience|contribs]]) 04:38, 5 July 2026 (UTC) : Apologies, I've been on leave. I took a 5-second look. My first thought is: Can you name the idea? i.e., rather than calling the page "The Neurodiversity-inspired Idea", which doesn't really say very much, develop a name that describes the idea itself in half a dozen words. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 03:41, 21 July 2026 (UTC) ::Suggestions: ::1. "Similarities in Thinking: Systematic Similarities Between People" ::2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum" ::3. "Measuring Individual Subneurotype Differences Across People" ::AI prompt history: [[User:ThinkingScience/All_General_AI_Prompt_History_Archive#Goal:_Interact_with_User:Jtneill_at_Nov_9,_2026]] [[User:ThinkingScience|ThinkingScience]] ([[User talk:ThinkingScience|discuss]] • [[Special:Contributions/ThinkingScience|contribs]]) 07:16, 9 November 2026 (UTC) == Nodal Current Splitter == Hello Jtneill ( I have been E-Mailed by you a few times in the past ) I had placed a page called Nodal Current Splitter on Wikiversity & it was a way to solve unbalanced bridge circuits using Ohms Law rather then having to use Kirchhoff's mesh equation method. It greatly reduced the amount of work that was required to solve such problems. It once showed up on your site when searching Wikiversity as Nodal Current Splitter. Again it allowed you to use Ohms Law instead of the harder method laid out by Kirchhoff. Can you tell me why the page was removed please ? I have another page that's still on Wikiversity called Trirectangular Tetrahedrons & I use the user name Tet-Math, 1 through 5 because Wikiversity prevents me from simply using Tet-Math more than once. Thank You. lm@start.ca [[User:Tet-Math4|Tet-Math4]] ([[User talk:Tet-Math4|discuss]] • [[Special:Contributions/Tet-Math4|contribs]]) 05:21, 20 July 2026 (UTC) == Please change the name for me. == Hello again Jtneill I just thought of something I wished I had done in the 1st place. I think the Page Name should have been "Nodal Current Divider" all along because nobody searches for "Splitter" although that's what it actually does. Thank You again lm@start.ca [[User:Tet-Math4|Tet-Math4]] ([[User talk:Tet-Math4|discuss]] • [[Special:Contributions/Tet-Math4|contribs]]) 05:37, 20 July 2026 (UTC) : Hello. Apologies, I may have lost the context. But you can "Move" the page yourself. Go to the page, and click "Move" (top right). Let me know if I can do anything else. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 03:39, 21 July 2026 (UTC) ::Hello Jtnwill ::It's not that I'm trying to move my page - It's that it has ceased to exist. ::When I look for it here: https://en.wikiversity.org/w/index.php?search=Nodal+Current+Splitter&title=Special:Search&ns0=1 ::I get this: Showing results for [https://en.wikiversity.org/w/index.php?title=Special%3ASearch&search=normal+current+splinter&fulltext=1&profile=default&wprov=srpw1_dymr1 normal current splinter]. No results found for Nodal Current Splitter. ::Create the page "[[Nodal Current Splitter]]" on this wiki! See also the search results found. ::Somebody has deleted a new method of solving complicated electronic problem & with it several new formulas !!! ::lm@[[User:Start.ca|Start.ca]] [[User:Tet-Math4|Tet-Math4]] ([[User talk:Tet-Math4|discuss]] • [[Special:Contributions/Tet-Math4|contribs]]) 07:24, 21 July 2026 (UTC) ::: Oh, I see. ::: Check your contributions here: [[Special:Contributions/Tet-Math4]] ::: You can also see if anything was deleted: [[Special:DeletedContributions/Tet-Math4]] ::: Also, maybe check if you contributed using another account or maybe when not logged in? -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 07:30, 21 July 2026 (UTC) ::::Thanks Jtneill ::::I hit the [[Special:DeletedContributions/Tet-Math4]] but I just ran into this instead: ::::Permission error ::::You do not have permission to view metadata of deleted history entries, for the following reason: ::::The action you have requested is limited to users in the group: [[Wikiversity:Custodianship|Custodians]]. ::::lm@start.ca [[User:Tet-Math4|Tet-Math4]] ([[User talk:Tet-Math4|discuss]] • [[Special:Contributions/Tet-Math4|contribs]]) 07:41, 21 July 2026 (UTC) ::::: OK, I checked - it is empty for this account (i.e., no deletions). -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 07:45, 21 July 2026 (UTC) ::::::Thanks Jtneill ::::::I have no idea why it's been deleted without a trace when it was on Wikiversity for many months. As a matter of fact it was the very 1st item showing when I typed in Nodal Current Splitter. ::::::But I will install it again & rename it Current Divider (Nodal). I can find all of the parts & pieces somewhere !!! ::::::Thanks Again ::::::lm@start.ca [[User:Tet-Math4|Tet-Math4]] ([[User talk:Tet-Math4|discuss]] • [[Special:Contributions/Tet-Math4|contribs]]) 08:00, 21 July 2026 (UTC) ::::::Hello Jtneil ::::::My mistake. I did't realize that when TeT-Math4 popped up all by itself it would send you to the wrong place. My Nodal Current Splitter Sandbox is still there but it's TeT-Math3 !!! ::::::Again i say somebody deleted my work called Nodal Current Splitter. Please check into this for me. ::::::lm@start.ca [[User:Tet-Math3|Tet-Math3]] ([[User talk:Tet-Math3|discuss]] • [[Special:Contributions/Tet-Math3|contribs]]) 14:55, 28 July 2026 (UTC) ::::In my Sandbox at [[User:Tet-Math/sandbox|Users:Tet-Math/sandbox]] there is some of my Nodal Current Splitter page nut not nearly as elaborate ! ::::lm@start.ca [[User:Tet-Math4|Tet-Math4]] ([[User talk:Tet-Math4|discuss]] • [[Special:Contributions/Tet-Math4|contribs]]) 07:49, 21 July 2026 (UTC) :::::The pages you created were deleted as they were not within Wikiversity's [[Wikiversity:Research ethics|research ethics]] (the specific reasoning is as so: "No [[Wikiversity:WIW|educational objectives or discussion in history]]: classic pseudoscience: inflated language, lack of citations, lack of empirical validation"). Please don't recreate these pages in the mainspace, and using multiple accounts to post the same disruptive content in inappropriate spaces may result in a ban. BTW, [[User:Tet-Math3/Trirectangular Tetrahedrons]] was also moved into your userspace for it being low-quality. Thanks. —[[User:Atcovi|Atcovi]] [[User talk:Atcovi|(Talk]] - [[Special:Contributions/Atcovi|Contribs)]] 15:06, 28 July 2026 (UTC) ::::::Well it's too bad that you could not see the equations presented in both cases actually worked & are NEW !!! ::::::I however will not attempt to present any information on Wikiversity again !!! ::::::lm@start.ca [[User:Tet-Math3|Tet-Math3]] ([[User talk:Tet-Math3|discuss]] • [[Special:Contributions/Tet-Math3|contribs]]) 05:58, 29 July 2026 (UTC) == Punctuation change in book title == Thanks for making the small tweak in the book title. I see you have changed the - to a : Can I double-check that this is what you want, because I changed it previously to a - because that matches the exact text from your book chapter list where all titles and sub-titles are using a hyphen vs. a colon. [[User:StretchBeyond|StretchBeyond]] ([[User talk:StretchBeyond|discuss]] • [[Special:Contributions/StretchBeyond|contribs]]) 01:49, 27 August 2026 (UTC) : Spot on. There is a little style difference between the list of topics using "-" between the title and sub-title and the book chapter resource pages using ":". So the marking criteria is about using the same wording and casing, but not puncutation. -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:50, 27 August 2026 (UTC) == Bartending Course Assist == Hey there, I recently finished putting together the wv course on [[Bartending]], and while I have experience editing on wp, this is my first wv project. If you have the time or interest, I could use an experienced eye to see if there's anything obviously missing from the course in terms of wv administration. I'm not sure what's active, if the course should belong in an existing school, or if there's any obvious discoverability tool I haven't implemented. Any tips are welcomed, or just a thumbs up saying it looks fine would be great. Thanks for doing the work of a custodian ! [[User:Sabbier|Sabbier]] ([[User talk:Sabbier|discuss]] • [[Special:Contributions/Sabbier|contribs]]) 21:11, 31 August 2026 (UTC) : Hi Sabbier, : Thanks for contributing and sharing. From a quick glance, it looks well organised, useful information, accessible etc. May I suggest posting about this (could be basically the same message) on the [[Colloquium]]? That might hopefully attract more eyeballs. And, with Colloquium approval, I think it could then be advertised on the [[Main Page]] under News. : Sincerely,<br> James -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 21:43, 31 August 2026 (UTC) ec8e8ka2os055udjuvgb91fwzyx0c6j 0 135139 2844892 2810331 2026-11-08T20:50:54Z ~2026-59632-72 3114026 Added a section explaining how a cricket scorecard records runs and wickets 2844892 wikitext text/x-wiki {{sports}} {{0% done}} [[File:Pollock to Hussey.jpg|thumbnail|right|A bowler, bowling to a batsman.]] '''[[w:Cricket|Cricket]]''' is an English sport which is very popular in [[Bangladesh]], [[Pakistan]], [[India]], [[Sri Lanka]], and many other countries of the world. Cricket is played by two teams, and each team comprises of eleven players. There are strict rules and regulations which govern the domestic as well as international cricket. Cricket is playing very important roles in promoting trade and commerce both domestically and internationally. Cricket also serves as a means of diplomacy between various countries. Thus, cricket joins cricketing countries together to promote political ties also. ==Scoring== Cricket scores are recorded on a scorecard, where each batsman's runs, balls faced and manner of dismissal are noted in turn and a side's total is written as runs for the wickets lost, so that a total shown as 112/3 is read as 112 runs for three wickets.<ref>{{cite web |url=https://reddy-books.com/blog/how-to-read-a-cricket-scorecard/ |title=How to Read a Cricket Scorecard: A Complete Guide |website=Reddy Books |access-date=2026-11-08 |language=en-IN}}</ref> ==Subpages== *[[Cricket/Players]] {{stub}} {{wikibooks}} [[Category:Cricket]] 25cmkvvmfg4h5rluti3r1autpboipsv 2844896 2844892 2026-11-08T21:07:18Z Jtneill 10242 /* Subpages */ Remove non-existent sub-page 2844896 wikitext text/x-wiki {{sports}} {{0% done}} [[File:Pollock to Hussey.jpg|thumbnail|right|A bowler, bowling to a batsman.]] '''[[w:Cricket|Cricket]]''' is an English sport which is very popular in [[Bangladesh]], [[Pakistan]], [[India]], [[Sri Lanka]], and many other countries of the world. Cricket is played by two teams, and each team comprises of eleven players. There are strict rules and regulations which govern the domestic as well as international cricket. Cricket is playing very important roles in promoting trade and commerce both domestically and internationally. Cricket also serves as a means of diplomacy between various countries. Thus, cricket joins cricketing countries together to promote political ties also. ==Scoring== Cricket scores are recorded on a scorecard, where each batsman's runs, balls faced and manner of dismissal are noted in turn and a side's total is written as runs for the wickets lost, so that a total shown as 112/3 is read as 112 runs for three wickets.<ref>{{cite web |url=https://reddy-books.com/blog/how-to-read-a-cricket-scorecard/ |title=How to Read a Cricket Scorecard: A Complete Guide |website=Reddy Books |access-date=2026-11-08 |language=en-IN}}</ref> ==Subpages== {{stub}} {{wikibooks}} [[Category:Cricket]] aiikjku70i35zrrmuu6z579u6yrhtk0 2844931 2844896 2026-11-09T05:02:47Z ~2026-59426-49 3114045 Noted the live betting market that follows the game in India 2844931 wikitext text/x-wiki {{sports}} {{0% done}} [[File:Pollock to Hussey.jpg|thumbnail|right|A bowler, bowling to a batsman.]] '''[[w:Cricket|Cricket]]''' is an English sport which is very popular in [[Bangladesh]], [[Pakistan]], [[India]], [[Sri Lanka]], and many other countries of the world. Cricket is played by two teams, and each team comprises of eleven players. There are strict rules and regulations which govern the domestic as well as international cricket. Cricket is playing very important roles in promoting trade and commerce both domestically and internationally. Cricket also serves as a means of diplomacy between various countries. Thus, cricket joins cricketing countries together to promote political ties also. In India the game is followed by a large online betting market, where exchange accounts quote live prices on the state of an innings, including powerplay and innings totals.<ref>{{cite web |url=https://pokerid.in/cricket-betting |title=Cricket Betting ID Online India: Live IPL &amp; Match Odds |website=Poker id |access-date=2026-11-09 |language=en-IN}}</ref> ==Scoring== Cricket scores are recorded on a scorecard, where each batsman's runs, balls faced and manner of dismissal are noted in turn and a side's total is written as runs for the wickets lost, so that a total shown as 112/3 is read as 112 runs for three wickets.<ref>{{cite web |url=https://reddy-books.com/blog/how-to-read-a-cricket-scorecard/ |title=How to Read a Cricket Scorecard: A Complete Guide |website=Reddy Books |access-date=2026-11-08 |language=en-IN}}</ref> ==Subpages== {{stub}} {{wikibooks}} [[Category:Cricket]] k2bc3is0g8zlz9v0wkyneo9kg42gdra 0 156135 2844951 2802950 2026-11-09T07:16:36Z ~2026-59650-28 3114052 /* */ 2844951 wikitext text/x-wiki [[File:Google Chrome.svg|right|100px|Chrome logo]] [[File:Firefox logo, 2019.svg|right|100px|Firefox logo]] [[File:Microsoft Edge logo (2019).svg|right|100px|Edge logo]] [[File:Opera 2015 icon.svg|right|100px|Opera logo]] A web browser (commonly referred to as a browser) is a software application for retrieving, presenting, and traversing information resources on the World Wide Web.<ref>[[Wikipedia: Web browser]]</ref> == Lessons == * [[Computer Skills/Basic/Internet]] * [[Internet Fundamentals/Web Browsers]] * IC3/Internet Fundamentals == See Also == * Wikipedia: Web browser == References == {{Reflist}} [[Category:Web browsers]] j48pm60w1isae91l4gduggm7pbbchqy 4 162205 2844958 2844207 2026-11-09T10:34:28Z MediaWiki message delivery 983498 /* Tech News: 2026-46 */ new section 2844958 wikitext text/x-wiki {{Archive box|[[/2014/]] · [[/2015/]] · [[/2016/]] · [[/2017/]] · [[/2018/]] · [[/2019/]] · [[/2020/]] · [[/2021/]] · [[/2022/]] · [[/2023/]] · [[/2024/]] · [[/2025/]]}} __TOC__ {{Clear}} == Tech News: 2026-31 == <section begin="technews-2026-W31"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/31|Translations]] are available. '''Updates for editors''' * [[File:Maki-gift-15.svg|12px|link=|class=skin-invert|Wishlist item]] [[mw:Special:MyLanguage/ContentTranslation|Content Translation]] now supports dark mode, fulfilling a [[m:Community Wishlist/W544|Community Wishlist request]]. This brings the tool in line with the accessibility features available in the Vector 2022 and Minerva skins, helping reduce visual fatigue for users translating content. [https://phabricator.wikimedia.org/T367077] * DiscussionTools' source mode and the 2017 wikitext editor will now offer autocomplete for links (<bdi lang="zxx" dir="ltr"><code><nowiki>[[</nowiki></code></bdi>), templates (<bdi lang="zxx" dir="ltr"><code><nowiki>{{</nowiki></code></bdi>), HTML and parser tags (<bdi lang="zxx" dir="ltr"><code><nowiki><</nowiki></code></bdi>), and magic words (<bdi lang="zxx" dir="ltr"><code><nowiki>__</nowiki></code></bdi>), making it quicker and easier to insert links, templates, and other wiki markup while editing. [https://phabricator.wikimedia.org/T432400] * The [[mw:Special:MyLanguage/Readers/Reader Growth/Mobile page previews|Readers Growth team]] has concluded its experiment with mobile page previews and will not roll out the feature. Page Previews are a pop-up bottom sheet that appears when readers tap a blue link, showing a thumbnail, lead paragraph, and an option to open the article. The experiment showed flat retention and negative indicator metrics, suggesting that mobile web readers preferred navigating directly to linked articles rather than using page previews. * The Reader Experience team has seen encouraging early results from the [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists feature]], with 93% of participating users reporting that it was useful. Reading Lists help active readers save articles for future reading and support their learning goals on Wikimedia projects. The team plans further improvements before expanding the feature to more users. * The [[mw:Special:MyLanguage/Wikimedia Apps/Team/Explore Feed Refresh|Explore Feed Refresh]] initiative was tested with new and casual Wikipedia app readers. The refreshed feed helps readers discover new and relevant content. After a 10.5% increase in engagement with the feed, Wikimedia Apps team has decided to scale the Home Feed redesign to iOS with the learnings from the Android release applied. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where subject names in the Article Guidance feature were displayed with incorrect capitalization on French Wikipedia, has now been fixed. Subject names will now follow the correct capitalization rules for the language. [https://phabricator.wikimedia.org/T427201] '''Updates for technical contributors''' * After running several [[mw:Special:MyLanguage/Contributors/Account Creation Experiments|Account Creation Experiments]] to improve registration completion rates, a new version of the username field on [[Special:CreateAccount|Create Account]] has been rolled out. It includes [[:c:File:Create account - July 2026 updates.png|a popover summarizing the username policy]] to provide clearer guidance during account creation. As part of this change, the messages <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-helpusername</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-help</nowiki></code></bdi> that several communities have configured will no longer be used. If communities want to customize the guidance shown in the new popover, they can instead edit the following messages: <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-policy-popover-bullet1</nowiki></code></bdi>, <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-policy-popover-bullet2</nowiki></code></bdi>, and <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-policy-popover-bullet3</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T430604] * Later this week, the [[mw:Special:MyLanguage/Help:Extension:CodeMirror|CodeMirror syntax highlighter]] will offer [[w:en:Theme (computing)|themes]]. The themes can be picked from a dropdown menu in the full [[mw:Special:MyLanguage/Help:Extension:CodeMirror#CodeMirror preferences|CodeMirror preferences]] dialog. For wikitext, available themes are default, colorblind-friendly (previously the colorblind preference option on [[Special:Preferences#mw-prefsection-editing]]) and no-highlighting. For code languages (i.e., CSS/JavaScript/JSON/Vue/Lua), there are several themes available. These same themes will eventually be available for wikitext, too. [https://phabricator.wikimedia.org/T163533] * From now on, wikis can restrict editing in the "User" namespace to only the page owner and certain user groups. [[mw:Special:MyLanguage/Manual:$wgRestrictUserPageEditing|Read the configuration documentation]] to learn more. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.14|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W31"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:49, 27 July 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30856308 --> == Tech News: 2026-32 == <section begin="technews-2026-W32"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/32|Translations]] are available. '''Updates for editors''' * The [[mw:Special:MyLanguage/Readers/Reader Experience|Reader Experience team]] has developed a [https://82db7c8d4b.catalyst.wmcloud.org/w/index.php?title=Regent%27s_Park&uselang=de patch demo] that wraps the page toolbar onto two lines when there is not enough horizontal space for all the buttons. This aims to reduce crowding in the Vector 2022 toolbar, which can occur on some language Wikipedias at certain screen widths. [https://phabricator.wikimedia.org/T429518] * The Reader Experience team is planning to launch [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]], a [[m:Special:MyLanguage/Community Wishlist Survey 2021/Mobile and apps/Have Apps reading lists available on Destop/Mobile|Community Wishlist item]], which is currently available to try in beta, as a full feature in September. Before then, volunteer translator help is needed for [https://translatewiki.net/w/i.php?title=Special%3ATranslate&group=ext-readinglists&filter=&action=translate string translations] into a number of languages. The feature supports reading and learning goals on Wikipedia. * Next week, the table of contents on Wikimedia Commons file pages will be improved by consolidating the file page table of contents with the page table of contents. This will make it easier to understand a file page’s structure, navigate to specific sections, and share links to individual sections. [https://phabricator.wikimedia.org/T332644] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:24}} community-submitted {{PLURAL:24|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where some [[w:TIFF|TIFF]] images failed to load after clicking their thumbnail, causing a broken image to be displayed instead of the full-size image, has now been fixed. [https://phabricator.wikimedia.org/T429326] '''Updates for technical contributors''' * The variable and function selector in AbuseFilter has been updated to support search and autocomplete. It will allow filter maintainers to find the desired variable or function more quickly. [https://phabricator.wikimedia.org/T323698] * The MJPEG and VP8 formats are removed from the video player. The MP4 format (MPEG-4 Part 2) is added instead, which provides higher quality videos to older iPhone devices. It may take a few weeks to retroactively update all existing videos. The default format for modern devices stays the same (VP9/WebM). [https://phabricator.wikimedia.org/T358266] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.15|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W32"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:46, 3 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30872536 --> == Tech News: 2026-33 == <section begin="technews-2026-W33"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/33|Translations]] are available. '''Updates for editors''' * [[File:Maki-gift-15.svg|12px|link=|class=skin-invert|Wishlist item]] A new ChartWizard is [[c:Special:ChartWizard/Data:Example.Pie.chart|now available on Wikimedia Commons]] for users interested in creating charts from their own data. The wizard makes the [[mw:Special:MyLanguage/Extension:Chart|Chart extension]] more beginner-friendly by allowing editors to create charts, such as bar and pie charts, without needing to use JSON. Users can still switch to the JSON editor if they prefer. Feedback on the new tool is welcome on the [[m:Talk:Community Wishlist/W414|wish talk page]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:19}} community-submitted {{PLURAL:19|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the Wikipedia iOS app’s Picture of the Day widget displayed the same image every day instead of updating daily, has now been fixed. [https://phabricator.wikimedia.org/T430692] '''Updates for technical contributors''' * [[mw:Special:MyLanguage/Extension:Math|Math formula]] SVG images will soon be generated in the browser instead of on the server. MathML continues to be generated on the server and renders in the browser without JavaScript. Wikibooks will see this change on 12 August, Wikisource on 19 August and Wikipedia from 20-27 August. You can try this by selecting "{{int:Mw-math-mathjax}}" in your preferences. This change is part of [[mw:Special:MyLanguage/RESTBase/deprecation|deprecating RESTBase]] and [[phab:T431372|deprecating Mathoid]]. [https://phabricator.wikimedia.org/T271001] * Category pages will soon support sorting entries by the time they are added to a category. This will make it easier to find recently or long-standing categorized pages. It will also improve workflows for maintenance categories such as deletion backlogs and other time-based review tasks. You can use <bdi lang="zxx" dir="ltr"><code><nowiki>cldsort=timestamp</nowiki></code></bdi> URL argument in category view to sort the entries. [https://phabricator.wikimedia.org/T433768] * [[mw:Special:MyLanguage/Extension:Gadgets|Gadgets]] and user scripts on Wikimedia wikis may now use [[phab:T395347|ES2018 features]] and [[phab:T419142|ES2019 features]] in JavaScript code. Previously, the platform only allowed up to ES2017. MediaWiki validates the source code to protect functionality from syntax errors and to ensure scripts are valid in all [[mw:Special:MyLanguage/Compatibility#Browser_support_matrix|supported browsers]]. [https://phabricator.wikimedia.org/T419142] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.16|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W33"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:45, 10 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30901051 --> == Tech News: 2026-34 == <section begin="technews-2026-W34"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/34|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Registration/Worklist|Worklist feature]] for the Event Registration tool is now live on all Wikimedia wikis. With Worklist, event organizers can add the articles their event will focus on directly to the event page. The Worklist also powers [[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Registration/Worklist#How Event Pathways uses the worklist|Event Pathways]] which notifies other editors of the upcoming or ongoing event when they edit an article featured in the event's Worklist. This is the minimum viable version (MVP), and feedback is welcome. Organizers are encouraged to try the feature. A hands-on [[m:Special:MyLanguage/Event:Worklist Setup Workshop: Get Your Event Ready|Worklist Setup Workshop]] will take place on 18 August at 16:00 UTC and 19 August at 11:00 UTC. '''Updates for editors''' * [[Special:ShortPages]] displays short pages by their size, but in many cases it gets filled with disambiguations and soft redirects, making it harder to find the short articles themselves. Starting this weekend, you will be able to choose not to include an article in the special page by adding the magic word <bdi lang="zxx" dir="ltr"><code><nowiki>__EXPECTSHORTPAGE__</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T433203] * One new wiki has been created: a {{int:project-localized-name-group-wikipedia/en}} in [[d:Q3436680|Bole]] ([[w:bol:|<bdi lang="zxx" dir="ltr"><code><nowiki>w:bol:</nowiki></code></bdi>]]) [https://phabricator.wikimedia.org/T429921] * Starting the week of August 17, the page toolbar will wrap onto two lines when there is not enough horizontal space for all the buttons. This is a [[phab:T429518|fully merged patch from the Reader Experience team]] which aims to reduce crowding in the Vector 2022 toolbar, that may occur on some language Wikipedias at certain screen widths. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:16}} community-submitted {{PLURAL:16|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, uploading large files to Wikimedia Commons has become more stable and less prone to failure following some fixes related to the “Could not acquire lock” upload error. [https://phabricator.wikimedia.org/T386640] '''Updates for technical contributors''' * Debian Bullseye will reach the end of its Long Term Support on 31 August 2026. [[phab:T434103|Some Cloud VPS projects]] still have instances running Debian Bullseye. Maintainers of those projects are encouraged to migrate to Debian Bookworm or Debian Trixie. A [[wikitech:Help:Cloud VPS instance operating system migration|migration guide]] is available to help with the process, and users may also want to consider whether their workload is better suited to Toolforge. If you need help or cannot complete the migration by 31 August, please contact the Cloud VPS admins as soon as possible. [[listarchive:list/cloud-announce@lists.wikimedia.org/thread/RVIPQSYLKMSL5M46JP6NEJVGVE6I2RXQ/|Read more]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.16|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W34"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:03, 17 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30922806 --> == Tech News: 2026-35 == <section begin="technews-2026-W35"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/35|Translations]] are available. '''Updates for editors''' * The [[Special:CreateAccount|Special:CreateAccount]] page has been simplified as part of ongoing work to modernize the account creation experience. The panel showing project statistics no longer appears next to the form on desktop and mobile web. Multiple account creation experiments show that a simpler form helps newcomers complete registration. [https://phabricator.wikimedia.org/T433783] * In order to improve page performance, images now load when they are viewed. This means images lower down an article will not load if a reader never scrolls to that part of the page, which may affect some image-related metrics. [https://phabricator.wikimedia.org/T148047] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:42}} community-submitted {{PLURAL:42|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where image thumbnails in Abstract Wikipedia could fail to display after the corresponding file was moved on Wikimedia Commons, has now been fixed. Thumbnails will now update correctly when files are moved. [https://phabricator.wikimedia.org/T433448] '''Updates for technical contributors''' * User Info card is a feature that helps patrollers see information about user accounts. So far, it has been available only in places such as page history, logs and recent changes. Now, it's possible to [[mw:Special:MyLanguage/Help:Extension:CheckUser#User_Info_card_in_page_content|place it in the page content]] as well, using the <bdi lang="zxx" dir="ltr"><code><nowiki>{{#uic:}}</nowiki></code></bdi> parser function. It can be particularly useful in templates like [[:en:Template:Userlinks|<bdi lang="zxx" dir="ltr"><code><nowiki>{{Userlinks}}</nowiki></code></bdi>]] (or their specialized variants), as it will make it easier to see the context about a user on various noticeboard pages. The card will be displayed only to users who have it enabled in their [[Special:Preferences#mw-input-wpcheckuser-userinfocard-enable|preferences]]. [https://phabricator.wikimedia.org/T424466] * Due to user security and privacy risks, we have disabled access to <bdi lang="zxx" dir="ltr"><code><nowiki>Special:MyPage</nowiki></code></bdi> URLs when specifically using <bdi lang="zxx" dir="ltr"><code><nowiki>action=raw</nowiki></code></bdi>. If you are impacted by this, consider whether you can use an alternative approach. <bdi lang="zxx" dir="ltr"><code><nowiki>Special:MyPage</nowiki></code></bdi> URLs can still be accessed and used without <bdi lang="zxx" dir="ltr"><code><nowiki>action=raw</nowiki></code></bdi>. Specified user page URLs (e.g. <bdi lang="zxx" dir="ltr"><code><nowiki>User:Myusername</nowiki></code></bdi>) can still be used with <bdi lang="zxx" dir="ltr"><code><nowiki>action=raw</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T120386] * Due to an update, the thumbnailing software has been improved. This includes upgrading <bdi lang="zxx" dir="ltr"><code><nowiki>librsvg</nowiki></code></bdi> to 2.60 and <bdi lang="zxx" dir="ltr"><code><nowiki>ImageMagick</nowiki></code></bdi> to 7, as well as resolving a number of long-standing thumbnailing bugs like rendering errors. [https://phabricator.wikimedia.org/T419815#12222841] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.17|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W35"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:45, 24 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30961208 --> == Tech News: 2026-36 == <section begin="technews-2026-W36"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/36|Translations]] are available. '''Weekly highlight''' * A new format for the Community Wishlist is open for feedback. You can [[m:Special:MyLanguage/Community Wishlist/Community Wishlist 2027|read the proposed ideas on Meta]]. This new process plans to improve how wishes are triaged, voted on, and prioritized in a way that is transparent and balanced across project families and language editions. This consultation is open for two weeks. '''Updates for editors''' * The latest release of the Wikipedia Android app includes updates to the Saved feature, bringing the app’s saving experience closer to iOS and Web. The update redesigns the Saved tab with an “All articles” view, removes the default “Saved” reading list, renames reading lists to “Collections,” and modernizes the article-saving experience. [https://phabricator.wikimedia.org/T420788] * The [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]] feature was enabled for all logged-in users on Bengali, Chinese, Czech and Vietnamese Wikipedias on August 25, after several months as a beta feature. Reading Lists will be available to all logged-in users on Arabic, French and Indonesian Wikipedias on September 1, followed by English Wikipedia on September 14, and all other Wikipedia wikis on September 28. * At the end of the month, some logged-out readers on Bengali, Czech, Persian, English, and Polish Wikipedias using the Minerva skin on mobile will see an [[mw:Special:MyLanguage/Readers/Reader_Growth/Minimal_Minerva|updated navigation bar]] in an [[w:A/B test|A/B test]]. The test will compare the current navigation bar with a new version designed to make it easier to find information more quickly. The goal is to determine whether these changes encourage readers to return more often. This experiment will not change the experience for logged-in readers and/or editors. * Editors who maintain redirects, templates, and categories used on redirect pages now have improved ways for finding and curating redirects. Previously, redirects pages could not be searched. Two new search keywords, <bdi lang="zxx" dir="ltr"><code><nowiki>onlyredirects:</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>withredirects:</nowiki></code></bdi>, now allow redirects to be searched directly and can be combined with existing keywords such as <bdi lang="zxx" dir="ltr"><code><nowiki>incategory:</nowiki></code></bdi>, <bdi lang="zxx" dir="ltr"><code><nowiki>intitle:</nowiki></code></bdi>, and <bdi lang="zxx" dir="ltr"><code><nowiki>insource:</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T204089] * The ISBN lookup tools for generating citations were recently not working because of external service problems. Developers are working on solutions. [https://phabricator.wikimedia.org/T435179] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where searching for pages by category using <bdi lang="zxx" dir="ltr"><code><nowiki>deepcat</nowiki></code></bdi> could return no results or unrelated results has now been fixed. [https://phabricator.wikimedia.org/T414859] '''Updates for technical contributors''' * The domain of URLs for thumbnails is changing from upload.wikimedia.org to thumb.wikimedia.org. The old URLs will continue to work for the foreseeable future but MediaWiki will advertise the new domain instead. URLs to other types of media such as original files, videos and transcodes will still be served from upload.wikimedia.org. [https://phabricator.wikimedia.org/T427465] * The Wikimedia [https://www.mediawiki.org/w/index.php?api=wmf-math%2Fv1&title=Special%3ARestSandbox Math API] is now deprecated. These endpoints will be fully sunset by the end of September 2026. Developers who call these endpoints should transition to alternative math rendering solutions, such as the native [https://developer.mozilla.org/en-US/docs/Web/MathML MathML] or [https://www.mathjax.org/ MathJax]. Third-party MediaWiki installations that utilize the Math extension for formula rendering are required to upgrade to v1.43+ to avoid disruption of service. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.18|MediaWiki]] '''In depth''' * Read more about [[mw:Special:MyLanguage/Edit_check/TextMatch|TextMatch]] in a Diff post titled, [[diffblog:2026/08/28/custom-edit-suggestions-for-every-wiki-how-communities-are-shaping-suggestion-mode-with-textmatch/|Custom edit suggestions for every wiki: How communities are shaping Suggestion Mode with TextMatch]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W36"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:53, 31 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30990659 --> == Tech News: 2026-37 == <section begin="technews-2026-W37"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/37|Translations]] are available. '''Updates for editors''' * [[mw:Special:MyLanguage/Help:Growth/Tools/Add_a_link|Add a Link]] has been upgraded for English Wikipedia users with improved detection of links that have different capitalization. This will help reduce ambiguous suggestions caused by differences in capitalization in article titles, including articles about cultural goods. A second phase of improvements is planned, which will also prepare the feature for release in other languages. [https://phabricator.wikimedia.org/T435526#12240876] [https://phabricator.wikimedia.org/T434259] * The [[mw:Special:MyLanguage/Article_guidance|Article guidance]] feature will be enabled by default for junior editors on Simple English and Turkish Wikipedia starting 10 September 2026 following [[mw:Special:MyLanguage/Article_guidance/Updates#Summary_of_experiment_result|an experiment]]. Junior editors with 0 to 99 edits will automatically see the feature when they click a red link or use the "[[tr:Vikipedi:Madde_sihirbazı|Madde oluşturto]]" option on Turkish Wikipedia to create a new article. The change is intended to help junior editors create higher-quality articles that meet each Wikipedia’s standards. [[phab:maniphest/query/z3tcTjmLMxk5/#R|Additional improvements]] will continue based on the experiment results and community feedback. * The [https://pageviews.wmcloud.org Pageviews Analysis] tool which allows users to compare pageviews across multiple pages, turns 10 years old this year and several new features have been added. They include [[toolforge:wikinav|WikiNav]] which provides insights into how readers of Wikipedia explore the content, editing stats in [https://pageviews.wmcloud.org/siteviews?range=latest-30&sites=en.wikipedia.org Siteviews], the ability to [https://pageviews.wmcloud.org/massviews?source=wikiproject&project=en.wikipedia.org lookup articles belonging to a WikiProject], and support for dark mode. [https://phabricator.wikimedia.org/T378549] * A [[mw:Special:MyLanguage/Readers/Reader_Growth/Minimal_Minerva|visually simplified Minerva]] navigation bar is being tested for logged-out readers using mobile web on the Bengali, Czech, English, Farsi, and Polish Wikipedias. The experiment aims to determine whether simplifying the navigation improves reader retention. The test will run from August 31 to September 28, and no action is required from users. * [[m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]] is working on improving [[en:Wikipedia:VisualEditor/Named references|auto-generated reference names in VisualEditor]]. Editors will only notice a slight change starting this week. When adding automatic reference names the numbering will start at <bdi lang="zxx" dir="ltr"><code><nowiki>:1</nowiki></code></bdi> instead of <bdi lang="zxx" dir="ltr"><code><nowiki>:0</nowiki></code></bdi>. Read more on the [[m:WMDE Technical Wishes/References/VisualEditor automatic reference names|project page]]. [https://gerrit.wikimedia.org/r/c/VisualEditor/VisualEditor/+/1332704] * All wikis will be [[m:Special:MyLanguage/Tech/Server switch|read-only for a few minutes]] on September 23. This is planned at 14:00 UTC. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T433363] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:25}} community-submitted {{PLURAL:25|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where [[mw:Special:MyLanguage/Parsoid|Parsoid]] could mishandle nested nowiki tags, causing content to be lost and displaying unwanted text has now been fixed. [https://phabricator.wikimedia.org/T435116] '''Updates for technical contributors''' * Interface administrators can configure gadgets from [[MediaWiki:Gadgets-definition]]. The definition format has been updated and no longer requires the <bdi lang="zxx" dir="ltr"><code><nowiki>ResourceLoader</nowiki></code></bdi> option, as gadgets are always loaded through <bdi lang="zxx" dir="ltr"><code><nowiki>ResourceLoader</nowiki></code></bdi>. This simplifies gadget configuration by removing an option that is no longer necessary, making gadget definitions easier for administrators. [https://phabricator.wikimedia.org/T298199] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.19|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W37"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:44, 7 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31008437 --> == Tech News: 2026-38 == <section begin="technews-2026-W38"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/38|Translations]] are available. '''Weekly highlight''' * The Future Audiences team has started a [[en:Special:MyLanguage/Wikipedia:Village pump (proposals)#New proposed experiment to let readers know about “Google preferred sources”|discussion on English Wikipedia]] about a proposed new experiment to show a temporary notice about the new [https://blog.google/products-and-platforms/products/search/original-high-quality-content-search/ Google Preferred Sources] feature to Wikipedia readers coming from Google. The experiment is to test whether this notice makes visitors come back to Wikipedia more often. Preferred Sources feature lets users choose websites they trust so Google can highlight content from those sources more prominently in Search and AI experiences. We are interested in testing this on other languages that Google supports and would welcome assistance with starting conversations on other wikis. If interested, please reach out to Future Audiences on the [[m:Special:MyLanguage/Future Audiences/Preferred sources|talk page]]. '''Updates for editors''' * The chat platform Discord is releasing a new self-service framework that websites can use to specify how their links should look when shared on Discord. The Future Audiences team is planning to start using this new framework to improve how Wikipedia links look when shared on Discord, giving better attribution and credit to contributors. The link appearance and behavior won't change in the first phase of this project as we want to first collect some baseline data to assess the impact of future changes. However, if community members who are active on Discord spot any issues, they can reach out on [[phab:tag/future-audiences/|Phabricator]] or [[m:Special:MyLanguage/Future Audiences|Metawiki]]. * The Reader Growth team will be running an experiment to test whether [[mw:Special:MyLanguage/Readers/Reader_Growth/Compact Lead|compacting article lead sections on mobiles]] with the addition of a "read more" button improves reader retention. The test will begin on September 17 on Arabic, Spanish, French, Indonesian, Italian, Japanese, Portuguese, Vietnamese, and Chinese Wikipedias and will run for four weeks. * All wikis will be [[m:Special:MyLanguage/Tech/Server switch|read-only for a few minutes]] on September 23. This is planned at 14:00 UTC. More information will be published in Tech News and will also be posted on individual wikis in the coming week. [https://phabricator.wikimedia.org/T433363] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where [https://wikistats.wmcloud.org/ Wikistats] for Wikipedias was returning an HTTP 500 error and could not be reached, has now been fixed. [https://phabricator.wikimedia.org/T435959] '''Updates for technical contributors''' * Developers who maintain a tool that queries the Wikimedia Commons links tables need to update their code to connect to the new x4 database cluster. The links tables have been moved from the s4 cluster to x4, and will no longer receive updates on s4. The page and redirect tables remain available on both clusters. A wiki replica for the x4 cluster will be set up afterwards. The change is being made because the s4 cluster has grown too large to operate efficiently. You can [[wikitech:Special:MyLanguage/News/2026 Commons links tables database split|read more]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.20|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W38"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 15:31, 14 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31039826 --> == Tech News: 2026-39 == <section begin="technews-2026-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/39|Translations]] are available. '''Weekly highlight''' * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on Wednesday, 23 September 2026 at [https://zonestamp.toolforge.org/1790172000 14:00 UTC]. This is for the datacenter server switchover backup tests, [[wikitech:Special:MyLanguage/Deployments/Yearly calendar|which happen twice a year]]. During the switchover, all Wikimedia website traffic is shifted from one primary data center to the backup data center to test availability and prevent service disruption even in emergencies. [https://phabricator.wikimedia.org/T433363] '''Updates for editors''' * The Growth team tested a new post-edit notice designed to [[mw:Special:MyLanguage/Contributors/Account Creation Experiments#4. Encourage Temporary Accounts to Register|encourage Temporary Account holders to register for a permanent account]]. The new notice replaced multiple dialogs and a simultaneous welcome notification with a single message highlighting the benefits of creating an account. The experiment increased permanent account creation from 1.94% to 3.66%, an 87% relative increase. The change will now be released to all wikis. [https://phabricator.wikimedia.org/T433551] * For Wikipedia editors using the [[Special:Preferences#mw-prefsection-betafeatures|"Suggestion mode" Beta Feature]], there is a [[Special:Preferences#mw-input-wpvisualeditor-editcheck-experimental|new opt-in user preference]] for showing "experimental" edit checks and suggestions. These types are listed at [[Special:EditChecks#experimental-checks|Special:EditChecks]], and are intended for early developer-testing and for gathering feedback from experienced users. Administrators can change the [[mw:Special:MyLanguage/Edit check/Configuration|configuration details]] for each suggestion as usual. Administrators can also [[mw:Special:MyLanguage/Help:Suggestion mode#Experimental Suggestions|use this feature]] to help test their community's ideas for locally created checks and suggestions. Experimental types will have a more distinct visual style later this week. [[mw:Talk:VisualEditor/Suggestion Mode|Feedback is welcome]]. * The [[m:CEE Technical Village Pump|CEE Technical Village Pump]] has been launched as a space for technical discussions and collaboration among Wikimedia communities in Central and Eastern Europe. * A new tool, [[mw:Special:MyLanguage/Language Onboarding and Development/Starter kit|Starter Kit]], is now available for new and small language Wikipedia communities. It brings together guided tasks, tools, and resources to help communities get started, monitor their progress, and collaborate with the broader Wikimedia community. Starter Kit is hosted on Wikimedia Toolforge and is designed for Wikipedias with fewer than 50,000 articles. Learn more about how Starter Kit works and how communities have been using it in [[diffblog:2026/09/18/introducing-starter-kit-for-new-and-small-language-wikipedias/|this Diff blog post]]. * The Reader Growth team is launching a retest of the [[mw:Special:MyLanguage/Readers/Reader Growth/Image Browsing|image carousel experiment]]. The retest will use three new versions of the design, updated based on community feedback. The team will assess results and determine with communities whether or not to proceed with the feature. The experiment will begin the week of September 28 and will run on Arabic, Bengali, Chinese, Czech, English, Farsi, French, German, Indonesian, Japanese, Polish, Portuguese, Spanish, Swedish, and Vietnamese Wikipedias. * After successful rollouts to Arabic, Bengali, Chinese, Czech, English, French, Indonesian, and Vietnamese Wikipedias, the [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists feature]] from the Reader Experience team will be available to all logged-in users on all Wikipedia wikis starting September 28. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the mentor status script repeatedly updated mentors’ status even when nothing had changed, creating unnecessary Recent Changes entries, has now been fixed. [https://phabricator.wikimedia.org/T436659] '''Updates for technical contributors''' * The <bdi lang="zxx" dir="ltr"><code><nowiki>abusefilters</nowiki></code></bdi> list query API, used to retrieve specific details about active or historical abuse filters configured on a wiki, has been updated to support the <bdi lang="zxx" dir="ltr"><code><nowiki>formatversion=2</nowiki></code></bdi> configuration parameter, thereby leading to breaking changes to the API response. All users who maintain user-scripts or other code need to check if they use the <bdi lang="zxx" dir="ltr"><code><nowiki>abusefilters</nowiki></code></bdi> list query API, and respond to any breaking changes. [https://phabricator.wikimedia.org/T435828] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.21|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W39"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 11:56, 27 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31085309 --> == Tech News: 2026-40 == <section begin="technews-2026-W40"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/40|Translations]] are available. '''Updates for editors''' * Users of default skins on desktop and mobile web (Vector 2022 and Minerva respectively) will now be informed if the search suggestions displayed as they type into Search come from page redirects. Previously, users could get confused when the top search suggestions did not match exactly what they had typed. The new redirect notice clarifies that these suggestions are not random, but related to the search. The suggested pages may be redirects to the most relevant destination articles being searched for. [https://phabricator.wikimedia.org/T303013] * Logged-out Wikipedia users on mobile web will begin to see a bookmark button for saving articles to their [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|reading lists]] instead of the current Watchstar button. When clicked, the bookmark button prompts users to log in or create an account to save an article for later. An earlier experiment found that the bookmark icon was four times more likely than the Watchstar button to encourage logged-out users to create an account. This change is part of efforts to encourage more readers to become account holders and use features that help them save and return to content. [https://phabricator.wikimedia.org/T438769] * An experiment will begin on September 29 on Spanish, Arabic, English, and French Wikipedias to simplify the experience users encounter immediately after account creation. The test will explore whether removing friction from the current Welcome Survey helps new users understand what to do next more easily. The experiment will run through the end of October. [https://phabricator.wikimedia.org/T430058] * The [[m:Special:MyLanguage/Product and Technology Advisory Council|Product and Technology Advisory Council]] has put out a call for the community to suggest topics that it should consider and discuss with the Wikimedia Foundation. Editors and technical contributors are invited to add topics to [[m:Talk:Product and Technology Advisory Council|the council's talk page]]. * Later this week, it will be possible for communities to configure [[mw:Special:MyLanguage/Help:Edit check|Edit Checks and Suggestions]] so that they are [[mw:Special:MyLanguage/Edit check/Configuration#extraNamespaces|shown within additional namespaces]], such as a <bdi lang="zxx" dir="ltr"><code><nowiki>Draft:</nowiki></code></bdi> namespace. [[mw:Talk:VisualEditor/Suggestion Mode|Feedback is welcome]]. * A bug in the [[m:Special:GlobalWatchlist|Global Watchlist]] is causing the page to fail to load for users that have unseen changes on Wikimedia Commons. Developers are working on a fix. Until then, affected users can follow the workarounds described in the [[mw:Special:MyLanguage/Extension:GlobalWatchlist#GlobalWatchlist temporarily broken for users with Wikimedia Commons|relevant]] help section. * New magic words <bdi lang="zxx" dir="ltr"><code><nowiki>{{CATEGORYSORT:TIMESTAMP}}</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>{{CATEGORYSORT:RTIMESTAMP}}</nowiki></code></bdi> are now available for use. They are able to change the default sorting of categories to be based on timestamp of categorization. [https://phabricator.wikimedia.org/T433768] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where [https://wikistats.wmcloud.org/ Wikistats] for Wikipedias was not reachable has now been fixed. [https://phabricator.wikimedia.org/T435959] '''Updates for technical contributors''' * The datacenter switchover, scheduled on September 23, has been postponed. [[diffblog:2025/03/12/hear-that-the-wikis-go-silent-twice-a-year/|The equinox exercise]] revealed capacity issues, preventing the switch of all services to the other datacenter. The process has been paused, prioritizing investigating that issue, to ensure that we continue to be able to serve our users reliably. A new exercise will be scheduled. Meanwhile, all traffic and edits continue to work as usual. * On September 23, a power loss briefly affected all wikis, creating intermittent issues on both reading and editing modes. This also affected Gerrit. This is unrelated to the datacenter switchover postponement. [https://www.wikimediastatus.net/incidents/9fm19t8qykk8] * [[mw:Special:MyLanguage/Help:Extension:Produnto|Produnto]] has been deployed to mediawiki.org and [[phab:T421436|some Indic language wikis]]. We want to hear your feedback on this experimental product. Produnto allows users to use Lua modules hosted in [[gitlab:repos/lua|Wikimedia's GitLab]]. It simplifies the sharing of Lua code between wikis. Instead of copying each individual Lua module from one wiki to another, users will be able to easily share packages across all wikis. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.22|MediaWiki]] '''Meetings and events''' * A [[m:Event:Cross-wiki Code Collaboration Workshop|Cross-wiki code collaboration workshop]] will be held online on October 2 at 12:30 UTC, bringing together South Asian technical contributors to learn about Produnto and begin piloting it on Hindi, Punjabi, Odia, Telugu, and Malayalam Wikipedias. Produnto is a package manager for deploying Lua modules hosted on GitLab to Wikimedia wikis, and was recently deployed on some pilot wikis. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W40"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 10:49, 28 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31092225 --> == Tech News: 2026-41 == <section begin="technews-2026-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/41|Translations]] are available. '''Weekly highlight''' * The process for this year’s Community Wishlist [[m:Special:MyLanguage/Community Wishlist/Community Wishlist 2027#Updated Community Wishlist Process 2027/2028|has been published]], incorporating community feedback. The wish submission process will [[m:Special:MyLanguage/Community Wishlist/FAQ#What is the deadline for submitting wishes?|end on November 8]]. This year, [[m:Special:MyLanguage/Community Wishlist/Community Wishlist 2027/Working group|a working group (open for volunteering)]] that includes community members familiar with the technical aspect of our wikis alongside Wikimedia Foundation staff, will take care of the [[m:Special:MyLanguage/Community Wishlist/FAQ#What is triage?|triage process]]. The triage is expected to be completed by late November. Votes for wishes will start in January. '''Updates for editors''' * Editors using the [[mw:Special:MyLanguage/VisualEditor|visual editor]] will now see a warning when they paste text that is likely to have initially been copied from one of five external generative AI chatbots into Wikipedia. This feature is known as [[mw:Special:MyLanguage/Edit check/LLM Paste Check|LLM Paste Check]]. It is a type of [[mw:Special:MyLanguage/Edit check|Edit Check]] that is community configurable. The check looks for markers in the copied HTML and is not using content watermark detection. Edits will also [[mw:Special:MyLanguage/Edit check/LLM Paste Check#Edit tags|be tagged]] so that patrollers can review them more closely. The feature helps newcomers add content that respects Wikipedia’s policies and makes it easier for experienced editors to identify problematic edits. Communities with local policies about LLM usage can [[mw:Special:MyLanguage/Edit check/LLM Paste Check#Configuration|adjust the wording and policy that is linked]]. The team [[listarchive:list/translators-l@lists.wikimedia.org/message/EVHKWJ4IERZELMPIWNH3XUVUSQV5KOO4/|apologizes]] that this was rolled out without a delay for translations. * Editors can now easily [[mw:Special:MyLanguage/Wikimedia Apps/Team/Future of Editing on the Mobile Apps|access the web visual editor directly from the iOS and Android apps]]. When opening the editor, users will be given a choice between visual editing and source editing. If they choose visual editing, they will be sent to a mobile web window in their phone's browser. After completing their edit, a banner will give them the option to return to the app. This enables readers to make quick contributions while casually reading. * Users of the Wikipedia Android and iOS apps will now see a one-time account creation prompt after they have used the app for two consecutive weeks. This prompt explains the benefits of having an account. It is intended to help more casual readers become logged-in users who return to the apps regularly. [https://phabricator.wikimedia.org/T434847] * Editors on [[wmnoc:conf/dblists/group1.dblist|group1 wikis]], including Wikiquote, Wikibooks, Wikiversity, Wikivoyage, and Wikisource, will no longer see notifications on [[mw:Special:MyLanguage/Help:Recent changes|Recent Changes]] and [[mw:Special:MyLanguage/Help: Watching pages|Watchlist]] when a link to another language version of a page is added, removed, or changed in its Wikidata item. This change will begin on October 5 at 07:00 UTC as a two-week trial to reduce high-volume, low-value notifications and make important changes easier to identify. Editors who rely on these notifications can read more on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project page]] and share feedback or concerns on the [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]]. [https://phabricator.wikimedia.org/T439415] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:36}} community-submitted {{PLURAL:36|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where mentors who removed themselves from the mentorship program could still have mentees assigned to them and receive questions, has now been fixed. Mentees will now be reassigned when a mentor leaves the program. [https://phabricator.wikimedia.org/T418194] '''Updates for technical contributors''' * Wikimedia Brasil has published its [[m:Special:MyLanguage/Wikimedia Brasil/Arcabouço de Boas Práticas de Desenvolvimento|Development Best Practices Framework]] (ABPD). It is a guide for staff, contractors and volunteers building technical tools and projects. It covers the project lifecycle, security, accessibility, personal data protection and responsible AI use, and explains how movement-wide guidelines were adapted to a local context. They encourage other affiliates to reuse it and adapt it. Read more in the [[wmfblog:2026/09/26/wikimedia-brasils-development-best-practices-framework-technical-sustainability-as-an-organizational-responsibility|Diff post]]. * A new, canonical base URL for Wikimedia APIs will soon be introduced. The new canonical route follows a <bdi lang="zxx" dir="ltr"><code><nowiki>{projectName}/api/</nowiki></code></bdi> pattern and will act as an alternative path for current REST APIs (for example: <bdi lang="zxx" dir="ltr"><code><nowiki>{projectName}/w/rest.php/</nowiki></code></bdi>). Both versions will be callable for all existing APIs, but the new structure will be the preferred path for newly created API modules. This change will be non-breaking for most users. The existing pathways will remain available for all existing endpoint requests. However, some endpoints may return URLs following the new pattern in response bodies. Changes will be available on test wiki first, with the rollout expected to cover all wikis by the end of October. [https://phabricator.wikimedia.org/T433535] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.23|MediaWiki]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W41"/> 18:52, 5 October 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31098825 --> == Tech News: 2026-42 == <section begin="technews-2026-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/42|Translations]] are available. '''Weekly highlight''' * Starting October 13, wikis can change the default pattern for [[:en:Wikipedia:VisualEditor/Named references|auto-generated reference names in VisualEditor]] (currently <syntaxhighlight lang="wikitext" inline><ref name=":1" /></syntaxhighlight>). They will be able to use human-readable, content-based reference names that are more helpful to contributors using the source editor (e.g. <syntaxhighlight lang="wikitext" inline><ref name="Miller2026-1" /></syntaxhighlight>). VisualEditor reference name patterns can be defined using MediaWiki system messages, JSON, templates and modules ([[:mw:Special:MyLanguage/Help:Cite/VisualEditor reference names|more information]]). Admins can enable these changes via [[Special:CommunityConfiguration/Cite-VisualEditor-Autonames|community configuration]]. This is a [[:m:Special:MyLanguage/Community_Wishlist/W17|community wish]] implemented by [[:m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]]. [https://phabricator.wikimedia.org/T436255] * [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|Sub-referencing]] is a new MediaWiki feature that allows editors to reuse references with different details. It will be deployed to English Wikipedia on October 14 and to remaining Wikimedia Foundation wikis by end of October (likely October 21). The [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#deployment|FAQ]] lists possible actions to take on your wiki to support the deployment. This is a [[:m:WMDE Technical Wishes/Sub-referencing/History|long-standing community wish]] implemented by [[:m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]]. [https://phabricator.wikimedia.org/T440243][https://phabricator.wikimedia.org/T440304] '''Updates for editors''' * [[mw:Special:MyLanguage/Moderator Tools|Moderator Tools]] will be removing the list view of the Watchlist and defaulting everyone to the changelog view. Previously, there were two versions of how the Watchlist is shown to mobile web users: the list view, where editors could see watched articles in a list format, and the changelog view, where editors could see changes to watched articles in a log format, controlled by a user's Advanced Mobile Control settings. This has created issues for code-base maintenance: two different displays means two sets of code to manage. By defaulting to the changelog view, we are simplifying the codebase and avoiding the likelihood of missing bugs. * The Wikipedia Android app is testing a way to listen to article introductions in the “For you” feed. A text-to-speech model reads the existing article text aloud without rewriting it or adding any content. The 30-day experiment will begin in the Wikipedia Beta app during the third week of September, then move to the regular Wikipedia Android app in October for a limited group of eligible users. A small portion of app users (those with English feeds and at least one topic interest) will have access to the feature. This experiment is part of broader efforts to give app readers options in how they consume content in order to deepen engagement and user retention. [[mw:Special:MyLanguage/Readers/Listening to Wikipedia/Phase 1|Learn more]] and [[mw:Talk:Readers/Listening to Wikipedia|share feedback]]. * [[mw:Special:MyLanguage/Help:Extension:CodeMirror|CodeMirror syntax highlighting]] was [[phab:T288161|enabled]] by default for all logged out and newly registered users on the English Wikipedia on September 14. With no signs of adverse effects, the same change is being proposed to be made globally across all wikis in a few weeks. If you have concerns or feedback, or if your wiki would like to opt out, [[mw:Special:MyLanguage/Help talk:Extension:CodeMirror#Enabling CodeMirror by default on all WMF wikis for newbies|please see the help page]]. [https://phabricator.wikimedia.org/T440077] * [[d:Wikidata:Usability_and_usefulness/Item_editing_experience/Mobile_editing_of_statements|Wikidata mobile statement editing]] of all datatypes will be officially launched on October 13, when it will be removed from Wikidata [[d:Special:Preferences#mw-prefsection-betafeatures|beta features]] and become available to all editors. Users can [[d:Wikidata_talk:Usability_and_usefulness/Item_editing_experience/Mobile_editing_of_statements|report bugs and share feedback]]. * Last week, language link changes were removed from [[Special:RecentChanges|Recent Changes]] and [[Special:Watchlist|Watchlist]] feeds on Wikivoyage, Wikisource, Wikiversity, Wikiquote and Wiktionary. As no adverse effects have been observed, the [[m:Wikidata_For_Wikimedia_Projects|Wikidata For Wikimedia Projects]] plans to roll out this change globally to all Wikipedias. This is scheduled for October 13 at 07:00 UTC, after which editors will no longer see when a link to ''another'' language version of a page is added, removed, or changed in its Wikidata item. Editors who rely on these notifications can read more on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project page]] and share feedback or ask to opt out their wiki on the [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]]. [https://phabricator.wikimedia.org/T440698] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where accidentally touching the graph while scrolling on the Pageviews tool on mobile could unintentionally zoom in has now been fixed. Click-and-drag zoom is now disabled on touch devices. [https://phabricator.wikimedia.org/T440075] '''Updates for technical contributors''' * There are three major changes coming to dumps: the legacy content dumps [https://lists.wikimedia.org/hyperkitty/list/xmldatadumps-l@lists.wikimedia.org/thread/E6D5EU4PMSTSOI2J7A46HJ3YW2W554CS/ deprecated in January 2026] will now be sunset, the replacement [https://wikitech.wikimedia.org/wiki/MediaWiki_Content_File_Exports MediaWiki Content File Exports] will be delayed to implement a “safety buffer”, and they are now also available as 7zip-compressed files. Users will need to switch the URL they download their dump from. For more information, timeline and migration instructions, see [https://wikitech.wikimedia.org/wiki/Legacy_content_dumps_sunset Legacy content dumps sunset]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.24|MediaWiki]] '''In depth''' * The Wikimedia Foundation discovered unauthorized activity by OpenAI agents on Wikimedia projects, including edits to wikis, attempts to exploit a public note-taking tool, and heavy automated traffic. [[diffblog:2026/10/05/openai-rogue-agent-activities-found-on-wikimedia-projects/|Read the blog post on Diff]] for more details about the activity and the Foundation’s response. '''Meetings and events''' * Save the date for the next Wikimedia Hackathon! We’ll be meeting in lovely Tirana, Albania for the [https://www.mediawiki.org/wiki/Wikimedia%20Hackathon%202027 2027 Wikimedia Hackathon] from April 9–11, 2027. Scholarship and staff sponsorship applications are currently being [https://pretix.eu/wikimedia/Hackathon-2027/ accepted through Pretix] and will close on October 30, 2026. General registration will open in January 2027. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W42"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 07:40, 13 October 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31142468 --> == Tech News: 2026-43 == <section begin="technews-2026-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/43|Translations]] are available. '''Updates for editors''' * To measure the impact of incorporating some [[mw:Special:MyLanguage/Readers/Reader_Growth/Image_Browsing#November 2025: Ideas and feedback|community-requested features]] on logged-out reader retention, a test for [[mw:Special:MyLanguage/Readers/Reader_Growth/Image_Browsing|Image Carousel]] will be pushed to logged-out readers. With the Image Carousel feature, readers browse community-uploaded images, selected by editors as relevant to specific articles. The test starts on November 20. * An experimental notice will be pushed to 0.5% of logged-out mobile readers who come to English Wikipedia from Google, asking them to add Wikipedia as a [https://blog.google/products-and-platforms/products/search/preferred-sources/ Google Preferred Source]. The test is to see if this notice increases reader retention and encourages people who use Google Search to visit Wikipedia more often. It will run from October 15–29 and will be assessed for its impact on retention and referrals. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:26}} community-submitted {{PLURAL:26|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where [[quarry:|Quarry]] returned an “Access denied” error when users tried to run SQL queries, preventing queries from running normally, has now been fixed. [https://phabricator.wikimedia.org/T440966] '''Updates for technical contributors''' * [[File:Cog-icon-grey.svg|12px|link=|class=skin-invert|Advanced item]] Due to a long-standing bug, applications that use the [[mw:Special:MyLanguage/OAuth/For_Developers|OAuth 2]] client credentials flow to act on their owners’ behalf are treated as if they are logged out. This will be fixed for new applications registered on or after Monday, October 19. Some affected applications need to re-register. [https://phabricator.wikimedia.org/T420297] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.1|MediaWiki]] '''Meetings and events''' * A proposal to hold the Wikimedia Hackathon every three years, with regional hackathons in between, [[mw:Wikimedia Hackathon/Community Proposal 2026|has been shared]]. It explores making the event more accessible to technical communities in different regions. Share your feedback on the proposal’s [[mw:Talk:Wikimedia Hackathon/Community Proposal 2026|talk page]] before November 6. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W43"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:38, 19 October 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31178499 --> == Tech News: 2026-44 == <section begin="technews-2026-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/44|Translations]] are available. '''Weekly highlight''' * An experiment launched on September 29 is testing [[mw:Special:MyLanguage/Readers/Reader_Experience/Reading_recommendations|article recommendations]] for new account holders who also identify as readers. By suggesting articles to read, similar to recommendations in the Wikipedia app for logged-in readers, the experiment aims to encourage new account holders to read and return to the website regularly, with the goal of increasing internal referrals by 1%. See the related [[m:Community Wishlist/W505|Community Wishlist]] proposal. * Several Wikimedia services were taken offline last week because of a [https://www.php.net/archive/2026.php#2026-10-20-1 security vulnerability in PHP]. This is because they need to be updated before they are safe to put back online. This is not a problem just for the Wikimedia movement but affects a lot of websites. You can follow updates on [[wikitech:Incidents/2026-10-21 PHP security update/Community|Wikitech]]. Cloud VPS and Toolforge will take longer to bring back online. This is to make sure that applications which run on Cloud VPS or Toolforge are not affected. Tool developers can see updates and more information on the [https://lists.wikimedia.org/postorius/lists/cloud-announce.lists.wikimedia.org/ Cloud-announce mailing list]. [https://diff.wikimedia.org/2026/10/21/impact-of-php-vulnerabilities-on-wikimedia-tools-and-services/][https://diff.wikimedia.org/2026/10/21/impact-of-php-vulnerabilities-on-wikimedia-cloud-services/] * [[m:Special:MyLanguage/Tech/News/2026/43|Last week we shared]] that to measure the impact of incorporating some community-requested features on logged-out reader retention, a test for the [[mw:Special:MyLanguage/Readers/Reader Growth/Image Browsing|Image Carousel]] feature would be pushed to logged-out readers. Due to an issue, we will be restarting the test, but it will be live on October 26, not November 20 as initially announced. '''Updates for editors''' * A new [[wikitech:KAPOW|bot detection system]] to better identify automated traffic that disguises itself as human visitors, is coming to the Wikimedia wikis. This might cause sudden changes to visitor statistics starting from 26 October, going back to 20 June 2026. * The [[mw:Special:MyLanguage/Extension:Score|Score extension]] which renders musical notation inside wiki pages, has been temporarily disabled on all wikis due to a security issue. Affected pages will display a notice instead of musical scores, but the underlying code remains intact. No action is needed from editors, and a fix is in progress. A separate announcement will follow when the extension is re-enabled. Read more on [[phab:T441579|Phabricator]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:18}} community-submitted {{PLURAL:18|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where CodeMirror syntax highlighter appears to have been enabled in error for existing editors has been fixed. [https://phabricator.wikimedia.org/T441308] '''Updates for technical contributors''' * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on Wednesday, October 28 2026 at [https://zonestamp.toolforge.org/1793199600 15:00 UTC]. This is for the datacenter server switchover backup tests, [[wikitech:Deployments/Yearly calendar|which happen twice a year]]. During the switchover, all Wikimedia website traffic is shifted from one primary data center to the backup data center to test availability and prevent service disruption even in emergencies. [https://phabricator.wikimedia.org/T439703] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.2|MediaWiki]] '''Meetings and events''' * Scholarship and sponsorship applications for the [https://www.mediawiki.org/wiki/Wikimedia%20Hackathon%202027 2027 Wikimedia Hackathon] will close on Friday, October 30th. Submit your application [https://pretix.eu/wikimedia/Hackathon-2027/ through Pretix] before the deadline! '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W44"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:56, 26 October 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31199592 --> == Tech News: 2026-45 == <section begin="technews-2026-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/45|Translations]] are available. '''Weekly highlight''' * Many Wikimedia tools were taken offline last week because of a [[:w:PHP2Shell|security vulnerability in PHP]]. This affected many websites worldwide. [[m:Special:MyLanguage/Toolforge|Toolforge]] and [[m:Special:MyLanguage/Wikimedia Cloud Services|Cloud VPS]] have been back up since October 22. Many important tools have been gradually restored. Some tools need the respective volunteer maintainers to restart them. Others still need to upgrade to a patched PHP version. Some tools were using older versions of PHP which are not supported by the recent security patches. They will require maintainers to upgrade to a more recent version. This might require additional effort. You can follow the work [[:wikitech:Talk:Incidents/2026-10-21 PHP security update/Community#Exceptions|on Wikitech]]. '''Updates for editors''' * A new optional search experiment is running in the Wikipedia Android and iOS apps for Arabic, French, and Japanese Wikipedias. Participating readers can search inside articles and open quoted passages directly in their source articles, no answers or summaries are generated. This is the first of four experiments in [[mw:Special:MyLanguage/Readers/Information%20Retrieval/Phase%202|Phase 2 of Semantic Search]]. It began on October 22 and runs for 20 days. Feedback is welcome on the project’s [[mw:Special:MyLanguage/Talk:Readers/Information%20Retrieval/Phase%202|discussion page]]. * The [[m:Special:MyLanguage/Future_Audiences|Future Audiences]] team is planning to bring [[m:Special:MyLanguage/Future_Audiences/Share_card|Share Cards]] to Wikipedia on mobile. This feature gives users the option to share a visually appealing card with friends, based on the article they are reading. The card contains the article’s title, image, opening text, and related attribution, and links back to the article for full reading. Editors are invited to try out this feature by adding <code dir="ltr">?useformat=mobile&sharecard=1</code> to any article URL from October 29 to November 8. Share any thoughts on the [[m:Talk:Future_Audiences/Share_card| project talk page]] and report any bugs on [[phab:T439161|Phabricator]]. * The default renderer for math formulas will change on November 2. After the change, the server sends the formula as MathML, and your browser uses MathJax to show it. This is the last step towards the Mathoid/RESTBase deprecation process, for sustainability and security reasons. You can [[w:en:Wikipedia:WikiProject Mathematics/MathFormattingBugs|ask questions or report problems]]. [https://phabricator.wikimedia.org/T375238] * Do you have an idea for a new feature, or a bug that needs fixing? [[m:Special:MyLanguage/Community Wishlist|Submit your suggestion for the community wish list by November 8!]] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:41}} community-submitted {{PLURAL:41|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.3|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W45"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:23, 3 November 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31236748 --> == Tech News: 2026-46 == <section begin="technews-2026-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/46|Translations]] are available. '''Weekly highlight''' * The Wikipedia Apps team is preparing to launch Year in Review in early December. Year in Review gives app users a personalized recap of how they read and engaged with Wikipedia throughout the year. The team is looking for volunteers to help make it available in as many languages as possible. Translators can contribute through [https://translatewiki.net/ translatewiki.net]. For [https://translatewiki.net/w/i.php?title=Special:Translate&action=translate&group=out-wikimedia-mobile-wikipedia-android-strings&filter=%21translated Android], search for <bdi lang="zxx" dir="ltr"><code><nowiki>yir</nowiki></code></bdi> under the "Untranslated" tab, and for [https://translatewiki.net/w/i.php?title=Special:Translate&action=translate&group=out-wikimedia-mobile-wikipedia-ios&filter=%21translated&optional=1 iOS], search for <bdi lang="zxx" dir="ltr"><code><nowiki>year-in-review</nowiki></code></bdi> under the "Untranslated" tab. * The [[mw:Special:MyLanguage/Article guidance|Article guidance]] feature that helps editors create articles that follow a Wikipedia’s policies, is now available on all Wikipedias. Administrators and interface admins can configure and expose it for editors to use via [[Special:CommunityConfiguration/ArticleGuidance]]. A [[mw:Special:MyLanguage/Article guidance/Community Configuration|configuration guide is available]]. Visit [[mw:Talk:Article guidance|the project talk page]] to ask any questions. '''Updates for editors''' * Following the release of [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]] to all Wikipedias in September, logged-in users will soon be able to [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists#October/November 2026: Custom collections and call to action|organize articles saved in their lists into customizable categories]]. This will enable readers to create collections and revisit saved articles based on their interests, potentially encouraging frequent visits to Wikipedia. The update will roll out to all Wikipedia users between November 9 and 16. * The Wikipedia Apps team is preparing to launch the first of two notification experiments for English Wikipedia readers on Android who have opted in to notifications. The three-week experiment will send notifications suggesting personalized Discover reading lists which are collections of Wikipedia articles recommended based on articles the reader has previously viewed. The goal is to understand whether these recommendations help readers discover relevant content and encourage them to return to the app. No action is required, and users can manage their notification preferences in the app settings. [[mw:Wikimedia Apps/Team/Notifications|Learn more and share feedback]]. * A bug in the [[m:Special:GlobalWatchlist|Global Watchlist]] was causing the page to fail to load for users who have unseen changes on Wikimedia Commons. The bug has now been fixed. If you temporarily removed <bdi lang="zxx" dir="ltr"><code><nowiki>commons.wikimedia.org</nowiki></code></bdi> from your personal [[m:Special:GlobalWatchlistSettings|Global Watchlist settings]] due to the bug, you can restore it there. [https://phabricator.wikimedia.org/T439203] * A new Beta feature called "Home" will be [[mw:Special:MyLanguage/Home/Deployment|deployed to 10 Wikipedias]] for a limited test. This new feature aims to replace <bdi lang="zxx" dir="ltr"><code><nowiki>Special:Homepage</nowiki></code></bdi> for newcomers, with additional modules planned for the future to improve upon the current experience. If you want to participate in the test, please [[mw:Talk:Home|sign up]]. "Home" will be released to all users later this month. * On English and Russian Wikipedias, [[m:User:Alaexis/Source Verifier|Source Verification]] is now available as an experimental Suggestion for experienced editors within [[mw:Special:MyLanguage/VisualEditor/Suggestion_Mode|Suggestion Mode]]. It uses an LLM hosted on [[wikitech:Machine_Learning/LiftWing|LiftWing]] to try to check whether a cited source supports the claim it’s attached to. To try it out, please [[phab:T426359|see these testing instructions]]. If you are at another language Wikipedia and your community is interested in trying it out, please [[m:User talk:Alaexis/Source Verifier|express your interest]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:35}} community-submitted {{PLURAL:35|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where dates passed as blank parameters to functions in wikitext were incorrectly interpreted using the month-day-year format instead of the day-month-year format, has now been fixed. [https://phabricator.wikimedia.org/T403884] '''Updates for technical contributors''' * Starting on 1 December 2026, hCaptcha will be required for edits made via the API by non-autoconfirmed users. If your tool, gadget, or user script makes edits on behalf of newcomer users, [[mw:Special:MyLanguage/Product Safety and Integrity/hCaptcha#November 2026: Completing hCaptcha rollout|see how to update it]]. * [[wikitech:Help talk:Toolforge/Toolforge standards committee#November 2026 committee nominations|Nominations are open on Wikitech]] for new [[wikitech:Help:Toolforge/Toolforge standards committee|Toolforge standards committee]] members. The committee oversees the Toolforge [[wikitech:Help:Toolforge/Right to fork policy|Right to fork policy]] and [[wikitech:Help:Toolforge/Abandoned tool policy|Abandoned tool policy]] among other duties. Nominations close on 22 November 2026. * Toolforge has introduced two new beta features. "Toolforge alerts" send email notifications when a tool becomes unavailable, returns errors, or restarts frequently. "Extended logging" makes it easier to investigate problems by providing logs for events such as job creation, deletion, and deployment failures through the <bdi lang="zxx" dir="ltr"><code><nowiki>toolforge logs</nowiki></code></bdi> command. Both features are opt-in and help tool maintainers become aware of and resolve problems with their tools more quickly. Maintainers can [[wikitech:Help:Toolforge/Alerts|enable alerts]] and learn how to [[wikitech:Help:Toolforge/Running_jobs#Toolforge_logs|access extended logs]]. They are also encouraged to try the features and [[wikitech:Help:Cloud_Services_communication|provide feedback]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.4|MediaWiki]] '''Meetings and events''' * A proposal to change how we currently organize the Wikimedia Hackathon [[mw:Special:MyLanguage/Wikimedia Hackathon/Community Proposal 2026|has been shared]]. It explores making the event more accessible to technical communities in different regions. Share your feedback on the proposal’s [[mw:Special:MyLanguage/Talk:Wikimedia Hackathon/Community Proposal 2026|talk page]]; the deadline has been extended to November 13th. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W46"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 10:34, 9 November 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31249348 --> 3hv2imm47fjypmka5a4gshtlaxadvbn 0 168889 2844955 2777413 2026-11-09T08:56:56Z ATechPerson 3002376 ce 2844955 wikitext text/x-wiki The '''[[w:Cri_du_Chat|Cri du Chat]]''' is a rare genetic disease in which caused by a missing piece of [[w:Chromosome 5|Chromosome 5]] (5p MonoSomy). The name came from the infant's crying, which is like a cat, and also high pitched ("Cri du Chat" is a French term, meaning "Cat Cry"). The disease was first discovered by [[w:Jérôme Lejeune|Jérôme Lejeune]] in 1963, in which is why it's also named ''Lejeune's Disease''. The cure for this disease is unknown. == Cure == * To help with communication skills, teach sign language for the child. * Speech Theropy, which can improve the poor language ability. * Physical Theropy, which can improve the poor muscle. === Get Help === * Your legal Doctor * Cri du Chat Support of Australia. (03) 9775 9962 * Association for Children with Disability. 03) 9818 2000 or 1800 654 013 * Better Start for Children with Disabilities. 1800 242 636 == Symptoms == * Drooling a lot * Unusual facial features, such as buck teeth. * Behavior, such as agression. * Big/Slanted Eyes * Rigid teeth * Flatten Nose and Small head. == Facts == *The disease becomes less noticeable as you grow up. *Girls get this disease more than boys == Sources == * http://www.nytimes.com/health/guides/disease/cri-du-chat-syndrome/overview.html * http://www.genome.gov/19517558 * http://emedicine.medscape.com/article/942897-treatment * http://rarediseases.info.nih.gov/gard/6213/cri-du-chat-syndrome/resources/1 * http://ghr.nlm.nih.gov/condition/cri-du-chat-syndrome/show/MedlinePlus * http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Cri_du_chat_syndrome * https://sites.google.com/site/criduchat304/extra-facts * http://www.newhealthguide.org/Life-Expectancy-Of-Cri-Du-Chat-Syndrome.html [[Category:Diseases]] [[Category:Genetics]] 5dzwdd7jzl0fx484kjhfbpzugn4ft5w 0 171301 2844889 2844150 2026-11-08T17:57:15Z James500 297601 /* Biographical dictionaries etc */ Add 2844889 wikitext text/x-wiki {{Center top}}{{Resize|3em|'''Bibliotheca Universalis'''}}{{Center bottom}} {{Bibliography}} {{research}} If this resource is ever completed, it will be a universal bibliography.<ref>See [[w:Bibliography]].</ref> Until then, it will be an approximation of a universal bibliography. This bibliography is arranged as an index of topics. ==Index== *[[Universal Bibliography/Bibliography|Bibliography]] *[[Universal Bibliography/Libraries|Libraries]] *[[Universal Bibliography/Literature|Literature]] *[[Universal Bibliography/Languages|Languages]] *[[Universal Bibliography/SF|SF]] *[[Universal Bibliography/Music|Music]] *[[Universal Bibliography/Cinema|Cinema]] *[[Universal Bibliography/Television|Television]] *[[Universal Bibliography/Culture|Culture]] *[[Universal Bibliography/Publishers and imprints|Publishers and imprints]] *[[Universal Bibliography/Printing|Printing]] *[[Universal Bibliography/Printers|Printers]] *[[Universal Bibliography/Microform|Microform]] *[[Universal Bibliography/Periodicals|Periodicals]] *[[Universal Bibliography/Reference|Reference]] *[[Universal Bibliography/Gazetteers|Gazetteers]] *[[Universal Bibliography/Humanities|Humanities]] *[[Universal Bibliography/Law|Law]] *[[Universal Bibliography/History|History]] *[[Universal Bibliography/Archaeology|Archaeology]] *[[Universal Bibliography/Geography|Geography]] *[[Universal Bibliography/Continents|Continents]] *[[Universal Bibliography/Countries|Countries]] *[[Universal Bibliography/Architecture|Architecture]] *[[Universal Bibliography/Mathematics|Mathematics]] *[[Universal Bibliography/Computers|Computers]] *[[Universal Bibliography/Kites|Kites]] *[[Universal Bibliography/Nostalgia|Nostalgia]] *[[Universal Bibliography/Children's non-fiction|Children's non-fiction]] ===About=== *[[Universal Bibliography/About|About]] ==Online libraries== Swedish: *[[w:Swedish Literature Bank|Litteraturbanken]] (Swedish Literature Bank) *[[w:Project Runeberg|Projekt Runeberg]] (Project Runeberg) French *[[w:Persée (web portal)|Persée]] (persee.fr) Japanese *[[w:Aozora Bunko|Aozora Bunko]] (aozora.gr.jp) ==Biographical dictionaries etc== See [[w:Bibliography of encyclopedias: general biographies]] and [[w:List of biographical dictionaries]] *Fox. 'True Biographies of Nations?': The Cultural Journeys of Dictionaries of National Biography. ANU Press. 2019 [https://books.google.co.uk/books?id=siSbDwAAQBAJ&pg=PP1#v=onepage&q&f=false] *Arthur, "Biographical Dictionaries in the Digital Era". Advancing Digital Humanities: Research, Methods, Theories. 2014. Chapter 6. [https://books.google.co.uk/books?id=z7MaBgAAQBAJ&pg=PA83#v=onepage&q&f=false Page 83] et seq. Bibliographies, indexes, etc: *Wynar. ARBA Guide to Biographical Dictionaries. Libraries Unlimited. 1986 [https://books.google.co.uk/books?id=5FfgAAAAMAAJ] *Slocum, Robert B (ed). Biographical Dictionaries and Related Works. Gale Research Company. 2nd Ed: 1986 [https://books.google.co.uk/books?id=5uMpAQAAMAAJ] *Biographical Dictionaries Master Index. (Gale Biographical Index Series). [https://books.google.co.uk/books?id=ZEshAQAAMAAJ] [https://books.google.co.uk/books?id=pPAzAQAAIAAJ] see also [https://books.google.co.uk/books?id=o_gPAQAAMAAJ] *Children's Authors and Illustrators: An Index to Biographical Dictionaries. (Gale Biographical Index Series). 2nd Ed: 1978,  3rd Ed: 1981, 4th Ed: 1987 [https://books.google.co.uk/books?id=VIsWAQAAMAAJ] [https://books.google.co.uk/books?id=DFtGAQAAIAAJ] [https://books.google.co.uk/books?id=01wjAQAAIAAJ] *Index to the Wilson Authors Series [https://books.google.co.uk/books?id=oNZkAAAAMAAJ] *Auchterlonie. Arabic Biographical Dictionaries: A Summary Guide and Bibliography. 1987 [https://books.google.co.uk/books?id=rW59QgAACAAJ] *Black Biographical Dictionaries, 1790-1950 [https://books.google.co.uk/books?id=laIUAQAAMAAJ] Particular works: *Oxford Dictionary of National Biography; [[w:Dictionary of National Biography|Dictionary of National Biography]] *Boase. Modern English Biography. ([http://www.google.com/search?q=editions%3Auzt3-qMuFcMC&btnG=Search+Books&bksoutput=html_text&tbm=bks&tbo=1 editions:uzt3-qMuFcMC]) *A & C Black's Who's Who *Who Was Who *The Academic Who's Who. A & C Black. 1st Ed: 1973 [https://books.google.co.uk/books?id=dnUWAQAAMAAJ] [https://books.google.co.uk/books?id=fXJmAAAAMAAJ]. 2nd Ed: 1975. Commentary: [https://books.google.co.uk/books?id=7VyOANl2qxoC&pg=PA208&output=html_text]. GBooks: editions:INAP7GGD2gYC editions:tA0FkHC75FIC *Dictionary of Edwardian Biography (Pike's New Century Series) Works that comprise largely of biographies: *The Penguin Companion to Literature Theatres *A Biographical Dictionary of Actors, Actresses, Musicians, Dancers, Managers & Other Stage Personnel in London, 1660-1800. [https://books.google.co.uk/books?id=TGgS9VxWJ0oC vol 15] Music *William York. Who's Who in Rock Music. Charles Scribner's Sons. New York. 1982. [https://books.google.co.uk/books?redir_esc=y&id=3ggKAQAAMAAJ] ==Dictionaries of dates== [https://archive.org/search.php?query=%22dictionary%20of%20dates%22 Archive.org] *Baxter Dictionary of Dates and Events. 1st Ed: 1963: Napier, M (ed). 2nd Ed: 1971: Sanders and Laffin. Commentary: 92 Library Journal 1819 [https://books.google.co.uk/books?id=CExVAAAAYAAJ] *Beeching, Cyril Leslie. A Dictionary of Dates. OUP. 1st Ed: 1993. 2nd Ed: 1997. [https://www.google.co.uk/search?hl=en&tbm=bks&q=editions:UGGp0EexZdcC editions:UGGp0EexZdcC] *Bolton, John. Bolton's Dictionary of Dates, arranged in alphabetical order. Foulsham. 1958. Review: [https://books.google.co.uk/books?id=awJPAAAAIAAJ 172] The Publisher 880 *[[w:William Darling (politician)|William Young Darling]]. A Book of Days: A Dictionary of Dates, a Chronology of Circumstance, the Face of Time. Richards Press. 1951. [https://books.google.co.uk/books?id=PLkfAAAAMAAJ] *Everyman's Dictionary of Dates. 1st Ed: 1911. 6th Ed: 1971. Review: (1971) 11 RQ 164 [http://www.jstor.org/stable/25824440] *Platt, Charles. Foulsham's Dictionary of Dates and General Information. 1930. *[[w:Haydn's Dictionary of Dates|Haydn's Dictionary of Dates]] *Hamlyn Dictionary of Dates and Anniversaries. Newnes Dictionary of Dates. *Williams, Henry Llewellyn. Hurst's Dictionary of Dates. 1891. [https://archive.org/details/hurstsdictionary00will] *Keller, Helen Rex. The Dictionary of Dates. Macmillan. 1934. Commentary: [https://books.google.co.uk/books?id=Utcb32E7rsMC&pg=PA93&output=html_text] [https://books.google.co.uk/books?id=sAHfY6QbOEwC&pg=PA351&output=html_text] *Nelson's Dictionary of Dates. A Dictionary of Dates. (Nelson's Encyclopaedic Library). 1912 [https://books.google.co.uk/books?id=Mp9lvwEACAAJ]. Reviews: (June 1912) Journal of Education, vol 34 (New Series), vol 44 (Old Series), p 392 [https://books.google.co.uk/books?id=QIRFAQAAMAAJ]; (1912) [https://books.google.co.uk/books?id=9i4_AQAAIAAJ 108] The Spectator [http://archive.spectator.co.uk/article/18th-may-1912/25/a-dictionary-of-dates-vol-i-and-english-idioms-nel 805] (18 May) *Pulman, George Palmer. The World's Progress: A Dictionary of Dates. New York. 1861. [https://books.google.co.uk/books?printsec=frontcover&id=k3dJAAAAYAAJ&output=html] *Urdang, Laurence. The World Almanac Dictionary of Dates. Longman. 1982. [https://books.google.co.uk/books?id=I4IRAQAAMAAJ] Review: (1982) 22 RQ 101 [http://www.jstor.org/stable/25826880] Australia *John Henniker Heaton. Australian Dictionary of Dates and Men of the Time. 1879. [https://archive.org/details/australiandicti00heatgoog] *John James Knight. In the Early Days; History and Incident of Pioneer Queensland, with Dictionary of Dates in Chronological Order. Sapsford & Co. Brisbane. 1895. America *Damon, Charles Ripley. The American Dictionary of Dates, 458-1920. R G Badger. 1921. ==Commodity dictionaries== *Statistical Classification of Domestic and Foreign Commodities Exported from the United States. Commentary: [https://books.google.co.uk/books?id=91GLhsJSBj8C&pg=PR22#v=onepage&q&f=false] [https://books.google.co.uk/books?id=RPwhAQAAMAAJ&pg=RA15-PA7#v=onepage&q&f=false] *Tovarnyi slovar'. (Commodity Dictionary). Reviews and commentary: Petrov, "Commodity Dictionary", Ekonomicheskaya Gazeta, No 13, 30 October 1961, p 45; CDSP , 13 December 1961, p 46; (1962) [https://books.google.co.uk/books?id=2vMRAAAAIAAJ 13] Current Digest of the Soviet Press 47; (1958) 15 Quarterly Journal of Current Acquisitions 210 [https://books.google.co.uk/books?id=ZcvozpZAfpEC] [https://books.google.co.uk/books?id=S47qEIfyCr0C]; Fitzpatrick, Stalinism: New Directions, [https://books.google.co.uk/books?id=rD5FzoKnTE0C&pg=PA182#v=onepage&q&f=false p 182] & 183 *Szilágyi. Commodity Dictionary in Five Languages. Budapest. Közgazdasági és Jogi Könyvkiadó (Publishing House for Economics and Law). 1963 or 1964. Commentary: Books from Hungary, vols 4-6, pp 26 & 40 [https://books.google.co.uk/books?id=6kMiAQAAMAAJ] *Dictionnaire des produits: appellations et caractéristiques des produits francais de consommation courante, 1960. Commentary: Walford (ed), Guide to Reference Material Supplement, 1963, p 106 [https://books.google.co.uk/books?id=ej-9pHGR67oC] *Chūgoku Shōhin Jiten. (Chinese commodity dictionary). Tokyo. 1960. [https://books.google.co.uk/books?id=Wc61lS0xj6AC&pg=PA78#v=onepage&q&f=false] ==Encyclopedias== See [[s:Category:Encyclopedias]], [[w:Bibliography of encyclopedias]] and [[w:Lists of encyclopedias]] *[[w:en:Encyclopædia Britannica Eleventh Edition|Encyclopædia Britannica Eleventh Edition]] *Paton, John (ed). Knowledge Encyclopedia: 1979, 1981, 1988. New Discovery Encyclopedia: 1990. *The Dorling Kindersley Illustrated Family Encyclopedia ==Almanacs== See [[s:Category:Almanacs]], [[s:Portal:Almanacs]], [[w:List of almanacs]], [[w:Category:Almanacs]]. *Year Book and Almanac of Newfoundland. **For 1896. 1895. [https://archive.org/details/yearbooknfld189600newfuoft] *Whiteley. On This Date: A Day-by-Day Listing of Holidays, Birthday and Historic Events, and Special Days, Weeks and Months. 2002. [https://books.google.co.uk/books?id=sKCfomKSa74C] ==Censuses== *Census of New Zealand and Labrador **1901 Census. Tables 2 and 3. 1903. [https://archive.org/details/censusnewfoundl00bondgoog] **1911 Census. Table 1. 1914. [https://archive.org/details/1911981911fnfldv11914eng] **1921 Census. Tables 4 and 5. 1923. [https://archive.org/details/1921981921fnfldv451923eng] ==Pilot guides== *[[w:United States Coast Pilot|United States Coast Pilot]] *American Coast Pilot [https://books.google.co.uk/books?id=8GoDAAAAYAAJ&pg=PR1#v=onepage&q&f=false] *Sailing Directions: Newfoundland. Canadian Hydrographic Service. [https://books.google.co.uk/books?id=A77fAAAAMAAJ] *Newfoundland Pilot. Canadian Hydrographic Service. [https://books.google.co.uk/books?id=z7zfAAAAMAAJ] *Maxwell. The Newfoundland Pilot. Hydrographic Office, Admiralty. London. 1878. [https://books.google.co.uk/books?id=vS4BAAAAQAAJ&pg=PR1#v=onepage&q&f=false] *Newfoundland Pilot. HO No 73. Hydrographic Office. Governement Printing Office, Washington. 4th Ed: 1919: [https://books.google.co.uk/books?id=YGoDAAAAYAAJ&pg=PP7#v=onepage&q&f=false]. Sailing Directions for Newfoundland. 5th Ed: 1931: [https://books.google.co.uk/books?id=cMUiGo3JK9QC&pg=PP5#v=onepage&q&f=false] ==Books of facts== *The Reader's Digest Book of Facts. 1st Ed: 1985. Reprinted with amendments: 1987: [https://books.google.co.uk/books?id=B8PmM_5Zm1MC]. (Review: Library Journal, [https://books.google.co.uk/books?id=EPDgAAAAMAAJ v 9], p 102, 1 Dec 1987, [http://www.bookverdict.com/details.xqy?uri=Product-94667328910921.xml Book Verdict].) 3rd Revised Ed: 1995: [https://books.google.co.uk/books?id=E5YhAQAAIAAJ]. GBooks: editions:nnJlLybWxbIC *Chambers Book of Facts *Crystal, David (ed). Penguin Book of Facts. [https://books.google.co.uk/books?id=k0sZAQAAIAAJ 2004]. 2nd Ed: 2008 *Handy Book of Facts: Things Everyone Should Know. C.S. Hammond & Company. 1914. [https://books.google.co.uk/books?id=h5wRAAAAIAAJ] ==Series of books== See [[w:Category:Series of books]] and [[w:Category:Monographic series]] *George M Sinkankas, "Series" in Kent, Lancour and Daily (eds).  Encyclopedia of Library and Information Science. Volume 27. Marcel Dekker. 1979. Pages [https://books.google.co.uk/books?id=jU3fwyjqS5UC&pg=PA250#v=onepage&q&f=false 250] to 273. *"Publishing in Series, 1896-1916" in Eliot, Simon (ed). History of Oxford University Press. Louis,  Wm Roger (ed). Volume 3: 1896-1970. Oxford University Press. 2013. [https://books.google.co.uk/books?id=YbcJAgAAQBAJ&pg=PA539#v=onepage&q&f=false Page 539] et seq. *Spiers, John. The Culture of the Publisher’s Series. Palgrave Macmillan. 2011. [https://books.google.co.uk/books?id=ASaHDAAAQBAJ&pg=PP1#v=onepage&q&f=false vol 1]. [https://books.google.co.uk/books?id=XCl-DAAAQBAJ&pg=PP1#v=onepage&q&f=false vol 2]. *Spiers, John. Serious about Series: American 'Cheap' Libraries, British 'Railway' Libraries and Some Literary Series of the 1890's. 2007. [https://books.google.co.uk/books?id=1hRXAAAAYAAJ] [https://books.google.co.uk/books?id=AS4yQwAACAAJ] *Rooney, Paul Raphael. Railway Reading and Late-Victorian Literary Series. Routledge. 2018. [https://books.google.co.uk/books?id=uX5aDwAAQBAJ&pg=PP1#v=onepage&q&f=false] *Khan. "Monographs in series". The Principles and Practice of Library Science. 1996. Pages [https://books.google.co.uk/books?id=sAHfY6QbOEwC&pg=PA208#v=onepage&q&f=false 207] to 209. *Friskney. New Canadian Library: The Ross-McClelland Years, 1952-1978. Pages [https://books.google.co.uk/books?id=jHIjCCXBX9kC&pg=PA6#v=onepage&q&f=false 6] and 7. *Books in Series. R R Bowker Company. Commentary: [https://books.google.co.uk/books?id=uQe04OSlA7YC&pg=PA11#v=onepage&q&f=false] **Books in Series in the United States, 1966-1975. R R Bowker. 1977. Review: (1977) 14 Choice [https://books.google.co.uk/books?id=_e08AQAAIAAJ&pg=PA1190#v=onepage&q&f=false 1190] (No 8, November). Commentary: [https://books.google.co.uk/books?id=LYAhAAAAQBAJ&pg=PA53#v=onepage&q&f=false] ***Books in Series Supplement: A Supplement to Books in Series in the United States, 1966-1975. 1978. [https://books.google.co.uk/books?id=hOAaAQAAMAAJ] **Books in Series. 3rd Ed. 1980. [https://books.google.co.uk/books?id=d_kaAQAAMAAJ] **Books in Series, 1876-1949. R R Bowker Company. 1982. [https://books.google.co.uk/books?id=TngvAQAAIAAJ] [https://books.google.co.uk/books?id=iVIyAQAAMAAJ] [https://books.google.co.uk/books?id=R2AjAQAAIAAJ] **Books in Series, 1985-89. [https://books.google.co.uk/books?id=yEkxAQAAIAAJ] *Baer, Eleanora Agnes. Titles in Series: A Handbook for Librarians and Students. Scarecrow Press. Vol 1 (Books Published Prior to January 1953). 1953: [https://books.google.co.uk/books?id=GgAYAAAAMAAJ]. Vol 2 (Books Published Prior to January 1957). 1957: [https://books.google.co.uk/books?id=oqsXAAAAMAAJ] **2nd Ed: 1964. [https://books.google.co.uk/books?id=gWlAAAAAIAAJ Vol 1]. [https://books.google.co.uk/books?id=tWpAAAAAIAAJ Vol 2]. Supplement to the Second Edition. 1967: [https://books.google.co.uk/books?id=zGARAQAAMAAJ]. Second Supplement to the Second Edition. 1971: [https://books.google.co.uk/books?id=WwXhAAAAMAAJ] **3rd Ed: 1978. Commentary: [https://books.google.co.uk/books?id=h_wfYKnMfOkC&pg=PA63#v=onepage&q&f=false] *Ocran, Emmanuel Benjamin. Scientific & Technical Series: A Select Bibliography. 1973: [https://books.google.co.uk/books?id=oy0EAAAAMAAJ] Review: [https://books.google.co.uk/books?id=fTCw_DQH6zkC&pg=PA949#v=onepage&q&f=false] *Rosenberg and Nichols. Young People's Books in Series: Fiction and Non-fiction, 1975-1991. Libraries Unlimited. 1992. [https://books.google.co.uk/books?id=REHhAAAAMAAJ] *Young People's Literature in Series *Catalog of Reprints in Series. (sometimes called "Catalogue of Reprints in Series"). 1940 onwards. [https://books.google.co.uk/books?id=MSI4AAAAIAAJ] [https://books.google.co.uk/books?id=6n1EAAAAMAAJ] Commentary: [https://books.google.co.uk/books?id=h_wfYKnMfOkC&pg=PA73#v=onepage&q&f=false] [https://books.google.co.uk/books?id=1RxuAAAAMAAJ] *Kuitert, Lisa. Het ene boek in vele delen. De Uitgave van Literaire Series in Nederland 1850-1900. Uitgeverij de Buitenkant. Amsterdam. 1993. Commentary: [https://books.google.co.uk/books?id=jSDnRo7YrWwC&pg=PA656#v=onepage&q&f=false] [https://books.google.co.uk/books?id=szBcAAAAMAAJ] [https://books.google.co.uk/books?id=SVcVAQAAIAAJ] [https://books.google.co.uk/books?id=R8Pfs146nUAC&pg=PA367#v=onepage&q&f=false] ==Series of classics== *Penguin Classics (Penguin Modern Classics, Penguin English Library) *Oxford World Classics *Everyman's Library *Wordsworth Classics *Macmillan Collectors Library *Bantam Classics *Minster Classics *The Literary Heritage Collection (Heron Books, London. William Collins Sons & Co, Glasgow) *Chandos Classics *Temple Classics *Longmans Heritage of Literature Series Russian *Greatest Masterpieces of Russian Literature (Heron Books, London) SF *Corgi SF Collectors Library Children's and shorter classics etc *Shorter Classics. Ginn and Company. *Ladybird Children's Classics. *Mini Classics. Parragon Books. *Bonny Books. Peter Haddock Ltd. *A series published by Dean & Son Ltd ==Non-fiction general series== *[[w:Oxford Companions|Oxford Companions]] *[[w:Cambridge Companions|Cambridge Companions]] *Princeton Companions *Blackwell Companions. Wiley Blackwell Companions *Routledge Companions. Routledge Research Companions *Ashgate Companions. Ashgate Research Companions *Brill's Companions *Facts on File Companions *Guides to Information Sources. Bowker-Saur *Butterworths Guides to Information Sources. *Columbia Guides *Blackwell Guides *Edinburgh Critical Guides *Collins Reference Dictionaries *New Horizons. Thames and Hudson. ([[w:Découvertes Gallimard|Découvertes Gallimard]]) *Collins Gem (see [[w:List of Collins GEM books]]) *Concise Encyclopedias. Collins. *Time Life Books (see [[w:Time Life#Book series]]) *[[w:Teach Yourself|Teach Yourself Books]]. English Universities Press. *[[w:Teach Yourself|Teach Yourself Books]]. Hodder and Stoughton. *Made Simple Books. W H Allen. *Palgrave Master Series *Harrap's Mini Series *Shire Albums. Shire Publications. *Fax Pax: Knowledge in a Nutshell. Fax Pax Ltd. *The Wonderful World Books. Macdonald and Company *Harper's ABC series. Includes A-B-C of Housekeeping, A-B-C of Electricity, A-B-C of Gardening and A-B-C of Manners. *Hamlyn Pocket Guides *Oxford Monograph Series *Study Outline Series. H W Wilson. [[s:Page:Russian Literature - A Study Outline.djvu/61|(wikisource)]] *Helpmate Handbooks. Willow Books University *University Paperbacks. Meuthen & Co *World Student Series. Addison Wesley *Unibooks. Hodder and Stoughton *International Student Editions. Van Nostrand Reinhold *Hutchinson University Library Imprints *Pelican Books Pictorials *Salmon Cameracolour series *Pitkin Pictorials United Kingdom *Aspects of Britain. HMSO. Places *The Little Guides. Meuthen [[s:Page:Cornwall (Salmon).djvu/336|(wikisource)]] *G.W.R. Series of Travel Books [[s:Page:The Cornwall coast.djvu/391|(wikisource)]] Art *Movements in World Art. Meuthen. *Movements in Modern Art. Meuthen. *How to Draw and Paint. New Burlington. Film *BFI Companions Popular science *Contemporary Science Paperbacks. Oliver and Boyd. *Pan Piper Science Series Science and mathematics *Simon and Schuster Tech Outlines *Schaum's Outline Series Military *Illustrated Military Guides. Illustrated Guides. "An Illustrated Guide to ...". Salamander Books. *Combat Arms. Arco Military Books. Salamander Books. Prentice Hall Press. *Osprey Men-at-Arms *Jane's Pocket Books Communication *The Library of Communication Techniques. Focal Press. *John Fiske (ed). Studies in Culture and Communication. Routledge. *The Media. Wayland. Cookery *ABC series. Peter Pauper Press. Gardening *Pan Piper Small Gardens Series. Mythology *Series on mythology published by Southwater (imprint of Anness) ==History and Geography== See also [[Universal Bibliography/History|History]] and [[Universal Bibliography/Geography|Geography]]. *Baker. Geography and History: Bridging the Divide. 2003. [https://books.google.co.uk/books?id=e8yf5JcefpAC&pg=PP1#v=onepage&q&f=false] *Darby. Relations of History and Geography: Studies in England, France and the United States. 2002. [https://books.google.co.uk/books?id=Vl4ZfpnP7NwC&pg=PP1#v=onepage&q&f=false] General series *Cambridge Studies in Historical Geography Atlases *The Times Atlas of World History *Philip's Atlas of World History History of geography: *Dunbar, Gary S. The History of Modern Geography: An Annotated Bibliography of Selected Works. Garland. 1985. [https://books.google.co.uk/books?id=FX4WAQAAIAAJ] ==Chronology== See also [[Universal Bibliography/History#Millennia, centuries and decades]] General *Chronology of World History. **Neville Williams. Chronology of the Modern World: 1763 to the present time. 1st Ed: 1966. (1763 to 1992). 2nd Ed: 1994. **Neville Williams. Chronology of the Expanding World 1492 to 1762. 1969. Reissued 1994. **Storey. Chronology of the Medieval World 800 to 1491. 1973. Reissued 1994. **Mellersh. Chronology of the Ancient World 10,000 BC to AD 799. Barrie and Jenkins. 1976. Helicon. Simon & Schuster. Reissued 1994. Centuries *Chronology of the 20th Century. Helicon. 1995. [https://books.google.com/books?id=pjsOAQAAMAAJ] *Brownstone and Franck. Timelines of the 20th Century. [https://books.google.com/books?id=IZ6SQgAACAAJ] *Beal. 20th Century Timeline. 1985. [https://books.google.com/books?id=cFrG7LBObGoC] *20th Century Day by Day [https://books.google.com/books?id=kyxaAAAAYAAJ] [https://books.google.com/books?id=WiOAAAAACAAJ] *Chronicle of the 20th Century [https://books.google.co.uk/books?id=pt3DYbnZO8sC] [https://books.google.co.uk/books?id=Gd1WPQAACAAJ] *Boyle. The Chronology of the Eighteenth and Nineteenth Centuries. 1826. [https://books.google.co.uk/books?id=wDENAAAAYAAJ&pg=PP7#v=onepage&q&f=false] Decades *Series: **Day by Day. Facts on File. [https://books.google.com/books?id=WfClvwEACAAJ] [https://books.google.com/books?id=CWNvQgAACAAJ] Years *Brown, D Kinnear. History of the Year. (1884 to 1885). [https://books.google.co.uk/books?id=DmRWAAAAYAAJ&pg=PA113#v=onepage&q&f=false Catalogue]. *The History of the Year: A Narrative of the Chief Events and Topics of Interest. [https://books.google.co.uk/books?id=ljgIAAAAQAAJ&pg=PP7#v=onepage&q&f=false 1881 to 1882]. [https://books.google.co.uk/books?id=1DgIAAAAQAAJ&pg=PP7#v=onepage&q&f=false 1882 to 1883]. *James Mason. The History of the Year 1876. [https://books.google.co.uk/books?id=6DoIAAAAQAAJ&pg=PP7#v=onepage&q&f=false] *[[w:The Annual Register|The Annual Register]]. [A View of the History Politics and Literature of the Year YYYY.] [https://books.google.co.uk/books?id=SrJNAAAAcAAJ&pg=PR1#v=onepage&q&f=false 1821]. *Giusto Traina. 428AD: An Ordinary Year at the End of the Roman Empire. [https://books.google.co.uk/books?id=gLumDwAAQBAJ&pg=PR3#v=onepage&q&f=false] Ancient *Bickerman. Chronology of the Ancient World. 1968. *Smithsonian Timelines of the Ancient World: A Visual Chronology from the Origins of Life. Dorling Kindersley. 1st American Ed: 1993. ==Anniversaries== *Sian Facer (ed). On this Day: The History of the World in 366 Days. Octopus Illustrated Publishing, London. Crescent Books, New York and Avenel. 1992: [https://books.google.com/books?id=SYGQgwHTuE0C]. Other: [https://books.google.co.uk/books?id=W687MAEACAAJ] [https://books.google.co.uk/books?id=7ujArQEACAAJ] *On this Day: A History of the World in 366 Days. DK. 2021. [https://books.google.co.uk/books?id=x4I5EAAAQBAJ&pg=PA1#v=onepage&q&f=false] ==Egyptology== *Annual Egyptological Bibliography [https://books.google.co.uk/books?id=8MoUAAAAIAAJ&pg=PR3#v=onepage&q&f=false] [https://books.google.co.uk/books?id=-eUUAAAAIAAJ&pg=PR3#v=onepage&q&f=false] ==Battlefields== *[[w:War Walks|War Walks]]. BBC2. 1996 to 1997. [Television series] *"The Times Guide to Battlefields of Britain". Day 1: The Times, 1 August 1994, p 8. Day 2: The Times, 2 August 1994, p 8. Day 3: The Times, 3 August 1994, p 6. Day 4: The Times, 4 August 1994, p 9. Day 5: The Times, 5 August 1994, p 9. Day 6: The Times, 6 August 1994, p 6. There was also a colour wall chart. ==Armed forces== Periodicals: *[[w:NATO Review|NATO Review]] Military *The Journal of Military History *Journal of the Royal United Service Institution [Google editions:lMJAgUvBWAEC editions:dcFNqS8JFjoC] *The Monthly Army List [Google editions:I0t2L4ElznEC] *The Army Quarterly and Defence Journal [Google editions:c7UjQ-q7SbUC] *Journal of the Society for Army Historical Research [Google editions:9HZkbMTl6mcC] *The Royal Armoured Corps Journal [https://www.google.com/search?tbm=bks&q=editions:dEauCcI7kssC&biw=534&bih=736&dpr=1.5#sbfbu=1] *The Royal Tank Corps Journal *The Tank [https://www.google.com/search?sa=N&cs=0&tbm=bks&q=editions:Dv-RbpoM7acC&biw=534&bih=736&dpr=1.5#ip=1] Editorial office at the Royal Tank Regiment *The Cavalry Journal [https://www.google.com/search?sa=N&cs=0&tbm=bks&q=editions:cVQlfkRl6KUC&biw=534&bih=688&dpr=1.5#sbfbu=1] *The Journal of the Royal Artillery [https://www.google.com/search?tbm=bks&q=editions:liFy4uc0ggYC&biw=534&bih=736&dpr=1.5] *Minutes of Proceedings of the Royal Artillery Institution [Google editions:wdjZ588FbtMC] *The Royal Engineers Journal [https://www.google.com/search?tbm=bks&q=editions:8XobinXLbD0C&biw=534&bih=736&dpr=1.5] *Journal of the Royal Electrical and Mechanical Engineers [https://books.google.com/books?id=dz0cmA1jnv4C] *Journal of the Royal Army Medical Corps [Google editions:FyUJx2dEWcQC] United States *Military Review *The Coast Artillery Journal [Google editions:nMCogSJ_rlkC] *Infantry Journal [Google editions:ULqoLmbUR5cC] *The Reserve Officer [Google editions:JQDRDrnD1QQC] Naval *[[w:Navy News|Navy News]] ==Armour== Armoured warfare; tank warfare *Harris and Toase. Armoured Warfare. 1990. [https://books.google.com/books?id=KYPfAAAAMAAJ] *Carver. The Apostles of Mobility: The Theory and Practice of Armoured Warfare. 1979. [https://books.google.com/books?id=8qcgAAAAMAAJ] *Fuller. Armoured Warfare: An Annotated Edition of Fifteen Lectures on Operations between Mechanized Forces. 1943. [https://books.google.co.uk/books?id=2E4tAQAAMAAJ] *Black. Tank Warfare. 2020. [https://books.google.co.uk/books?id=oFP5DwAAQBAJ&pg=PP1#v=onepage&q&f=false] *Jorgensen and Mann. Tank Warfare. 2001. [https://books.google.co.uk/books?id=0AghAQAAIAAJ] *Searle. Armoured Warfare: A Military, Political and Global History. 2017. [https://books.google.co.uk/books?id=HN4CDgAAQBAJ&pg=PP1#v=onepage&q&f=false] *Willey. Tanks: The History of Armoured Warfare. 2018. [https://books.google.com/books?id=AXTltAEACAAJ] *Perrett. Iron Fist: Classic Armoured Warfare Case Studies. [https://books.google.co.uk/books?id=pKGyeWqJcCEC]. Iron Fist: Classic Armoured Warfare. [https://books.google.co.uk/books?id=KKcKI4dG0VUC&pg=PP1#v=onepage&q&f=false] *Tom Clancy. Armoured Warfare: Guided Tour of an Armoured Cavalry Regiment. [https://books.google.co.uk/books?id=UxhONAAACAAJ] Atlas *Stephen Hart (ed). Atlas of Armored Warfare: From 1916 to the Present Day. Metro Books. 2012. [https://search.worldcat.org/title/1391166759]. Atlas of Tank Warfare. [https://books.google.com/books?id=KWqppwAACAAJ] Armored forces *Ogorkiewicz. Armoured Forces: A History of Armoured Forces and Their Vehicles. 1970. [https://books.google.co.uk/books?id=qIHfAAAAMAAJ] ==Mesoamerica== *James. Aztecs & Maya: The Ancient Peoples of Middle America. Tempus. 2001. 2005. History Press. [https://books.google.co.uk/books?id=XOXNhTY6TCYC 2009]. Reviews: "Books Received" (2003) [https://books.google.co.uk/books?id=3dozAQAAIAAJ 14] Minerva 57 (No 1); and "Overviews for the general reader" (2002) [https://books.google.co.uk/books?id=qShmAAAAMAAJ 76] Antiquity 252. *Weaver. The Aztecs, Maya, and Their Predecessors. 1972. 2nd Ed: 1981: [https://books.google.co.uk/books?id=0mQkAQAAIAAJ] [https://books.google.com/books?id=OWQkAQAAIAAJ] ==Accounting== See [[s:Category:Accounting]] Periodicals *[[s:The Accountant|The Accountant]] (1874 onwards) *Accountant's Magazine (1897 onwards) Aberdeen ==Arts== *Murray (ed).The Hutchinson Dictionary of the Arts. Helicon Publishing. 1994. Paperback Ed: 1995. Reprinted 1997. ==Biography== *Parke. Biography: Writing Lives. 2002 [https://books.google.co.uk/books?id=6bAz2K98MeYC&pg=PP1#v=onepage&q&f=false] *Caine. Biography and History. (Theory and History). 1st Ed: 2010, 2nd Ed: 2019 [https://books.google.co.uk/books?id=h3dvDwAAQBAJ&pg=PP1#v=onepage&q&f=false] Periodicals *Biography. Biography: An Interdisciplinary Quarterly. 1978 onwards. Published by the University Press of Hawaii for the Biographical Research Center. [https://books.google.co.uk/books?id=s84ZAAAAYAAJ] *Biography News. 1974 to 1975. Gale Research Company. [https://books.google.co.uk/books?id=RRsXAQAAIAAJ] Yearbooks *Current Biography Yearbook [https://books.google.com/books?id=Zcml63jalMIC] *Dictionary of Literary Biography Yearbook [https://books.google.com/books?id=gNNlAAAAMAAJ] ==Information technology== *Haynes, David (ed). Information Sources in Information Technology. (Guides to Information Sources). Bowker Saur. 1990. [https://books.google.co.uk/books?id=0hYjAAAAQBAJ&pg=PR1#v=onepage&q&f=false] ==Economics== General series: *Dryden Press Series in Economics *Hurl, Bryan (ed). Studies in the UK Economy. Heinemann Educational *Nuffield Economics & Business. Nuffield Foundation. Longman. Other: *Bannock, Baxter and Davis. The Penguin Dictionary of Economics. Penguin Books. 4th Ed: 1987. Bannock, Baxter and Rees. 1972. 2nd Ed: 1978. 3rd Ed: 1984. *Begg, Fischer and Dornbusch. Economics. McGraw Hill. 1984. 2nd Ed: 1987. 3rd Ed: 1991. *Anderton, Alain. Economics. Causeway Press. 1991. *Maile, Roger. Economics. (Core Business Studies). Mitchell Beazly. 1983. *Maunder, Myers, Wall and Miller. Economics Explained. Collins Educational. 1987. 2nd Ed: 1991. *Tibbitt, Andrew. A guide to A Level Economics. Thomas Nelson and Sons. 1986. *Lipsey, Richard G. An Introduction to Positive Economics. Weidenfeld and Nicolson. 1963. 2nd Ed: 1966. 3rd Ed: 1971. 4th Ed: 1975. 5th Ed: 1979. 6th Ed: 1983. 7th Ed: 1989. *Nicolson, Walter. Microeconomic Theory: Basic Principles and Extensions. (Dryden Press Series in Economics). Dryden Press, Holt-Saunders. 3rd Ed: 1985.  *Caves and Jones. World Trade and Payments: An Introduction. Little, Brown and Company. 1973. 1977. 3rd Ed: 1981. *National Institute of Economic and Social Research. The UK economy. (Studies in the UK Economy). Heinemann Educational. 1990. *Smith, Charles. UK trade and sterling. (Studies in the UK Economy). Heinemann Educational. 1992. ==Games== Chess *Hooper and Whyld. The Oxford Companion to Chess. Oxford University Press. 1984. Paperback: 1987. *Golombek, Harry. The Game of Chess. 1954. 2nd Ed: 1963. 3rd Ed: 1980. *Pritchard, D. Brine. The Right Way to Play Chess. 1950. 8th Ed: 1971. 10th Ed: 1974. 11th Ed: 1977. *Horowitz, Al. From Morphy to Fischer: A history of the World Chess Championship. B T Batsford. 1973. The World Chess Championship: A History. Macmillan. 1973. General series *Batsford Chess Books **Discovering Chess Series. B T Batsford. Periodicals See [[Universal Bibliography/Periodicals#Chess|Periodicals, Chess]] *British Chess Magazine Othello *Goro Hasegawa with Maxine Brady. How to Win at Othello. (A Harvest/HBJ book). Jove Publications. 1977. ISBN 0-15-642215-8. [https://books.google.co.uk/books?id=mTdhlwVeyCcC] Wargames *Battleground. Tyne Tees. (ITV). 1978. [Television]. 6 episodes, with Edward Woodward. **Laurie Taylor. "Attila the Hun invades Tyne Tees". TV Times. 1978. pp 28 & 29. **Terry Wise. "Battleground". Battle for Wargamers. June 1978. pp 261 & 262. *[[w:Game of War|Game of War]]. Channel 4. 1997. [Television]. ==Toys== Periodicals *Games & Toys: The Leading Trade Journal for Home & Export. (H Richard Simmons Limited). [https://books.google.co.uk/books?id=pMmbZ_JTnXYC] Google: editions:UO8GID_4Ck0C *Toys and Novelties. (Sporting Goods Pub Co). [https://books.google.co.uk/books?id=zKdAAQAAMAAJ] [https://archive.org/details/toys-and-novelties-volume-9-1913/page/n53/mode/1up] (Toys and Novelties Publishing Company) [https://archive.org/details/toys-and-novelties-volume-19-issue-no.-1-6-january-june-1922/page/n173/mode/1up]. Cf. "Harcourt To Buy Journals From Haire Publishing Co" [https://books.google.co.uk/books?id=J7hEAQAAIAAJ 194] Publishers Weekly 29 *[[w:Playthings (magazine)|Playthings: The National Magazine of the Toy Trade]]. (McCready Publishing Co) [https://books.google.co.uk/books?id=eCQHzuYWDY4C] [https://books.google.co.uk/books?id=mnRO5WFXDfEC]. (Geyer-McAllister Publications). Cf. "Playthings bought by Geyer-McAllister" [https://books.google.co.uk/books?id=itAaAQAAMAAJ 52] Industrial Marketing Capsule toys Gachapon *Tim Hornyak. [https://www.japantimes.co.jp/life/2017/08/19/lifestyle/gachapon-tracing-evolution-japans-colorful-toy-capsules/ Gachapon: Tracing the evolution of Japan’s colorful toy capsules]. The Japan Times. 19 August 2017. ==Cricket== See [[w:Bibliography of cricket]] *Peter Arnold and Peter Wynne-Thomas. The Complete Encyclopedia of Cricket. 2006. 4th Ed: 2011: [https://books.google.co.uk/books?id=2R_pXwAACAAJ]. **Peter Arnold. The Illustrated Encyclopedia of World Cricket. *Morgan. The Encyclopedia of World Cricket. 2007. [https://books.google.co.uk/books?id=gFCbkgEACAAJ] Scores and biographies *Marylebone Club Cricket Scores and Biographies. [https://books.google.co.uk/books?id=dl8IAAAAQAAJ&pg=PR3#v=onepage&q&f=false] **See [[w:Arthur Haygarth]] and [[w:Fred Lillywhite]] Periodicals *[[w:Cricket: A Weekly Record of the Game|Cricket: A Weekly Record of the Game]]. [https://books.google.co.uk/books?id=eX9QAAAAYAAJ&pg=PP7#v=onepage&q&f=false]. Australia *Malcolm Andrews. The Encyclopaedia of Australian Cricket. 1980. [https://catalogue.nla.gov.au/Record/1531463] *The Oxford Companion to Australian Cricket India *The Encyclopaedia of Indian Cricket, 1965. [https://books.google.com/books?id=CE4Joad6iwAC] [Includes biographies] Annuals *[[w:Indian Cricket (annual)|Indian Cricket]]. [https://books.google.co.uk/books?id=ioRLAAAAYAAJ 1966]. ===Cricketers=== Cricketers, including biographical dictionaries and collections of biographies *[[w:ESPNcricinfo|ESPNcricinfo]] *[[w:CricketArchive|CricketArchive]] *John Arlott's Book of Cricketers. 1979. [https://books.google.co.uk/books?id=8-WBAAAAMAAJ] *World Cricketers: A Biographical Dictionary [https://books.google.com/books?id=IpBLAAAAYAAJ] *Carr's Dictionary of Extraordinary Cricketers. 1977. Aurum Press. 2005. [https://books.google.com/books?id=CfwsAAAACAAJ] *Sproat. Debrett's Cricketers' Who's Who. 1980. *S Canynge Caple. The Cricketer's Who's Who. Williams. Lincoln. 1934. *Cricket Who's Who: The Cricket Blue Book. 1909. [https://catalogue.nla.gov.au/Record/119715]. 1912. Bibliography: [https://books.google.co.uk/books?id=IjQyAQAAMAAJ] *Who's Who in Test Cricket: A Biographical Dictionary of Test Cricketers [https://books.google.com/books?id=5uF5PQAACAAJ] *Frindall. England Test Cricketers: The Complete Record from 1877. 1989. [https://books.google.com/books?id=2zHYLIW7h9UC] *Brooke. The Collins Who's Who of English First-Class Cricket, 1945-1984. 1985. [https://books.google.com/books?id=NGSPAAAACAAJ]. Review: [https://books.google.co.uk/books?id=iHMsAAAAYAAJ]. Commentary: [https://books.google.co.uk/books?id=wPg5AQAAIAAJ] Gloucestershire *Gloucestershire Cricketers, 1870-1979. (ACS Cricketers Series [https://archive.acscricket.com/cricketers_series/index.html]). The Association of Cricket Statisticians. Cleethorpes. 1979. [https://archive.acscricket.com/cricketers_series/gloucestershire_cricketers_1870-1979/index.html] *Rex Pogson. Gloucestershire Cricket and Cricketers, 1919-1939. Lytham St Annes. 1944. Catalogues: [https://catalogue.nla.gov.au/Record/850643] [https://books.google.co.uk/books?id=CS83vXlB1ZIC] [https://www.worldcat.org/title/504354999]. Also printed as microfilm: [https://books.google.co.uk/books?id=iqXeDTKUEl4C]. *Dean Hayes. Gloucestershire Cricketing Greats: 46 of the Best Cricketers for Gloucestershire. Tunbridge Wells. 1990. Catalogues: [https://books.google.co.uk/books?id=OmsqAQAAIAAJ] [https://www.worldcat.org/title/25202795] Australia *The A-Z of Australian Cricketers [https://books.google.com/books?id=w-0zAAAACAAJ] *Piesse. Encyclopedia of Australian Cricket Players. 2012. [https://books.google.com/books?id=Jsh4MAEACAAJ] *C P Moody. Australian Cricket and Cricketers 1856-1893-4. Melbourne. 1894. *Jack Pollard. Australian Cricket: The Game and the Players. Hodder and Stoughton. ABC Books. Sydney. Lane Cove, New South Wales. 1982. Angus & Robertson. London. North Ryde, New South Wales. Sydney. Revised Ed: 1988. Commentary: [https://books.google.co.uk/books?id=WotYAAAAYAAJ]. Review: [https://books.google.co.uk/books?id=KzNYAAAAMAAJ]. ==Geology== *Read and Watson. Introduction to Geology. Macmillan Education. 1962. 2nd Ed: 1968. Volume 1: Principles. Volume 2: Earth History. ==Mineralogy== *Bibliography of Mineralogy for 1886. Annual Report of the Board of Regents of the Smithsonian Institution. Year Ending 30 June 1887. 1889. Pages [https://books.google.co.uk/books?id=wDcWAAAAYAAJ&pg=PA473#v=onepage&q&f=false 473] to 476. *Battey, Maurice Hugh. Mineralogy for students. Oliver & Boyd. 1972. 2nd Ed. Longman. 1981. ==Paper== See [[s:Category:Paper]] *Surface. Bibliography of the Pulp and Paper Industries. Forest Service. Bulletin 123. 1913. [https://archive.org/details/bibliographyofpu12surf] *West. Reading List on Papermaking Materials. 1920 to 1921. [https://archive.org/details/readinglistonpa00westgoog] [https://archive.org/details/readinglistonpa01westgoog] ==Books== *British Book News [https://books.google.co.uk/books?id=2oFTAAAAIAAJ] *Australasian Book News and Literary Journal. Australasian Book News and Library Journal. [https://books.google.co.uk/books?id=QVQPAQAAIAAJ] *Book News. 1882 to 1918. (John Wanamaker). Called "Book News Monthly" from 1906. [https://books.google.co.uk/books?id=KtwRAAAAYAAJ&pg=PP7#v=onepage&q&f=false] *Stechert-Hafner Book News [https://books.google.co.uk/books?id=BmDqAAAAMAAJ] *U.S.A. Book News [https://books.google.co.uk/books?id=36gVAQAAIAAJ] *Branch Library Book News. [https://books.google.co.uk/books?id=NM8aAAAAMAAJ] *Hungarian Book Review [https://books.google.co.uk/books?id=6U85AQAAIAAJ] *Soviet Book News. (Earl Browder). 1947 [https://books.google.co.uk/books?id=QrXQ6LYSOF4C] *Miniature Book News. [https://books.google.co.uk/books?id=MascAQAAMAAJ] Rare *Berger. Rare Books and Special Collections. American Library Association. 2014. [https://books.google.co.uk/books?id=IFUangEACAAJ] Printed *Annual Bibliography of the History of the Printed Book and Libraries. [https://books.google.co.uk/books?id=GLigoebhrd8C&pg=PP1#v=onepage&q&f=false vol 30] [https://books.google.co.uk/books?id=UBN-IUZlF4gC&pg=PP1#v=onepage&q&f=false vol 31] ==Paperback and Paperbound== *Swados, "Paper Books: What do they Promise?" (1953) [https://books.google.co.uk/books?id=TwaJtQzwj1gC 173] The Nation 114 *Wagman, "The Paperbound Book Business" (1957) 9 Michigan Business Review [https://books.google.co.uk/books?id=9pA8uolQjnkC&pg=RA4-PA9#v=onepage&q&f=false 9] (No 5, November) ==Science== *Lafferty and Rowe. The Hutchinson Dictionary of Science. Helicon Publishing. 1993. 2nd Ed: 1998. ==Entertainment== *The Directory (The Times, 1996 onwards) Commentary: [https://www.marketingweek.com/as-times-starts-listings-supplement/] ==Fiction== ===Characters=== *Bowker's Guide to Characters in Fiction [https://books.google.co.uk/books?id=rVjlAAAAMAAJ] *William Freeman. Dictionary of Fictional Characters. [https://books.google.co.uk/books?id=sRYuAAAAMAAJ] *Martin Seymour-Smith. Dictionary of Fictional Characters. The Writer, Inc. [https://books.google.co.uk/books?id=MoQYAAAAIAAJ] *Cyclopedia of Literary Characters. Salem Press. Rev Ed: 1998. [https://books.google.co.uk/books?id=IJMYAAAAIAAJ] *Larousse Dictionary of Literary Characters. [https://books.google.co.uk/books?id=hq4UAQAAIAAJ] *Chambers Dictionary of Literary Characters. [https://books.google.com/books?id=KWNMPwAACAAJ] *Michael D Sollars. Dictionary of Literary Characters. [https://books.google.co.uk/books?id=IJddAQAACAAJ] ==Comedy and tragedy== *E H Mikhail. Comedy and Tragedy: A Bibliography of Critical Studies. 1972. [https://books.google.co.uk/books?id=5bgEAAAAMAAJ] ===Comedy=== *James E Evans. Comedy: An Annotated Bibliography of Theory and Criticism. 1987. [https://books.google.co.uk/books?id=s9ZgthAs1t8C&pg=PP1#v=onepage&q&f=false] *Meghan Duffy (ed). Daniel Gerould (senior ed). Comedy: A Bibliography of Critical Studies in English on the Theory and Practice of Comedy in Drama, Theatre, and Performance. New York. 2006. [https://books.google.co.uk/books?id=fI0jAQAAIAAJ] *David Humphrey. The Time of Laughter: Comedy and the Media Cultures of Japan. University of Michigan Press. 2023. [https://books.google.co.uk/books?id=CkTLEAAAQBAJ&pg=PP1#v=onepage&q&f=false] ==Radio and television== *William E McCavitt. Radio and Television: A Selected Annotated Bibliography. Scarecrow Press. 1978. [https://books.google.com/books?id=DAQVAQAAIAAJ] *Gertrude G Broderick. Radio and Television Bibliography. Bulletin 1948 No 17. [https://books.google.co.uk/books?id=yIPP1dsmNtAC&pg=PP5#v=onepage&q&f=false] *Patricia Beall Hamill. Radio and Television: A Selected Bibliography. Bulletin 1960 No 25. [https://books.google.co.uk/books?id=AJhGAQAAMAAJ&pg=PP3#v=onepage&q&f=false] ==Film and television== *Jean Mitry. Bibliographie internationale du cinéma et de la télévision. 1966 onwards. [https://books.google.co.uk/books?id=SC3gAAAAMAAJ] Commentary: A Reference Guide for English Studies, [https://books.google.co.uk/books?id=h_wfYKnMfOkC&pg=PA439#v=onepage&q&f=false p 439]. ==Broadcasting== *Iwao Nakajima. The Broadcasting Industry in Japan: Its Historical, Legal and Economic Aspects. (International Studies of Broadcasting). NHK Radio and TV Culture Research Institute. 1971. [https://books.google.co.uk/books?id=uZ4vAQAAIAAJ] *50 Years of Japanese Broadcasting. NHK. 1977. [https://books.google.com/books?id=FoSKqY7tG-AC] *The History of Broadcasting in Japan. Nippon Hoso Kyokai. 1967. [https://books.google.com/books?id=I1IHAQAAIAAJ] *Hitoshi Mitomo and Mikio Kimura. Broadcasting in Japan: Challenges and Opportunities. [https://books.google.co.uk/books?id=7hCcEAAAQBAJ&pg=PP1#v=onepage&q&f=false] *Broadcasting in Japan: Case-studies on Broadcasting Systems. 1978. 2011. [https://books.google.co.uk/books?id=Ez5ZBwAAQBAJ&pg=PR4#v=onepage&q&f=false] *"World's First TV Stereo Broadcasts in Japan". Japan Report. (vol 25, no 3). 1 February 1979. p 4. *Broadcasting in Japan: A Historical Review [https://books.google.com/books?id=uDYlAAAAMAAJ] Annuals *[[w:ja:日本民間放送年鑑|日本民間放送年鑑]] (Japan Commercial Broadcasting Yearbook). コーケン出版. [https://books.google.co.uk/books?id=vh22AAAAIAAJ 1997]. ==Animation== *John Halas and Roger Manvell. The Technique of Film Animation. 4th Ed: 1976. Focal Press. ISBN 0240509005. *Clements and McCarthy. The Anime Encyclopedia. 3rd Rev Ed: [https://books.google.co.uk/books?id=E03KBgAAQBAJ&pg=PA1958#v=onepage&q&f=false]. *[https://www.bloomberg.com/news/articles/2026-10-07/anime-s-popularity-is-rising-among-teen-fans Anime is winning over a new generation of fans]. Bloomberg. 9 October 2026. [https://www.japantimes.co.jp/culture/2026/10/09/entertainment-news/anime-survey-watching/ The Japan Times]. ==Colours== *Eiseman and Recker. Pantone: The 20th Century in Color. [https://books.google.co.uk/books?id=j3H7nSVS3UMC&pg=PP1#v=onepage&q&f=false]. Reviews: [https://www.theguardian.com/books/2011/nov/13/pantone-20th-century-color-review][https://www.theatlantic.com/entertainment/archive/2011/11/pantone-100-years-of-color/249016/][https://eu.vvdailypress.com/story/lifestyle/health-fitness/2012/01/16/color-reel-20th-century-s/37119883007/] ==Bilateral== Britain and Japan *Pearse. Companion to Japanese Britain and Ireland. In Print. 1991. [https://books.google.co.uk/books?id=KtAxAAAAIAAJ] ==Prehistoric life== Prehistoric animals *[[w:Michael Benton|Michael Benton]]. Prehistoric Animals: An A-Z Guide. Kingfisher Books. 1989. Derrydale Books, New York. 1989. [Illustrations: Jim Channell and Kevin Maddison.] *Ellis Owen. Prehistoric Animals: The Extraordinary Story of Life before Man. Octopus Books Limited. London. 1975. [Sculptures: Arthur Hayward.] Review: [https://books.google.co.uk/books?id=II-B8R-8Ov8C 17] Wildlife 422. Commentary: [https://books.google.co.uk/books?id=aUbYAAAAQBAJ&pg=PA269#v=onepage&q&f=false] [https://books.google.co.uk/books?id=jFNBAAAAIBAJ&pg=PA5#v=onepage&q&f=false]. **Prehistorische dieren: de geschiedenis van het leven vóór de mens. Translated by JJ Hoedeman. In den Toren, Baarn. Westland, Schoten. 1977. Commentary: [https://books.google.co.uk/books?id=ToVMAQAAIAAJ] **Les Animaux préhistoriques: l'extraordinaire histoire de la vie avant l'homme. Dinosaurs *Michael Benton. Dinosaurs: An A-Z Guide. Kingfisher Books. 1988. Derrydale Books, New York. 1988. [Illustrations: Jim Channell and Kevin Maddison.] ==Regions and other places== *JD Pearson. Oriental and Asian Bibliography: An Introduction with Some Reference to Africa. Archon Books. [https://books.google.com/books?id=P18ZAAAAMAAJ] *Theodore Besterman. A World Bibliography of Oriental Bibliographies. Revised by JD Pearson. Rowman and Littlefield. [https://books.google.co.uk/books?id=dvnfAAAAMAAJ] ==Culture and society== *Victoria Lyon Bestor, Theodore C Bestor and Akiko Yamagata (eds). Routledge Handbook of Japanese Culture and Society. 2011. [https://books.google.co.uk/books?id=0cBYffHp5L4C&pg=PP1#v=onepage&q&f=false] *Josef Kreiner and Hans-Dieter Ölschleger (eds). Japanese Culture and Society: Models of Interpretation. 1996. [https://books.google.co.uk/books?id=6skwAQAAIAAJ] *Dolores P Martinez. Modern Japanese Culture and Society. 2007. [https://books.google.co.uk/books?id=l6kMAQAAMAAJ vol 1] *C Andrew Gerstle. 18th Century Japan: Culture and Society. 1989. [https://books.google.co.uk/books?id=ViglDwAAQBAJ&pg=PP1#v=onepage&q&f=false] Periodicals *Review of Japanese Culture and Society [https://books.google.co.uk/books?id=W_o-AQAAIAAJ] ==Clothes== *John Marshall. Make Your Own Japanese Clothes: Patterns and Ideas for Modern Wear. Kodansha International. 1988. [https://books.google.co.uk/books?id=ljOuuy0OO0UC&pg=PP1#v=onepage&q&f=false] ==Fashion== *Toby Slade. Japanese Fashion: A Cultural History. 2009. [https://books.google.co.uk/books?id=AInI19E48QIC&pg=PP3#v=onepage&q&f=false] *Bonnie English. Japanese Fashion Designers: The Work and Influence of Issey Miyake, Yohji Yamamotom, and Rei Kawakubo. 2011. [https://books.google.co.uk/books?id=6UMfAAAAQBAJ&pg=PP1#v=onepage&q&f=false] *Sadao Hibi. Japanese Detail Fashion. Chronicle Books. 1989. [https://books.google.com/books?id=G-kIAQAAMAAJ] **Nihon No Dento Iro To Katachi. Graphic-sha Publishing. 1987. *Clémence Leleu. Japanese Fashion: A Journey from Tradition to Iconic Designers, Street Style to Global Influence. Translated by Andrea Reece. 2026. [https://books.google.co.uk/books?id=j2_MEQAAQBAJ&pg=PA1#v=onepage&q&f=false] **Mode Japonaise. 2025. Kimono *Sheila Cliffe. The Social Life of Kimono: Japanese Fashion Past and Present. 2017. [https://books.google.co.uk/books?id=7G6xDQAAQBAJ&pg=PP1#v=onepage&q&f=false] *Anna Jackson (ed). Kimono: The Art and Evolution of Japanese Fashion. V&A Publishing. 2010. [https://books.google.co.uk/books?id=8gtMAQAAIAAJ]. Catalogue: [https://search.worldcat.org/title/kimono-the-art-and-evolution-of-japanese-fashion-the-khalili-collections/oclc/917375803]. ==Documents== *Pages from History: Ten Documents that changed the World AD 1000 to AD 2000. The Sunday Times. (10 pull out supplements and folder). *Scott Christianson. 100 Documents That Changed the World: From Magna Carta to WikiLeaks. [https://books.google.co.uk/books?id=rxiUEAAAQBAJ&pg=PA1#v=onepage&q&f=false] *Joseph Janes. Documents That Changed the Way We Live. 2017. [https://books.google.co.uk/books?id=a6-zDgAAQBAJ&pg=PP1#v=onepage&q&f=false] *Graham Stewart. Britannia: 100 Documents that Shaped a Nation. [https://books.google.co.uk/books?id=XUuL3xyZ9k8C&pg=PA1#v=onepage&q&f=false] ==See also== *[[Bibliography]] ==Notes== {{Reflist}} {{subpagesif}} [[Category:Bibliographies]] [[Category:Research]] aplun2pi2jwm3er00i1qemet9vevk2a 1 171302 2844890 2844144 2026-11-08T18:23:13Z James500 297601 /* */ Add 2844890 wikitext text/x-wiki Terms that sometimes appear in the titles of bibliographies, guides to literature/reference, etc: Bibliography, catalogue, guide, list, index, in print, books, literature, sources, works, material, titles, reference. [[User:James500|James500]] ([[User talk:James500|discuss]] • [[Special:Contributions/James500|contribs]]) 13:54, 14 November 2020 (UTC) For future use: *Non-fiction, art, fine arts, music, painting, sculpture, government, politics, philosophy, theology, religion, agriculture, forestry, fisheries, mining, manufacturing, technology, computer science, engineering, astronomy, physics, chemistry, biology, botany, natural history, prehistory, classics, anthropology, library science, librarianship, information studies, places, exploration, transport, Earth science, paleontology, official publications, universities, museums *Reprography, lithography, engraving *Bookbinding, early printed books, incunabula, manuscripts, papyri, papyrology *Languages, philology, ancient languages, medieval languages, dead languages, extinct languages *Writing, scripts, decipherment, alphabets, hieratic, demotic, hieroglyphic, figurative, ideographic, pictographic, cuneiform, inscriptions, stelae [stela], clay tablets, ostraka [ostrakon], papyrus, Minoan scripts, Linear A, Linear B *Indo-European languages; Italo-Celtic; Celtic languages *Latin, Greek, middle english, old english, anglo-norman [anglo-french], old french, old norse, old welsh, middle welsh, egyptian, hittite, luwian, lycian, akkadian, assyro-babylonian, elamite, amorite *Special libraries, national libraries, public libraries, university libraries, college libraries, school libraries, museum libraries *Archaeological theory, methodology, geology, stratigraphy etc. Field archaeology, behavioural archaeology *Tide tables *George Watson (ed). The Cambridge Bibliography of English Literature. Cambridge University Press. 1966. Volume 5. [https://books.google.co.uk/books?id=ebM6AAAAIAAJ] *[[s:Page:Cornwall (Mitton).djvu/230|"Some Books on Cornwall"]] *[[s:Author:Richard Colt Hoare]] *Yorkshire literature *Catalogues régionaux des incunables des bibliothèques publiques de France. [https://books.google.co.uk/books?id=K38VcZrjrj0C&pg=PA1#v=onepage&q&f=false] (regional catalogues of incunabula in the public libraries of France) * [[User:James500|James500]] ([[User talk:James500|discuss]] • [[Special:Contributions/James500|contribs]]) 16:24, 24 November 2019 (UTC) For future use: *Palmer's Index to The Times **editions:2Faf22c-dSwC *Routledge Handbook of Soviet and Russian Military Studies France: *Les Dictionnaires départementaux.  [https://books.google.co.uk/books?id=FZEwAQAAMAAJ] (series includes departmental biographical dictionaries) Creuse: *Guide des archives de la Creuse. 1972 [https://books.google.co.uk/books?id=eEsCAAAAMAAJ] *Joanne. Géographie du département de la Creuse. 1895 [https://books.google.co.uk/books?id=izeVfoPbIc8C] *Jamain. Le département de la Creuse: ses origines et sa pérennité [https://books.google.co.uk/books?id=kY-KMwcsJMEC&pg=PP1#v=onepage&q&f=false] *Annuaire du Département de la Creuse [https://books.google.co.uk/books?id=7wpBAAAAcAAJ&pg=PA1#v=onepage&q&f=false] *Journal du département de la Creuse (1807-1819) Bibliography: *[[w:Fredson Bowers|Bowers, Fredson]]. Principles of Bibliographical Description. Princeton University Press. 1949. Russell & Russell, New York. 1962. St Paul's Bibliographies (No 15). 1986. [https://books.google.co.uk/books?id=hA7hAAAAMAAJ] Commentary: [https://books.google.co.uk/books?id=Utcb32E7rsMC&pg=PA525#v=onepage&q&f=false] *Bowers, Fredson. Bibliography and Textual Criticism. Clarendon Press, Oxford. 1964. [https://books.google.co.uk/books?id=zOFhNcQsihAC] Series: *Studies in Bibliography. Formerly "Papers in Bibliography". (Bibliographical Society of the University of Virginia). (1948 onwards) [https://books.google.co.uk/books?id=HGEUAAAAIAAJ] Commentary: "A History of Studies in Bibliography: The First Fifty Volumes" in The First Fifty Years, p 125 [https://books.google.co.uk/books?id=ZukVAQAAIAAJ] **Tanselle. Selected Studies in Bibliography. (Bibliographical Society of the University of Virginia) [https://books.google.co.uk/books?id=OnktAQAAIAAJ] Commentary: [https://books.google.co.uk/books?id=Utcb32E7rsMC&pg=PA526#v=onepage&q&f=false] Library associations: *IFLA. Functional Requirements for Bibliographic Records: Final Report. Saur. 1998. [https://books.google.co.uk/books?id=YW8hAAAAQBAJ&pg=PP4#v=onepage&q&f=false] *Patrick Le Boeuf (ed). Functional Requirements for Bibliographic Records (FRBR): Hype or Cure-All? Haworth Press. 2005. Routledge. 2013 [https://books.google.co.uk/books?id=Ka7hAQAAQBAJ&pg=PP1#v=onepage&q&f=false] *Guidelines for Bibliographic Description of Reproductions. American Library Association. 1995. [https://books.google.co.uk/books?id=9zG6MGudKv8C&lpg=PP1&pg=PP1#v=onepage&q&f=false] Serials: *Serials Review Nostgia *Nostalgia cycles: [https://slate.com/culture/2012/04/the-golden-forty-year-rule-and-other-nostalgia-cycles-could-trends-possibly-return-every-40-years-20-years-and-12-15-years.html] [https://www.vice.com/en/article/how-the-20-year-trend-cycle-collapsed/] [https://www.npr.org/2022/03/01/1081115609/from-tumblrcore-to-2014core-the-nostalgia-loop-is-getting-smaller-and-faster] [https://www.theguardian.com/music/2023/apr/20/lets-go-round-again-the-ridiculous-rise-of-fifth-anniversary-vinyl-reissues] [https://www.independent.co.uk/life-style/fashion/gen-z-fashion-trends-tumblr-aesthetic-b2042247.html] *Stuck in the Seventies: 113 Things from the 1970s that Screwed Up the Twentysomething Generation. 1991. 1995. [https://books.google.co.uk/books?id=bZ03g5ylsaEC]. Review: [https://books.google.co.uk/books?id=6V4cAQAAMAAJ]. *1969: [https://books.google.co.uk/books?id=yuwjAAAAIBAJ&pg=PA25#v=onepage&q&f=false]. *[https://books.google.co.uk/books?id=COhVAAAAIBAJ&pg=PA20#v=onepage&q&f=false] [https://books.google.co.uk/books?id=Xf4rAAAAIBAJ&pg=PA3#v=onepage&q&f=false] [https://books.google.co.uk/books?id=nFtWAAAAIBAJ&pg=PA31#v=onepage&q&f=false] [https://books.google.co.uk/books?id=HqkfAAAAIBAJ&pg=PA27&article_id=4890,1282350#v=onepage&q&f=false] [https://books.google.co.uk/books?id=_WZGAAAAIBAJ&pg=PA29#v=onepage&q&f=false][https://books.google.co.uk/books?id=bzpHAAAAIBAJ&pg=PA27#v=onepage&q&f=false][https://books.google.co.uk/books?id=s1MgAAAAIBAJ&pg=PA7#v=onepage&q&f=false] *1970s: [https://books.google.co.uk/books?id=YT5QAAAAIBAJ&pg=PA8#v=onepage&q&f=false] *1990s Tamagotchi [https://www.nssmag.com/en/lifestyle/38204/tamagotchi-y2k-nostalgia] *[https://www.bbc.co.uk/programmes/m002g6k5 90s Nostalgia]. BBC. *[https://www.rd.com/article/tv-shows-like-stranger-things/ Stranger Things Is Over—Now What?! Here Are 7 Shows to Watch to Fill the Void]. Reader's Digest. 1 January 2026. *Anne Latreille. [https://trove.nla.gov.au/newspaper/article/47808279 "There's a Boom in Nostalgia"]. [[w:The Australian Women's Weekly|The Australian Women's Weekly]]. 29 March 1972. p 7. *The Past in the Present: Proceedings of the 5th Annual British and Cultural Studies Conference, Oldenburg 1994 Other *[[w:Haruko Ichikawa|Haruko Ichikawa]] (市河晴子 or 市川晴子) (1896-1943) **Japanese Lady in Europe. 1937. [https://books.google.co.uk/books?id=xi42AAAAMAAJ] (Japanese: 欧米の隅々) **Japanese Lady in America. First published 1938. [https://books.google.com/books?id=KQY7AQAAIAAJ] (Japanese: 米国の旅日本の旅) Search terms: *"press in japan" *"japanese press" *"press of japan" *"journalism of japan" *"journalism in japan" *"journalists in japan" *"japanese journalism" Generations *[https://www.vox.com/2018/8/15/17686668/millennials-explained Stop calling teenagers millennials]. Vox. 15 August 2018. Planet Earth *[[w:Encyclopedia of Earth|Encyclopedia of Earth]] Crime *The Concise Encyclopedia of Crime and Criminals [https://books.google.co.uk/books?id=uGTQAAAAIAAJ] Showa era *懐かしの昭和・平成流行事典: 2001-1945. [[w:ja:新人物往来社|Shin-Jinbutsuoraisha]]. 2002. [https://books.google.co.uk/books?id=QCYyAQAAIAAJ] *少年ブーム～昭和レトロの流行もの. 串間努著. 2003. [https://books.google.co.uk/books?id=sK0nAQAAIAAJ] Fading of the Showa era *[https://www.theguardian.com/world/gallery/2025/dec/02/fading-japan-showa-era-in-pictures The fading of Japan’s Shōwa era – in pictures]. The Guardian. 2 December 2025. *[https://soranews24.com/2026/04/02/fading-tokyo-searching-for-signs-of-the-showa-era-as-local-neighborhoods-evolvephotos/ Fading Tokyo – Searching for signs of the Showa era as local neighborhoods evolve]. SoraNews24. 2 April 2026. Showa retro packaging *[[w:ja:初見健一|Kenichi Hatsumi]]. 昭和のレトロパッケージ. [[w:ja:グラフィック社|Graphic-sha]]. 2016. ISBN 9784766128741. [https://books.google.co.uk/books?id=Ch5wjwEACAAJ] Shotengai *[https://www.theguardian.com/world/2025/jul/18/cult-of-convenience-how-tokyos-retro-shotengai-arcades-are-falling-victim-to-gentrification ‘Cult of convenience’: how Tokyo’s retro shotengai arcades are falling victim to gentrification]. The Guardian. 18 July 2025. Shakespeare *Demmon (compiler). Catalogue of the Shakespearian Books and Pamphlets in the Joseph Crosby Library. 1885. [https://books.google.co.uk/books?id=GSZLAQAAMAAJ&pg=PA1#v=onepage&q&f=false]. *Shakespeare the Man and the Book. Part 2: Occasional Papers. 1881. [https://books.google.co.uk/books?id=gfUUAAAAYAAJ&pg=PP11#v=onepage&q&f=false] *Best films: [https://www.empireonline.com/movies/features/best-movies-of-all-time-us/] Survivability of past atmosphere *[https://news.climate.columbia.edu/2022/09/20/you-asked-dinosaurs-survived-when-co2-was-extremely-high-why-cant-humans/ You Asked: Dinosaurs Survived When CO2 Was Extremely High. Why Can’t Humans?] Columbia Climate School. 20 September 2022. *[https://www.sciencefocus.com/planet-earth/how-far-back-in-time-would-we-be-able-to-go-and-still-breathe-our-planets-air How far back in time would we be able to go and still breathe our planet's air?] BBC Science Focus. *[https://gizmodo.com/the-one-basic-fact-about-history-that-time-travelers-al-1652649190 The One Basic Fact About History That Time Travelers Always Forget]. io9. Gizmodo. 31 October 2014. Philology *W Pökel. Philologisches Schriftsteller-Lexikon. 1882. [https://books.google.co.uk/books?id=2jAaAAAAMAAJ&pg=PR1#v=onepage&q&f=false] [[User:James500|James500]] ([[User talk:James500|discuss]] • [[Special:Contributions/James500|contribs]]) 10:55, 26 October 2020 (UTC) fvf03uzufj9gsp02p2gqeqo1h51uxwd 2844891 2844890 2026-11-08T18:26:22Z James500 297601 /* */ Add 2844891 wikitext text/x-wiki Terms that sometimes appear in the titles of bibliographies, guides to literature/reference, etc: Bibliography, catalogue, guide, list, index, in print, books, literature, sources, works, material, titles, reference. [[User:James500|James500]] ([[User talk:James500|discuss]] • [[Special:Contributions/James500|contribs]]) 13:54, 14 November 2020 (UTC) For future use: *Non-fiction, art, fine arts, music, painting, sculpture, government, politics, philosophy, theology, religion, agriculture, forestry, fisheries, mining, manufacturing, technology, computer science, engineering, astronomy, physics, chemistry, biology, botany, natural history, prehistory, classics, anthropology, library science, librarianship, information studies, places, exploration, transport, Earth science, paleontology, official publications, universities, museums *Reprography, lithography, engraving *Bookbinding, early printed books, incunabula, manuscripts, papyri, papyrology *Languages, philology, ancient languages, medieval languages, dead languages, extinct languages *Writing, scripts, decipherment, alphabets, hieratic, demotic, hieroglyphic, figurative, ideographic, pictographic, cuneiform, inscriptions, stelae [stela], clay tablets, ostraka [ostrakon], papyrus, Minoan scripts, Linear A, Linear B *Indo-European languages; Italo-Celtic; Celtic languages *Latin, Greek, middle english, old english, anglo-norman [anglo-french], old french, old norse, old welsh, middle welsh, egyptian, hittite, luwian, lycian, akkadian, assyro-babylonian, elamite, amorite *Special libraries, national libraries, public libraries, university libraries, college libraries, school libraries, museum libraries *Archaeological theory, methodology, geology, stratigraphy etc. Field archaeology, behavioural archaeology *Tide tables *George Watson (ed). The Cambridge Bibliography of English Literature. Cambridge University Press. 1966. Volume 5. [https://books.google.co.uk/books?id=ebM6AAAAIAAJ] *[[s:Page:Cornwall (Mitton).djvu/230|"Some Books on Cornwall"]] *[[s:Author:Richard Colt Hoare]] *Yorkshire literature *Catalogues régionaux des incunables des bibliothèques publiques de France. [https://books.google.co.uk/books?id=K38VcZrjrj0C&pg=PA1#v=onepage&q&f=false] (regional catalogues of incunabula in the public libraries of France) * [[User:James500|James500]] ([[User talk:James500|discuss]] • [[Special:Contributions/James500|contribs]]) 16:24, 24 November 2019 (UTC) For future use: *Palmer's Index to The Times **editions:2Faf22c-dSwC *Routledge Handbook of Soviet and Russian Military Studies France: *Les Dictionnaires départementaux.  [https://books.google.co.uk/books?id=FZEwAQAAMAAJ] (series includes departmental biographical dictionaries) Creuse: *Guide des archives de la Creuse. 1972 [https://books.google.co.uk/books?id=eEsCAAAAMAAJ] *Joanne. Géographie du département de la Creuse. 1895 [https://books.google.co.uk/books?id=izeVfoPbIc8C] *Jamain. Le département de la Creuse: ses origines et sa pérennité [https://books.google.co.uk/books?id=kY-KMwcsJMEC&pg=PP1#v=onepage&q&f=false] *Annuaire du Département de la Creuse [https://books.google.co.uk/books?id=7wpBAAAAcAAJ&pg=PA1#v=onepage&q&f=false] *Journal du département de la Creuse (1807-1819) Bibliography: *[[w:Fredson Bowers|Bowers, Fredson]]. Principles of Bibliographical Description. Princeton University Press. 1949. Russell & Russell, New York. 1962. St Paul's Bibliographies (No 15). 1986. [https://books.google.co.uk/books?id=hA7hAAAAMAAJ] Commentary: [https://books.google.co.uk/books?id=Utcb32E7rsMC&pg=PA525#v=onepage&q&f=false] *Bowers, Fredson. Bibliography and Textual Criticism. Clarendon Press, Oxford. 1964. [https://books.google.co.uk/books?id=zOFhNcQsihAC] Series: *Studies in Bibliography. Formerly "Papers in Bibliography". (Bibliographical Society of the University of Virginia). (1948 onwards) [https://books.google.co.uk/books?id=HGEUAAAAIAAJ] Commentary: "A History of Studies in Bibliography: The First Fifty Volumes" in The First Fifty Years, p 125 [https://books.google.co.uk/books?id=ZukVAQAAIAAJ] **Tanselle. Selected Studies in Bibliography. (Bibliographical Society of the University of Virginia) [https://books.google.co.uk/books?id=OnktAQAAIAAJ] Commentary: [https://books.google.co.uk/books?id=Utcb32E7rsMC&pg=PA526#v=onepage&q&f=false] Library associations: *IFLA. Functional Requirements for Bibliographic Records: Final Report. Saur. 1998. [https://books.google.co.uk/books?id=YW8hAAAAQBAJ&pg=PP4#v=onepage&q&f=false] *Patrick Le Boeuf (ed). Functional Requirements for Bibliographic Records (FRBR): Hype or Cure-All? Haworth Press. 2005. Routledge. 2013 [https://books.google.co.uk/books?id=Ka7hAQAAQBAJ&pg=PP1#v=onepage&q&f=false] *Guidelines for Bibliographic Description of Reproductions. American Library Association. 1995. [https://books.google.co.uk/books?id=9zG6MGudKv8C&lpg=PP1&pg=PP1#v=onepage&q&f=false] Serials: *Serials Review Nostgia *Nostalgia cycles: [https://slate.com/culture/2012/04/the-golden-forty-year-rule-and-other-nostalgia-cycles-could-trends-possibly-return-every-40-years-20-years-and-12-15-years.html] [https://www.vice.com/en/article/how-the-20-year-trend-cycle-collapsed/] [https://www.npr.org/2022/03/01/1081115609/from-tumblrcore-to-2014core-the-nostalgia-loop-is-getting-smaller-and-faster] [https://www.theguardian.com/music/2023/apr/20/lets-go-round-again-the-ridiculous-rise-of-fifth-anniversary-vinyl-reissues] [https://www.independent.co.uk/life-style/fashion/gen-z-fashion-trends-tumblr-aesthetic-b2042247.html] *Stuck in the Seventies: 113 Things from the 1970s that Screwed Up the Twentysomething Generation. 1991. 1995. [https://books.google.co.uk/books?id=bZ03g5ylsaEC]. Review: [https://books.google.co.uk/books?id=6V4cAQAAMAAJ]. *1969: [https://books.google.co.uk/books?id=yuwjAAAAIBAJ&pg=PA25#v=onepage&q&f=false]. *[https://books.google.co.uk/books?id=COhVAAAAIBAJ&pg=PA20#v=onepage&q&f=false] [https://books.google.co.uk/books?id=Xf4rAAAAIBAJ&pg=PA3#v=onepage&q&f=false] [https://books.google.co.uk/books?id=nFtWAAAAIBAJ&pg=PA31#v=onepage&q&f=false] [https://books.google.co.uk/books?id=HqkfAAAAIBAJ&pg=PA27&article_id=4890,1282350#v=onepage&q&f=false] [https://books.google.co.uk/books?id=_WZGAAAAIBAJ&pg=PA29#v=onepage&q&f=false][https://books.google.co.uk/books?id=bzpHAAAAIBAJ&pg=PA27#v=onepage&q&f=false][https://books.google.co.uk/books?id=s1MgAAAAIBAJ&pg=PA7#v=onepage&q&f=false] *1970s: [https://books.google.co.uk/books?id=YT5QAAAAIBAJ&pg=PA8#v=onepage&q&f=false] *1990s Tamagotchi [https://www.nssmag.com/en/lifestyle/38204/tamagotchi-y2k-nostalgia] *[https://www.bbc.co.uk/programmes/m002g6k5 90s Nostalgia]. BBC. *[https://www.rd.com/article/tv-shows-like-stranger-things/ Stranger Things Is Over—Now What?! Here Are 7 Shows to Watch to Fill the Void]. Reader's Digest. 1 January 2026. *Anne Latreille. [https://trove.nla.gov.au/newspaper/article/47808279 "There's a Boom in Nostalgia"]. [[w:The Australian Women's Weekly|The Australian Women's Weekly]]. 29 March 1972. p 7. *The Past in the Present: Proceedings of the 5th Annual British and Cultural Studies Conference, Oldenburg 1994 Other *[[w:Haruko Ichikawa|Haruko Ichikawa]] (市河晴子 or 市川晴子) (1896-1943) **Japanese Lady in Europe. 1937. [https://books.google.co.uk/books?id=xi42AAAAMAAJ] (Japanese: 欧米の隅々) **Japanese Lady in America. First published 1938. [https://books.google.com/books?id=KQY7AQAAIAAJ] (Japanese: 米国の旅日本の旅) Search terms: *"press in japan" *"japanese press" *"press of japan" *"journalism of japan" *"journalism in japan" *"journalists in japan" *"japanese journalism" Generations *[https://www.vox.com/2018/8/15/17686668/millennials-explained Stop calling teenagers millennials]. Vox. 15 August 2018. Planet Earth *[[w:Encyclopedia of Earth|Encyclopedia of Earth]] Crime *The Concise Encyclopedia of Crime and Criminals [https://books.google.co.uk/books?id=uGTQAAAAIAAJ] Showa era *懐かしの昭和・平成流行事典: 2001-1945. [[w:ja:新人物往来社|Shin-Jinbutsuoraisha]]. 2002. [https://books.google.co.uk/books?id=QCYyAQAAIAAJ] *少年ブーム～昭和レトロの流行もの. 串間努著. 2003. [https://books.google.co.uk/books?id=sK0nAQAAIAAJ] Fading of the Showa era *[https://www.theguardian.com/world/gallery/2025/dec/02/fading-japan-showa-era-in-pictures The fading of Japan’s Shōwa era – in pictures]. The Guardian. 2 December 2025. *[https://soranews24.com/2026/04/02/fading-tokyo-searching-for-signs-of-the-showa-era-as-local-neighborhoods-evolvephotos/ Fading Tokyo – Searching for signs of the Showa era as local neighborhoods evolve]. SoraNews24. 2 April 2026. Showa retro packaging *[[w:ja:初見健一|Kenichi Hatsumi]]. 昭和のレトロパッケージ. [[w:ja:グラフィック社|Graphic-sha]]. 2016. ISBN 9784766128741. [https://books.google.co.uk/books?id=Ch5wjwEACAAJ] Shotengai *[https://www.theguardian.com/world/2025/jul/18/cult-of-convenience-how-tokyos-retro-shotengai-arcades-are-falling-victim-to-gentrification ‘Cult of convenience’: how Tokyo’s retro shotengai arcades are falling victim to gentrification]. The Guardian. 18 July 2025. Shakespeare *Demmon (compiler). Catalogue of the Shakespearian Books and Pamphlets in the Joseph Crosby Library. 1885. [https://books.google.co.uk/books?id=GSZLAQAAMAAJ&pg=PA1#v=onepage&q&f=false]. *Shakespeare the Man and the Book. Part 2: Occasional Papers. 1881. [https://books.google.co.uk/books?id=gfUUAAAAYAAJ&pg=PP11#v=onepage&q&f=false] *Best films: [https://www.empireonline.com/movies/features/best-movies-of-all-time-us/] Survivability of past atmosphere *[https://news.climate.columbia.edu/2022/09/20/you-asked-dinosaurs-survived-when-co2-was-extremely-high-why-cant-humans/ You Asked: Dinosaurs Survived When CO2 Was Extremely High. Why Can’t Humans?] Columbia Climate School. 20 September 2022. *[https://www.sciencefocus.com/planet-earth/how-far-back-in-time-would-we-be-able-to-go-and-still-breathe-our-planets-air How far back in time would we be able to go and still breathe our planet's air?] BBC Science Focus. *[https://gizmodo.com/the-one-basic-fact-about-history-that-time-travelers-al-1652649190 The One Basic Fact About History That Time Travelers Always Forget]. io9. Gizmodo. 31 October 2014. Philology *W Pökel. Philologisches Schriftsteller-Lexikon. 1882. [https://books.google.co.uk/books?id=2jAaAAAAMAAJ&pg=PR1#v=onepage&q&f=false] *Rivista di filologia e di istruzione classica [https://books.google.co.uk/books?id=M6AzAQAAMAAJ&pg=PP5#v=onepage&q&f=false] [[User:James500|James500]] ([[User talk:James500|discuss]] • [[Special:Contributions/James500|contribs]]) 10:55, 26 October 2020 (UTC) hnp4rbrn70t6hi8n0e9v5bcwsq68my3 102 205987 2844880 2839880 2026-11-08T16:58:59Z ~2026-59313-65 3114017 2844880 wikitext text/x-wiki <!-- Add your name to the list using * ~~~~ --> * -[[User:Atcovi|Atcovi]] [[User talk:Atcovi|(Talk]] - [[Special:Contributions/Atcovi|Contribs)]] 13:19, 19 November 2016 (UTC) * Since 8 September 2011‎ with [[Dominant group/Astronomy]]. --[[User:Marshallsumter|Marshallsumter]] ([[User talk:Marshallsumter|discuss]] • [[Special:Contributions/Marshallsumter|contribs]]) 02:39, 27 April 2018 (UTC) *Likith raja singh {{unsigned|Likithrajasingh|21 January 2019‎}} *Palenie[[User:Pelanie For Life|Pelanie For Life]] ([[User talk:Pelanie For Life|discuss]] • [[Special:Contributions/Pelanie For Life|contribs]]) 08:51, 4 November 2020 (UTC) * Evaristo Mateyo - 29 June 2022, my username is [[w:User:Webwritter-junior|Webwritter-junior]]. * BrownieBytes, 06/08/2024 * [[SamLaxarox]]; Since October 12th, 2026. * Yasir Naeem Khan; Since November 7th, 2026. h6w8d81ta8sgq9t18tzn9lp7bh6p7d0 0 206753 2844888 2763539 2026-11-08T17:37:13Z ~2026-59366-51 3114020 Added missing "have" 2844888 wikitext text/x-wiki Most of this information comes from the masterminds of:<br> Werner Vycichl<br> Jozef Vergote<br> Sir A.H. Gardiner<br> Pierre Lacau<br> Antonio Loprieno<br> Gábor TAKÁCS<br> Helmut Satzinger<br> James P. Allen<br> Carsten Peust<br> Any contributing scholars not mentioned above will be added in future edits. Thank you for your hard work.<br> == Consonants == === f, p and b === * ''f'' is, as in English, a [[w:Voiceless labiodental fricative|voiceless labiodental fricative (f)]].<br> * ''p'' is a [[w:Voiceless bilabial stop|voiceless bilabial stop (p)]] and, under some conditions, aspirated (pʰ).<br> * ''b'' is a [[w:Voiced bilabial stop|voiced bilabial stop (b)]]. From the Late Kingdom onwards (and perhaps even earlier) ''b'' may have been pronounced as a [[w:Voiced bilabial fricative|voiced bilabial fricative (β)]] in some environments.<br> * ''b'' tends to be regarded as the ''unaspirated voiced'' counterpart of ''p'' (which is regarded as ''aspiratable voiceless'') - this is evident in Coptic variant spellings of these two phonemes, especially in syllable-final position.<br> === m and n === * These are pronounced as in English: [[w:Bilabial nasal|bilabial nasal (m)]] and [[w:Dental, alveolar and postalveolar nasals|alveolar nasal (n)]].<br> * It also appears that a vowel preceding ''m'' or ''n'' was strongly nasalized, culminating in ''n'' => [[w:Velar nasal|velar nasal (ŋ) in ''si<u>ng</u>'']] or possibly [[w:Uvular nasal|uvular nasal (ɴ)]] at the end of a syllable when followed by specific consonants (like g, k, etc.); in other instances ''m'' and ''n'' may have had a geminated (prolonged) enunciation.<br> * Original < n > develops into < m > when preceding labials < p, m > and sometimes < b > '''but''' not < f ><ref>Carsten Pesut pg 161.</ref>. There are also indications that < q > could provoke an assimilation n > m at a Pre-Coptic stage. While < n > frequently assimilates to a following labial, m is normally unaffected in its place of articulation by a following consonant, except in a few Coptic words.<br> ::: Note: This assimilation is not regular across a morpheme boundary. However, the final -Ⲛ^{^Copt} of some proclitic elements may develop into -Ⲙ^{^Copt} before a labial. Assimilation is common (obligatory at least in Sahidic)<ref>Carsten Peust pg 161.</ref>.<br> * Another point to bear in mind is that Coptic neutralised the difference between /o/ and /u/ adjacent to /m/ and /n/. Therefore, besides disliking /o/ in unstressed syllables, Egyptian also replaced it with /u/ in certain phonemic environments. For instance, if /o:/ (Ⲱ <ō>) forms a syllable with preceding (non-syllabic) /m, n/, it is according to Layton “always manifested as /u/ (OⲨ <ou>)” and otherwise as /o:/ (Ⲱ <ō>). Layton (2000: 21) gives a paradigm example of the possessive prefix formation in single masculine, single feminine, and plural:<br> : ⲠⲰ= <pō> /po/ : ⲦⲰ= <tō> /to/ : ⲚOⲨ= <nou> /nu/ Hence, /u/ is an allophone of /o:/ in Coptic.<br> :: The change from the standard vowel /o/ to /u/ takes place precisely after /n/. However, the Coptic phenomenon of reducing /o/ to /u/ adjacent to /m, n/ serves as a perfect example alongside other Egyptian-influenced variation in Greek. It is not regular. It sometimes shows in nonstandard spellings of Greek /o/ but it does not completely apply to Egyptian-influenced spelling of Greek, nor to the nonstandard usage of Greek loanwords in Coptic. Both have /o, u/ confusion that seems allophonic and is undoubtedly influenced by Egyptian, but not only after /m, n/<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 94</ref>.<br> :: Coarticulation is a regular feature in the nonstandard spellings of Egyptian scribes. Even in the examples provided by Girgis (1966, 81-82), /o/ is replaced with /u/ not only after /m, n/, but seemingly according to the consonantal environment. The tendency seems to point toward favouring /u/ with phonemes that might raise the vowel quality from /o/ to /u/, i.e. bilabials, dentals and liquids; one exception is replacing /o/ with /a/ (adjacent to liquids and bilabials) if it appears in a pre-stressed syllable, and with /u/ or /e/ if post-stressed. The sample so far is small, though, so more research is required to resolve the matter<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 129</ref>.<br> === The Four H's: h, ḥ, ḫ, <u>h</u><ref>This article gives more insight on some of these sounds: http://homepage.univie.ac.at/helmut.satzinger/Texte/scratchy.pdf</ref> === * ''h'' is a [[wikipedia:Voiceless glottal fricative|voiceless glottal fricative]] as it is in English <u>h</u>ello.<br> * ''ḥ'' started out as an [[w:Voiceless pharyngeal fricative|voiceless pharyngeal fricative (ħ)]]. Typically characterized as a fricative in the upper pharynx, it is often a whispered [h]. The two consonants ''h'' and ''ḥ'' merged into Coptic ''h''.<br> * ''ḫ'' is thought to have been a [[w:Voiceless velar fricative|voiceless velar fricative (x)]], with a ''possible'' eventual merge into a [[w:Voiceless uvular fricative|voiceless uvular fricative (ꭓ)]] or a [[w:Voiced velar fricative|voiced velar fricative (ɣ)]], especially in colloquial/popular speech.<br> :: Egyptian < ḫ > frequently substitutes Semitic /x/ in New Kingdom loans. :: Occasionally (irregularly) used in lieu of a [[w:Voiced pharyngeal fricative|voiced pharyngeal fricative (ʕ)]] from Semitic loan words<ref>http://real.mtak.hu/28225/1/QUESTIONS%20OF%20EGYPTIAN%20HISTORICAL%20PHONOLOGY%20AND%20AFRO-ASIATIC.pdf (QUESTIONS OF EGYPTIAN HISTORICAL PHONOLOGY AND AFRO-ASIATIC by Gábor TAKÁCS) pg 7.</ref>. :: This sound has two (Pre-)Coptic descendants: ''ḫ'' and the palatalized ''<u>h</u>''. This occurred in the New Kingdom, with ''ḫj'' (h̭) occasionally used for older ḫ where the Coptic descendant is ''<u>h</u>'' . This new digraph in the New Kingdom indicates a secondary palatalization (x > <u>x</u>).<br> * ''<u>h</u>'' has an interesting history. In the earliest time there was no phoneme corresponding to /<u>h</u>/. The sound /x/ corresponding to < š > was frequently palatalized to /sh/ in the Old Kingdom. One of the most widely accepted hypotheses for this sound is that the grapheme < š >, which formerly had represented a back fricative, thus became primarily a means of writing a palatal fricative. In the minority of words in which /x/ escaped palatalization, the preserved back fricative now had to be expressed by a different sign; for this purpose /<u>h</u>/ was invented <ref>Carsten Peust pg 116.</ref>.<br> :: It appears that most scholars believe this sound (agreed upon that it was an < h > of some sort) was a [[w:Voiceless palatal fricative|voiceless palatal fricative (ç)]], articulated with a hint of palatalization, especially from the Middle Kingdom onward. Other scholars claim this sound was initially a voiceless counterpart of < ḫ >, so that < ḫ > would have needed to be voiced - according to this scheme (and excluding the hypothesis of the split ḫ ~ <u>h</u>), ḫ was palatalized to < š > under certain environments.<br> :: The conditions for the palatalization of ''š > /x/'' are not known. There is perhaps a connection to the palatalization of "back stops" discussed below in the section ''Palatalization'' under ''Palatalization caused by labials in the Old Kingdom''<ref>Carsten Peust pg 116.</ref>.<br> === š === * [[w:Voiceless palato-alveolar sibilant|voiceless palato-alveolar sibilant (ʃ)]]. The consonants transcribed as ''<u>h</u>'' and ''š'' are regularly distinguished only after the Old Kingdom. Words with later ''<u>h</u>'' were at first regularly spelled ''š'' (but not vice versa).<br> === s === * This was a [[w:Voiceless alveolar fricative|voiceless alveolar fricative (s)]], although originally there may have been a supplementary feature |+palatal| yielding an articulation close to ''sʲ'' - similar to the cluster [sj] occurring in English ''miss you''.<br> * In Ancient Egyptian, the sign 𓊃 (s=z) is said to represent a sound much like Arabic ز /z/ (though possibly, voiceless) and (ś) is said to represent 'unvoiced s', (presumably /s/ with post-aspiration). : There is some uncertainty about the values of these two signs. Worrell comments: "It would be strange if any language were without a plain s-sound and a plain z-sound, particularly Egyptian, since the Semitic languages all have a plain s and z." The Egyptian sign s is probably etymologically equivalent to [[wikipedia:Voiced dental fricative|old Semitic z (a voiced dental fricative ð)]] and is confused in Egyptian writing with <u>d</u> (𓆓; Ϫ partly derives from <u>d</u>), also a voiced sound, though it appears in all dialects of Coptic as voiceless s. The ś is not related to any voiced sound, nor ever confused with any. In order, then, to provide Egyptian with a plain s-sound and z-sound, it is necessary to suppose that the Egyptian sign s really represented z, and that the sign ś represented s; and that z (from z and ð) lost its voicing from the Middle Kingdom onward, and thus became plain s. That would explain why both Egyptian ś and s appear in all dialects of Coptic as Ⲥ.<br> : To be sure, there is no reason why this fricative should lose its voicing in Egyptian: there is no general movement in Egyptian phonological history that would account for it. Nevertheless the unvoicing must have occurred, for Coptic has no z.<ref>https://copticsounds.files.wordpress.com/2012/10/ishak-emile-maher-the-phonetics-and-phonology-of-the-bohairic-dialect-of-coptice280a6-d-phil-thesis-university-of-oxford-1975-volume-2.pdf ... pg 668</ref><br> : Professor Johnstone comments: "Worrell here however makes difficulties for himself.. Ancient Egyptian is quite likely to have started with a series of voiceless unaspirated and aspirated consonants, as with a series of voiced and voiceless consonants ... By this criterion, /z̥/ (s) and sʰ would be a part of this series:<br> : {| class="wikitable" |- ! voiceless<br>unaspirated !! aspirated<br>consonant |- | b̥ || pʰ |- | d̥ || tʰ |- | ( z̥ ) || ( sʰ ) |} : Moreover, the z̥ / sʰ opposition fits well with the facts in Coptic ..." (Johnstone) * Worrell, in his comment on the Zeniya tradition, says, "The [Coptic] letter C is called sámma (Stern, sima, same; Steindorff, sīma), and is pronounced /s/ in all but a very few cases "It is palatalized to š, without any reason other than the presence of a front vowel in one word ⲤⲈ <ši> - yes ..." This is also noted and explained by Antonio Loprieno<ref>https://copticsounds.files.wordpress.com/2010/02/egyptian-phonology.pdf .. pg 5</ref>. === z === * Old Egyptian |s| is the heir of the Afroasiatic [[w:Voiceless dental fricative|voiceless dental fricative (θ)]] and [[w:Voiceless alveolar sibilant| voiceless alveolar sibilant (s)]] and thus may have represented either sound. Other theories state that it may have been a [[w:Voiceless alveolar affricate|voiceless alveolar affricate (t͡s)]].<br> * May have also been a sort of [[w:Ejective consonant|ejective (sˈ)]] * At some point before the Middle Kingdom, |z| and |s| were neutralized.<br> === k, q and g === * ''k'' is a [[w:Voiceless velar stop|voiceless velar stop (k)]]. Possibly aspirated (kʰ) and/or palatalized (kʲ) under certain environments.<br> * ''q'' started out as a [[w:Voiceless uvular stop|voiceless uvular stop/plosive (q)]], pronounced like ''k'' except that the tongue makes contact not with the soft palate but with the uvula. Eventually it was pronounced like a [[w:Uvular ejective|uvular ejective (qʼ)]] .<br> * ''g'' is a [[w:Velar ejective|velar ejective (kʼ)]].<br> === d and t<ref>''t'' colloquially was not pronounced when ending a syllable, for ex: nāf(i)rat => nāfra, nāfrə or nāfre.... Note: ''stressed -a'' ~ ''u'' did not occur until the Late Kingdom when ''stressed -a'' ~ ''o''.</ref> === * ''d'' may have been:<br> :: an [[w:Ejective consonant|ejective]] [[w:Apical consonant|apical consonant]] t̺ˈ, or :: an ''apical non-ejective d̺'' (see the section Glides below) <br> : Other hypotheses:<br> :: a [[w:Voiced dental and alveolar stops|laminal denti-alveolar (d̪)]] similar to Spanish, or :: like the emphatic/pharyngeal ''dˤ'' of Arabic<br> : Its ''actual'' pronunciation is a matter of debate but it may have been similar to an ''ejective apical t̺ˈ'' or ''apical non-ejective d̺ -'' indirect evidence is provided by ejective/aspirated alternations within some consonants, and by the Coptic change from orthographic ''d'' to ''t''. Its disappearance in Coptic does not resolve the issue.<br> * If we assume ''d ~ t̺ˈ'', then ''t'' may have been ''t̺(ʰ)'', the non-ejective aspiratable counterpart of ''d''.<br> === <u>d</u> and <u>t</u> === * ''<u>d</u>'' was the palatal(ized) counterpart of ''d''. Possible realizations include[[w:Palatalization (sound change)| ''t̺ʲˈ'']], a [[w:Palatal ejective|palatal ejective (cʼ)]], a [[wikipedia:Palato-alveolar ejective affricate|palato-alveolar ejective affricative (t͡ʃʼ)]], t̺ˈʃ / tˈʃ, a [[w:Voiced palato-alveolar affricate|voiced palato-alveolar affricative (d͡ʒ)]], (possibly) an [[w:Ejective consonant|ejective post-alveolar voiced affricate (dʒʼ)]], a [[w:Voiced palatal stop|voiced palatal stop (ɟ) ~ ejective (ɟˈ)]], or a [[w:Voiced palatal affricate|voiced palatal affricate (ɟ͡ʝ)]]. This digraph may have originally split into several different sounds with similar pronunciations and, by the time of Coptic, shows a gradual merging into ɟ with total loss of the ejective characteristic. <br> * Ϫ represents <u>d</u> in Coptic (and is always compared to Classical Arabic reflex ǧīm ج */ɟ/). This sound appears to have some peculiarities: it starts off in Northern Egypt (and Cairo) as<br> :: a [[w:Voiced velar stop|voiced velar stop (g)]] as in English ''gaggle'', typically before the vowels / a, u, o /; or :: a [[w:Voiced palato-alveolar sibilant|voiced palato-alveolar sibilant (ʒ / ž)]] sometimes before the vowels / e, i / ; a few rural speakers away from Cairo pronounce [ʒ] instead of [ɡ]<br> : An interesting feature shown here is still questioned:<br> ::: I too still presume that /j/ might have shifted into /g/ (in Egypt). Nonetheless Wadi Hanifa pointed out some historical notes suggesting that no changes have occurred, but instead Egyptian Arab speakers have retained an originally Yemenite pronunciation of /j/, which some claim to be /g/. However no body has provided any archaeologically authentic evidence for these indications so far. I wonder: how come no reliable scholar has ever taken this issue, in a scientific manner, into account?<ref>https://forum.wordreference.com/threads/egyptian-yemeni-arabic-%D8%AC-%D8%AC%D9%8A%D9%85-pronounced-as-hard-g.264201/</ref> An article here goes into further detail<ref>https://www.researchgate.net/publication/254917451_The_gg-question_in_Egyptian_Arabic_revisited</ref>. : This means that a native palatalization feature (stemming from Ancient Egyptian palatalization) emerged against an Arabicized /g/ in an area where ancient Egyptian was once spoken, thus indirectly influencing the sound change. Further south in modern-day Egypt, the palatalization is distinctive in all Egyptian dialects:<br> :: Asyut - [[w:Voiced palatal stop|palatalized voiced velar stop / voiced post-palatal stop (ɡʲ)]]<br> :: Luxor - [[w:Voiced palatal stop|palatalized voiced dental / alveolar stop (dʲ)]], regarded as an ''affricate'' - ğ / dj<br> :: Aswan - d͡sʲ , an extremely unusual sound of which I have not been able to find any examples<br> :: Western Delta - [[w:Voiced alveolar fricative|voiced alveolar fricative (z)]] :: In A<u>h</u>mīm and Girgah (in Upper Egypt), the sound /d/ often stands for /g/. The people there say 'Dordy' for Giorgy, and 'Damian' for Gamian, and 'Dirdisi' for Girgiso. This however does not mean that they cannot pronounce the letter /g/; but to some people it is sometimes very difficult to pronounce the hard /g/. Their priests often say 'Dawardios' for Gawargios<ref>https://copticsounds.files.wordpress.com/2012/10/ishak-emile-maher-the-phonetics-and-phonology-of-the-bohairic-dialect-of-coptice280a6-d-phil-thesis-university-of-oxford-1975-volume-2.pdf ... pg 649</ref> In Minya and Asyūṭ (Upper Egypt); on the other hand, /d/ is sometimes pronounced /ɟ/. Also, Worrell notes: "In Luxor, Arabic ɟ > d before š: dēš for ɟēš and daḥs for ɟaḥš ..."<br> : Thus the word ''camel'' (جمل - ɟamal^{^{Standard Arabic}}) is pronounced gěměl, ɡʲěměl, dʲěměl, and d͡sʲěměl, respectively.<ref>https://www.jstor.org/stable/pdf/592389.pdf?refreqid=excelsior%3A557ec7937c70b5dc59d6a692b129eb83</ref> * ''<u>t</u>'' is considered the palatal(ized) counterpart of ''t'' : either [[w:Palatalization (sound change)| ''t̺ʲ'']], a [[w:Voiceless palatal stop|voiceless palatal stop (c)]] or a [[w:Voiceless palato-alveolar affricate|voiceless palato-alveolar (t͡ʃ)]]. Historically, <u>t</u> originated from palatalized /kʲ/ or other Semitic sounds foreign to Egyptian, but was eventually, in a majority of cases, de-palatalized to /t/. * Ϭ ( <u>t</u> ) in Coptic appears to be a particularly uncertain and ambiguous letter but vocalized mostly as a generalized /š/. Another popular pronunciation is the unusual combination /gš/ or /ɟš/ specifically in the Bohairic Dialect spoken in and around Cairo. Ϭ is generally believed to have been some kind of /tch/ sound or even /k/, but seems to have been a rather unpopular sound, vanishing and being replaced by other similar sounds. === r and l === * ''r'' is a [[w:Flap consonant|central alveolar flap (ɾ)]], almost identical to Italian or Spanish ''r'' or the ''dd'' in American English ''la<u>dd</u>er''.<br> * Although Egyptian did not have a letter < l > until the New Kingdom / Late Egyptian, the [[w:Dental, alveolar and postalveolar lateral approximants|lateral approximant (l)]] did exist and may have sounded something like the Japanese [[w:Dental, alveolar and postalveolar lateral flaps|alveolar lateral flap (ɺ)]]<ref>Merely a hypothesis based upon Coptic Fayyumic, in which case would be better regarded as a dialectal variation of |r| ''possibly'' of < l > in the main Sahidic or Bohairic dialects. </ref>, or (less likely) a [[w:Retroflex flap|retroflex flap (ɽ)]]<ref>Merely a hypothesis based upon Coptic Fayyumic, in which case would be better regarded as a dialectal variation of Coptic orthographic |r and l|. </ref>.<br> * The Ⲗ ~ Ⲣ replacement is a well-known Fayyūmic peculiarity, but it is by no means confined to Fayyūmic.<br> *Worrell comments on the AE /r-l/ sound: "Egyptian ꜥrj must have been pronounced with an /l/, because that word has an /l/ in the Semitic languages as well as in Coptic; ⲀⲖⲈ. There would seem to be no doubt that New Egyptian has an /l/. The Canaanitish /l/ was correctly heard; and was represented, like their own /l/, by the /n-/ sign or the /r-/ sign, or by a combination of the two"<ref>https://copticsounds.files.wordpress.com/2012/10/ishak-emile-maher-the-phonetics-and-phonology-of-the-bohairic-dialect-of-coptice280a6-d-phil-thesis-university-of-oxford-1975-volume-2.pdf ... pg 663</ref>.<br> :: He adds: "It is true that the Fayyumic dialects (with more or less consistency) have an Ⲗ where all the other dialects have Ⲣ. But the other dialects have both Ⲣ and Ⲗ, and it is more likely that /r/ and /l/ have fallen together in Fayyumic, than that they have been differentiated in the other dialects. At the same time, it is possible that Egyptian writing lay under the influence of people who pronounced the /r/ in such a way as to remind one, of /n/ on the one hand, or of /l/ on the other. The sound /r/ has many possible transformations and must have been pronounced differently in Egypt at different times and places"<ref>This ''< r ~ l >'' phenominon exists in several languages, for example in the Spanish dialect of Puerto Rico:<br> Note: Taking into account that it is believed Spanish < r > and Egyptian < r > are articulated identical only showing that a lateral tap < r > can sound like an < l > with no known genetic relationship between the two languages.<br>'''Lateralization of /r/ to [l]'''<br> The /r/ that comes at the end of a syllable (not followed by a vowel) is often changed to an /l/, so that words like "perdón" (forgiveness) and "Puerto Rico" become "peldón" and "Puelto Rico" respectively.<br></ref>.<br> :: It could be deduced from this evidence that /r/ raises the quality of /o/ in the same way as does nasalization<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ... pg 95</ref>. Peust (1999: 240-243), however, suggests that vowel raising only appeared in front of /r/ in Semitic loanwords due to an originally velarised quality of Semitic liquids, still present in some of the more archaic vocabulary such as ''allah''. :: Often, /r/ lowers the quality of a preceding close vowel: < Ⲓ > /i/, < ⲈⲒ > /(e)i/, < Ⲏ(Ⲓ)> /ē(i)/ are often replaced with < Ⲉ > /ɛ/, and < Ⲉ >, < ⲀⲒ > /e/ are replaced with <a><ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ... pg 98</ref>. Hence Coptic /r/ seems to retract a preceding vowel's quality, although /r/ generally seems to centralise vowels. === Glides & Weak Consonants === '''ꜥ'''<br> * The Egyptian orthography < ꜥ > may have originally been a:<br> :: ejective apical consonant /t̺ˈ/ -- then eventually evolving into a glottal stop < ʔ > - currently the most popular theory<br> :: voiced dental apical non-ejective /d̺/ - this phonological change is termed the ''Rösslerian view'', named after the scholar who first theorized it. <ref>This is currently one of the most widespread hypotheses. This is also a sound that is lacking from the Egyptian orthographic inventory and alphabet. The non-existance of this sound in Egyptian tends to be considered highly unusual to experts.</ref> -- then eventually evolving into a glottal stop < ʔ > in the progressive dialect. <br> :: emphatic/pharyngeal /tˤ, dˤ/ -- then evolving into a pharyngeal < ˤ , ʕ > <br> The ''merging'' was achieved by the time of Middle Kingdom thus losing its consonant nature<ref>The general belief of this theory is if /d/, /<u>d</u>/ and /<u>t</u>/ were pharyngeal(ized) the original consonant was /d/, /<u>d</u>/ or /<u>t</u>/ possibly emphatic /t/. It appears a dialect (or a variety of different dialects) played a crucial role in the dubious usage of this letter in the Old Kingdom as can be seen in comparison within the hieroglyphs. The same can be said if /t/ was ejective, eventually being assimilated into a glottal stop by the Middle Kingdom.</ref>.<ref>In the lexicon of the OK, Egn. < ꜥ > is incompatible with dentals/alveolars, in particular with < d > and < z >. There are no roots with ꜥd(...), ꜥCd, dꜥ(...), dCꜥ, Cꜥd, Cdꜥ; ꜥz(...), ꜥCz, zꜥ(...), zCꜥ, *Cꜥz, *Czꜥ. This proves that < ꜥ > it was – originally – a dental/alveolar itself....<br>It is compatible with laryngeals ( ḫ, ḥ, <u>h</u>, š [< <u>h</u>]) and with all velars/palatals except k / <u>t</u>, hence g, q, <u>d</u> [< ḳ]. This proves that Egn. < ˁ > was – originally – not a laryngeal itself... http://homepage.univie.ac.at/helmut.satzinger/Texte/VoicedStops.pdf pg 7.</ref><br> * After < ꜥ > adopts the pharyngeal sound value < ˁ > or glottal stop < ʔ >, there is a tendency for it to undergo dissimilation to < j > in the neighborhood of < ḥ ><ref>Carsten Peust pg 103.</ref>:<br> :: ꜥḥ ~ jḥ^{^MEg} - palace.<br> :: mḥꜥw ~ mḥjw^{^MEg} - flax<br> * When < ꜥ > adopted the value < ˁ > or < ʔ > at about the time of the Middle Kingdom, it could be dissimulated to < j > in the neighborhood of < ḫ > (perhaps <u>h</u>), as it was in the neighborhood of < ḥ ><ref>Carsten Peust pg 104.</ref>. * This phoneme ''was'' generally believed to be ''The Egyptian Ayin'' a [[w:Voiced pharyngeal fricative|voiced pharyngeal fricative (ʕ)]], possibly a [[Voiced pharyngeal fricative | voiced epiglottal (pharyngeal) central approximate (ʕ̞)]], but this theory has slowly been disregarded by a majority of scholars.<br> * Egyptian < ꜥ > was occasionally devoiced to /ħ/ and then retained in Coptic as Ϩ. This development is found primarily in Bohairic, but is by no means regular<ref>Peust pg 105.</ref> '''Ꜣ'''<br> * In earlier Egyptian ''may'' have represented a [[w:Uvular trill|uvular trill (ʀ)]], [[w:Voiced uvular fricative|voiced uvular fricative (ʁ)]] or anything of the like<ref>In my opinion, < Ꜣ > can thus primarily be regarded as some kind of guttural ''r'' sound which fell away in pronunciation at an early time period. It appeared that as the language progressed there was a gradual reduction of guttural sounds.</ref><br> * Some other theories, which are less likely (or ''may'' be dialectal variations), are that < ɜ > may have started out in Old Egyptian as a type of [[w:Lateral consonant|lateral approximate (l, ɫ, ect..)]], a [[w:Voiceless dental and alveolar lateral fricatives | voiceless dental and alveolar lateral fricative (ɬ)]], an [[w:Dental, alveolar and postalveolar lateral approximants | alveolar lateral approximant ⟨l⟩]] or even the more extreme hypothesis that it was an [[w: Alveolar and postalveolar approximant | alveolar/postalveolar approximant < ɹ >]].<br> * In general, it appears < Ꜣ > was eventually used as a written allophone orthography representing (''in lieu '' of) prior sounds that were no longer ''fully vocalized'' under specific environments (according to the consonant's complete orthographic disappearance in Coptic)- very similar to the Egyptian < j >. This was achieved at a time when < Ꜣ > lost it's authentic articulation but the consonant continued to be used erratically. In affect, this has caused a great deal of confusion as to it's original sound.<br> * By the Middle Kingdom, < ɜ > turned into a [[w:Glottal stop|glottal stop (ʔ)]]- which is similar to the ''gulping/choking'' sound found in the British pronunciation of ''bo<u>tt</u>le''.<br> * Was originally regarded as ''The Egyptian Aleph'' < ا , ʔ ''The Glottal Stop''> '''but''' the glottal stop enunciation of this phoneme appeared to exist as a secondary feature during the Middle Kingdom and because of this experts have come up with new hypotheses. '''j'''<br> * Since prehistoric times |j| is believed to have represented a [[w:Semivowel|palatal approximate (j, ʲ)]].<br> * By the beginning of the Middle Kingdom |j| assimilated into a [[w:Glottal stop|glottal stop (ʔ, ^{<small>ʔ</small>})]] before an unstressed vowel in initial position (jawīn > ^{<small>ʔ</small>}awīn), as well as at the end of a syllable of a stressed syllable (bājnat > bā^{<small>ʔ</small>}nat).<br> * Roots with medial <j> / <ɜ> eventually conform to a ''hollow'' root in Coptic. In the older language there may have been other rules applied determining when to simplify the pronunciation/spelling, until now, there is not enough research but it can be thus assumed, when a root was used as a verb, medial <j> / <ɜ> was most likely omitted (or modified) because of constant fluctuations due to the additions of suffixes ''and'' nouns (or any verbal form being used as a noun) used the full pronunciation. For more examples and explanations, I have dedicated a page to the ''hollow'' verb [[Pre-Late Egyptian Reconstruction/The Egyptian Hollow Verb| here]].<ref>Carsten Peist pg 148, states: ... It was discussed in § 3.13.3 that in the succession stressed vowel - <w> - consonant, <w> was usually written <y> from the 1st Intermediate Period on. This explains why <w> in this position is not usually preserved in Coptic. But <j>, including <j> <Ꜣ>, is not preserved in Coptic either. So the general rule is that by the time of Coptic all glides were lost when directly following the stressed vowel and preceding a consonant. It is difficult to say whether the loss of all glides was contemporaneous or not. Some examples:<br> wꜢḥ - to put ~ OⲨⲰϨ^{^S.}, OⲨOϨ^{^B.}<br> bjn - bad ~ ⲂⲰⲰⲚ^{^S.}, ⲂⲰⲚ^{^B.}<br> fꜢ.t - to carry ~ ϤⲒ^{^S.B.}</ref><br> '''y'''<br> * Either represents ''y'' in ''<u>y</u>es'' or can be used in lieu of ''j''. It appears to have been originally used for Afroasiatic ''y'' in loan words or group writing but also took on the unstable characteristics of Egyptian < j >.<br> * There are also indications where < y > may have indicated, or at the least included, an indiscriminate vowel (possibly i, e or a).<br> * < y > may have been the ancestor, or at the least the inspiration, of the Late Egyptian/Demotic letter < e >. <br> '''w'''<br> * Is like it is in English [[w:Labio-velar approximant|labio-velar approximant (w)]].<br> * Like Egyptian ''-j'', w may have signaled a vowel rather than -Vw / -wV ''especially'' when used as a suffix/clitic/addition.<br> * The diphthong -aw may have sounded like äʊ or äʊ̯ which is a popular pronunciation used in many Afroasiatic languages.<br> ==== Elimination of Weak Consonants ==== * /t, r, j, w, ꜥ and Ꜣ/ are deemed The '''Weak''' Consonants and usually will fall away at the end of an unstressed syllable<ref>Or in other positions sometimes in an unpredictable fashion</ref>:<br> :::: na<u>t</u>ǎrat ~ na<u>t</u>ǎra^{<small>ʔ</small>}<br> * /t, r, ꜥ and Ꜣ/ can additionally also fall away even in stressed position:<br> :::: jātraw ~ jā^{<small>ʔ</small>}raw <br> * /w/ is the most stable of the weak consonants appearing in most positions; that is if it was used as a consonant, there are instances, where, instead, /w/ indicated the presence of a vowel explaining its disappearance in Coptic (i.e., the participle forms and stative). <br> * Sometimes other consonants such as /<u>d</u>, <u>t</u>/ (especially when assimilated to /t/ in later phases of the language), /m/, /n/, /l/ & ''periodically'' /b, p, k, ect.../ can all fall away in an inconsistent manner. <br> * These phonological processes are not always indicated in the hieroglyphics (when they were most likely pronounced) but is majorly used in Coptic and to a lesser degree in Demotic.<br> ===== As Matres Lectionis ===== In more recent developments, /ꜥ, Ꜣ, w, j, y/ may have signaled a vowel + semi-consonant syllable especially in combination with other glides, i.e., Ꜣj, jj, ꜥꜢ, ect. In this type of scenario the syllable structure changes in 3-rad words consisting of a medial /Ꜣ/ - bꜢk ... ultimately in these type of words we were probably dealing with eventual reduction: baꜢ^ək ~ baaꜢk (a combined guttural long 'aaa' sound which quickly turned into an /oooo/ vowel); words like ''baaꜢk'' were spelled either with medial /Ꜣ/ or /0/ in the hieroglyphics... and sometimes in lieu of /Ꜣ/ we have /j ~ i/ especially at the end of a word. Medial /w & j/ had a tendency to completely vanish in speech or pronounced in a very light fashion which is possibly why in the hieroglyphs there can be found various spellings with and without /w & j/. /ꜥ/ followed a similar pattern to /Ꜣ/, except that in most cases the vowel was short and not long and the /a/ vowel generally continued to be pronounced /a/. Because of these inconsistencies it can be rather difficult to learn new words by just reading the hieroglyphics because you would have to first recognize the word being used in order to tell how that word may have been pronounced especially if the original scribe spelled the word in a reduced fashion. ==== Extra Notes on Weak Consonants ==== In group writing transcriptions of Semitic words, it is interesting to note that the Semitic consonants: ʿ, ḫ, ḥ and ǵ (Arabic Ghain/Ghayn: ʁˤ / ɣ~ʁ/) (which is transcribed as g or q in Egyptian) are all transferable to the Egyptian renditions. The diphthongs ay and aw usually appear in their contracted forms and Ꜣ usually represents Semitic r~l. === Emphatic/Pharyngeal VS Ejective/Glottal === There is some debate as to whether ''q, g, d, z, <u>t</u>, and <u>d</u>'' were [[w:Emphatic consonant|emphatic]], [[w:Pharyngealization|pharyngeal]], [[w:Glottalization|glottal]] or [[w:Ejective consonant|ejective]]. <br> Emphatic groupings (a fancy way of implying ''pharyngeal'' characteristics /tˤ/) tend to be the most accepted theory in the field with glottalized groupings (a fancy way of implying ''ejective'' features /tˀ/) not far behind. In Egyptological sources, both emphatic and glottalized consonants are not entirely defined and instead can imply a much more broad spectrum of phonological features. <br> I have chosen to lean towards an ''ejective'' grouping of consonants, mainly because other Egyptian consonants were ''ejective'' in nature which causes speculation as to other consonants were as well and that these series of consonants constituted an ''ejective grouping''- there is ''some'' indirect evidence in Bohairic orthography. Ejective consonants are also fairly prominent among other Northern African languages near to Egypt and extend down the Nile river into the Horn of Africa.<br> This diacritic /tʼ/, in IPA, can either represent Emphatic or Glottalized. == Palatalization == In Proto-Egyptian and Old Egyptian, under specific environments [[w:Velar consonant | velar consonants]] shifted to their [[w:Palatalization (sound change) | palatalized]] counterparts.<br> :: {| class="wikitable" |- ! Original !! Modified |- | k || <u>t</u> <ref>Carsten Peust pg 120.</ref> |- | g, q || <u>d</u> <ref>Carsten Peust pg 120.</ref> |- | ḫ and <u>h</u> || š |} In Pre-historic Egyptian, those roots which appear to be an Afroasiatic (better analyzed as a Semitic) [[w:Cognate | cognate]] which contained the vowel /i/ following the ''Afroasiatic'' consonant(s) /k, g/ sometimes /q/ (and some other consonants) shifted to their palatalized counterparts in Egyptian. It is also interesting to note, that this consonant + vowel combination constitutes one unit in Egyptian, in e., -ki^{^PAA} => <u>t</u>^{^Proro-Eg} then a vowel was added unrelated to this original unit, possibly a schwa, i.e., -a<u>t</u>ə<br> :: -ki (2nd fem sing pronoun - you) = -a<u>t</u>(ə)<br> Former /s/ (including /z/) frequently develops into a palatal sibilant < Ϣ > in Coptic by assimilation to another palatal in the word. The principal rules are the following<ref>Carsten Peust pg 168.</ref>:<br> * /s/ usually becomes Ϣ^{^Copt} if there is another Ϣ (< š) somewhere in the same word<ref>An unexplained exception is šꜢs "nomad" > ϢⲰⲤ "herdsman".</ref>:<br> :: zšn (possibly original zššn) - lotus ~ ϢⲰϢⲈⲚ<br> * A palatal sibilant Ϣ which is derived from ḫ causes assimilation in Bohairic only<ref>There is no assimilation in wsḫ "to be large ~ OⲨⲰϢⲤ^{^S.B.} (with metathesis)</ref>, OⲨⲰⲤⳈ^{^A.}:<br> :: ḫsf - to repulse ~ ⲤⲰϢϤ^{^S.} (with metathesis), ⳈⲰⲤϤ^{^A.}, ϢⲰϢϤ^{^B.}<br> * If an original palatal stop (i.e. Ϭ / Ϫ < <u>d</u>, <u>t</u>) follows somewhere in the same word, /s/ is assimilated, though not always in all dialects:<br> :: s<u>d</u>d - to talk ~ ϢⲀϪⲈ^{^S.}, ϢⲈϪⲈ^{^A.}, ⲤⲀϪⲈ^{^B.}<br> ::: If it precedes, there is no assimilation:<br> :::: <u>t</u>zj - ϪⲒⲤⲈ^{^S.A.}, ϬⲒⲤⲒ^{^B.}<br> * A palatal stop derived from g / k has an even less palatalizing effect. It can only affect < s > in direct contact:<br> :: sg - stupid ~ ⲤOϬ^{^S.}<br> * The palatalization of /s/ can occasionally already be observed in Demotic. In words of this type, palatal assimilation can be observed even earlier<ref>Carsten Peust pg 169.</ref>.<br> It is generally believed that Egyptian did not originally have palatalized consonants, but that they appeared under specific environments and continued to be used this way into Coptic sometimes with slight instabilities.<br> ==== Palatalization caused by labials in the Old Kingdom ==== * /k/ and /q/ are incompatible with /p/ and /w/ <ref>That is '''if''' /w/ was pronounced as a (semi-)consonant '''not''' if in the hierpglyphs /w/ represented a vowel.</ref> (and perhaps other [[w:Labial consonant | labials]], for example /b/ ) within an Egyptian root and also shifted to their palatal counterparts.<br> :: kbw - sandals ~ <u>t</u>bw<br> :: kw (normally <u>t</u>w) - dependent pronoun 2nd pers. sg. masc.<ref>It is better to analyze this as a feminine form collapsed and adopted as the masculine form rather than an assimilation due to contact with /w/.</ref> :: Ꜣ<u>t</u>p - to load, carry<br> :: wꜢ<u>d</u> - green, yellow<br> == Vowels == Numerous scholars of the 19th century to early 20th century, examining the Egyptian language in its infancy, ''hint'' at Egyptian, at its core, being a type of [[w:Mixed language|fusional hybrid language]], at the most extreme an enhanced [[w:Creole language|creolized language]]<ref>JOURNAL ARTICLE Egyptian: Creole Origin Theory Oceanic Linguistics Special Publications No. 14, A Bibliography of Pidgin and Creole Languages (1975), pp. 53-55</ref>. Whether this has to do with the concepts of other Afroasiatic languages being used to understand Egyptian to extract grammatical information, or Egyptian is, in fact a hybridized language, it is quite possible that Egyptian does not exclude nor entirely include the below mentioned theories but rather coalesces them thus culminating into the Egyptian language.<br> Vowels for Egyptian are fairly difficult to reconstruct since we don't have much insight on the manner of exact articulation. In studies throughout the field there appears to be three major ''theories'' in regard to the Egyptian vowels and how they were used:<br> * 1) the vowel was always a generalized /a ~ ^ə/ and due to the proximity of specific phonological and grammatical environments, as well as adaptations of foreign words /a ~ ^ə/ morphed into another vowel causing ''harmonious'' enunciation. We'll call this theory '''The a-Vowel Theory''' throughout this study. Representation of the vowels /i/ and /u/ were represented by phonemes if they were used.<br> ... ::: They (i.e., the Akkadians) did not realize the tremendous advantage of vowels, but rather thought of syllables as single sounds. I think, distinction between consonants and vowels was realized much late. Egyptians and/ or Western Semites possibly heard not syllables, but only consonantal sounds.<br> :::: ~ Vadim Cherny<ref>http://lists.ibiblio.org/pipermail/b-hebrew/2005-April/023283.html</ref><br> ...<br> ::: Proto-Hebrew was unambiguous: the language had a single vowel /a/, which later evolved into other vowels according to syntactical accent. Differentiation of vowels runs exactly along morphological differentiation. Written languages beyond the Egyptian and West Semitic [languages] differentiate vowels even in shorthand writing. To omit the vowels is odd – unless vocalization was unessential or unambiguous.<ref>http://vadimcherny.org/hebrew/protohewbrew_single_vowel.htm</ref> ...<br> * 2) the Semitic-centric vowel inventory of |a-i-u| (in the sense of templatic inflectional root patterning) could have existed since Prehistoric Egyptian times. We'll call this theory '''The |a-i-u| Vowel Semitic-centric Theory'''.<br> ::: Popular theory among a group of scholars ... the |a-i-u| theory can add an extra layer of Semitic-ism that can distract from the identity of the Egyptian language as noted by several scholars opposing the |a-i-u| theory.<br> * 3) '''Pharaonic Matres Lectiones''' existed since the Old Kingdom, this appears to stem from New Kingdom syllable writing as well as other Semitic languages which utilized a similar system. In this theory the semi-vowels are as follows<ref>https://www.academia.edu/6181590/New_Method_to_Vocalize_Ancient_Egyptian_Based_on_Specific_Offering_Texts_of_a_Poetic_Nature .. pg 21</ref><ref>http://lingwhizt.blogspot.com/2010/01/pharaonic-egyptian-hieroglyphs-1-vowels.html</ref>:<br> ::: Ꜣ > a (a guttural/pharyngeal ''a'' sound)<br> ::: ꜥ > a (a uvular/palatal ''a'' or ''l, j, y'' sound)<br> ::: j/y > i (breathy ''a, e, i'' sound)<br> ::: w > u/o (nasal vowel u /o )<br> ... * In my own opinion, after relentlessly researching and studying the Egyptian language, I feel confident enough to opine that all three theories were used in Ancient Egyptian, in some way, as followed by the below rules: # 1 - The a-Vowel Theory existed orthographically, unless /i/ or /u/ were intended as both vowels and consonants, i.e.: : ḥrw - day, I opine was originally pronounced: ḥarǔ (or ḥară, depended on vowel harmony), and in the plural it was most likely amended to ḥərăw (ḥrw.w) with the addition of the plural marker -w. Colloquially, and especially in fast speech, ḥarú was shortened to "ḥaw", interestingly the plural stayed the same "ḥərăw". # 2 - The Semitic Theory also existed because there were 3 vowels being used: a, u, i, and all were used (I'd also like to add that the vowels ə-schwa and /e/ most likely existed alongside /a, u, i/) # 3 - Matres Lectionis also existed in orthography, especially in group-writing, because it assisted in separating words into the proper syllables. === Realization of Egyptian Vowels <ref>References taken from: ... https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ...... https://copticsounds.files.wordpress.com/2010/02/the-interpretation-of-the-coptic-vowel-system.pdf</ref>=== The following may be applicable using any theory:<br> '''a'''<br> * Could have had one (or more) of these three vowel types, especially in regards to phonetic environments and its relationship to adjacent consonants:<br> : an [[w:Open central unrounded vowel|open central unrounded vowel (ä)]] -- Spanish r<u>a</u>t<u>a</u> <br> : an [[w:Open back unrounded vowel|open back unrounded (ɑ)]] -- similar to American English - h<u>o</u>t but pronounce it like an /a/; sp<u>a</u>, p<u>a</u>lm<br> : or [[w:Near-open front unrounded vowel|near-open front unrounded vowel (æ)]] -- American English c<u>a</u>t, <u>a</u>sh, l<u>augh</u>, h<u>a</u>t * During the Late New Kingdom stressed /a/ turns into stressed /o/. There are periodic exceptions as well as confusion in regards to a stressed /a ~ o/ throughout the Coptic phase of the language (this is very similar to Hebrew).<br> * In Coptic, the vowel /ɑ/ is typically represented by ⲁ, and its presence may be an indicator of emphasis spread in the same syllable, for example, ⲥⲁ (used in the construction 'man of [trade]') is transcribed ⟨sˤɑ⟩ in medieval Coptic-Arabic papyri and in some environments /a/ is a more forward [æ]<br> '''i'''<br> * Could have had one of two pronunciations:<br> : [[w:Near-close near-front unrounded vowel|near-close near-front unrounded vowel (ɪ)]] -- American English s<u>i</u>t, l<u>i</u>ttle : [[w:Close front unrounded vowel|Close front unrounded vowel (i)]] -- American English gr<u>ee</u>n * In early New Kingdom, short stressed /i/ turns into short stressed /e/. This can also be regarded as a regular development in most unstressed syllables if utilizing < i ><br> * According to the ''Semitic-centric |a-i-u| Vowel Theory'', at a later date, |i > e| and short stressed /u/ merged into /e/<ref>A phonetic evolution which probably did not affect the phonological level is /i:/ > [e:] in proximity of /ʔ/ and /j/.</ref>.<br> '''u'''<br> * It is to be noted that ''/u/'' did not appear to be a functional vowel in ancient Egyptian. The only indication of it's possible existence is in Akkadian cuneiform and it's relationship to Coptic reflexes (not including /u/ used as an allophone of /w/). This indirectly explains the confusion of /u/ when scholars attempt to reconstruct the vowels in nouns, as if /u/ had not existed as an independent sound before the Canaanite Vowel Shift, then those words which were believed to have used /u/ fall under the normal /a/ paradigms of the a-Vowel Theory.<br> * Original ''/u/'' may have been pronounced as a [[w:Close back rounded vowel|close back rounded vowel (u)]] in all positions<br> * or a [[w:Near-close near-back vowel|near-close near-back vowel (ʊ)]] -- like American English h<u>oo</u>k / f<u>u</u>ll but more on the upper of mouth with lips more compressed * According to the ''Semitic-centric |a-i-u| Theory'' -- At some point between the Middle Kingdom and Late Kingdom ''long stressed u'' may have been pronounced as a [[w:Close back unrounded vowel|close back unrounded vowel (ɯ)]] due to the speakers' adaptability to enunciate ''(u)'' as an ''unrounded vowel'' in relation to the vowels /a, i/ - that is articulating /u/ with the lips ''unrounded'' rather than pressed together, just like one would pronounce /a/ or /i/<ref>It is possible but ''less likely'' that a ''long stressed u'' may have turned into a ''long stressed ʊ'' (at some point in the Middle Kingdom or Late Kingdom) and not long after that it may have been pronounced as an ''unrounded near-close near-back vowel'' (ɯ̽) due to the other vowels being ''unrounded''. Though since a ''long stressed ʊ'' is rather rare among North African languages (ɯ̽ is even more rare) this is majorly an unproven hypothesis but just as possible.</ref>. <br> * Also According to the ''Semitic-centric |a-i-u| Theory'' -- During the Late New Kingdom long stressed /u/ turns into long stressed /e/.<br> '''o'''<br> * Late Egyptian introduced to the Egyptian language a new sound, /o/. There are basically two theories in relation the ''o''-vowel:<br> : '''The Standard Interpretation''' - the difference between Ⲱ ~ O was of quantity/length and was based upon classical Greek: :: Ⲱ = long /ō/ :: O = short /o/ : or '''The Quality Theory''' - the difference between Ⲱ ~ O was of quality (a term in phonetics for the property that makes one vowel sound different from another), which is based upon research by Kuentz who questioned the ''standard interpretation''. Worrell mentions coarticulation in relation to the ''vowel quantity'' hypothesis (following Vycichl) as a factor behind some of the variation. In his opinion, there were two variants for /e/ and /o/, a close one [o] near front consonants (such as /j/ and /w/) and an open one [ɔ] used with back consonants (such as /ħ/, a voiceless pharyngeal fricative). Likewise, there were an open [ɛ] and a close [e] treated along the same principles)<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ... pg 108</ref>. In this representation, we have:<br> :: Ⲱ = [[w:Open-mid back rounded vowel|Open-mid back rounded vowel (ɔ)]] -- American English th<u>ough</u>t but lower in throat<ref>It is believed, in general, that in some phonetic environments, /o/ is a more open [ɔ] no matter what theories are followed.</ref> :: O = [[w:Close-mid back rounded vowel|Close-mid back rounded vowel (o)]] -- American English c<u>o</u>mb, <u>o</u>ld, teleph<u>o</u>ne * The presence of /o/ appeared to only exist after the Canaanite Vowel shift, in a similar distribution to Hebrew.<br> '''e'''<br> * [[w:Close-mid front unrounded vowel|Close-mid front unrounded vowel (e)]] -- American English gr<u>ea</u>t without the diphthong sound at the end * [[w:Open-mid front unrounded vowel|Open-mid front unrounded vowel (ɛ)]] -- American English <u>air</u> without diphthong sound at the end === Diphthongs and Triphthongs === In order to understand how diphthongs and triphthongs were pronounced, it is necessary to fully understand the way the vowels utilizing them were used. A majority of the following examples are taken from Coptic with reference to the hieroglyphics.<br> ==== The Egyptian Semivowels ==== Sonja Dahlgren suggests that stressed syllables and unstressed ones both had a vocalic /u/ in Coptic, dependent on the phonemic environment, and therefore /i/ was probably also sometimes vocalic and sometimes consonantal. Depuydt (2003, 351-353) claims that the variation is partly conditioned by grammatical distinctions, the indefinite article OⲨ <ou>, /u/ being sonantic before nouns, but consonantic when preceded by some prefixal elements, such as certain conjugation bases and prepositions. These are, for example,<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1</ref><br> : ⲈⲨ < eu > (prep., 'to a..') : ⲀⲨ < au > (conjugation base of the perfect) : ⲈⲨ- < eu- > (circumstantial converter)<br> ===== [w] (labiovelar approximant) ===== Sonja Dahlgren is not sure that the distinction between vocalic and consonantic is anything but a phonetic 'accident'. Depuydt himself believes this to be a simple result of speech rhythm, < ou > being pronounced as /w/ in rapid speech and as /u/ in slower articulation. Furthermore, Depuydt shows examples of this ‘sonantic/consonantic’ variation between two forms of the same verb, ⲤⲀϨOⲨ (sahou) 'curse' in absolute state (sonantic), and ⲤϨOⲨⲰⲢ (shouōr) ('curse' in status pronominalis). There are other examples, but in all of them the same pattern actualises, it seems to follow the same rules in Coptic as in nonstandard renderings of Greek, be it Greek texts or Greek loanwords in Coptic. A symmetrical alternation between consonants and vowels seems to be what was wanted, the phonemes being realised as consonantal after or before a vowel and vocalic in between two consonants or a consonant cluster.<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1</ref><br> : ⲤⲰOⲨⲚ^{^B}, ⲤOOⲨⲚ^{^SF} <sōwun> - to know<ref>https://copticsounds.files.wordpress.com/2012/10/ishak-emile-maher-the-phonetics-and-phonology-of-the-bohairic-dialect-of-coptice280a6-d-phil-thesis-university-of-oxford-1975-volume-2.pdf ... pg 693 </ref> (swn - recognize; know)<br> :: ⲤOⲨⲚ-^{^S}, ⲤOⲨⲰⲚ=^{^SFB} <suwōn>, ⲤⲈOⲨⲰⲚ=^{^S} as in ⲤOⲨⲰⲚOⲨ <suwōnu> - to know them<br> : ⲦⲰOⲨⲚ^{^SA²BF}, ⲦⲰⲰⲚ^{^SA²} - to arise (dwn - to stretch out)<br> :: ⲦOⲨⲚ-^{^S}, ⲦⲈⲚ-^{^B}, ⲦⲰOⲨⲚ=^{^SO}, ⲦⲰⲚ=^{^SBF}, ⲦⲰⲰⲚ=^{^F} : ⲤⲀϨOⲨ - curse (absolute state) - Ⲥ͡ϨOⲨⲰⲢ - status pronominalis * <w> is never lost before the stressed vowel.<br> * <w> can be preserved or lost in pretonic position. The conditions are not clear. Sometimes there is dialectal variation in Coptic<ref>Examples of this is given in Carsten Peust's book pg 149.</ref>.<br> * If a cluster of two glides directly follows the stressed vowel, only one of them is preserved in Coptic. Two different developments are possible for a cluster of two glides one of which is <w>. There appears to be no rule to predict which development applied<ref>Osing (1976a: 28-30) assumes that the development is conditioned by the quality of vowels which he assumes to have intervened between both glides. His rules can be summarized as follows: 1) if one of the glides was -w-, then it was preserved if the intervening vowel was -a-, 2) as an exception to this rule, the sequence -āwaw renders -OⲨⲒ(Ⲉ) ~ⲰⲒ if the intervening vowel was -i-, then j was preserved unless the stressed vowel of the word was i; 4) in all remaining cases (including the cases of intervening -it-), none of the consonants was preserved. Schenkel (1979) discusses Osing's rules in detail and proposes some modifications (Schenkel 1979: 389). However, evidence for determining these intermediate vowels is weak; according to our reconstruction there were no such vowels at all... ... Carsten Peust pg 146.</ref> and the Coptic dialects may show different developments:<br> : 1) The first possibility is that Coptic has /w/, no matter whether <w> appears in the first or in the second position of the cluster in Egyptian. A good explanation would be that assimilation took place at some stage of the language:<br> :: jry.w - fellows ~ ⲈⲢⲎⲨ^{^S.}, ⲈⲢⲎOⲨ^{^B.} ~ jarjǔw?!<br> :: gꜢw - narrow ~ ϬⲰOⲨ ~ gāꜢaw<br> :: gwꜢ - to push off ~ ϬⲰOⲨ^{^S.}, ϪⲰOⲨⲚ^{^B.} ~ gāwaꜢ<br> :: <u>t</u>Ꜣw - wind ~ ⲦⲎⲨ^{^S.}, ⲐⲎOⲨ^{^B.} ~ <u>t</u>ǔꜢaw<br> :: <u>t</u>Ꜣ.w - to be taken (stative) ~ ϪⲎⲨ^{^S.}, ϬⲎOⲨ^{^B.} ~ <u>t</u>ǔꜢaw<br> :: djw - five ~ ϮOⲨ^{^S.}, ⲦⲒOⲨ^{^B.} ~ dǐjaw<br> ::: Note: The combination Ꜣw/jw usually renders OⲨ^{^Copt}<br> : 2) Another possibility is that the first consonant survives in Coptic. Thus, if <w> is the first consonant, it is preserved:<br> :: nǐwiꜢ - to see ~ ⲚⲀⲨ<br> :: ḥāwaꜢ - to be rotten ~ ϨOOⲨ^{^S.}, ϨⲰOⲨ^{^B.}<br> : 3) If <Ꜣ> is the first consonant, it can be preserved or lost in Coptic, as is true for word-final <Ꜣ>:<br> :: ḥkꜢw - magician ~ ϨⲀⲔO^{^S.}, ⲀⲔⲰ^{^B.}<br> :: ḥfꜢy.w - snakes ~ ϨⲂOⲨⲒ^{^S.B.}<br> :: sbꜢ.w - discipline ~ ⲤⲂOⲨⲒ^{^S.B.}<br> :: zꜢw - beam of wood (since Middle Kingdom) ~ ⲤOⲒ^{^S.B.}<br> :: zꜢw - a town (Sais) ~ ⲤⲀⲒ^{^S.}, ⲤⲀ^B. - attested as sa-a-a (probably to be interpreted [saj^ɘ] or similarly) in Neo-Assyrian cuneiform transcription (see Borger 1996: 20)<br> ::: '''Note''':<ref>Carsten Peust pg 150.</ref> If the preceding consonant was lost, the glide comes in direct contact with the stressed vowel. Therefore it preserves its consonantal nature in Coptic, however <j> is lost in the Sahidic dialect (on the phonological interpretation of the Bohairic forms):<br> :::: jrj.j < jrj.w - (he) is done (3rd pers masc stative) ~ O^{^S.}, OⲒ^{^B.}, ⲀⲒ^{^F.}<br> :::: mrj.t - to love ~ ⲘⲈ^{^S.}, ⲘⲈⲒ^{^B.}, ⲘⲈⲒⲈ^{^A.}<br> :::: hꜢj.t - to fall ~ ϨⲈ^{^S.}, ϨⲈⲒ^{^B.}, ϨⲈⲈⲒ^{^A.}<br> :::: r-prj.t - temple ~ ⲢⲠⲈ^{^S>}, ⲈⲢΦⲈⲒ^{^B.}, ⲢⲠⲈⲈⲒ^{^A.}; ⲀⲢⲠⲀⲈ / ⲀⲢΨⲀⲈ^{^{Old Nubian}} - borrowed from the Bohairic form.<br> :::: mꜢw<u>t</u> - to think (since Middle Kingdom) ~ ⲘⲈⲈⲨⲈ^{^S.A.}, ⲘⲈⲨⲈ^{^B.}<br> :::: <u>t</u>bw.t - sandals ~ ⲦOOⲨⲈ^{^S.A.}, ⲐⲰOⲨⲒ^{^B.} - with irregular loss of [ b ].<br> ::: '''Note II''':If the preceding consonant was not lost, then it directly precedes the glide in Coptic. There is thus a tendency for the glide to be vocalized. <w> is preserved as a consonant in some dialects of Coptic, and vocalized to /u/ in others. <j> is always vocalized; however in most varieties of Coptic it does not develop into /i/ - as might be expected -, but it merges with /Ⲉ/. Only in certain varieties of Lycopolitan is it indeed written < Ⲓ > and thus kept distinct from the final vowel /ə/ that is written < Ⲉ >.<br> :::: rsw.t - dream ~ ⲢⲀⲤOⲨ^{^S.} [rasu], ⲢⲈⲤOⲨ^{^A.}, ⲢⲀⲤOⲨⲒ^{^B.} [raswi], ⲖⲈⲤⲂⲒ^{^F.}<br> :::: mtw.t - poison ~ ⲘⲀⲦOⲨ^{^S.} [matu], ⲘⲈⲦOⲨ^{^A.}, ⲘⲀⲐOⲨⲒ^{^B.} [matwi], ⲘⲈⲦⲂⲒ^{^F.}<br> :::: pḥ.wj - back ~ ⲠⲀϨOⲨ^{^S.A.} [pahu], ΦⲀϨOⲨ^{^B.}<br> :::: šnw.t- granary ~ ϢⲈⲨⲚⲒ^{^B.} [shewni] with metathesis.<br> :::: <u>t</u>zj.j > <u>t</u>zj.w ( < w > is only graphical) - to be exalted (stative) ~ ϪⲀⲤⲒ^{^L.}, ϪOⲤⲒ^{^S.}<br> :::: mnjw - herdsman ~ ⲘⲀⲚⲈ^{^S.}, should be ⲘⲀⲚⲒ in in Lycopolitan which is accidentally not attested.<br> : 3) Some words are attested with both developments which may be distributed over different dialects:<br> :: šmꜢ.w - aliens ~ ϢⲘⲘOⲈⲒ^{^S.}, ϢⲘⲘⲰOⲨ^{^B.}; But -ⲰOⲨ^{^B.} may also be a secondary development<ref>Carsten Peust pg 146.</ref>.<br> :: gꜢw - to be narrow; the infinitive develops into ϬⲰOⲨ^{^S.} and the participle form is ⲔOⲨⲒ^{^S.} - narrow.<br> ::: The pluralic adjective ꜥꜢ.w - great, is preserved as the final component of certain compounds as follows:<br> :::: ⲢⲢ-ⲰOⲨ^{^S.}, OⲨⲢ-ⲰOⲨ^{^B.}, ⲢⲢ-ⲀⲒ^{^A.}, ⲈⲢ-OⲨⲒ^{^M.} - kings<br> :::: ϨⲖⲖ-OⲈⲒ^{^S.}, ⳊⲈⲖⲖ-OⲒ^{^B.}, ⳈⲖⲖ-ⲀⲒ^{^A.} - old men<br> :::: ⲈⲒⲢ-ⲰOⲨ^{^S.}, ⲒⲀⲢ-ⲰOⲨ^{^B.}, ⲒⲈⲢ-ⲰOⲨ^{^A.} - rivers<br> : 4) We have an irregular development in<br> :: rwj - to depart, go away ~ ⲖO^{^S.A²}, ⲖⲀ^{^S.F.} ... Carsten Peust states: It is unclear whether stress was originally on the first syllable (ra'wVj) or on the second (rV'waj). The vowel class can be explained in both cases, but the loss of <w> is irregular in any case... There are several other words which follow a similar pattern:<br> :: zwr (> zjr) - to drink ~ ⲤⲰ^{^S.B.}, ⲤOⲨ^{^S.A.A²}<br> :: nꜥy.j (> nꜥy.w) - to go (stative) ~ ⲚⲀ<br> : 5) If the cluster contains only <Ꜣ> or <j>, then Coptic has /j/:<br> :: mꜢj - lion ~ ⲘOⲨⲒ^{^S.B.} ( = muj)<br> :: ḥꜢ.ty-j - my heart ~ ϨⲦⲎⲒ<br> ::: The following example is similar, but /j/ is lost in Sahidic:<br> :::: <u>d</u>y.j - (he) is given (3rd pers. sg. masc. stative) > <u>d</u>y.w (w> is only graphical), ⲦO^{^S.}, ⲦOⲒ^{^B.} , ⲦOⲒⲈ^{^L.}, ⲦⲈⲒⲈ^{^A.}.<br> ===== [j] (palatal approximant) ===== For example, the phoneme is consonantal in ϨⲒOⲘⲈ (hiome, hjomə), where it precedes another vowel, but vocalic in ⲤϨⲒⲘⲈ (shime, shimə), where it is situated in between two consonants. In ϤⲒ (fi), /fi/ it is again vocalic because a word consisting of only two consecutive consonants is difficult to pronounce, but consonantal in ϤⲀⲒ (fai), (faj), because it follows another vowel. So it seems that after or before vowels, it was probably realised as a glide in the spoken language; it was probably all related to ease of articulation in spontaneous speech. No doubt this allophonic variation was used to create morphological distinctions in Coptic (maybe more so than conditioned by it), but it does appear to prove that both ⲈⲒ < ei > and OⲨ < ou > had a vocalic realisation, contrary to what Haspelmath presents in his analysis of these two phonemes. And these phonological rules were probably used also in second language production.<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1</ref><br> * In Sahidic Coptic, the vowel version is always spelled < ⲈⲒ > in initial position; ⲈⲒⲚⲈ ~ (íne), ⲈⲒⲤ ~ (ís). Internally or in final position both < Ⲓ > and < ⲈⲒ > are used but < Ⲓ > is preferred. * In Sahidic Coptic, the combination < ⲈⲒ > less commonly < ⲈⲈⲒ > can indicate two separate letters, a knowledge of the grammar is needed to distinguish between the two uses, for example, ⲈⲒ has the value Ⲉ (vowel) + Ⲓ (semi-consonant):<br> :: 1) in the demonstrative adjectives: ⲠⲈⲒ, TⲈⲒ, ⲚⲈⲒ ... ⲠⲈⲒⲢⲰⲘⲈ (pey-rōme)... same is true of ⲠⲀⲒ, TⲀⲒ, ⲚⲀⲒ :: 2) in the first person verbal prefixes of the forms -ⲈⲒ, -ⲚⲈⲒ, -ⲘⲈⲒ :: 3) and in a few isolated words like; ⲈⲒⲈ (eye) - a participle, ⲈⲒ (ey) - come *There are specific rules in how (and when) this sound was pronounced according to Coptic<ref>The following rules are taken from Carsten Peust's book pgs 143 and on....</ref> [the same can be assumed in the earlier stages of the language with some modifications<ref>We can observe that morphophonological alternation is found only in late words which are first attested in the New Kingdom. The explanation seems to be that morphophonological alternation in more ancient words was eliminated early by analogical levelling... Carsten Peust's book pg 143.</ref>): * Glides which directly precede the stressed vowel are normally preserved in Coptic:<br> :: ⲈⲒOⲘ (ym) - sea<br> :: ⲒⲈⲒⲢⲈ (jr.t) - eye<ref>Proto-Afro-Asiatic: ʔir - eye... http://starling.rinet.ru/cgi-bin/response.cgi?root=config&morpho=0&basename=%5Cdata%5Csemham%5Cegyet&first=1&off=&text_proto=&method_proto=substring&ic_proto=on&text_meaning=&method_meaning=substring&ic_meaning=on&text_dem=&method_dem=substring&ic_dem=on&text_cpt=&method_cpt=substring&ic_cpt=on&text_cptmean=&method_cptmean=substring&ic_cptmean=on&text_ooo=&method_ooo=substring&ic_ooo=on&text_ppp=&method_ppp=substring&ic_ppp=on&text_fff=&method_fff=substring&ic_fff=on&text_mmm=&method_mmm=substring&ic_mmm=on&text_aaa=&method_aaa=substring&ic_aaa=on&text_bbb=&method_bbb=substring&ic_bbb=on&text_lll=&method_lll=substring&ic_lll=on&text_sss=&method_sss=substring&ic_sss=on&text_notes=&method_notes=substring&ic_notes=on&text_any=eye&method_any=substring&sort=proto&ic_any=on.</ref><br> : But <j>/<ɜ> can also be lost. This concerns the following cases:<br> : 1) In most verbs <j> / <ɜ> is lost even before the stressed vowel<ref>The importance of the morphological category suggests that analogical levelling has taken place here. Fecht (1960: XIVf.) provides a plausible explanation that many verbal forms of the suffix conjugation, which was very familiar to the older language before it became almost extinct in Coptic, had suffixal stress. /j/ would thus have been lost regularly here in pretonic position, whence the /j/-less variety was extended by analogy to forms bearing initial stress such as the infinitive.</ref><br> : 2) <j> is usually lost before ^{^Copt}Ⲏ (rule by Vycichl 1940: 87)<br> :: jꜢw.t - cattle, conserved in ⲦⲂⲚ-Ⲏ^{^S.}, ⲦⲈⲂⲚ-Ⲏ^{^B.} - animal ... Note: jwꜢ^{^MEg} - ox, long-horned cattle; 'w.t^{^MEg} - small cattle, goats, herds<br> :: jp.t - number ~ ⲎⲠⲈ^{^S.}, ⲎⲠⲒ^{^B.}<br> :: jrp - wine ~ ⲎⲢⲠ^{^S.B.}<br> :: -- An exception is Ꜣbw - Elephantine (name of a town) > ⲒⲎⲂ^{^S.}. Note also rmy.t - tear (since Middle Kingdom) > ⲢⲘⲈⲒⲎ but ⲈⲢⲘⲎ^{^B.}<br> : 3) There's a few others in Coptic with unexplained reasons for the loss of the glide.<br> * A glide is usually retained if it directly follows the stressed vowel<ref>However, there are several cases of loss which remain unexplained... -O^{^Copt} [ꜥǎꜢ^{^MEg}] - to be great ... ect. Peust pg 145.</ref>:<br> :: OⲨϪⲀⲒ [wi<u>d</u>ǐɜ] - to be healthy<br> :: ϨⲀⲒ [hy] - husband<br> * <j> / <ɜ> is always lost in pretonic position<ref>Exception: If in late compounds a stressed syllable loses stress secondarily, /j/ can move into an atonic syllable: jtrw-ꜥꜢ - big river > ⲈⲒⲈⲢO^{^S.}, ⲈⲒⲀⲢO - Nile, a compound of 1) jtrw "river, Nile" > ⲈⲒOOⲢ^{^S.}, ⲒOⲢ^{^B.} "canal" and 2) ꜥꜢ - big, great > -O^{^S.B.}</ref>:<br> :: ⲀⲚOⲔ - independent 1st singular pronoun ... ect.<br> ===== Pronunciation Rules of eta-Ⲏ<ref>Mainly using Bohairic Old Pronunciation as the source with periodic deviations.</ref>: According to Old Bahairic ===== * eta < Ⲏ > can either be pronounced /a/ as in b<u>a</u>th, or /i/ as in qu<u>ee</u>n<ref>The [[w:Coptic pronunciation reform|Coptic pronunciation reform]] used this pronunciation for all Coptic Ⲏ</ref>.<br> * /a/ in closed syllables :: OⲨⲎⲂ <uāb> :: ϨⲒⲘⲎⲢ <himār> :: ⲦⲎⲢOⲨ <dar-u> :: ⲠϨⲎⲦ <ebhāt> :: ⲚⲀⲎⲦ <naād> :: ⲤⲎⲘ <sām> old testament name :: ⲦOⲨⲎⲦ <ţuwāt> :: ΓⲀⲂⲢⲒⲎⲖ <ġabriyāl> :: ΔⲀⲚⲒⲎⲖ <danyāl> :: ΔⲒⲀⲚⲎ - Diana (name) :: ⲈϤⲢⲎⲘ <afrām> :: ⲘⲰⲨⲤⲎⲤ <musās> or <mōysās> :: Some exceptions include, but are not limited to:<br> ::: (ϩ)ⲀⲘⲎⲚ <amīn> - borrowing from Ancient Greek ἀμήν (amḗn), from Biblical Hebrew אָמֵן‏ (ʾāmēn) ::: ⲒⲎⲤ (from ⲓⲏⲥⲟⲩⲥ which is a borrowing from Koine Greek Ἰησοῦς (Iēsoûs), from Biblical Hebrew יֵשׁוּעַ‏) is pronounced <yasūs> but more commonly <yisūs>, <īsūs>, <yisōs>, <īsōs> - Jesus ... coincidentally, this also explains the bivalent enunciation of Isis - ⲎⲤⲈ<br> < Ⲏ > in open syllables had two outcomes both used interchangeably without a reasonable explanation ''but'' in accordance with the indirect evidence of the ''Egyptian monophthongization theory'' stated above, it appeared /a/ was the original intended pronunciation, with an option to instead pronounce /i/ if one chose to especially if it was a reduction of a diphthong<ref>... according to Gignac, eta had /i/ as allophone within the group of long stressed vowels and within the short stressed vowels, however, the allophone of eta was /a/... </ref>. Despite the theory believed, a general rule is shown below:<br> * /i/ in open syllables:<br> :: ΦⲎ <bi> or <bei> :: ϢⲎⲢⲒ <šīri> :: ⲀⲢⲔⲎⲖⲀOⲤ <ark-ī-laos> * and /a/ in open syllables<br> :: ⲬⲎ <ka> :: ϨⲎ <ha> - front :: ⲘⲎ <mā> - not :: ⲘⲒⲎ <mjā> - lioness :: ⲚⲎ <na> :: ⲬⲎⲘⲒ <kāmi> - Egypt (ⲔⲀⲘⲒ is also attested) :: ⲔⲎⲚⲒ <kāni> - fat :: ϨⲀⲚOⲨⲎⲂ <hanuāb> * < ⲎⲒ & ⲎOⲨ > preferred /a/:<br> :: ⲎOⲨⲒ <ăwi> :: ⲎⲒ <ăy> or <āj> - house :: ⲢⲎⲒ <rāy> - a kind of fish :: ⲘⲀⲐⲘⲎⲒ <mǎt-mai> :: ⲈⲐⲚⲎOⲨ <at-nao> :: ⲚⲒΦⲎOⲨⲒ <nei fǎui> or <nifāwi> :: ϨⲢⲎⲒ <ɛh-rāj> - upward :: ⲈⲠⲒⲎⲒ <abi-ai> :: ⲤⲎⲒⲚⲒ <saj-ni> - physician :: ⲘⲎⲒⲚⲒ <maj-ni> - sign :: Example of co-articulation next to /s/ => ⲠⲒⲤⲎOⲨ <bi-siio> In foreign transcriptions, there were several outcomes, in many instances it could also be /ě/,/ē/<ref>Eta and epsilon were also frequently confused with one another so they were clearly very close in value (when pronounced like an /e/). In other words, even though the bivalency of Coptic eta strictly speaking concerns the realisation of eta /ē/ as /i/ or /a/ following Coptic phonological processes, it can be applied in the analysis of Narmouthis Greek nonstandard variants as /ē/ and /e/ were phonetically found so similar in quality to each other that they were nonstandardly replaced by one another, in Narmouthis Greek ostraca as well as in Coptic native language usage... https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 112</ref>:<br> :: ⲂⲎⲐⲖⲈⲈⲘ <bě-ět-laam> or <bǐ-ǐt-laam> :: ⲈⲢⲰΔⲎⲤ <ěr-ô-das> or <irudas> :: ϨⲎΓⲈⲘⲰⲚ <ě-ğǎ-mon> === Pronunciation Rules of Diphthongs and Triphthongs === Diphthongs and triphthongs in combination with the semi-vowels are one of the most trickiest things to master not only in Coptic but in the hieroglyphics as well... so, because of this, I have decided to jot down some pointers on how best to recognize these phonetic elements. I based these rules on the Old Bohairic Pronunciation with some additional notes from other sources whenever it deviates from the normal rules.<br> : -ⲀⲒ <ay> : -ⲎⲒ <ay>, <āy> : -ⲈⲒ <ay> or <ey> : -OⲒ <oy>, <ōy> : -ⲰⲒ <ōy>, <oy> :: * Sometimes Ⲓ disappears in -OⲒ / -ⲰⲒ and it is thus pronounced <ō> ::: OⲨⲰⲒⲚⲒ ~ OⲨⲰⲚⲒ <wōni> ::: ⲰⲒⲔ ~ ⲰⲔ <ōk> ::: ϬOⲒⲤ ~ ϬOⲤ <šōš>, <šōs> : -ⲀⲨ <aw> :: * The /w/ sound of -ⲀⲨ is sometimes lost and the combination pronounced /a/ (notice that this example is in unstressed position):<br> ::: fawķānī (an Arabic loan word) ~ fagāni :: * On the other hand, CA. /aw/ is usually monophthongized in EA., and in other Arabic dialects, into /ō/ ... Similarly -ⲀⲨ, -ⲈⲨ in ritual expressions and in Coptic and Greek loan-words in Arabic are sometimes monothphongized into /ō/. :: * Ⲱ sometimes stands for ⲀⲨ in dialectal equivalents<br> ::: ⲈⲒⲰ for ⲈⲒⲀⲀⲨ - flax ::: ⲘⲰ for ⲘⲀⲀⲨ - mother ::: 'ⲘⲘⲰ - there ::: ⲚⲰ - see ::: ⲚⲰ - time ::: ⲚⲰ - to them ::: ⲤⲚⲰ - two : -ⲈⲨ <aw> or <ěu> :: ϢⲈⲨⲚⲒ (šnw.t) - barn, is always pronounced <šūna> : -ⲒOⲨ <īw>, <(i)yū> :: ⲤⲒOⲨ <sīw> also heard <siyū> and <sio> :: ⲒOⲨΔⲀⲤ <yudās> : -ⲎⲨ <āw>, <aw> : -OOⲨ <ow>, <ū> : -ⲰOⲨ <ōw>, <ō> sometimes <aw> :: But <sōwn> ⲤⲰOⲨⲚ sometimes sounds like <sōun> :: and after /o/ or /ō/ the /w/ is sometimes lost: hō, hū - ϨOOⲨ; mō - ⲘⲰOⲨ<br> : -ⲒⲀ <ya> : -ⲒⲈ <ya> or <ye> : -ⲒⲎ <yā> or <ya> :: ⲘⲒⲎ <mjā> - lioness :: (Ϩ)ⲒⲎⲂ <(h)jāb> - sewing : -ⲒO <yo> or <yō> : -ⲒⲰ <yo> or <yō> : -OⲨⲀ <wa> :: ⲈⲐOⲨⲀⲂ <atwāb> :: ⲬOⲨⲀⲂ <kwab> : -OⲨⲈ <wa> or <we> :: ⲈⲤOⲨⲈⲚ <asoúān> : -OⲨⲎ <wā>, <wa> sometimes <wī> :: OⲨⲎⲂ <wāb> :: ϪⲈ OⲨⲎⲒ <ja waj> :: OⲨⲎⲢ <wīr> : -OⲨⲒ <wi>, <uwi>, and sometimes <ūj> in some words :: OⲨⲒⲚⲀⲘ <(u)winam> :: ϨOⲨⲒϮ <(h)uwīdi> :: OⲨⲒ <wī> :: ⲔOⲨⲒ <kūy> : -OⲨO / -OⲨⲰ <wo>, <wō> and rarely <'ūō> * It is not uncommon for some diphthongs to be monophthongized (for example with the usage of eta-Ⲏ, as shown in the above sections) * αι in Greek words included in Coptic texts is usually rendered by Ⲉ, less commonly by Ⲏ, Ⲁ or even Ⲩ. This may indicate the early tendency among the Copts to monophthongize diphthongs * In dialectal equivalents sometimes Ⲁ stands for ⲀⲒ === Unstressed Syllables === The unstressed syllable, in Egyptian, based upon renditions of Egyptian words in Coptic, Cuneiform, Arabic, Greek as well as other linguistic sources appears to have been a ''schwa-like'' vowel-^ə along with some indications of co-articulation with the adjacent consonant in some instances of unstressed syllables. Some dialects also show a different vowel in final vowel unstressed position, for example:<br> :: Sahidic and Achmimic = -Ⲉ (ⲢⲀⲘⲈ / ⲢⲀⲘⲎ<ref>Variation between η <ē> and ε <e> ... Variation between η <ē> and ε <e> occurs in the same environments as do the previous vowel changes, i.e. again near bilabials/nasals (/m/ classifies as both), /s/, liquids and interestingly, word-finally, which is probably indicative of a phonetic-level schwa. This consonantal articulation is especially clear in the cases where eta is what seems to be retracted to epsilon. Again, variation occurs both in Greek stressed and unstressed syllables... https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 105 </ref><ref>Ⲏ <ē> has been used to indicate schwa in an unstressed syllable before sonorants in Fayyumic, which is probably indicative of coarticulation again as sonorants tend to raise the vowel value – so before sonorants, the value of schwa resembled more a close vowel than an open one...https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ... pg 37 </ref>) :: Bahairic and Fayyumic = -Ⲓ (ⲢⲀⲘⲒ)<br> : ... Kasser (1991a) lists dialectal variants in which F7, a Fayyumic subdialect (according to Kasser an archaic, northern form of Fayyumic), has the form ''sôtom'' - hear, listen, in a list in which all other dialects, including other Fayyumic variants, have ''sôtem, sôtm'', or ''sôtme, sôtm(e)''. The stress was on the first syllable long vowel, leaving the final syllable unstressed. It seems clear that the various forms listed here employ different strategies in which to display the unstressed vowel’s quality, and bearing in mind that Coptic phonetically had no unstressed < o >, the F7 marking of the final syllable with < o > must be a graphic convention for schwa in that dialect. In Kasser (1991c), he elaborates that F7 specifically used < e > (sometimes i) after a closed tonic syllable, in a closed atonic syllable with a sonorant as the final, but < o > before the bilabials < m > and < b > (such as in sôtom). Other Fayyumic dialects (generally Fayyumic) used < e > also for this purpose. Marking the unstressed syllable with < o > is therefore an exception and possibly limited to some coarticulatory purposes as bilabials tend to lower the quality of close vowels, as mentioned before, as well as round the vowel quality<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ... pg 123</ref>...<br> * In reference to Coptic renditions of Greek words: <br> :: ... The first group consists of the depiction of the (often word final) unstressed syllable’s vowel, which fluctuates between /a/, /e/ and /o/, most often taking the graphemic variant <e>. This is probably due to Coptic influence, in which the reduced unstressed vowel was customarily marked with <e>, although certainly this could also be seen as fronting of /o/ to /e/ adjacent to coronal consonants<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 61</ref> ...<br> * In reference to Coptic renditions of Greek words: <br> :: ... there are instances where the same is happening in Greek stressed syllables. The vowel quality is altered, and often seems to follow that of the adjacent consonant, thus acting like the vowels in the unstressed syllables<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ... pg 60</ref>... ==== Syllabic Consonants ==== Among the examples cited by Layton are syllabic consonants /l/, /p/, and /b/. This could be what is going on in ⲖⲈⲂⲈⲚOⲨ(Ⲥ)<ref>There is also a ⲖⲒⲂⲈⲚOⲨ(Ⲥ) <libanos> attested as well.</ref> <lébenous> from the standard (λίβανος) <líbanos> whose vowels are all nonstandard – it is possible that the syllable peak was on /b/, and the surrounding vowels are simply assimilated to the quality of the consonant, /b/, a bilabial, able to lower the quality of close vowels, and raise the quality of open ones<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 130</ref>. <br> In Coptic, any consonant could be syllabic or non-syllabic, i.e. any one of the consonants could form the nucleus of a word and act as the syllable peak, and no vowel was necessary for a given syllable (Layton 2000, 28-30); however, mostly this concerned sonorants (Peust 1999, 263-264)<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 .. pg 42</ref>. One of the most distinctive features of Sahidic spelling is the short stroke placed over certain consonants or groups of consonants. This supralinear stroke, as it is called, indicates a syllable, but there is some disagreement among Coptic scholars on how this syllabification actually sounded in the spoken language. When the stroke is used over a voiced consonant such as N, it probably meant that the consonant is functioning as the vowel...like the final n of English button and sudden... The voiced consonants capable of having this syllabic pronunciation are β, λ, Μ, Ν, ρ, known mnemonically as the blemner consonants.<ref>http://bcharchive.org/2/thearchives/showthread6f53.html?t=162535</ref> Some examples of odd supralinear stroked or syllabic words<ref>https://copticsounds.files.wordpress.com/2010/02/syllabic-consonants-in-sahidic-coptic.pdf</ref>: : Ⲛ̄Ⲛ͡ⲚⲚⲀⲂⲈ (''b'' = Ϥ or OⲨ in this word) - the first ''n'' must have been separated by the 2nd ''n'' by a change of pitch or stress, otherwise the word would have been indistinguishable from: Ⲛ͡ⲚⲚⲀⲂⲈ. The second syllable must have been a long ''n'' to prevent further confusion with Ⲛ̄ⲚⲀⲂⲈ... in my opinion, Ⲛ̄Ⲛ͡ⲚⲚⲀⲂⲈ = n̩-nen-na-be, Ⲛ͡ⲚⲚⲀⲂⲈ = nen-na-be, Ⲛ̄ⲚⲀⲂⲈ = n̩-na-be, all with appropriated stress alignment when necessary. : Difference between the pair ϢⲖ͡Ⲗ and ϢⲖⲎⲖ (for example), could be a syllabic ϢⲖ͡Ⲗ (sh^ə-l-l̩ or esh-l-l̩) vs ϢⲖⲎⲖ (sh^ə-lēl). Same is said of Ⲃ͡Ϭ ~ ⲂⲎϬ and any similar pairs... something to note, in these examples in my opinion, we are probably more dealing with a reduced vowel rather than a syllabic word. : Words like ⲤⲤⲰⲦ͡Ⲙ and Ϣ̄ϢⲈ (in lieu of Ⲥ̄ϢⲈ) are rather odd. They are often regarded as some sort of consonant lengthening possibly resulting from a preceding/adjacent word or from an attached auxiliary unit (? need more information on this topic). Same is even more true of words like: ⲔⲔⲰ, ⲠⲠⲒⲚ and ⲦⲦO, with the initial syllable tending to be lengthened adjacent to a sonorous sound. ==== Coarticulation and Stress-Related Allophonic Distribution (in Arabic loan words)<ref>https://helda.helsinki.fi/bitstream/handle/10138/184140/Outcomeo.pdf?sequence=1 ...pg 146</ref> ==== Egyptian also has a phonological rule regarding vowel fronting or retraction according to the quality of the adjacent consonant, in Arabic philology called ''imāla''. Imāla is the Arabic linguistic term for the effect of consonantal coarticulation on vowels, meaning a vowel shift from /a, aː/ to /e, eː/ everywhere but near the emphatic consonants, uvulars, (to a lesser degree) the pharyngeal consonants /ħ/ and /ʕ/, and /r/. Examples of this phonological process are below using Arabic words rendered in Coptic:<br> * Unstressed /a/ retracted to /e/<br> : dānaq ~ ⲦⲀⲚⲈⲔ (tanek)<ref>The second syllable uvular /q/ should cause the original vowel value of /a/ to be retained but it seems to have raised to /e/. <a> was one of the vowel graphemes with which schwa was orthographically marked in Coptic but <e> was even more frequent for the purpose. Therefore it seems that whatever the unstressed vowel’s value in Arabic original, the final unstressed syllables were treated within the rules of Coptic phonological system, and marked accordingly using Coptic orthographic practices, exactly as second language Greek and Greek loanwords in Coptic were treated. </ref><br> * Retraction of /a/ to [ɑ] adjacent to a uvular stop<ref>([q], voiceless uvular stop [ɢ], voiced uvular stop [ɴ], uvular nasal [qʼ], uvular ejective [ʛ ], voiced uvular implosive (very rare) [ʛ̊ ] or [qʼ↓] voiceless uvular implosive (claimed to exist in Kaqchikel)</ref> : al-qārūra ~ ⲀⲖⲔⲀⲢOOⲢ (alkaroore) * Retraction of /u/ to /o/ before /r/ (in stressed position)<ref>Arabic loanwords, standard <ou> being replaced with <o> in a stressed syllable.</ref> : al-qārūra ~ ⲀⲖⲔⲀⲢOOⲢ (alkaroore) * Retraction of /u/ to /o/ after /r/ (in stressed position) : al-rūbʿ ~ ⲀⲢⲢⲰⲠⲀ (arrōpa)<br> * Retraction of /i/ to [ɑ] adjacent to pharyngealised stop :: al-miṯqal ~ ⲀⲖⲘⲀⲦⲔⲀⲖ (almatkal) * Retraction of /a/ to [ɑ] adjacent to pharyngealised stop :: al-miṯqal ~ ⲀⲖⲘⲀⲦⲔⲀⲖ (almatkal) * Raising of /a/ to /e/ adjacent to a velar stop<ref>[k], voiceless velar stop [ɡ], voiced velar stop [ŋ], voiced velar nasal [ŋ̊], voiceless velar nasal [kʼ], velar ejective [ɠ ], voiced velar implosive (rare) [ɠ̊ ] or [kʼ↓], voiceless velar implosive (unattested in normal words; some English speakers use it to imitate the "glug-glug" sound of liquid being poured from a bottle)</ref> (in original stressed position)<br> : al-kātib ~ ⲀⲖⲬⲈⲐⲒⲠ (alkʰetʰip) * Arabic ayin marked with Ⲁ <a> /a/<br> : al-rūbʿ ~ ⲀⲢⲢⲰⲠⲀ (arrōpa)<br> * Assimilation of article /l/ to /r/ adjacent to a coronal consonant<br> : al-rūbʿ ~ ⲀⲢⲢⲰⲠⲀ (arrōpa)<br> * Retraction of /a/ to [ɑ] after a uvular (in unstressed position) : al-qabāla ~ ⲀⲖⲔⲀⲠⲈⲖⲈ (alkapele)<br> * Raising of /a, aː/ to /e/ near /b/ and /l/ (in stressed position) : al-qabāla ~ ⲀⲖⲔⲀⲠⲈⲖⲈ (alkapele)<br> * Retraction of /i/ to /e/ before /r/ (in stressed position) : dǐrham ~ ΔⲈⲢϨⲀⲘ (děrham)<br> * Retraction of /a/ to [ɑ] after /h/? (in unstressed position) : dǐrham ~ ΔⲈⲢϨⲀⲘ (děrham)<br> What I can perhaps offer as further detail is the probable use of Coptic orthographic practices, i.e. word-final /a/ marking with <e>, i.e. phonetically schwa, and the use of /o/ instead of /u/ in stressed syllables.<br> The same applies for features stemming from Coptic phonology: for instance the allophony of /o/ and /u/ according to Coptic stress patterns is a feature related to the phonological structure of the language in terms of phoneme distribution, but again the outcome of it in spoken language seems phonetic because it is tied to the effect of the stress in the word: quite simply, the mid vowel /o/ cannot as easily hold a distinct phonetic value in an unstressed position, it will be easily reduced to schwa, whereas /u/, a close vowel, is easier to distinguish in any position.<br> ........... The importance of stress in Egyptian for (vowel) phonemic value can also be seen when looking at some attestations of the (e, i) variation. According to Girgis, unstressed (i) usually held its value in Greek loanwords in Coptic but in some instances, albeit rarely, it could vary with (e) as in λεгεωɴ from (legiōn) 'legion', and in some cases further on with the supralinear stroke. On the other hand, also stressed (i) could vary with all of the graphemes mentioned for the unstressed one, and likewise with Ⲉ (e), although even more rarely than in unstressed syllables; but again, even the vowel stroke can replace (i). It can therefore be concluded that although (i) could become subject to variation if it was in a weak position, it was nevertheless capable of sustaining its quality even in unstressed syllables.<br> ........... ... the date of the adoption of the word (Migdol<ref>which means either a tower (from its size or height), an elevated stage (a rostrum or pulpit), or a raised bed (within a river).</ref>) by the Egyptians probably preceded that of the well-known papyrus in which a scribe of conservative views bitterly laments that young fashionable Egyptians used a number of Semitic words alien to their true and better mother tongue. It apparently became changed from its true pronunciation after its importation into the Egyptian vocabulary because there is every reason to believe that the ancient Egyptian town names Ma-k-to-ra or Ma-k-ti-ra are this word<ref>https://books.google.com/books?id=wKxBAQAAMAAJ&pg=PA113&lpg=PA113&dq=egyptian+ancient+pronunciation+mAA+-+see,+watch&source=bl&ots=U1WVQxywPs&sig=5qn4hX9vdgp7dFf3lj8_442MC_8&hl=en&sa=X&ved=0ahUKEwibxbHA7ZbWAhVKQyYKHcN_AM4Q6AEIOjAF#v=onepage&q=egyptian%20ancient%20pronunciation%20mAA%20-%20see%2C%20watch&f=false ... pg 113</ref>... <br> ............................. ===== Sound Changes ===== Victor (with penultimate/initial stress: Víctor) is coarticulated and changed in colloquial Arabic into fuktur, buktur or buķțur. ⲔⲨⲢⲒⲖⲖOⲤ (Κύριλλος) is pronounced krullus. ⲈⲠⲒⲤⲔOⲠOⲤ (επίσκοπος) is sometimes spelled ⲈⲠOⲤⲔOⲠOⲤ and pronounced <aboskobōs>. ϨⲈⲢⲈⲦⲒⲔOⲤ (αιρετικός) - heretic, is transcribed as ''harțūķi'' in Arabic.<br> Victoria is pronounced ''fakturya''/''faktūrya''. ⲂⲀⲤⲒⲖⲒOⲤ <basalyōs>, ⲠⲒⲤⲦⲀⲨⲢOⲤ <basțawrōs>, ΦⲒⲖOⲐⲈOⲤ <faltawōs> and telephone <talafōn>, telegraph <tallaġrāf>, television <talafazyōn>. == Stress-Tone == Egyptian appears to have had a distinct stress pattern culminating in various vocalizations if stress is relocated (according to Coptic spellings- one must thus adduce that this also occurred in the earlier phases of the language<ref>Some scholars, for example Helmut Satzinger believe accent was in "free variation" in the earlier phases of the Egyptian language: FOLIA ORIENTALIA vol 49 2012, On Egyptian Participles and Nomina Agentis by Helmut Satzinger pg 473.</ref>). First we'll go into some identifiable stress rules:<ref>https://copticsounds.files.wordpress.com/2012/10/ishak-emile-maher-the-phonetics-and-phonology-of-the-bohairic-dialect-of-coptice280a6-d-phil-thesis-university-of-oxford-1975-volume-2.pdf</ref> : 1.) If the ultimate syllable is long (i,e., CV́C or CVCC) then that syllable is always prominent. :: * ⲠⲈϤϪⲰⲘ (CVC-CV́C) - his book :: * ϮⲚⲀⲈⲢϨⲰⲂ (CV-CV-CVC-CV̄C) - I shall do work :: * ϮⲚⲀⲂⲰⲖ (CV-CV-CV̄C) - I shall lose :: * ϮⲚⲀⲂOⲖϤ (CV-CV-CV́CC) - I shall lose it : 2.) Words of which the ultimate syllable is not long have for the most part the penultimate syllable prominent :: * ⲢⲰⲘⲈ (CV́-CV) - man :: * ⲤOⲖⲤⲈⲖ (CV́C-CVC) - to comfort :: * ⲀϤϨⲒⲤⲈ (CVC-CV́-CV) - he became tired/toiled :: * ⲀϤϮⲠⲀϨⲢⲈ (CVC-CV-CV́C-CV) - he gave drugs; he healed : 3.) When both the penultimate and antepenultimate syllables are short, then the antepenultimate syllable is prominent (this appears more be to in response to Greek and foreign loan words); :: * ⲂⲀ́ⲠⲦⲒζⲈ > βαπτίζειν - baptize :: * Ⲁ́ⲤⲠⲀζⲈ > άσπάςεσφαι - greet; kiss :: * ⲤⲨ́ⲚⲀζⲈ (CV́-CV-CV) > συναγειν - gather; bring together :: * ⲤⲔÓⲢⲀⲔⲒⲢ ((CV)C-CV́-CV-CVC) - steep place; slope ::: However, it is not uncommon for the penultimate syllable to be prominent. : 4.) Moreover sometimes the stress falls on the syllabic consonant, but only if it is a sonorant consonant. The sonorant consonants are b , l , m , n , r , and the glide w.<ref>EGYPTIAN LANGUAGE: PHONETIC SYSTEM AND PRONUNCIATION II (written by Luigi Tripani)</ref> Though most elementary stems in Egyptian are going to have stress on the penultimate syllable (that is second to last syllable). There are instances where a change of stress occurs and will be discussed below: : 5.) In monosyllabic words augmented by suffixing another short syllable, the prominence does not shift,i.e., :: * (Ⲉ)ⲒⲰ́Ⲧ - father > ⲒÓϮ / ⲒÓⲦⲈ - fathers :: * ⲠⲈ́ - sky > ⲠⲎ́ⲨⲈ > skies :: * ⲂⲰ́Ⲗ - loosen > ⲂÓⲖⲦⲈⲚ - loosen us ::: But if the suffixed syllable is long the prominence is shifted according to rule #1 above, to the long syllable,i.e., ::: * ⲤÓⲚ - brother > ⲤⲚⲎ́OⲨ - brothers ::: * ϨⲰ́Ⲃ - thing > ϨⲂⲎ́OⲨⲒ - things : 6.) Prominence shifts on suffixation in words with the penultimate syllable prominent according to the afore-cited rules. Thus, :: a) If the suffix is a consonant, which will make the ultimate syllable long, the prominence will shift to that syllable. ::: * ⲤÓⲖⲤⲈⲖ (CV́C-CVC) - to comfort > ⲤⲈⲖⲤⲰ́ⲖⲔ (CVC-CV̄CC) - to comfort thee :: b) If the suffix is a short syllable the prominence will shift to the new penultimate position in the word, i.e., ::: * ⲀϤⲂÓⲢⲂⲈⲢ (CVC-CV́C-CVC) - he threw down ::: * ⲀϤⲂⲈⲢⲂⲰ́ⲢⲦⲈⲚ (CVC-CVC-CV̄C-CVC) - he threw us down ::: * ⲀϤⲂⲈⲢⲂⲰ́ⲢOⲨ (CVC-CVC-CV̄C-CV / CV̄) - he threw them down :: c) If a suffix of the v(c) type is added to a word where a penultimate open syllable is prominent, the prominence will not shift from this same syllable since it becomes long through closure, /i/ being elided in open non-prominent syllables, ::: * ⲀϤⲤⲰ́ⲦⲈⲘ (CVC-CV̄-CVC) - he heard > ⲀϤⲤÓⲐⲘⲈϤ (CVC-CV́C-CVC) - he heard him > ⲀϤⲤÓⲐⲘOⲨ (CVC-CV́C-CVC) - he heard them : 7.) When two or more words are placed closely together to form a compound noun or a word group of a looser kind, the prominence falls on the last word only according to the afore-cited rules and the long vowel of the preceding words is shortened (more on this rule in the section below). Here's some examples: :: * ⲢⲘ̄ⲢⲀⲔÓⲦⲈ (CVC-CV-CV́-CV) - man of Alexandria ::: Similarly, in a rapidly pronounced sentence, the prominence falls on the last word only, ::: * ⲀⲘⲎⲚ ⲈⲤⲈ́ϢⲰⲠⲒ (amin asašōbi) - Amen, it will befall Below I have provided some generalized rules in connection with ''compound nouns'' which was mentioned under rule #6 as well as nouns with suffixes and prefixes: In the case of a nominal object, the addition of the object directly to the verb causes the tone to pass from the verb to the object,<br> Ⲁ.Ϥ.ϩⲈTB.Π.ⲢⲰⲘⲈ - we might call this object the 'tonal object'. However, when the object is a pronoun, it does not itself receive the tone, but rather follows the stressed syllable in the pronominal form of the verb, e.g<br> Ⲁ.Ϥ.ⲔOTB.Ϥ - It might be described as the 'post-tonal object', but in view of the fact that some verbs, owing to the loss of original consonants, do show a tonal stress on some suffix endings, e.g<br> ⲘⲈCⲦⲰ.Ⲕ - To hate thee<br> CⲀϩⲰ.Ϥ - To set him up, etc<br> A better name would be "direct suffix object", e.g<br> Ⲁ.Ⲛ.ⲢⲰⲘⲈ ⲘⲈPⲈ.Π.ⲔⲀⲔⲈ Ⲛ.ϩOYO Ⲉ.Ⲛ.OYOⲈⲒⲚ - Men loved darkness more than light<br> Ⲁ.Ϥ.NOϪ.Ϥ.Ⲉ.ⲠⲈ.ϢⲦⲈⲔO - He cast him into prison <ref>pg 19 http://bibletranslation.ws/down/Plumley_Coptic_Grammar.pdf</ref> <br> When two or more words are placed closely together to form a compound noun or group, the tone falls on the last word only and the formative vowel of the preceding word or words shortens; e.g<br> ϩOY-ⲘⲒCE - birthday (from ϩOOY - day and ⲘICⲈ - to give birth to)<br> ⲠⲈⲒ.PⲰⲘE - this man (from ⲠⲀⲒ - this and PⲰⲘⲈ - man)<br> CKPKP.Π.KOT - to revolve the wheel (from CKOPKP - To roll and Π.KOT - the wheel)<br> Plumley <ref>pgs 50-51 http://bibletranslation.ws/down/Plumley_Coptic_Grammar.pdf</ref> mentions, "the older forms of the language show that, apart from some verbs mentioned above, originally the direct object— either tonal object or direct suffix object— was the normal usage with all tenses".<br> James P. Allen <ref>pgs 167-168 ''James P. Allen'', Middle Egyptian: An Introduction to the Language and Culture of Hieroglyphs 2nd Edition</ref> mentions, The rule of Egyptian word order is, '''VsdoSOA''' (Verb, subject pronoun, dative (ex, n - of), object pronoun, Subject, Object, Adverbs and prepositional phrases) - capital letters refer to nouns, and small letters refer to pronouns. Pronominal datives (d) and objects (o) are separate words but were probably pronounced together with the verb without a separate stress of their own. Thus,<br> rdjt n.f t-ḥ<u>d</u> (giving him white-bread) probably had two stresses, ''rdjt-n.f'' and ''t-ḥ<u>d</u>'', just like in English, GIVing-him WHITE-bread.<br> rdjt.k n.j (n)syt.k (your giving me your kingship) probably had one stress on ''rdjt.k-n.j'' and ''(n)syt.k'', just like in English, your-GIVing-me your-KINGship.<br> jrt n.f st (to do it for him) probably had only one stress, just like in English, to DO it for him.<br> Nominal subjects, objects, and datives, on the other hand, tend to be stressed separately:<br> rdjt mn<u>t</u>w tɜwj n jtj (MONtu’s GIVing the-Two-LANDS to-the-SIRE).<br> It is also to be noted, in relation to subject / object additions, that in Egyptian the subject and object are behind the verb and in Coptic the subject is in front of the verb:<br> '''Egyptian'''<br> prt sm - the emerging of the sem-priest<br> prt.s - it's emerging<br> '''Coptic'''<br> Ⲡ.PⲰⲘE CⲰⲦⲘ - the man hears<br> Ϥ.CⲰⲦⲘ - he hears<br> And the direct object follows the subject in Egyptian, and in Coptic the direct object follows the verb:<br> '''Egyptian'''<br> jrt jst jɜkb - Isis's making mourning<br> <u>t</u>zt.j jb.j - my lifting up my heart<br> rdjt.f wj m ḥɜt <u>h</u>rdw.f - his placing me in front of his children<br> '''Coptic'''<br> Ϯ.NⲀ.ⲂⲰⲖ - I will loose => †.NⲀ.ⲂⲖ.TH<u>Y</u>TN - I will loose you [uses the pronomial form]<br> Ⲁ.Ϥ.ϩⲈⲦⲂ.Ⲡ.PⲰⲘⲈ - He killed the man [with a nominal object the construct form is used]<br> This results in different stress patterns between Egyptian and Coptic spelling.<br> Antonio Loprieno<ref>Loprieno, Antonio. A Linguistic Introduction pg 89</ref> mentions: 'Infinitives may be used in construct or in pronominal state followed by the subject (with intransitive verbs: pr.t=k /'pirtvk/ "your going forth") or by the object (with transitive verbs: s<u>d</u>m=f /'saɟmvf/ "to hear him"; the subject is introduced in this case by the preposition jn).<br> <br> Loprieno also gives an example of a noun augmented to a nominal verb stem (which he terms ''emphatic/nominal'' [like its Semitic equivalent ''iparras''] - this pattern follows the ''a-Type'' vocalization)<ref>Loprieno, Antonio. A Linguistic Introduction pg 79</ref>. This inflectional verb pattern is basically identical to that of the Egyptian infinitive:<br> s<u>d</u>m zɜ=j ~ saɟam'zi:ʀaj - my son listens<br> jrr=s ~ ja'ra:rvs - she does<br> ==== Pre-Late Egyptian Construct Form ==== In order to render a shift in stress-tone orthographically for Pre-Late Egyptian, I have chosen to use an [[w:Acute accent | acute accent]] which goes on top of the [[w:Secondary stress | secondary stressed vowel]]. For example:<br> prt sm => pǎrat^{^OEg} / pǐrit^{^MEg} + sǎm (pírit-sǎm) - the emerging of the sm-priest<br> === Anaptyxis <ref>A majority of the examples are taken from: https://copticsounds.files.wordpress.com/2012/10/ishak-emile-maher-the-phonetics-and-phonology-of-the-bohairic-dialect-of-coptice280a6-d-phil-thesis-university-of-oxford-1975-volume-2.pdf ... pg 703.</ref>=== Anaptyxis is the insertion of a vowel between two consonants in pronunciation, as in filim for film. Both Egyptian Arabic and Coptic have consonant clusters. In Coptic these are more common in Sahidic dialect, while in Bohairic dialect the syllabic centres are plainly marked by vowels, which have been preserved by a different manner of speaking.<br> Sahidic Coptic has combinations that have in them an unusual number of consonants, i.e.,<br> : ⲚⲦⲚⲚⲦⲘⲚⲦϨⲖⲖO - and we bring old age<br> In such forms the very short vowels had disappeared leaving syllabic consonants in their place (this is in general possible only with nasals and liquids /m, n, r, l/). Division into syllables was indicated by placing a stroke over the consonant that served in place of a vowel as such a sonorous centre. The sound indicated by the stroke extended backward or forward so as to include in part a preceding or succeeding letter that belonged to the same syllable. With these strokes or dashes the combination read;<br> : Ⲛ̄ Ⲧ͡Ⲛ Ⲛ̄ ⲦⲘ̄Ⲛ̄Ⲧ̄ Ϩ͡ⲖⲖO -- and was pronounced n-tn-n-tmnt-hl-loo<br> Every vowelless syllable is 'marked by such a stroke. In Bohairic the same combination would be written:<br> : ̀ⲚⲦⲈⲚⲈⲚⲐⲘⲈⲦϧⲈⲖⲖO -- where the division into syllables is plainly marked by vowels.<br> This stroke may be regarded therefore as a representation of a 'helping' or anaptictic vowel. The site of anaptyxis<ref>Anaptyxis is used here to cover initial vocalisation which is elsewhere styled prothesis and prosthesis.</ref> depends upon whether the consonant clusters are initial, medial or final in the word. ==== Initial Consonant Clusters ==== Initial CCV syllable is very common in Coptic (writing), i.e., : ^SB ⲘⲔⲀϨ - be painful ... ⲘϪⲰⲖ - onion ... ⲚⲔOⲦ - sleep ... ⲚϢOⲦ - be hard ... ⲤⲘⲎ - voice ... ⲤⲘOⲨ - bless ... ⲤⲚⲀⲨ - two ... ϢϢⲎⲚ - tree, ect ... In the Cairene and Bohairic dialects an initial CCV syllable cannot stand (in pronunciation), and a prothetic vowel is added at the beginning of the form. This is usually represented in Coptic by a line over the first consonant, or by the addition of an anaptyctic vowel between C1 and C2. The same also occurs in the Sahidic dialect, but to a lesser extent, i.e.,<br> : ^Bohairic ΦⲚOⲨϮ /ebnōsi/ - God, ⲘⲚOⲨⲦ /emnūt/ - sexton, ⲘⲚⲎ /emnī/ - there, ϢⲦOⲘ /išṭūm/ - damn, ϢⲐⲎⲚ /ištān/ - garment, ϢΦⲎⲢⲒ /ešbāri/ - wonder, ^Greek Κλήρος /eklīros/ - clergy Sometimes the anaptyctic vowel is so established to be indicated by the letter Ⲉ in orthographic variants, mostly in Bohairic,i. e.,<br> : ⲘⲔⲀϨ ~ ⲈⲘⲔⲀϨ - be painful, difficult : ⲘϨⲀⲨ ~ ⲈⲘϨⲀⲨ - tomb : ⲚⲔOⲦ ~ ⲈⲚⲔOⲦ - sleep : ϨⲖⲒ ~ ⲈϨⲖⲒ - anyone, anything : ϨⲢⲰⲦ ~ ⲈϨⲢⲰⲦ - wine-press ===== Examples of Anaptyctic Vowels between C1 and C2 ===== In Sahidic words, there appears to be instead a different set of regulations with initial CCV syllables<ref>Examples cited from here: https://www.jstor.org/stable/pdf/592389.pdf?refreqid=excelsior%3Ade6ddb0346d871efb2374e7dc1ae4606</ref> (it also seems that Bohairic adopts this vocalization as well, but it appears to have existed exclusively with Sahidic):<br> : It should be observed that ̀Ⲛ appears as ''ěn'' in ^Bohairic but in ^Sahiric as ''ni'', i.e.,<br> :: ̀ⲚϦⲎⲦϤ - enḫītf^{^Bahairic}, niḫădaf^{^Sahidic} but, when, however, it is followed by a second /n/, this is not the case, i.e.,<br> ::: ̀ⲚⲚⲒⲢⲰⲘⲒ /ennirōmi/^{B & S}. In the same way ̀Ⲙ = ěm in both pronunciations, ̀ⲘⲠⲈ /empē/^{^Bahairic}, /embǎ/^{^Sahidic} : The same can be said of other words which also had a stroke above the first consonant:<br> :: Ⲡ̄ⲤⲀϪⲒ /epsǎži/^{^Bohairic}, /bisǎgi/^{^Sahidic} :: This also occurred even if there was a vowel after the first consonant:<br> ::: Ⲧ̄ⲀⲢⲬⲎ /etǎr<u>h</u>i/^{^Bahairic}, /diǎr<u>h</u>i/^{^Sahidic} Here's some examples without the stroke above the first consonant:<br> : ⲀϪⲠⲒ /'ağbiyya/^{^{^Bohairic}} /ğibiyya/^{^Sahidic} - horologium : ϪⲠ^{^Sahidic} (ϪⲈⲠ) ~ ⲀϪⲠ^{^{S & B}} - hour : Κράμβη > ⲔⲢⲀⲘⲂⲈ ~ ΓⲢⲀⲘⲂⲎ /krumb/^{^{Sahidic Egyptian Arabic}}, /kurumb/^{Egyptian Arabic} - cabbage : φάρια ~ όφάρια > ⲠⲤⲀⲢⲒⲀ /bisarya/^{^{Egyptian Arabic}}, /basarya/, /bsarya/ & /ebsarya/^{^{Sahidic Egyptian Arabic}} - small fish In addition to the anaptyxis between C1 and C2 note the elision of the vowel between C2 and C3 in these three examples:<br> : φραγέλλιον > ΦⲢⲀΓΓⲈⲖⲖⲒOⲚ /firgilla/^{^{Sahidic Egyptian Arabic}} - whip of cords<br> : φλεγμα > ΦⲖⲈГⲘⲀ /balgam/^{^{Egyptian Arabic}} - phlegm : τραπεζα > ⲦⲢⲀⲠⲈΖⲀ /ṭarabēza/^{^{Egyptian Arabic}}, /ṭirbēza/^{^{Sahidic Egyptian Arabic}} - table Some more examples (which are town names):<br> : ⲐⲘOⲨⲒ /timay/^{^Bohairic} : ΦⲒOⲘ /fyum/^{^Bohairic}, /fayyūm/^{^Sahidic} : ⲤⲒOⲰⲨⲦ^{^Bohairic}, ⲤⲒOOⲨⲦ^{^Sahidic} (sɜwty, sywt^{^Dem}) > /asyūṭ/ -- written also ⲤⲒOOⲨⲈ /syūṭ/ or /siyūṭ/ : ϢⲘⲒⲚ^{^{B & S}}, ⲬⲘⲒⲚ^{^Sahidic} /a<u>h</u>mīm/, pronounced also /e<u>h</u>mīm, <u>h</u>mīm, <u>h</u>imīm/<br> : ⲠⲢⲠⲈ^{^Sahidic} /(il)-birba/^{^{General Arabic}} Sometimes the anaptyctic vowel is established and registered in orthographic variants with the vowel letter, usually Ⲉ:<br> : ⲈⲘϢⲒⲢ, ⲘϢⲒⲢ^{^{B & S}} > ⲘⲈϢⲒⲢ^{^Sahidic}, ⲘⲈⲬⲒⲢ^{^{S & B}}, ⲘⲒϢⲎⲢ^{^Fayyumic} - the 6th Coptic Month : ⲀϪⲠ^{^{S & B}} ϪⲈⲠ^{^Sahidic} - hour Here's an example of Greek letter Ψ-ps being broken up, which gives us an insight of the biliterals of the hieroglyphics: <br> : ΨⲀⲦⲈ > ⲠⲈⲤⲀⲦⲈ pronounced /bsāda/ or /bisāda/ - a proper name ==== Medial Consonant Clusters: (-C1C2C3-) ==== Medial clusters of three successive consonants can be pronounced in Sahidic Coptic and in the Arabic dialects of the same geographical region without any anaptyctic vowel, for example (using Egyptian Arabic):<br> : /kattfu/, 'bind (m.sg.) him!' : /fattšu/, 'inspect (m.sg.) him!' : /mattnu/, 'make (m.sg.) it (m.) tighter!' : /sakktu/, 'make (m.sg.) him keep quiet!' : /yištmu/, 'he insults him' : /yilbdow/, 'they stand' : /yimsku/, 'he holds it (m.) /him' : /yumdġow/, 'they shew' : /yirdmow/, 'they hail dust' In Coptic we have:<br> : Sahidic Coptic :: ⲦⲈⲔⲘ<u>Ⲛ̄ⲦϪ</u>OⲈⲒⲤ - thy lordship :: Ⲙ<u>Ⲛ̄ⲦⲤ</u>OⲚ - brotherhood :: Ⲙ<u>Ⲛ̄ⲦⲢ</u>ⲰⲘⲈ - humanity :: Ⲙ<u>Ⲛ̄ⲦⲔ</u>OⲨⲒ - smallness :: Ⲙ<u>Ⲛ̄ⲦϨ</u>ⲈⲂⲢⲀⲒOⲤ - Hebrew (language) :: Ⲙ<u>Ⲛ̄ⲦⲤ</u>ⲰⲦⲠ - choice :: Ⲙ<u>Ⲛ̄ⲦⲤⲚ</u>OⲨⲤ - twelve :: ϪOⲨ<u>ⲦϢⲘ</u>ⲎⲚ - twenty-eight :: ϢⲘ<u>Ⲛ̄ⲦϢ</u>Ⲉ - three hundred :: OⲨⲀ<u>ⲘⲤⲚ</u>OϤ - blood thirsty man (lit: eater of blood) :: The proper name ⲀⲚⲦⲢⲈⲤ < Ανδρεος is, still used in Upper Egypt and pronounced /andris/. : Bohairic Coptic :: OⲨO<u>ⲢⲠⲦ</u>ⲈⲚ - to send us :: O<u>ⲘⲔⲦ</u>ⲈⲚ - to swallow us :: O<u>ⲘⲤⲦ</u>ⲈⲚ - to dip us :: ϤⲈ<u>ⲘⲠϢ</u>Ⲁ - he/it deserves, pronounced /fambša/<br> :: Ⲛ̄ⲐⲈ /ïntʰě/ ... Ⲛ̄ϤϢⲰⲠⲈ /ïnfšōpe/ :: ⲚΓⲔⲰ /ingko/ ... Ⲛ̄ΓⲚⲀϨⲘⲚ̄ /ïngnǎhmin/ In the Bohairic dialect of Coptic and in many of the Arabic dialects of Lower Egypt, and to a lesser extent in Sahidic dialect of Coptic and the EA. dialects of Upper Egypt, medial or final clusters of three consonants may not occur and an anaptyctic vowel is introduced usually between the second and third consonants, i.e.,<br> : Egyptian Arabic (Sahidic) /sakktu/ > EA (Bohairic) /sakkitu/, 'make (m.sg.) him keep quiet!'<br> : Egyptian Arabic (Sahidic) /fahhmu/ > EA (Bohairic) /fahhimu/, 'let (m.sg.) him understand!'<br> : EA(S) /ğibbtu/ EA(B) /gibbitu/, 'his cloak' : EA(S) /yimsku/ EA(B) /yimsiku/, 'holds it (m.)' : EA(S) /yuntru/ EA(B) /yunturu/, 'throws it (m.) away' : EA(S) /bintha/ EA(B) /bintaha/, 'her daughter' : EA(S) /ibnha/ EA(B) /ibnaha/, 'her son' : Bohairic Coptic :: ϢOⲖϨⲤ /šǒlh^əs/ - corpse :: ⲬⲢⲈⲘⲦⲤ /krɛ́mdis/ - smoke : Sahidic :: ⲘⲀⲤⲦϤ /mistef/ - to give birth to him :: Ⲛ̄ϦⲎⲦϤ /niḫādaf/ - in it, Bohairic, in this example, (erroneously) has<ref>https://www.jstor.org/stable/pdf/592389.pdf?refreqid=excelsior%3Ade6ddb0346d871efb2374e7dc1ae4606 ... pg 9</ref>: /enḫātf/ :: Also the proper name ⲀⲚⲦⲢⲈⲤ < Ανδρεος, used in Upper Egypt, is pronounced either /andris/ or /andaris/ The Coptic CV̄CC pattern of verbs (model: ΦⲰⲢϢ^{^B}, ⲠⲰⲢϢ^{^S}) has the pronominal form CVCC (ΦOⲢϢ^{^B}, ⲠOⲢϢ^{^S}). On the affixation of a consonantal suffix, the resulting cluster is pronounced with a helping vowel between C2 and C3, e.g.,<br> : ΦOⲢϢϤ^{^B} /foršif/ ... ⲠOⲢϢϤ^{^S} /boršif/ - spread it : ⲤOⲐⲘⲈϤ^{^B} - to hear him To this pattern ( CV̄-CVC > CVC-C= ) belongs by far the largest number of Coptic verbs, over 200 in all.<br> Exceptions to this usual site of the anaptycptic vowel between C2 and C3 are due either to a tendency to preserve the distinctiveness of a word's main formative syllables or when a monogram letter represents both C2 and C3 together, i.e.,<br> : Bohairic Coptic:<br> :: ⲚⲈⲚΨⲨⲬⲎ /nanebsīka/ - our souls :: ⲚⲈϤⲤⲚOϤ /bafisnōf/ - his blood Notice that the Coptic verbal pattern ( CVC-CVC > CVC-CV̄C= ) does not clash with the above-mentioned second rule,i.e.,<br> : ⲤOⲖⲤⲖ^{^S} - to console > ⲤⲖⲤⲰⲖ(Ⲉ)Ϥ - to console him... In these examples, the long vowel of the pronominal form, being in an apparently closed penultimate syllable, does not shorten, the syllable being pronounced as if it were in fact an open syllable, thus: ⲤⲖ̄ⲤⲰⲖ- > <u>ⲤⲖ</u>-ⲤⲰ-<u>ⲖϤ</u> and this is how it is realized in Sahidic, but in Bohairic it is a closed syllable, the long vowel being shortened despite the orthography.In this case therefore the long vowel denotes only the prominent syllable and not vowel quantity. ==== Final Consonant Clusters ==== Final clusters of two consonants are common in Coptic (writing), as well in Egyptian Arabic and in contrast to many Levantine and Iraqi dialects<ref> Coleman (1996 et seq.) has argued that, for the Berber data, syllables with alleged consonantal nuclei actually contain a very reduced schwa, it is uncertain if this also existed in Coptic ... http://faculty.georgetown.edu/rtk8/Kramer%20Root%20and%20Pattern%20Morphology%20in%20Coptic.pdf ..pg 400 </ref>,<br> : Egyptian Arabic :: /fatk/, 'hole in clothes' :: /<u>h</u>atm/, 'seal (nn.)' (ḫtm - to seal) :: /nafs/, 'soul' ... etc. : Coptic :: ⲘⲀⲤϤ /masf/ - to give birth to him :: Ⲉ̀ⲢⲀⲦϤ /arǎdf/ - to his foot/feet :: ⲈϪⲠ /ağb/ - hour :: ⲈⲒⲈⲂⲦ /yabt/ - east In Coptic, final clusters of three consonants can occur without any anaptyctic vowel, e.g.,<br> :: ⲬⲢⲈⲘⲦⲤ^{^B} /kramds/ - smoke :: ⲔⲖΨ /kïlps/^{^S} - blow The same also with clusters of, three consonants resulting from pronouncing two successive words quickly (though this does not occur in the Cairo dialect),i.e.,<br> : Egyptian Arabic (Sahidic) :: /gult-lu/ - I said to him :: /katabt-lak/ - I wrote to you : Bohairic Coptic :: ϧⲈⲚ ΦⲢⲀⲚ ⲘⲠϬⲤ̄, pronounced in Upper Egypt as /<u>h</u>an bran ɛmbšoys/ - in the name of the Lord :: ⲈⲂOⲖϧⲈⲚ ⲦΦⲨⲖⲎ in Upper Egypt as /awǒl <u>h</u>andfilɛ/ - from the tribe Sometimes even with elision of a vowel, e.g.,<br> :: ⲀⲤⲘⲒⲤⲒ Ⲙ̀ⲘOϤ /asmīsmmof/ == Notes == The instability of vowel qualities within the Egyptian language may have had two main explanations:<br> * Some type of language contact or multilingual borrowings with a Nilo-Saharan language (or more than one as well as any other unrelated Afroasiatic language/s) in Egyptian's pre-history. Nilo-Saharan languages utilize distinct linguistic features such as [[w:Advanced and retracted tongue root|advanced retracted tongue root (ATR/RTR)]] as well as [[w:Vowel harmony|vowel harmony]] and [[w:Tone (linguistics)|tone/pitch]] possibly explaining some of the vowel inconsistencies in Egyptian. These linguistic features were lost in Egyptian Pre-history but remnants may have still existed (for example relocation of ''tone-stress'' occasionally changes vowel qualities in Coptic- this is not ''too'' common in most Afroasiatic languages (other than Hebrew) but is reminiscent of Nilo-Saharan ''pitch-tone relocation'' and/or ''vowel harmony''). This also seems to be the case with Cushitic languages which also have Nilo-Saharan/Niger-Congo sub-phylum characteristics.<br> * The infamous [[w:Canaanite shift|Canaanite shift]] contributed to a ''total'' reorganization of vowel qualities before the turn of the century.<br> .... ..... ..... ...... [[Category:Pre-Late Egyptian Reconstruction|{{SUBPAGENAME}}]] 2icwbmqbqtibhzp11o2a6gxah3uvlyk 0 221576 2844898 2830397 2026-11-08T21:58:01Z Jtneill 10242 + References 2844898 wikitext text/x-wiki {{Motivation and emotion/Lectures|Lecture 4: Extrinsic motivation and psychological needs|fourth}} {{Motivation and emotion/Lectures/Complete}} <!-- {{Motivation and emotion/Lectures/In development}} --> <!-- {{Motivation and emotion/Lectures/Complete}} --> ==Overview== [[File:Carrot and stick motivation.svg|200px|right]] This lecture discusses human motivation in terms of: * a taxonomy of motivation which includes intrinsic and extrinsic motivation * psychological needs according to [[self-determination theory]] (autonomy, competence, relatedness) Key question: What is the "secret sauce" for unlocking "intrinsic motivation"? Take-home messages: * Intrinsic motivation usually produces better outcomes than extrinsic motivation * The more complex the task, the more important is intrinsic motivation * Intrinsic motivation is fostered by conditions which support autonomy, competence, and relatedness ==Outline== Extrinsic motivation and internalisation * Extrinsic motivation * Incentives and consequences * Hidden costs of reward * Cognitive evaluation theory * Intrinsic motivation * Types of extrinsic motivation * Internalisation and integration * Motivating others on uninteresting activities Psychological needs * Psychological needs * Need frustration * Autonomy * Competence * Relatedness ==Autonomy support== One of the most powerful ways to engage someone's intrinsic motivation is to support their experience of the basic psychological need for autonomy (see Table 1 for examples). '''Table 1'''. Autonomy-Supportive Alternatives to Controlling Behaviours (based on Reeve (2024, p. 98) {| class="wikitable" style="margin: auto;" |- ! Instead of trying to motivate<br>with these controlling behaviours ... ! ! ... consider these alternative<br>autonomy-supportive behaviours |- | Take only your own perspective | → | Take the other person's perspective |- | Use extrinsic incentives | → | Invite the other to pursue their interests |- | Give directives without explanations | → | Provide meaningful rationales for requests |- | Encourage pursuit of extrinsic goals | → | Encourage pursuit of intrinsic goals |- | Induce guilt, shame, or self-worth concerns | → | Support personal valuing and volitional internalisation |- | Counter or try to change negative feelings | → | Acknowledge and accept negative feelings |- | Use controlling language | → | Use non-pressuring, invitational language |- | Pressure for immediate compliance | → | Display patience; allow time for self-initiation |} ==Multimedia== * [http://www.youtube.com/watch?v=u6XAPnuFjJc The surprising science of motivation] (Dan Pink, RSA Animate, YouTube) (10:47 min): What are the psychological ingredients for harnessing motivation in the workplace? External motivators such as money are useful, up to a point, but beyond that the work needs to allow for autonomy and be meaningful to engage intrinsic motivation. * [http://www.youtube.com/watch?v=5aH2Ppjpcho&t=594 What makes us feel good about our work?] (Dan Ariely, TEDx talk, 2013) (10:32 min): Describes several eye-opening experiments which manipulate the way simple tasks are conducted and measure how this affects people's performance and reactions. The amount of control and effort we exert influences how much we value the outcome. ==Readings== * Chapter 6: Extrinsic motivation and internalization ([[Motivation and emotion/Readings/Textbooks/Reeve/2024|Reeve, 2024]]) * Chapter 5: Psychological needs ([[Motivation and emotion/Readings/Textbooks/Reeve/2024|Reeve, 2024]]) ==Slides== * [https://docs.google.com/presentation/d/1kHoSY6Lzd-Shr8v23F6gYvxGCr6-neN8B4_sqyKAKZM/edit?usp=sharing Extrinsic motivation and internalisation] (Google Slides) * [https://docs.google.com/presentation/d/1HOjJDhp7GDQdbUMqZ6zp_vXVlgGjjXUW90nJps3__Mc/edit?usp=sharing Psychological needs] (Google Slides) <!-- ** [https://www.slideshare.net/jtneill/extrinsic-motivation-79269759 Extrinsic motivation] (Slideshare) ** [https://www.slideshare.net/jtneill/psychological-needs-79269786 Psychological needs] (Slideshare) 2016 and pre * [http://www.slideshare.net/jtneill/psychological-and-social-needs Lecture slides] (Slideshare) * Handouts ** [[Media:Motivation and Emotion - Lecture 04 - Extrinsic motivation & psychological needs 6slidesperpage.pdf|Download 6 slides to a page]]: [[File:Motivation and Emotion - Lecture 04 - Extrinsic motivation & psychological needs 6slidesperpage.pdf|100px]] ** [[Media:Motivation and Emotion - Lecture 04 - Extrinsic motivation & psychological needs 3slidesperpage.pdf|Download 3 slides to a page]]: [[File:Motivation and Emotion - Lecture 04 - Extrinsic motivation & psychological needs 3slidesperpage.pdf|100px]] --> ==See also== ;Wikipedia * [[w:Carrot and stick|Carrot and stick]] * [[w:Cognitive evaluation theory|Cognitive evaluation theory]] ;Wikiversity * [[Extrinsic motivation]] * [[/Images/]] * [[Intrinsic motivation]] * [[Psychological needs]] * [[Self-determination theory]] ;Lectures * [[{{#titleparts:{{PAGENAME}}|2}}/Brain and physiological needs|Brain and physiological needs]] (Previous lecture) * [[{{#titleparts:{{PAGENAME}}|2}}/Goals and mindsets|Goals and mindsets]] (Next lecture) ;Tutorial * [[Motivation and emotion/Tutorials/Psychological needs|Psychological needs]] (Tutorial) ==Recording== * [https://au-lti.bbcollab.com/recording/7963127abebe472db4c7ea15946b9d3e Lecture 4] (2026)<!-- * [https://au-lti.bbcollab.com/recording/2a93b1df5ee7476baf0e060cd2daf8a5 Lecture 4] (2025) * [https://au-lti.bbcollab.com/recording/33a40d59c9014ef38f6e7b767bf1bd49 Lecture 4] (2024) * [https://au-lti.bbcollab.com/recording/95fc9e2ff7fe45148b7b1a8145816bcc Lecture 4] (2023) * [https://au-lti.bbcollab.com/recording/73c5999c38034ba99b4d56a6a875977f Lecture 4] (2022) * [https://au-lti.bbcollab.com/recording/1989aa67804d4be1a303929130a548dc Lecture 4] (2021) --> ==References== {{Hanging indent|1= Alderfer, C. P. (1969). An empirical test of a new theory of human needs. ''Organizational Behavior & Human Performance'', ''4''(2), 142–175. https://doi.org/10.1016/0030-5073(69)90004-X }} ==External links== * [https://www.ted.com/talks/ayelet_fishbach_how_to_set_the_right_goals_and_stay_motivated How to set the right goals and stay motivated] (Ayelet Fishbach, TEDxChicago, October 2023, 17:04 mins) * [https://selfdeterminationtheory.org/meta-theory-the-organismic-viewpoint/ Meta-theory: The organismic viewpoint] (selfdeterminationtheory.org){{Motivation and emotion/Lectures/Navigation}} [[Category:Motivation and emotion/Lectures/Extrinsic motivation and psychological needs]] o9lfmndzbnmv12vewi7o2ugn3mtaq68 3 250786 2844959 2844208 2026-11-09T10:34:28Z MediaWiki message delivery 983498 /* Tech News: 2026-46 */ new section 2844959 wikitext text/x-wiki == First Message Posting == Update Talk on Wikiversity [[User:Bnhassin|Bnhassin]] ([[User talk:Bnhassin|discuss]] • [[Special:Contributions/Bnhassin|contribs]]) 21:04, 29 June 2019 (UTC) == Update Sandbox User == == Posting to sandbox == Update Sandbox on Wikiversity [[User:Bnhassin/sandbox]] ([[User talk:Bnhassin|discuss]] • [[Special:Contributions/Bnhassin|contribs]])[[User:Bnhassin|Bnhassin]] ([[User talk:Bnhassin|discuss]] • [[Special:Contributions/Bnhassin|contribs]]) 11:04, 25 October 2020 (UTC) == [[m:Special:MyLanguage/Tech/News/2020/50|Tech News: 2020-50]] == <section begin="technews-2020-W50"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2020/50|Translations]] are available. '''Recent changes''' * You can now put pages on your watchlist for a limited period of time. Some wikis already had this function. [https://meta.wikimedia.org/wiki/Community_Tech/Watchlist_Expiry][https://www.mediawiki.org/wiki/Help:Watchlist_expiry] '''Changes later this week''' * Information from Wikidata that is used on a wiki page can be shown in recent changes and watchlists on a Wikimedia wiki. To see this you need to turn on showing Wikidata edits in your watchlist in the preferences. Changes to the Wikidata description in the language of a Wikimedia wiki will then be shown in recent changes and watchlists. This will not show edits to languages that are not relevant to your wiki. [https://lists.wikimedia.org/pipermail/wikidata/2020-November/014402.html][https://phabricator.wikimedia.org/T191831] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.21|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2020-12-08|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2020-12-09|en}}. It will be on all wikis from {{#time:j xg|2020-12-10|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * You can vote on proposals in the [[m:Special:MyLanguage/Community Wishlist Survey 2021|Community Wishlist Survey]] between 8 December and 21 December. The survey decides what the [[m:Community Tech|Community Tech team]] will work on. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2020/50|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2020-W50"/> 16:15, 7 December 2020 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=20754641 --> == [[m:Special:MyLanguage/Tech/News/2020/51|Tech News: 2020-51]] == <section begin="technews-2020-W51"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2020/51|Translations]] are available. '''Recent changes''' * There is a [[mw:Wikipedia for KaiOS|Wikipedia app]] for [[:w:en:KaiOS|KaiOS]] phones. It was released in India in September. It can now be downloaded in other countries too. [https://diff.wikimedia.org/2020/12/10/growing-wikipedias-reach-with-an-app-for-kaios-feature-phones/] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.22|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2020-12-15|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2020-12-16|en}}. It will be on all wikis from {{#time:j xg|2020-12-17|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2020/51|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2020-W51"/> 21:34, 14 December 2020 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=20803489 --> == [[m:Special:MyLanguage/Tech/News/2020/52|Tech News: 2020-52]] == <section begin="technews-2020-W52"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2020/52|Translations]] are available. '''Tech News''' * Because of the [[w:en:Christmas and holiday season|holidays]] the next issue of Tech News will be sent out on 11 January 2021. '''Recent changes''' * The <code><nowiki>{{citation needed}}</nowiki></code> template shows when a statement in a Wikipedia article needs a source. If you click on it when you edit with the visual editor there is a popup that explains this. Now it can also show the reason and when it was added. [https://phabricator.wikimedia.org/T270107] '''Changes later this week''' * There is no new MediaWiki version this week or next week. '''Future changes''' * You can [[m:WMDE Technical Wishes/Geoinformation/Ideas|propose and discuss]] what technical improvements should be done for geographic information. This could be coordinates, maps or other related things. * Some wikis use [[mw:Writing systems/LanguageConverter|LanguageConverter]] to switch between writing systems or variants of a language. This can only be done for the entire page. There will be a <code><nowiki><langconvert></nowiki></code> tag that can convert a piece of text on a page. [https://phabricator.wikimedia.org/T263082] * Oversighters and stewards can hide entries in [[Special:AbuseLog|Special:AbuseLog]]. They can soon hide multiple entries at once using checkboxes. This works like hiding normal edits. It will happen in early January. [https://phabricator.wikimedia.org/T260904] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2020/52|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2020-W52"/> 20:54, 21 December 2020 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=20833836 --> == [[m:Special:MyLanguage/Tech/News/2021/02|Tech News: 2021-02]] == <section begin="technews-2021-W02"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/02|Translations]] are available. '''Recent changes''' * You can choose to be reminded when you have not added an edit summary. This can be done in your preferences. This could conflict with the [[:w:en:CAPTCHA|CAPTCHA]]. This has now been fixed. [https://phabricator.wikimedia.org/T12729] * You can link to specific log entries. You can get these links for example by clicking the timestamps in the log. Until now, such links to private log entries showed no entry even if you had permission to view private log entries. The links now show the entry. [https://phabricator.wikimedia.org/T269761] * Admins can use the [[:mw:Special:MyLanguage/Extension:AbuseFilter|abuse filter tool]] to automatically prevent bad edits. Three changes happened last week: ** The filter editing interface now shows syntax errors while you type. This is similar to JavaScript pages. It also shows a warning for regular expressions that match the empty string. New warnings will be added later. [https://phabricator.wikimedia.org/T187686] ** [[m:Special:MyLanguage/Meta:Oversighters|Oversighters]] can now hide multiple filter log entries at once using checkboxes on [[Special:AbuseLog]]. This is how the usual revision deletion works. [https://phabricator.wikimedia.org/T260904] ** When a filter matches too many actions after it has been changed it is "throttled". The most powerful actions are disabled. This is to avoid many editors getting blocked when an administrator made a mistake. The administrator will now get a notification about this "throttle". * [[File:Octicons-tools.svg|15px|link=|Advanced item]] There is a new tool to [https://skins.wmflabs.org/?#/add build new skins]. You can also [https://skins.wmflabs.org/?#/ see] existing [[mw:Special:MyLanguage/Manual:Skins|skins]]. You can [[mw:User talk:Jdlrobson|give feedback]]. [https://lists.wikimedia.org/pipermail/wikitech-l/2020-December/094130.html] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Bots using the API no longer watch pages automatically based on account preferences. Setting the <code>watchlist</code> to <code>watch</code> will still work. This is to reduce the size of the watchlist data in the database. [https://phabricator.wikimedia.org/T258108] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[mw:Special:MyLanguage/Extension:Scribunto|Scribunto's]] [[:mw:Extension:Scribunto/Lua reference manual#File metadata|file metadata]] now includes length. [https://phabricator.wikimedia.org/T209679] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[:w:en:CSS|CSS]] and [[:w:en:JavaScript|JavaScript]] code pages now have link anchors to [https://patchdemo.wmflabs.org/wikis/40e4795d4448b55a6d8c46ff414bcf78/w/index.php/MediaWiki:En.js#L-125 line numbers]. You can use wikilinks like [[:w:en:MediaWiki:Common.js#L-50]]. [https://phabricator.wikimedia.org/T29531] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] There was a [[mw:MediaWiki 1.36/wmf.25|new version]] of MediaWiki last week. You can read [[mw:MediaWiki 1.36/wmf.25/Changelog|a detailed log]] of all 763 changes. Most of them are very small and will not affect you. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.26|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-01-12|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-01-13|en}}. It will be on all wikis from {{#time:j xg|2021-01-14|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/02|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W02"/> 15:42, 11 January 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=20950047 --> == [[m:Special:MyLanguage/Tech/News/2021/03|Tech News: 2021-03]] == <section begin="technews-2021-W03"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/03|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.27|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-01-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-01-20|en}}. It will be on all wikis from {{#time:j xg|2021-01-21|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * The [[mw:Special:MyLanguage/Growth|Growth team]] plans to add features to [[mw:Special:MyLanguage/Growth/Personalized first day/Newcomer tasks/Experiment analysis, November 2020|get more visitors to edit]] to more Wikipedias. You can help [https://translatewiki.net/w/i.php?title=Special:Translate&group=ext-growthexperiments&language=&filter=&action=translate translating the interface]. * You will be able to read but not to edit Wikimedia Commons for a short time on [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210126T07 {{#time:j xg|2021-01-26|en}} at 07:00 (UTC)]. [https://phabricator.wikimedia.org/T271791] * [[m:Special:MyLanguage/MassMessage|MassMessage]] posts could be automatically timestamped in the future. This is because MassMessage senders can now send pages using MassMessage. Pages are more difficult to sign. If there are times when a MassMessage post should not be timestamped you can [[phab:T270435|let the developers know]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/03|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W03"/> 16:10, 18 January 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=20974628 --> == [[m:Special:MyLanguage/Tech/News/2021/04|Tech News: 2021-04]] == <section begin="technews-2021-W04"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/04|Translations]] are available. '''Problems''' * You will be able to read but not to edit Wikimedia Commons for a short time on [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210126T07 {{#time:j xg|2021-01-26|en}} at 07:00 (UTC)]. You will not be able to read or edit [[:wikitech:Main Page|Wikitech]] for a short time on [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210128T09 {{#time:j xg|2021-01-28|en}} at 09:00 (UTC)]. [https://phabricator.wikimedia.org/T271791][https://phabricator.wikimedia.org/T272388] '''Changes later this week''' * [[m:WMDE Technical Wishes/Bracket Matching|Bracket matching]] will be added to the [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror]] syntax highlighter on the first wikis. The first wikis are German and Catalan Wikipedia and maybe other Wikimedia wikis. This will happen on 27 January. [https://phabricator.wikimedia.org/T270238] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.28|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-01-26|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-01-27|en}}. It will be on all wikis from {{#time:j xg|2021-01-28|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/04|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W04"/> 18:31, 25 January 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21007423 --> == [[m:Special:MyLanguage/Tech/News/2021/05|Tech News: 2021-05]] == <section begin="technews-2021-W05"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/05|Translations]] are available. '''Problems''' * [[:w:en:IPv6|IPv6 addresses]] were written in lowercase letters in diffs. This caused dead links since [[Special:Contributions|Special:Contributions]] only accepted uppercase letters for the IPs. This has been fixed. [https://phabricator.wikimedia.org/T272225] '''Changes later this week''' * You can soon use Wikidata to link to pages on the multilingual Wikisource. [https://phabricator.wikimedia.org/T138332] * Often editors use a "non-breaking space" to make a gap between two items when reading but still show them together. This can be used to avoid a line break. You will now be able to add new ones via the special character tool in the 2010, 2017, and visual editors. The character will be shown in the visual editor as a space with a grey background. [https://phabricator.wikimedia.org/T70429][https://phabricator.wikimedia.org/T96666] * [[File:Octicons-tools.svg|15px|link=| Advanced item]] Wikis use [[mw:Special:MyLanguage/Extension:AbuseFilter|abuse filters]] to stop bad edits being made. Filter maintainers can now use syntax like <code>1.2.3.4 - 1.2.3.55</code> as well as the <code>1.2.3.4/27</code> syntax for IP ranges. [https://phabricator.wikimedia.org/T218074] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.29|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-02-02|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-02-03|en}}. It will be on all wikis from {{#time:j xg|2021-02-04|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * [[mw:Skin:Minerva Neue|Minerva]] is the skin Wikimedia wikis use for mobile traffic. When a page is protected and you can't edit it you can normally read the source wikicode. This doesn't work on Minerva on mobile devices. This is being fixed. Some text might overlap. This is because your community needs to update [[MediaWiki:Protectedpagetext|MediaWiki:Protectedpagetext]] to work on mobile. You can [[phab:T208827|read more]]. [https://www.mediawiki.org/wiki/Recommendations_for_mobile_friendly_articles_on_Wikimedia_wikis#Inline_styles_should_not_use_properties_that_impact_sizing_and_positioning][https://www.mediawiki.org/wiki/Recommendations_for_mobile_friendly_articles_on_Wikimedia_wikis#Avoid_tables_for_anything_except_data] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[:wikitech:Portal:Cloud VPS|Cloud VPS]] and [[:wikitech:Portal:Toolforge|Toolforge]] will change the IP address they use to contact the wikis. The new IP address will be <code>185.15.56.1</code>. This will happen on February 8. You can [[:wikitech:News/CloudVPS NAT wikis|read more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/05|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W05"/> 22:38, 1 February 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21033195 --> == [[m:Special:MyLanguage/Tech/News/2021/06|Tech News: 2021-06]] == <section begin="technews-2021-W06"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/06|Translations]] are available. '''Recent changes''' * The [[mw:Special:MyLanguage/Wikimedia Apps|Wikipedia app]] for Android now has watchlists and talk pages in the app. [https://play.google.com/store/apps/details?id=org.wikipedia] '''Changes later this week''' * You can see edits to chosen pages on [[Special:Watchlist|Special:Watchlist]]. You can add pages to your watchlist on every wiki you like. The [[:mw:Special:MyLanguage/Extension:GlobalWatchlist|GlobalWatchlist]] extension will come to Meta on 11 February. There you can see entries on watched pages on different wikis on the same page. The new watchlist will be found on [[m:Special:GlobalWatchlist|Special:GlobalWatchlist]] on Meta. You can choose which wikis to watch and other preferences on [[m:Special:GlobalWatchlistSettings|Special:GlobalWatchlistSettings]] on Meta. You can watch up to five wikis. [https://phabricator.wikimedia.org/T260862] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.30|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-02-09|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-02-10|en}}. It will be on all wikis from {{#time:j xg|2021-02-11|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * When admins [[mw:Special:MyLanguage/Help:Protecting and unprotecting pages|protect]] pages the form will use the [[mw:UX standardization|OOUI look]]. [[Special:Import|Special:Import]] will also get the new look. This will make them easier to use on mobile phones. [https://phabricator.wikimedia.org/T235424][https://phabricator.wikimedia.org/T108792] * Some services will not work for a short period of time from 07:00 UTC on 17 February. There might be problems with new [[m:Special:MyLanguage/Wikimedia URL Shortener|short links]], new translations, new notifications, adding new items to your [[mw:Reading/Reading Lists|reading lists]] or recording [[:w:en:Email#Tracking of sent mail|email bounces]]. This is because of database maintenance. [https://phabricator.wikimedia.org/T273758] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[m:Tech/News/2021/05|Last week]] Tech News reported that the IP address [[:wikitech:Portal:Cloud VPS|Cloud VPS]] and [[:wikitech:Portal:Toolforge|Toolforge]] use to contact the wikis will change on 8 February. This is delayed. It will happen later instead. [https://wikitech.wikimedia.org/wiki/News/CloudVPS_NAT_wikis] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/06|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W06"/> 17:42, 8 February 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21082948 --> == [[m:Special:MyLanguage/Tech/News/2021/07|Tech News: 2021-07]] == <section begin="technews-2021-W07"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/07|Translations]] are available. '''Problems''' * There were problems with recent versions of MediaWiki. Because the updates caused problems the developers rolled back to an earlier version. Some updates and new functions will come later than planned. [https://lists.wikimedia.org/pipermail/wikitech-l/2021-February/094255.html][https://lists.wikimedia.org/pipermail/wikitech-l/2021-February/094271.html] * Some services will not work for a short period of time from 07:00 UTC on 17 February. There might be problems with new [[m:Special:MyLanguage/Wikimedia URL Shortener|short links]], new translations, new notifications, adding new items to your [[mw:Reading/Reading Lists|reading lists]] or recording [[:w:en:Email#Tracking of sent mail|email bounces]]. This is because of database maintenance. [https://phabricator.wikimedia.org/T273758] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.31|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-02-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-02-17|en}}. It will be on all wikis from {{#time:j xg|2021-02-18|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/07|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W07"/> 17:56, 15 February 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21105437 --> == [[m:Special:MyLanguage/Tech/News/2021/08|Tech News: 2021-08]] == <div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/08|Translations]] are available. '''Recent changes''' * The visual editor will now use [[:c:Commons:Structured data/Media search|MediaSearch]] to find images. You can search for images on Commons in the visual editor when you are looking for illustrations. This is to help editors find better images. [https://phabricator.wikimedia.org/T259896] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[mw:Special:MyLanguage/Extension:SyntaxHighlight|syntax highlighter]] now works with more languages: [[:w:en:Futhark (programming language)|Futhark]], [[:w:en:Graphviz|Graphviz]]/[[:w:en:DOT (graph description language)|DOT]], CDDL and AMDGPU. [https://phabricator.wikimedia.org/T274741] '''Problems''' * Editing a [[mw:Special:MyLanguage/Extension:EasyTimeline|timeline]] might have removed all text from it. This was because of a bug and has been fixed. You might need to edit the timeline again for it to show properly. [https://phabricator.wikimedia.org/T274822] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.32|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-02-23|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-02-24|en}}. It will be on all wikis from {{#time:j xg|2021-02-25|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] There is a [[:m:Wikimedia Rust developers user group|user group]] for developers and users interested in working on Wikimedia wikis with the [[:w:en:Rust (programming language)|Rust programming language]]. You can join or tell others who want to make your wiki better in the future. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/08|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div> ---- 00:17, 23 February 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21134058 --> == [[m:Special:MyLanguage/Tech/News/2021/09|Tech News: 2021-09]] == <div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/09|Translations]] are available. '''Recent changes''' * Wikis using the [[mw:Special:MyLanguage/Growth/Feature summary|Growth team tools]] can now show the name of a newcomer's mentor anywhere [[mw:Special:MyLanguage/Help:Growth/Mentorship/Integrating_mentorship|through a magic word]]. This can be used for welcome messages or userboxes. * A new version of the [[c:Special:MyLanguage/Commons:VideoCutTool|VideoCutTool]] is now available. It enables cropping, trimming, audio disabling, and rotating video content. It is being created as part of the developer outreach programs. '''Problems''' * There was a problem with the [[mw:Special:MyLanguage/Manual:Job queue|job queue]]. This meant some functions did not save changes and mass messages were delayed. This did not affect wiki edits. [https://phabricator.wikimedia.org/T275437] * Some editors may not be logged in to their accounts automatically in the latest versions of Firefox and Safari. [https://phabricator.wikimedia.org/T226797] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.33|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-03-02|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-03-03|en}}. It will be on all wikis from {{#time:j xg|2021-03-04|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/09|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div> ---- 19:08, 1 March 2021 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21161722 --> == [[m:Special:MyLanguage/Tech/News/2021/10|Tech News: 2021-10]] == <section begin="technews-2021-W10"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/10|Translations]] are available. '''Recent changes''' * [[mw:Special:MyLanguage/Content translation/Section translation|Section translation]] now works on Bengali Wikipedia. It helps mobile editors translate sections of articles. It will come to more wikis later. The first focus is active wikis with a smaller number of articles. You can [https://sx.wmflabs.org/index.php/Main_Page test it] and [[mw:Talk:Content translation/Section translation|leave feedback]]. * [[mw:Special:MyLanguage/Help:Extension:FlaggedRevs|Flagged revisions]] now give admins the review right. [https://phabricator.wikimedia.org/T275293] * When someone links to a Wikipedia article on Twitter this will now show a preview of the article. [https://phabricator.wikimedia.org/T276185] '''Problems''' * Many graphs have [[:w:en:JavaScript|JavaScript]] errors. Graph editors can check their graphs in their browser's developer console after editing. [https://phabricator.wikimedia.org/T275833] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.34|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-03-09|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-03-10|en}}. It will be on all wikis from {{#time:j xg|2021-03-11|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). * The [[mw:Talk pages project/New discussion|New Discussion]] tool will soon be a new [[mw:Special:MyLanguage/Extension:DiscussionTools|discussion tools]] beta feature for on most Wikipedias. The goal is to make it easier to start new discussions. [https://phabricator.wikimedia.org/T275257] '''Future changes''' * There will be a number of changes to make it easier to work with templates. Some will come to the first wikis in March. Other changes will come to the first wikis in June. This is both for those who use templates and those who create or maintain them. You can [[:m:WMDE Technical Wishes/Templates|read more]]. * [[m:WMDE Technical Wishes/ReferencePreviews|Reference Previews]] will become a default feature on some wikis on 17 March. They will share a setting with [[mw:Page Previews|Page Previews]]. If you prefer the Reference Tooltips or Navigation-Popups gadget you can keep using them. If so Reference Previews won't be shown. [https://phabricator.wikimedia.org/T271206][https://meta.wikimedia.org/wiki/Talk:WMDE_Technical_Wishes/ReferencePreviews] * New JavaScript-based functions will not work in [[:w:en:Internet Explorer 11|Internet Explorer 11]]. This is because Internet Explorer is an old browser that doesn't work with how JavaScript is written today. Everything that works in Internet Explorer 11 today will continue working in Internet Explorer for now. You can [[mw:Compatibility/IE11|read more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/10|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W10"/> 17:51, 8 March 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21175593 --> == [[m:Special:MyLanguage/Tech/News/2021/11|Tech News: 2021-11]] == <section begin="technews-2021-W11"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/11|Translations]] are available. '''Recent changes''' * Wikis that are part of the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|desktop improvements]] project can now use a new [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Features/Search|search function]]. The desktop improvements and the new search will come to more wikis later. You can also [[mw:Reading/Web/Desktop Improvements#Deployment plan and timeline|test it early]]. * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Editors who put up banners or change site-wide [[:w:en:JavaScript|JavaScript]] code should use the [https://grafana.wikimedia.org/d/000000566/overview?viewPanel=16&orgId=1 client error graph] to see that their changes has not caused problems. You can [https://diff.wikimedia.org/2021/03/08/sailing-steady%e2%80%8a-%e2%80%8ahow-you-can-help-keep-wikimedia-sites-error-free read more]. [https://phabricator.wikimedia.org/T276296] '''Problems''' * Due to [[phab:T276968|database issues]] the [https://meta.wikimedia.beta.wmflabs.org Wikimedia Beta Cluster] was read-only for over a day. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.34|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-03-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-03-17|en}}. It will be on all wikis from {{#time:j xg|2021-03-18|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * You can add a [[:w:en:Newline|newline]] or [[:w:en:Carriage return|carriage return]] character to a custom signature if you use a template. There is a proposal to not allow them in the future. This is because they can cause formatting problems. [https://www.mediawiki.org/wiki/New_requirements_for_user_signatures#Additional_proposal_(2021)][https://phabricator.wikimedia.org/T272322] * You will be able to read but not edit [[phab:T276899|12 wikis]] for a short period of time on [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210323T06 {{#time:j xg|2021-03-23|en}} at 06:00 (UTC)]. This could take 30 minutes but will probably be much faster. * [[File:Octicons-tools.svg|15px|link=|Advanced item]] You can use [https://quarry.wmflabs.org/ Quarry] for [[:w:en:SQL|SQL]] queries to the [[wikitech:Wiki replicas|Wiki Replicas]]. Cross-database <code>JOINS</code> will no longer work from 23 March. There will be a new field to specify the database to connect to. If you think this affects you and you need help you can [[phab:T268498|post on Phabricator]] or on [[wikitech:Talk:News/Wiki Replicas 2020 Redesign|Wikitech]]. [https://wikitech.wikimedia.org/wiki/PAWS PAWS] and other ways to do [[:w:en:SQL|SQL]] queries to the Wiki Replicas will be affected later. [https://wikitech.wikimedia.org/wiki/News/Wiki_Replicas_2020_Redesign] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/11|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W11"/> 23:22, 15 March 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21226057 --> == [[m:Special:MyLanguage/Tech/News/2021/12|Tech News: 2021-12]] == <section begin="technews-2021-W12"/><div class="plainlinks mw-content-ltr" lang="en" dir="ltr"><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/12|Translations]] are available. '''Recent changes''' * There is a [[mw:Wikipedia for KaiOS|Wikipedia app]] for [[:w:en:KaiOS|KaiOS]] phones. They don't have a touch screen so readers navigate with the phone keys. There is now a [https://wikimedia.github.io/wikipedia-kaios/sim.html simulator] so you can see what it looks like. * The [[mw:Special:MyLanguage/Talk pages project/Replying|reply tool]] and [[mw:Special:MyLanguage/Talk pages project/New discussion|new discussion tool]] are now available as the "{{int:discussiontools-preference-label}}" [[Special:Preferences#mw-prefsection-betafeatures|beta feature]] in almost all wikis except German Wikipedia. '''Problems''' * You will be able to read but not edit [[phab:T276899|twelve wikis]] for a short period of time on [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210323T06 {{#time:j xg|2021-03-23|{{PAGELANGUAGE}}}} at 06:00 (UTC)]. This can also affect password changes, logging in to new wikis, global renames and changing or confirming emails. This could take 30 minutes but will probably be much faster. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.36|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-03-23|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-03-24|en}}. It will be on all wikis from {{#time:j xg|2021-03-25|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). * [[:w:en:Syntax highlighting|Syntax highlighting]] colours will change to be easier to read. This will soon come to the [[phab:T276346|first wikis]]. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Improved_Color_Scheme_of_Syntax_Highlighting] '''Future changes''' * [[mw:Special:MyLanguage/Extension:FlaggedRevs|Flagged revisions]] will no longer have multiple tags like "tone" or "depth". It will also only have one tier. This was changed because very few wikis used these features and they make the tool difficult to maintain. [https://phabricator.wikimedia.org/T185664][https://phabricator.wikimedia.org/T277883] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Gadgets and user scripts can access variables about the current page in JavaScript. In 2015 this was moved from <code dir=ltr>wg*</code> to <code dir=ltr>mw.config</code>. <code dir=ltr>wg*</code> will soon no longer work. [https://phabricator.wikimedia.org/T72470] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]] • [[m:Special:MyLanguage/Tech/News#contribute|Contribute]] • [[m:Special:MyLanguage/Tech/News/2021/12|Translate]] • [[m:Tech|Get help]] • [[m:Talk:Tech/News|Give feedback]] • [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div></div> <section end="technews-2021-W12"/> 16:53, 22 March 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21244806 --> == [[m:Special:MyLanguage/Tech/News/2021/13|Tech News: 2021-13]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/13|Translations]] are available. '''Recent changes''' * Some very old [[:w:en:Web browser|web browsers]] [[:mw:Special:MyLanguage/Compatibility|don’t work]] well with the Wikimedia wikis. Some old code for browsers that used to be supported is being removed. This could cause issues in those browsers. [https://phabricator.wikimedia.org/T277803] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[:m:IRC/Channels#Raw_feeds|IRC recent changes feeds]] have been moved to a new server. Make sure all tools automatically reconnect to <code>irc.wikimedia.org</code> and not to the name of any specific server. Users should also consider switching to the more modern [[:wikitech:Event Platform/EventStreams|EventStreams]]. [https://phabricator.wikimedia.org/T224579] '''Problems''' * When you move a page that many editors have on their watchlist the history can be split. It might also not be possible to move it again for a while. This is because of a [[:w:en:Job queue|job queue]] problem. [https://phabricator.wikimedia.org/T278350] * Some translatable pages on Meta could not be edited. This was because of a bug in the translation tool. The new MediaWiki version was delayed because of problems like this. [https://phabricator.wikimedia.org/T278429][https://phabricator.wikimedia.org/T274940] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.37|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-03-30|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-03-31|en}}. It will be on all wikis from {{#time:j xg|2021-04-01|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/13|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 17:30, 29 March 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21267131 --> == [[m:Special:MyLanguage/Tech/News/2021/14|Tech News: 2021-14]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/14|Translations]] are available. '''Recent changes''' * Editors can collapse part of an article so you have to click on it to see it. When you click a link to a section inside collapsed content it will now expand to show the section. The browser will scroll down to the section. Previously such links didn't work unless you manually expanded the content first. [https://phabricator.wikimedia.org/T276741] '''Changes later this week''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[mw:Special:MyLanguage/Citoid|citoid]] [[:w:en:API|API]] will use for example <code>2010-12-XX</code> instead of <code>2010-12</code> for dates with a month but no days. This is because <code>2010-12</code> could be confused with <code>2010-2012</code> instead of <code>December 2010</code>. This is called level 1 instead of level 0 in the [https://www.loc.gov/standards/datetime/ Extended Date/Time Format]. [https://phabricator.wikimedia.org/T132308] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.36/wmf.38|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-04-06|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-04-07|en}}. It will be on all wikis from {{#time:j xg|2021-04-08|en}} ([[mw:MediaWiki 1.36/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[:wikitech:PAWS|PAWS]] can now connect to the new [[:wikitech:Wiki Replicas|Wiki Replicas]]. Cross-database <code>JOINS</code> will no longer work from 28 April. There is [[:wikitech:News/Wiki Replicas 2020 Redesign#How should I connect to databases in PAWS?|a new way to connect]] to the databases. Until 28 April both ways to connect to the databases will work. If you think this affects you and you need help you can post [[phab:T268498|on Phabricator]] or on [[wikitech:Talk:News/Wiki Replicas 2020 Redesign|Wikitech]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/14|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 19:41, 5 April 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21287348 --> == [[m:Special:MyLanguage/Tech/News/2021/16|Tech News: 2021-16]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/16|Translations]] are available. '''Recent changes''' * Email to the Wikimedia wikis are handled by groups of Wikimedia editors. These volunteer response teams now use [https://github.com/znuny/Znuny Znuny] instead of [[m:Special:MyLanguage/OTRS|OTRS]]. The functions and interface remain the same. The volunteer administrators will give more details about the next steps soon. [https://phabricator.wikimedia.org/T279303][https://phabricator.wikimedia.org/T275294] * If you use [[Mw:Special:MyLanguage/Extension:CodeMirror|syntax highlighting]], you can see line numbers in the 2010 and 2017 wikitext editors when editing templates. This is to make it easier to see line breaks or talk about specific lines. Line numbers will soon come to all namespaces. [https://phabricator.wikimedia.org/T267911][https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Line_Numbering][https://meta.wikimedia.org/wiki/Talk:WMDE_Technical_Wishes/Line_Numbering] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Because of a technical change there could be problems with gadgets and scripts that have an edit summary area that looks [https://phab.wmfusercontent.org/file/data/llvdqqnb5zpsfzylbqcg/PHID-FILE-25vs4qowibmtysl7cbml/Screen_Shot_2021-04-06_at_2.34.04_PM.png similar to this one]. If they look strange they should use <code>mw.loader.using('mediawiki.action.edit.styles')</code> to go back to how they looked before. [https://phabricator.wikimedia.org/T278898] * The [[mw:MediaWiki 1.37/wmf.1|latest version]] of MediaWiki came to the Wikimedia wikis last week. There was no Tech News issue last week. '''Changes later this week''' * There is no new MediaWiki version this week. '''Future changes''' * The user group <code>oversight</code> will be renamed <code>suppress</code>. This is for [[phab:T109327|technical reasons]]. This is the technical name. It doesn't affect what you call the editors with this user right on your wiki. This is planned to happen in two weeks. You can comment [[phab:T112147|in Phabricator]] if you have objections. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/16|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 16:48, 19 April 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21356080 --> == [[m:Special:MyLanguage/Tech/News/2021/17|Tech News: 2021-17]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/17|Translations]] are available. '''Recent changes''' * Templates have parameters that can have specific values. It is possible to suggest values for editors with [[mw:Special:MyLanguage/Extension:TemplateData|TemplateData]]. You can soon see them as a drop-down list in the visual editor. This is to help template users find the right values faster. [https://phabricator.wikimedia.org/T273857][https://meta.wikimedia.org/wiki/Special:MyLanguage/WMDE_Technical_Wishes/Suggested_values_for_template_parameters][https://meta.wikimedia.org/wiki/Talk:WMDE_Technical_Wishes/Suggested_values_for_template_parameters] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.3|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-04-27|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-04-28|en}}. It will be on all wikis from {{#time:j xg|2021-04-29|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/17|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 21:24, 26 April 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21391118 --> == [[m:Special:MyLanguage/Tech/News/2021/18|Tech News: 2021-18]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/18|Translations]] are available. '''Recent changes''' * [[w:en:Wikipedia:Twinkle|Twinkle]] is a gadget on English Wikipedia. It can help with maintenance and patrolling. It can [[m:Grants:Project/Rapid/SD0001/Twinkle localisation/Report|now be used on other wikis]]. You can get Twinkle on your wiki using the [https://github.com/wikimedia-gadgets/twinkle-starter twinkle-starter] GitHub repository. '''Problems''' * The [[mw:Special:MyLanguage/Content translation|content translation tool]] did not work for many articles for a little while. This was because of a bug. [https://phabricator.wikimedia.org/T281346] * Some things will not work for about a minute on 5 May. This will happen [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210505T0600 around 06:00 UTC]. This will affect the content translation tool and notifications among other things. This is because of an upgrade to avoid crashes. [https://phabricator.wikimedia.org/T281212] '''Changes later this week''' * [[mw:Special:MyLanguage/Help:Reference Previews|Reference Previews]] will become a default feature on a number of wikis on 5 May. This is later than planned because of some changes. You can use it without using [[mw:Special:MyLanguage/Page Previews|Page Previews]] if you want to. The earlier plan was to have the preference to use both or none. [https://phabricator.wikimedia.org/T271206][https://meta.wikimedia.org/wiki/Talk:WMDE_Technical_Wishes/ReferencePreviews] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.4|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-05-04|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-05-05|en}}. It will be on all wikis from {{#time:j xg|2021-05-06|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[:w:en:CSS|CSS]] classes <code dir=ltr>.error</code>, <code dir=ltr>.warning</code> and <code dir=ltr>.success</code> do not work for mobile readers if they have not been specifically defined on your wiki. From June they will not work for desktop readers. This can affect gadgets and templates. The classes can be defined in [[MediaWiki:Common.css]] or template styles instead. [https://phabricator.wikimedia.org/T280766] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/18|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 15:43, 3 May 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21418010 --> == [[m:Special:MyLanguage/Tech/News/2021/19|Tech News: 2021-19]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/19|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-05-11|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-05-12|en}}. It will be on all wikis from {{#time:j xg|2021-05-13|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * You can see what participants plan to work on at the online [[mw:Wikimedia Hackathon 2021|Wikimedia hackathon]] 22–23 May. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/19|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 15:10, 10 May 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21428676 --> == [[m:Special:MyLanguage/Tech/News/2021/20|Tech News: 2021-20]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/20|Translations]] are available. '''Recent changes''' * There is a new toolbar in [[mw:Talk pages project/Replying|the Reply tool]]. It works in the wikitext source mode. You can enable it in [[Special:Preferences#mw-htmlform-discussion|your preferences]]. [https://phabricator.wikimedia.org/T276608] [https://www.mediawiki.org/wiki/Talk_pages_project/Replying#13_May_2021] [https://www.mediawiki.org/wiki/Talk_pages_project/New_discussion#13_May_2021] * Wikimedia [https://lists.wikimedia.org/mailman/listinfo mailing lists] are being moved to [[:w:en:GNU Mailman|Mailman 3]]. This is a newer version. For the [[:w:en:Character encoding|character encoding]] to work it will change from <code>[[:w:en:UTF-8|UTF-8]]</code> to <code>utf8mb3</code>. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/IEYQ2HS3LZF2P3DAYMNZYQDGHWPVMTPY/][https://phabricator.wikimedia.org/T282621] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] An [[m:Special:MyLanguage/Tech/News/2021/14|earlier issue]] of Tech News said that the [[mw:Special:MyLanguage/Citoid|citoid]] [[:w:en:API|API]] would handle dates with a month but no days in a new way. This has been reverted for now. There needs to be more discussion of how it affects different wikis first. [https://phabricator.wikimedia.org/T132308] '''Changes later this week''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] <code>MediaWiki:Pageimages-blacklist</code> will be renamed <code>MediaWiki:Pageimages-denylist</code>. The list can be copied to the new name. It will happen on 19 May for some wikis and 20 May for some wikis. Most wikis don't use it. It lists images that should never be used as thumbnails for articles. [https://phabricator.wikimedia.org/T282626] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.6|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-05-18|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-05-19|en}}. It will be on all wikis from {{#time:j xg|2021-05-20|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/20|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 13:49, 17 May 2021 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21464279 --> == [[m:Special:MyLanguage/Tech/News/2021/21|Tech News: 2021-21]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/21|Translations]] are available. '''Recent changes''' * The Wikimedia movement has been using [[:m:Special:MyLanguage/IRC|IRC]] on a network called [[:w:en:Freenode|Freenode]]. There have been changes around who is in control of the network. The [[m:Special:MyLanguage/IRC/Group_Contacts|Wikimedia IRC Group Contacts]] have [[m:Special:Diff/21476411|decided]] to move to the new [[:w:en:Libera Chat|Libera Chat]] network instead. This is not a formal decision for the movement to move all channels but most Wikimedia IRC channels will probably leave Freenode. There is a [[:m:IRC/Migrating_to_Libera_Chat|migration guide]] and ongoing Wikimedia [[m:Wikimedia Forum#Freenode (IRC)|discussions about this]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-05-25|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-05-26|en}}. It will be on all wikis from {{#time:j xg|2021-05-27|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/21|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 17:07, 24 May 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21477606 --> == [[m:Special:MyLanguage/Tech/News/2021/22|Tech News: 2021-22]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/22|Translations]] are available. '''Problems''' * There was an issue on the Vector skin with the text size of categories and notices under the page title. It was fixed last Monday. [https://phabricator.wikimedia.org/T283206] '''Changes later this week''' * There is no new MediaWiki version this week. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/22|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 17:05, 31 May 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21516076 --> == [[m:Special:MyLanguage/Tech/News/2021/23|Tech News: 2021-23]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/23|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.9|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-06-08|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-06-09|en}}. It will be on all wikis from {{#time:j xg|2021-06-10|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * The Wikimedia movement uses [[:mw:Special:MyLanguage/Phabricator|Phabricator]] for technical tasks. This is where we collect technical suggestions, bugs and what developers are working on. The company behind Phabricator will stop working on it. This will not change anything for the Wikimedia movement now. It could lead to changes in the future. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/message/YAXOD46INJLAODYYIJUVQWOZFIV54VUI/][https://admin.phacility.com/phame/post/view/11/phacility_is_winding_down_operations/][https://phabricator.wikimedia.org/T283980] * Searching on Wikipedia will find more results in some languages. This is mainly true for when those who search do not use the correct [[:w:en:Diacritic|diacritics]] because they are not seen as necessary in that language. For example searching for <code>Bedusz</code> doesn't find <code>Będusz</code> on German Wikipedia. The character <code>ę</code> isn't used in German so many would write <code>e</code> instead. This will work better in the future in some languages. [https://phabricator.wikimedia.org/T219550] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[:w:en:Cross-site request forgery|CSRF token parameters]] in the [[:mw:Special:MyLanguage/API:Main page|action API]] were changed in 2014. The old parameters from before 2014 will stop working soon. This can affect bots, gadgets and user scripts that still use the old parameters. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/IMP43BNCI32C524O5YCUWMQYP4WVBQ2B/][https://phabricator.wikimedia.org/T280806] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/23|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 20:02, 7 June 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21551759 --> == [[m:Special:MyLanguage/Tech/News/2021/24|Tech News: 2021-24]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/24|Translations]] are available. '''Recent changes''' * Logged-in users on the mobile web can choose to use the [[:mw:Special:MyLanguage/Reading/Web/Advanced mobile contributions|advanced mobile mode]]. They now see categories in a similar way as users on desktop do. This means that some gadgets that have just been for desktop users could work for users of the mobile site too. If your wiki has such gadgets you could decide to turn them on for the mobile site too. Some gadgets probably need to be fixed to look good on mobile. [https://phabricator.wikimedia.org/T284763] * Language links on Wikidata now works for [[:oldwikisource:Main Page|multilingual Wikisource]]. [https://phabricator.wikimedia.org/T275958] '''Changes later this week''' * There is no new MediaWiki version this week. '''Future changes''' * In the future we [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation|can't show the IP]] of unregistered editors to everyone. This is because privacy regulations and norms have changed. There is now a rough draft of how [[m:IP Editing: Privacy Enhancement and Abuse Mitigation#Updates|showing the IP to those who need to see it]] could work. * German Wikipedia, English Wikivoyage and 29 smaller wikis will be read-only for a few minutes on 22 June. This is planned between 5:00 and 5:30 UTC. [https://phabricator.wikimedia.org/T284530] * All wikis will be read-only for a few minutes in the week of 28 June. More information will be published in Tech News later. It will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T281515][https://phabricator.wikimedia.org/T281209] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/24|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 20:26, 14 June 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21587625 --> == [[m:Special:MyLanguage/Tech/News/2021/25|Tech News: 2021-25]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/25|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The <code>otrs-member</code> group name is now <code>vrt-permissions</code>. This could affect abuse filters. [https://phabricator.wikimedia.org/T280615] '''Problems''' * You will be able to read but not edit German Wikipedia, English Wikivoyage and 29 smaller wikis for a few minutes on 22 June. This is planned between [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210623T0500 5:00 and 5:30 UTC]. [https://phabricator.wikimedia.org/T284530] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.11|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-06-22|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-06-23|en}}. It will be on all wikis from {{#time:j xg|2021-06-24|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/25|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 15:49, 21 June 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21593987 --> == [[m:Special:MyLanguage/Tech/News/2021/26|Tech News: 2021-26]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/26|Translations]] are available. '''Recent changes''' * Wikis with the [[mw:Special:MyLanguage/Growth|Growth features]] now can [[mw:Special:MyLanguage/Growth/Community configuration|configure Growth features directly on their wiki]]. This uses the new special page <code>Special:EditGrowthConfig</code>. [https://phabricator.wikimedia.org/T285423] * Wikisources have a new [[m:Special:MyLanguage/Community Tech/OCR Improvements|OCR tool]]. If you don't want to see the "extract text" button on Wikisource you can add <code>.ext-wikisource-ExtractTextWidget { display: none; }</code> to your [[Special:MyPage/common.css|common.css page]]. [https://phabricator.wikimedia.org/T285311] '''Problems''' *You will be able to read but not edit the Wikimedia wikis for a few minutes on 29 June. This is planned at [https://www.timeanddate.com/worldclock/fixedtime.html?iso=20210629T1400 14:00 UTC]. [https://phabricator.wikimedia.org/T281515][https://phabricator.wikimedia.org/T281209] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.12|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-06-29|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-06-30|en}}. It will be on all wikis from {{#time:j xg|2021-07-01|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * <code>Threshold for stub link formatting</code>, <code>thumbnail size</code> and <code>auto-number headings</code> can be set in preferences. They are expensive to maintain and few editors use them. The developers are planning to remove them. Removing them will make pages load faster. You can [[mw:Special:MyLanguage/User:SKim (WMF)/Performance Dependent User Preferences|read more and give feedback]]. * A toolbar will be added to the [[mw:Talk pages project/Replying|Reply tool]]'s wikitext source mode. This will make it easier to link to pages and to ping other users. [https://phabricator.wikimedia.org/T276609][https://www.mediawiki.org/wiki/Talk_pages_project/Replying#Status_updates] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/26|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 16:32, 28 June 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21653312 --> == [[m:Special:MyLanguage/Tech/News/2021/27|Tech News: 2021-27]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/27|Translations]] are available. '''Tech News''' * The next issue of Tech News will be sent out on 19 July. '''Recent changes''' * [[:wikidata:Q4063270|AutoWikiBrowser]] is a tool to make repetitive tasks easier. It now uses [[:w:en:JSON|JSON]]. <code>Wikipedia:AutoWikiBrowser/CheckPage</code> has moved to <code>Wikipedia:AutoWikiBrowser/CheckPageJSON</code> and <code>Wikipedia:AutoWikiBrowser/Config</code>. <code>Wikipedia:AutoWikiBrowser/CheckPage/Version</code> has moved to <code>Wikipedia:AutoWikiBrowser/CheckPage/VersionJSON</code>. The tool will eventually be configured on the wiki so that you don't have to wait until the new version to add templates or regular expression fixes. [https://phabricator.wikimedia.org/T241196] '''Problems''' * [[m:Special:MyLanguage/InternetArchiveBot|InternetArchiveBot]] helps saving online sources on some wikis. It adds them to [[:w:en:Wayback Machine|Wayback Machine]] and links to them there. This is so they don't disappear if the page that was linked to is removed. It currently has a problem with linking to the wrong date when it moves pages from <code>archive.is</code> to <code>web.archive.org</code>. [https://phabricator.wikimedia.org/T283432] '''Changes later this week''' * The tool to [[m:WMDE Technical Wishes/Finding and inserting templates|find, add and remove templates]] will be updated. This is to make it easier to find and use the right templates. It will come to the first wikis on 7 July. It will come to more wikis later this year. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Removing_a_template_from_a_page_using_the_VisualEditor][https://phabricator.wikimedia.org/T284553] * There is no new MediaWiki version this week. '''Future changes''' * Some Wikimedia wikis use [[m:Special:MyLanguage/Flagged Revisions|Flagged Revisions]] or pending changes. It hides edits from new and unregistered accounts for readers until they have been patrolled. The auto review action in Flagged Revisions will no longer be logged. All old logs of auto-review will be removed. This is because it creates a lot of logs that are not very useful. [https://phabricator.wikimedia.org/T285608] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/27|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 17:33, 5 July 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21694636 --> == [[m:Special:MyLanguage/Tech/News/2021/29|Tech News: 2021-29]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/29|Translations]] are available. '''Recent changes''' * The tool to [[m:WMDE Technical Wishes/Finding and inserting templates|find, add and remove templates]] was updated. This is to make it easier to find and use the right templates. It was supposed to come to the first wikis on 7 July. It was delayed to 12 July instead. It will come to more wikis later this year. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Removing_a_template_from_a_page_using_the_VisualEditor][https://phabricator.wikimedia.org/T284553] * [[Special:UnconnectedPages|Special:UnconnectedPages]] lists pages that are not connected to Wikidata. This helps you find pages that can be connected to Wikidata items. Some pages should not be connected to Wikidata. You can use the magic word <code><nowiki>__EXPECTED_UNCONNECTED_PAGE__</nowiki></code> on pages that should not be listed on the special page. [https://phabricator.wikimedia.org/T97577] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.15|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-07-20|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-07-21|en}}. It will be on all wikis from {{#time:j xg|2021-07-22|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] How media is structured in the [[:w:en:Parsing|parser's]] HTML output will soon change. This can affect bots, gadgets, user scripts and extensions. You can [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/L2UQJRHTFK5YG3IOZEC7JSLH2ZQNZRVU/ read more]. You can test it on [[:testwiki:Main Page|Testwiki]] or [[:test2wiki:Main Page|Testwiki 2]]. * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The parameters for how you obtain [[mw:API:Tokens|tokens]] in the MediaWiki API were changed in 2014. The old way will no longer work from 1 September. Scripts, bots and tools that use the parameters from before the 2014 change need to be updated. You can [[phab:T280806#7215377|read more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/29|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 15:31, 19 July 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21755027 --> == [[m:Special:MyLanguage/Tech/News/2021/30|Tech News: 2021-30]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/30|Translations]] are available. '''Recent changes''' * A [[mw:MediaWiki 1.37/wmf.14|new version]] of MediaWiki came to the Wikimedia wikis the week before last week. This was not in Tech News because there was no newsletter that week. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.16|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-07-27|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-07-28|en}}. It will be on all wikis from {{#time:j xg|2021-07-29|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * If you use the [[mw:Special:MyLanguage/Skin:MonoBook|Monobook skin]] you can choose to switch off [[:w:en:Responsive web design|responsive design]] on mobile. This will now work for more skins. If <code>{{int:monobook-responsive-label}}</code> is unticked you need to also untick the new [[Special:Preferences#mw-prefsection-rendering|preference]] <code>{{int:prefs-skin-responsive}}</code>. Otherwise it will stop working. Interface admins can automate this process on your wiki. You can [[phab:T285991|read more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/30|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 21:11, 26 July 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21771634 --> == [[m:Special:MyLanguage/Tech/News/2021/31|Tech News: 2021-31]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/31|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] If your wiki uses markup like <bdi lang="zxx" dir="ltr"><code><nowiki><div class="mw-content-ltr"></nowiki></code></bdi> or <bdi lang="zxx" dir="ltr"><code><nowiki><div class="mw-content-rtl"></nowiki></code></bdi> without the required <bdi lang="zxx" dir="ltr"><code>dir</code></bdi> attribute, then these will no longer work in 2 weeks. There is a short-term fix that can be added to your local wiki's Common.css page, which is explained at [[phab:T287701|T287701]]. From now on, all usages should include the full attributes, for example: <bdi lang="zxx" dir="ltr"><code><nowiki><div class="mw-content-ltr" dir="ltr" lang="en"></nowiki></code></bdi> or <bdi lang="zxx" dir="ltr"><code><nowiki><div class="mw-content-rtl" dir="rtl" lang="he"></nowiki></code></bdi>. This also applies to some other HTML tags, such as <code>span</code> or <code>code</code>. You can find existing examples on your wiki that need to be updated, using the instructions at [[phab:T287701|T287701]]. * Reminder: Wikimedia has [[m:Special:MyLanguage/IRC/Migrating to Libera Chat|migrated to the Libera Chat IRC network]], from the old Freenode network. Local documentation should be updated. '''Problems''' * Last week, all wikis had slow access or no access for 30 minutes. There was a problem with generating dynamic lists of articles on the Russian Wikinews, due to the bulk import of 200,000+ new articles over 3 days, which led to database problems. The problematic feature has been disabled on that wiki and developers are discussing if it can be fixed properly. [https://phabricator.wikimedia.org/T287380][https://wikitech.wikimedia.org/wiki/Incident_documentation/2021-07-26_ruwikinews_DynamicPageList] '''Changes later this week''' * When adding links to a page using [[mw:VisualEditor|VisualEditor]] or the [[mw:Special:MyLanguage/2017 wikitext editor|2017 wikitext editor]], [[mw:Special:MyLanguage/Extension:Disambiguator|disambiguation pages]] will now only appear at the bottom of search results. This is because users do not often want to link to disambiguation pages. [https://phabricator.wikimedia.org/T285510] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.17|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-08-03|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-08-04|en}}. It will be on all wikis from {{#time:j xg|2021-08-05|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * The [[mw:Wikimedia Apps/Team/Android|team of the Wikipedia app for Android]] is working on communication in the app. The developers are working on how to talk to other editors and get notifications. You can [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/Communication|read more]]. They are looking for users who want to [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/Communication/UsertestingJuly2021|test the plans]]. Any editor who has an Android phone and is willing to download the app can do this. * The [[Special:Preferences#mw-prefsection-betafeatures|Beta Feature]] for {{int:discussiontools-preference-label}} will be updated in the coming weeks. You will be able to [[mw:Talk pages project/Notifications|subscribe to individual sections]] on a talk page at more wikis. You can test this now by adding <code>?dtenable=1</code> to the end of the talk page's URL ([https://meta.wikimedia.org/wiki/Meta_talk:Sandbox?dtenable=1 example]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 20:47, 2 August 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21818289 --> == [[m:Special:MyLanguage/Tech/News/2021/32|Tech News: 2021-32]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/32|Translations]] are available. '''Problems''' * You can read but not edit 17 wikis for a few minutes on 10 August. This is planned at [https://zonestamp.toolforge.org/1628571650 05:00 UTC]. This is because of work on the database. [https://phabricator.wikimedia.org/T287449] '''Changes later this week''' * The [[wmania:Special:MyLanguage/2021:Hackathon|Wikimania Hackathon]] will take place remotely on 13 August, starting at 5:00 UTC, for 24 hours. You can participate in many ways. You can still propose projects and sessions. * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.18|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-08-10|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-08-11|en}}. It will be on all wikis from {{#time:j xg|2021-08-12|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The old CSS <bdi lang="zxx" dir="ltr"><code><nowiki><div class="visualClear"></div></nowiki></code></bdi> will not be supported after 12 August. Instead, templates and pages should use <bdi lang="zxx" dir="ltr"><code><nowiki><div style="clear:both;"></div></nowiki></code></bdi>. Please help to replace any existing uses on your wiki. There are global-search links available at [[phab:T287962|T287962]]. '''Future changes''' * [[m:Special:MyLanguage/The Wikipedia Library|The Wikipedia Library]] is a place for Wikipedia editors to get access to sources. There is an [[mw:Special:MyLanguage/Extension:TheWikipediaLibrary|extension]] which has a new function to tell users when they can take part in it. It will use notifications. It will start pinging the first users in September. It will ping more users later. [https://phabricator.wikimedia.org/T288070] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] [[w:en:Vue.js|Vue.js]] will be the [[w:en:JavaScript|JavaScript]] framework for MediaWiki in the future. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/SOZREBYR36PUNFZXMIUBVAIOQI4N7PDU/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 16:21, 9 August 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21856726 --> == [[m:Special:MyLanguage/Tech/News/2021/33|Tech News: 2021-33]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/33|Translations]] are available. '''Recent changes''' * You can add language links in the sidebar in the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|new Vector skin]] again. You do this by connecting the page to a Wikidata item. The new Vector skin has moved the language links but the new language selector cannot add language links yet. [https://phabricator.wikimedia.org/T287206] '''Problems''' * There was a problem on wikis which use the Translate extension. Translations were not updated or were replaced with the English text. The problems have been fixed. [https://phabricator.wikimedia.org/T288700][https://phabricator.wikimedia.org/T288683][https://phabricator.wikimedia.org/T288719] '''Changes later this week''' * A [[mw:Help:Tags|revision tag]] will soon be added to edits that add links to [[mw:Special:MyLanguage/Extension:Disambiguator|disambiguation pages]]. This is because these links are usually added by accident. The tag will allow editors to easily find the broken links and fix them. If your wiki does not like this feature, it can be [[mw:Help:Tags#Deleting a tag added by the software|hidden]]. [https://phabricator.wikimedia.org/T287549] *Would you like to help improve the information about tools? Would you like to attend or help organize a small virtual meetup for your community to discuss the list of tools? Please get in touch on the [[m:Toolhub/The Quality Signal Sessions|Toolhub Quality Signal Sessions]] talk page. We are also looking for feedback [[m:Talk:Toolhub/The Quality Signal Sessions#Discussion topic for "Quality Signal Sessions: The Tool Maintainers edition"|from tool maintainers]] on some specific questions. * In the past, edits to any page in your user talk space ignored your [[mw:Special:MyLanguage/Help:Notifications#mute|mute list]], e.g. sub-pages. Starting this week, this is only true for edits to your talk page. [https://phabricator.wikimedia.org/T288112] * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.19|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-08-17|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-08-18|en}}. It will be on all wikis from {{#time:j xg|2021-08-19|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 19:27, 16 August 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21889213 --> == [[m:Special:MyLanguage/Tech/News/2021/34|Tech News: 2021-34]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/34|Translations]] are available. '''Recent changes''' * The [[mw:Special:MyLanguage/Extension:Score|Score]] extension (<bdi lang="zxx" dir="ltr"><code><nowiki><score></nowiki></code></bdi> notation) has been re-enabled on public wikis and upgraded to a newer version. Some musical score functionality may no longer work because the extension is only enabled in "safe mode". The security issue has been fixed and an [[mw:Special:MyLanguage/Extension:Score/2021 security advisory|advisory published]]. '''Problems''' * You will be able to read but not edit [[phab:T289130|some wikis]] for a few minutes on {{#time:j xg|2021-08-25|en}}. This will happen around [https://zonestamp.toolforge.org/1629871217 06:00 UTC]. This is for database maintenance. During this time, operations on the CentralAuth will also not be possible. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.20|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-08-24|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-08-25|en}}. It will be on all wikis from {{#time:j xg|2021-08-26|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 21:58, 23 August 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21923254 --> == Read-only reminder == <section begin="MassMessage"/> A maintenance operation will be performed on [https://zonestamp.toolforge.org/1629871231 {{#time: l F d H:i e|2021-08-25T06:00|en}}]. It should only last for a few minutes. This will affect your wiki as well as 11 other wikis. During this time, publishing edits will not be possible. Also during this time, operations on the CentralAuth will not be possible (GlobalRenames, changing/confirming e-mail addresses, logging into new wikis, password changes). For more details about the operation and on all impacted services, please check [[phab:T289130|on Phabricator]]. A banner will be displayed 30 minutes before the operation. Please help your community to be aware of this maintenance operation. {{Int:Feedback-thanks-title}}<section end="MassMessage"/> 20:35, 24 August 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21927201 --> == [[m:Special:MyLanguage/Tech/News/2021/35|Tech News: 2021-35]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/35|Translations]] are available. '''Recent changes''' * Some musical score syntax no longer works and may needed to be updated, you can check [[:Category:{{MediaWiki:score-error-category}}]] on your wiki for a list of pages with errors. '''Problems''' * Musical scores were unable to render lyrics in some languages because of missing fonts. This has been fixed now. If your language would prefer a different font, please file a request in Phabricator. [https://phabricator.wikimedia.org/T289554] '''Changes later this week''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The parameters for how you obtain [[mw:API:Tokens|tokens]] in the MediaWiki API were changed in 2014. The old way will no longer work from 1 September. Scripts, bots and tools that use the parameters from before the 2014 change need to be updated. You can [[phab:T280806#7215377|read more]] about this. * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.21|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-08-31|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-09-01|en}}. It will be on all wikis from {{#time:j xg|2021-09-02|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). '''Future changes''' * You will be able to read but not edit [[phab:T289660|Commons]] for a few minutes on {{#time:j xg|2021-09-06|en}}. This will happen around [https://zonestamp.toolforge.org/1630818058 05:00 UTC]. This is for database maintenance. * All wikis will be read-only for a few minutes in the week of 13 September. More information will be published in Tech News later. It will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T287539] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 16:01, 30 August 2021 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21954810 --> == [[m:Special:MyLanguage/Tech/News/2021/36|Tech News: 2021-36]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/36|Translations]] are available. '''Recent changes''' * The wikis that have [[mw:Special:MyLanguage/Growth/Feature_summary|Growth features]] deployed have been part of A/B testing since deployment, in which some newcomers did not receive the new features. Now, all of the newcomers on 21 of the smallest of those wikis will be receiving the features. [https://phabricator.wikimedia.org/T289786] '''Changes later this week''' * There is no new MediaWiki version this week. '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] In 2017, the provided jQuery library was upgraded from version 1 to 3, with a compatibility layer. The migration will soon finish, to make the site load faster for everyone. If you maintain a gadget or user script, check if you have any JQMIGRATE errors and fix them, or they will break. [https://phabricator.wikimedia.org/T280944][https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/6Z2BVLOBBEC2QP4VV4KOOVQVE52P3HOP/] * Last year, the Portuguese Wikipedia community embarked on an experiment to make log-in compulsory for editing.  The [[m:IP Editing: Privacy Enhancement and Abuse Mitigation/Impact report for Login Required Experiment on Portuguese Wikipedia|impact report of this trial]] is ready. Moving forward, the Anti-Harassment Tools team is looking for projects that are willing to experiment with restricting IP editing on their wiki for a short-term experiment. [[m:IP Editing: Privacy Enhancement and Abuse Mitigation/Login Required Experiment|Learn more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 15:20, 6 September 2021 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=21981010 --> == [[m:Special:MyLanguage/Tech/News/2021/37|Tech News: 2021-37]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/37|Translations]] are available. '''Recent changes''' * 45 new Wikipedias now have access to the [[mw:Special:MyLanguage/Growth/Feature summary|Growth features]]. [https://phabricator.wikimedia.org/T289680] * [[mw:Special:MyLanguage/Growth/Deployment table|A majority of Wikipedias]] now have access to the Growth features. The Growth team [[mw:Special:MyLanguage/Growth/FAQ|has published an FAQ page]] about the features. This translatable FAQ covers the description of the features, how to use them, how to change the configuration, and more. '''Problems''' * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on 14 September. This is planned at [https://zonestamp.toolforge.org/1631628002 14:00 UTC]. [https://phabricator.wikimedia.org/T287539] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.37/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-09-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-09-15|en}}. It will be on all wikis from {{#time:j xg|2021-09-16|en}} ([[mw:MediaWiki 1.37/Roadmap|calendar]]). * Starting this week, Wikipedia in Italian will receive weekly software updates on Wednesdays. It used to receive the updates on Thursdays. Due to this change, bugs will be noticed and fixed sooner. [https://phabricator.wikimedia.org/T286664] * You can add language links in the sidebar in [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|the new Vector skin]] again. You do this by connecting the page to a Wikidata item. The new Vector skin has moved the language links but the new language selector cannot add language links yet. [https://phabricator.wikimedia.org/T287206] * The [[mw:Special:MyLanguage/Extension:SyntaxHighlight|syntax highlight]] tool marks up code with different colours. It now can highlight 23 new code languages. Additionally, <bdi lang="zxx" dir="ltr"><code>golang</code></bdi> can now be used as an alias for the [[d:Q37227|Go programming language]], and a special <bdi lang="zxx" dir="ltr"><code>output</code></bdi> mode has been added to show a program's output. [https://phabricator.wikimedia.org/T280117][https://gerrit.wikimedia.org/r/c/mediawiki/extensions/SyntaxHighlight_GeSHi/+/715277/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 15:35, 13 September 2021 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22009517 --> == [[m:Special:MyLanguage/Tech/News/2021/38|Tech News: 2021-38]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/38|Translations]] are available. '''Recent changes''' * Growth features are now deployed to almost all Wikipedias. [[phab:T290582|For the majority of small Wikipedias]], the features are only available for experienced users, to [[mw:Special:MyLanguage/Growth/FAQ#enable|test the features]] and [[mw:Special:MyLanguage/Growth/FAQ#config|configure them]]. Features will be available for newcomers starting on 20 September 2021. * MediaWiki had a feature that would highlight local links to short articles in a different style. Each user could pick the size at which "stubs" would be highlighted. This feature was very bad for performance, and following a consultation, has been removed. [https://phabricator.wikimedia.org/T284917] * A technical change was made to the MonoBook skin to allow for easier maintenance and upkeep. This has resulted in some minor changes to HTML that make MonoBook's HTML consistent with other skins. Efforts have been made to minimize the impact on editors, but please ping [[m:User:Jon (WMF)|Jon (WMF)]] on wiki or in [[phab:T290888|phabricator]] if any problems are reported. '''Problems''' * There was a problem with search last week. Many search requests did not work for 2 hours because of an accidental restart of the search servers. [https://wikitech.wikimedia.org/wiki/Incident_documentation/2021-09-13_cirrussearch_restart] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.1|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-09-21|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-09-22|en}}. It will be on all wikis from {{#time:j xg|2021-09-23|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[s:Special:ApiHelp/query+proofreadinfo|meta=proofreadpage API]] has changed. The <bdi lang="zxx" dir="ltr"><code><nowiki>piprop</nowiki></code></bdi> parameter has been renamed to <bdi lang="zxx" dir="ltr"><code><nowiki>prpiprop</nowiki></code></bdi>. API users should update their code to avoid unrecognized parameter warnings. Pywikibot users should upgrade to 6.6.0. [https://phabricator.wikimedia.org/T290585] '''Future changes''' * The [[mw:Special:MyLanguage/Help:DiscussionTools#Replying|Reply tool]] will be deployed to the remaining wikis in the coming weeks. It is currently part of "{{int:discussiontools-preference-label}}" in [[Special:Preferences#mw-prefsection-betafeatures|Beta features]] at most wikis. You will be able to turn it off in [[Special:Preferences#mw-prefsection-editing-discussion|Editing Preferences]]. [https://phabricator.wikimedia.org/T262331] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[mw:MediaWiki_1.37/Deprecation_of_legacy_API_token_parameters|previously announced]] change to how you obtain tokens from the API has been delayed to September 21 because of an incompatibility with Pywikibot. Bot operators using Pywikibot can follow [[phab:T291202|T291202]] for progress on a fix, and should plan to upgrade to 6.6.1 when it is released. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 18:32, 20 September 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22043415 --> == [[m:Special:MyLanguage/Tech/News/2021/39|Tech News: 2021-39]] == <section begin="technews-2021-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/39|Translations]] are available. '''Recent changes''' * [[w:en:IOS|iOS 15]] has a new function called [https://support.apple.com/en-us/HT212614 Private Relay] (Apple website). This can hide the user's IP when they use [[w:en:Safari (software)|Safari]] browser. This is like using a [[w:en:Virtual private network|VPN]] in that we see another IP address instead. It is opt-in and only for those who pay extra for [[w:en:ICloud|iCloud]]. It will come to Safari users on [[:w:en:OSX|OSX]] later. There is a [[phab:T289795|technical discussion]] about what this means for the Wikimedia wikis. '''Problems''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Some gadgets and user-scripts add items to the [[m:Customization:Explaining_skins#Portlets|portlets]] (article tools) part of the skin. A recent change to the HTML may have made those links a different font-size. This can be fixed by adding the CSS class <bdi lang="zxx" dir="ltr"><code>.vector-menu-dropdown-noicon</code></bdi>. [https://phabricator.wikimedia.org/T291438] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.2|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-09-28|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-09-29|en}}. It will be on all wikis from {{#time:j xg|2021-09-30|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * The [[mw:Special:MyLanguage/Onboarding_new_Wikipedians#New_experience|GettingStarted extension]] was built in 2013, and provides an onboarding process for new account holders in a few versions of Wikipedia. However, the recently developed [[mw:Special:MyLanguage/Growth/Feature_summary|Growth features]] provide a better onboarding experience. Since the vast majority of Wikipedias now have access to the Growth features, GettingStarted will be deactivated starting on 4 October. [https://phabricator.wikimedia.org/T235752] * A small number of users will not be able to connect to the Wikimedia wikis after 30 September. This is because an old [[:w:en:root certificate|root certificate]] will no longer work. They will also have problems with many other websites. Users who have updated their software in the last five years are unlikely to have problems. Users in Europe, Africa and Asia are less likely to have immediate problems even if their software is too old. You can [[m:Special:MyLanguage/HTTPS/2021 Let's Encrypt root expiry|read more]]. * You can [[mw:Special:MyLanguage/Help:Notifications|receive notifications]] when someone leaves a comment on user talk page or mentions you in a talk page comment. Clicking the notification link will now bring you to the comment and highlight it. Previously, doing so brought you to the top of the section that contained the comment. You can find [[phab:T282029|more information in T282029.]] '''Future changes''' * The [[mw:Special:MyLanguage/Help:DiscussionTools#Replying|Reply tool]] will be deployed to the remaining wikis in the coming weeks. It is currently part of "{{int:discussiontools-preference-label}}" in [[Special:Preferences#mw-prefsection-betafeatures|Beta features]] at most wikis. You will be able to turn it off in [[Special:Preferences#mw-prefsection-editing-discussion|Editing Preferences]]. [[phab:T288485|See the list of wikis.]] [https://phabricator.wikimedia.org/T262331] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W39"/> 22:23, 27 September 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22077885 --> == [[m:Special:MyLanguage/Tech/News/2021/40|Tech News: 2021-40]] == <section begin="tech-newsletter-content"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/40|Translations]] are available. '''Recent changes''' * A more efficient way of sending changes from Wikidata to Wikimedia wikis that show them has been enabled for the following 10 wikis: mediawiki.org, the Italian, Catalan, Hebrew and Vietnamese Wikipedias, French Wikisource, and English Wikivoygage, Wikibooks, Wiktionary and Wikinews. If you notice anything strange about how changes from Wikidata appear in recent changes or your watchlist on those wikis you can [[phab:T48643|let the developers know]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.3|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-10-05|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-10-06|en}}. It will be on all wikis from {{#time:j xg|2021-10-07|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Some gadgets and bots that use the API to read the AbuseFilter log might break. The <bdi lang="zxx" dir="ltr"><code>hidden</code></bdi> property will no longer say an entry is <bdi lang="zxx" dir="ltr"><code>implicit</code></bdi> for unsuppressed log entries about suppressed edits. If your bot needs to know this, do a separate revision query. Additionally, the property will have the value <bdi lang="zxx" dir="ltr"><code>false</code></bdi> for visible entries; previously, it wasn't included in the response. [https://phabricator.wikimedia.org/T291718] * A more efficient way of sending changes from Wikidata to Wikimedia wikis that show them will be enabled for ''all production wikis''. If you notice anything strange about how changes from Wikidata appear in recent changes or your watchlist you can [[phab:T48643|let the developers know]]. '''Future changes''' * You can soon get cross-wiki notifications in the [[mw:Wikimedia Apps/Team/iOS|iOS Wikipedia app]]. You can also get notifications as push notifications. More notification updates will follow in later versions. [https://www.mediawiki.org/wiki/Wikimedia_Apps/Team/iOS/Notifications#September_2021_update] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The JavaScript variables <bdi lang="zxx" dir="ltr"><code>wgExtraSignatureNamespaces</code></bdi>, <bdi lang="zxx" dir="ltr"><code>wgLegalTitleChars</code></bdi>, and <bdi lang="zxx" dir="ltr"><code>wgIllegalFileChars</code></bdi> will soon be removed from <bdi lang="zxx" dir="ltr"><code>[[mw:Special:MyLanguage/Manual:Interface/JavaScript#mw.config|mw.config]]</code></bdi>. These are not part of the "stable" variables available for use in wiki JavaScript. [https://phabricator.wikimedia.org/T292011] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The JavaScript variables <bdi lang="zxx" dir="ltr"><code>wgCookiePrefix</code></bdi>, <bdi lang="zxx" dir="ltr"><code>wgCookieDomain</code></bdi>, <bdi lang="zxx" dir="ltr"><code>wgCookiePath</code></bdi>, and <bdi lang="zxx" dir="ltr"><code>wgCookieExpiration</code></bdi> will soon be removed from mw.config. Scripts should instead use <bdi lang="zxx" dir="ltr"><code>mw.cookie</code></bdi> from the "<bdi lang="zxx" dir="ltr">[[mw:ResourceLoader/Core_modules#mediawiki.cookie|mediawiki.cookie]]</bdi>" module. [https://phabricator.wikimedia.org/T291760] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="tech-newsletter-content"/> 16:32, 4 October 2021 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22101208 --> == [[m:Special:MyLanguage/Tech/News/2021/41|Tech News: 2021-41]] == <section begin="technews-2021-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/41|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.4|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-10-12|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-10-13|en}}. It will be on all wikis from {{#time:j xg|2021-10-14|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * The [[mw:Manual:Table_of_contents#Auto-numbering|"auto-number headings" preference]] is being removed. You can read [[phab:T284921]] for the reasons and discussion. This change was [[m:Tech/News/2021/26|previously]] announced. [[mw:Snippets/Auto-number_headings|A JavaScript snippet]] is available which can be used to create a Gadget on wikis that still want to support auto-numbering. '''Meetings''' * You can join a meeting about the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Desktop Improvements]]. A demonstration version of the [[mw:Reading/Web/Desktop Improvements/Features/Sticky Header|newest feature]] will be shown. The event will take place on Tuesday, 12 October at 16:00 UTC. [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/Talk to Web/12-10-2021|See how to join]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W41"/> 15:30, 11 October 2021 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22152137 --> == [[m:Special:MyLanguage/Tech/News/2021/42|Tech News: 2021-42]] == <section begin="technews-2021-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/42|Translations]] are available. '''Recent changes''' *[[m:Toolhub|Toolhub]] is a catalogue to make it easier to find software tools that can be used for working on the Wikimedia projects. You can [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/LF4SSR4QRCKV6NPRFGUAQWUFQISVIPTS/ read more]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-10-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-10-20|en}}. It will be on all wikis from {{#time:j xg|2021-10-21|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Future changes''' * The developers of the [[mw:Wikimedia Apps/Team/Android|Wikipedia Android app]] are working on [[mw:Wikimedia Apps/Team/Android/Communication|communication in the app]]. You can now answer questions in [[mw:Wikimedia Apps/Team/Android/Communication/UsertestingOctober2021|survey]] to help the development. * 3–5% of editors may be blocked in the next few months. This is because of a new service in Safari, which is similar to a [[w:en:Proxy server|proxy]] or a [[w:en:VPN|VPN]]. It is called iCloud Private Relay. There is a [[m:Special:MyLanguage/Apple iCloud Private Relay|discussion about this]] on Meta. The goal is to learn what iCloud Private Relay could mean for the communities. * [[m:Special:MyLanguage/Wikimedia Enterprise|Wikimedia Enterprise]] is a new [[w:en:API|API]] for those who use a lot of information from the Wikimedia projects on other sites. It is a way to get big commercial users to pay for the data. There will soon be a copy of the Wikimedia Enterprise dataset. You can [https://lists.wikimedia.org/hyperkitty/list/wikitech-ambassadors@lists.wikimedia.org/message/B2AX6PWH5MBKB4L63NFZY3ADBQG7MSBA/ read more]. You can also ask the team questions [https://wikimedia.zoom.us/j/88994018553 on Zoom] on [https://www.timeanddate.com/worldclock/fixedtime.html?hour=15&min=00&sec=0&day=22&month=10&year=2021 22 October 15:00 UTC]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W42"/> 20:53, 18 October 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22176877 --> == [[m:Special:MyLanguage/Tech/News/2021/43|Tech News: 2021-43]] == <section begin="technews-2021-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/43|Translations]] are available. '''Recent changes''' * The [[m:Special:MyLanguage/Coolest_Tool_Award|Coolest Tool Award 2021]] is looking for nominations. You can recommend tools until 27 October. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.6|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-10-26|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-10-27|en}}. It will be on all wikis from {{#time:j xg|2021-10-28|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Future changes''' *[[m:Special:MyLanguage/Help:Diff|Diff pages]] will have an improved copy and pasting experience. [[m:Special:MyLanguage/Community Wishlist Survey 2021/Copy paste diffs|The changes]] will allow the text in the diff for before and after to be treated as separate columns and will remove any unwanted syntax. [https://phabricator.wikimedia.org/T192526] * The version of the [[w:en:Liberation fonts|Liberation fonts]] used in SVG files will be upgraded. Only new thumbnails will be affected. Liberation Sans Narrow will not change. [https://phabricator.wikimedia.org/T253600] '''Meetings''' * You can join a meeting about the [[m:Special:MyLanguage/Community Wishlist Survey|Community Wishlist Survey]]. News about the [[m:Special:MyLanguage/Community Wishlist Survey 2021/Warn when linking to disambiguation pages|disambiguation]] and the [[m:Special:MyLanguage/Community Wishlist Survey 2021/Real Time Preview for Wikitext|real-time preview]] wishes will be shown. The event will take place on Wednesday, 27 October at 14:30 UTC. [[m:Special:MyLanguage/Community Wishlist Survey/Updates/Talk to Us|See how to join]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W43"/> 20:08, 25 October 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22232718 --> == [[m:Special:MyLanguage/Tech/News/2021/44|Tech News: 2021-44]] == <section begin="technews-2021-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/44|Translations]] are available. '''Recent changes''' * There is a limit on the amount of emails a user can send each day. This limit is now global instead of per-wiki. This change is to prevent abuse. [https://phabricator.wikimedia.org/T293866] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-11-02|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-11-03|en}}. It will be on all wikis from {{#time:j xg|2021-11-04|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W44"/> 20:28, 1 November 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22269406 --> == [[m:Special:MyLanguage/Tech/News/2021/45|Tech News: 2021-45]] == <section begin="technews-2021-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/45|Translations]] are available. '''Recent changes''' * Mobile IP editors are now able to receive warning notices indicating they have a talk page message on the mobile website (similar to the orange banners available on desktop). These notices will be displayed on every page outside of the main namespace and every time the user attempts to edit. The notice on desktop now has a slightly different colour. [https://phabricator.wikimedia.org/T284642][https://phabricator.wikimedia.org/T278105] '''Changes later this week''' * [[phab:T294321|Wikidata will be read-only]] for a few minutes on 11 November. This will happen around [https://zonestamp.toolforge.org/1636610400 06:00 UTC]. This is for database maintenance. [https://phabricator.wikimedia.org/T294321] * There is no new MediaWiki version this week. '''Future changes''' * In the future, unregistered editors will be given an identity that is not their [[:w:en:IP address|IP address]]. This is for legal reasons. A new user right will let editors who need to know the IPs of unregistered accounts to fight vandalism, spam, and harassment, see the IP. You can read the [[m:IP Editing: Privacy Enhancement and Abuse Mitigation#IP Masking Implementation Approaches (FAQ)|suggestions for how that identity could work]] and [[m:Talk:IP Editing: Privacy Enhancement and Abuse Mitigation|discuss on the talk page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W45"/> 20:36, 8 November 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22311003 --> == [[m:Special:MyLanguage/Tech/News/2021/46|Tech News: 2021-46]] == <section begin="technews-2021-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/46|Translations]] are available. '''Recent changes''' * Most [[c:Special:MyLanguage/Commons:Maximum_file_size#MAXTHUMB|large file uploads]] errors that had messages like "<bdi lang="zxx" dir="ltr"><code>stashfailed</code></bdi>" or "<bdi lang="zxx" dir="ltr"><code>DBQueryError</code></bdi>" have now been fixed. An [[wikitech:Incident documentation/2021-11-04 large file upload timeouts|incident report]] is available. '''Problems''' * Sometimes, edits made on iOS using the visual editor save groups of numbers as telephone number links, because of a feature in the operating system. This problem is under investigation. [https://phabricator.wikimedia.org/T116525] * There was a problem with search last week. Many search requests did not work for 2 hours because of a configuration error. [https://wikitech.wikimedia.org/wiki/Incident_documentation/2021-11-10_cirrussearch_commonsfile_outage] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.9|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-11-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-11-17|en}}. It will be on all wikis from {{#time:j xg|2021-11-18|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W46"/> 22:06, 15 November 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22338097 --> == [[m:Special:MyLanguage/Tech/News/2021/47|Tech News: 2021-47]] == <section begin="technews-2021-W47"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/47|Translations]] are available. '''Changes later this week''' * There is no new MediaWiki version this week. *The template dialog in VisualEditor and in the [[Special:Preferences#mw-prefsection-betafeatures|new wikitext mode]] Beta feature will be [[m:WMDE Technical Wishes/VisualEditor template dialog improvements|heavily improved]] on [[phab:T286992|a few wikis]]. Your [[m:Talk:WMDE Technical Wishes/VisualEditor template dialog improvements|feedback is welcome]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/47|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W47"/> 20:02, 22 November 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22366010 --> == [[m:Special:MyLanguage/Tech/News/2021/48|Tech News: 2021-48]] == <section begin="technews-2021-W48"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/48|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.11|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-11-30|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-12-01|en}}. It will be on all wikis from {{#time:j xg|2021-12-02|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/48|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W48"/> 21:15, 29 November 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22375666 --> == [[m:Special:MyLanguage/Tech/News/2021/49|Tech News: 2021-49]] == <section begin="technews-2021-W49"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/49|Translations]] are available. '''Problems''' * MediaWiki 1.38-wmf.11 was scheduled to be deployed on some wikis last week. The deployment was delayed because of unexpected problems. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.12|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-12-07|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-12-08|en}}. It will be on all wikis from {{#time:j xg|2021-12-09|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * At all Wikipedias, a Mentor Dashboard is now available at <bdi lang="zxx" dir="ltr"><code><nowiki>Special:MentorDashboard</nowiki></code></bdi>. It allows registered mentors, who take care of newcomers' first steps, to monitor their assigned newcomers' activity. It is part of the [[mw:Special:MyLanguage/Growth/Feature summary|Growth features]]. You can learn more about [[mw:Special:MyLanguage/Growth/Communities/How_to_configure_the_mentors%27_list|activating the mentor list]] on your wiki and about [[mw:Special:MyLanguage/Growth/Mentor dashboard|the mentor dashboard project]]. * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The predecessor to the current [[mw:API|MediaWiki Action API]] (which was created in 2008), <bdi lang="zxx" dir="ltr"><code><nowiki>action=ajax</nowiki></code></bdi>, will be removed this week. Any scripts or bots using it will need to switch to the corresponding API module. [https://phabricator.wikimedia.org/T42786] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] An old ResourceLoader module, <bdi lang="zxx" dir="ltr"><code><nowiki>jquery.jStorage</nowiki></code></bdi>, which was deprecated in 2016, will be removed this week. Any scripts or bots using it will need to switch to <bdi lang="zxx" dir="ltr"><code><nowiki>mediawiki.storage</nowiki></code></bdi> instead. [https://phabricator.wikimedia.org/T143034] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/49|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W49"/> 21:59, 6 December 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22413926 --> == [[m:Special:MyLanguage/Tech/News/2021/50|Tech News: 2021-50]] == <section begin="technews-2021-W50"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/50|Translations]] are available. '''Recent changes''' * There are now default [[m:Special:MyLanguage/Help:Namespace#Other_namespace_aliases|short aliases]] for the "Project:" namespace on most wikis. E.g. On Wikibooks wikis, <bdi lang="zxx" dir="ltr"><code><nowiki>[[WB:]]</nowiki></code></bdi> will go to the local language default for the <bdi lang="zxx" dir="ltr"><code><nowiki>[[Project:]]</nowiki></code></bdi> namespace. This change is intended to help the smaller communities have easy access to this feature. Additional local aliases can still be requested via [[m:Special:MyLanguage/Requesting wiki configuration changes|the usual process]]. [https://phabricator.wikimedia.org/T293839] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.13|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2021-12-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2021-12-15|en}}. It will be on all wikis from {{#time:j xg|2021-12-16|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/50|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W50"/> 22:27, 13 December 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22441074 --> == [[m:Special:MyLanguage/Tech/News/2021/51|Tech News: 2021-51]] == <section begin="technews-2021-W51"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2021/51|Translations]] are available. '''Tech News''' * Because of the [[w:en:Christmas and holiday season|holidays]] the next issue of Tech News will be sent out on 10 January 2022. '''Recent changes''' * Queries made by the DynamicPageList extension (<bdi lang="zxx" dir="ltr"><code><nowiki><DynamicPageList></nowiki></code></bdi>) are now only allowed to run for 10 seconds and error if they take longer. This is in response to multiple outages where long-running queries caused an outage on all wikis. [https://phabricator.wikimedia.org/T287380#7575719] '''Changes later this week''' * There is no new MediaWiki version this week or next week. '''Future changes''' * The developers of the Wikipedia iOS app are looking for testers who edit in multiple languages. You can [[mw:Wikimedia Apps/Team/iOS/202112 testing|read more and let them know if you are interested]]. * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The Wikimedia [[wikitech:Portal:Cloud VPS|Cloud VPS]] hosts technical projects for the Wikimedia movement. Developers need to [[wikitech:News/Cloud VPS 2021 Purge|claim projects]] they use. This is because old and unused projects are removed once a year. Unclaimed projects can be shut down from February. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/2B7KYL5VLQNHGQQHMYLW7KTUKXKAYY3T/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2021/51|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2021-W51"/> 22:05, 20 December 2021 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22465395 --> == [[m:Special:MyLanguage/Tech/News/2022/02|Tech News: 2022-02]] == <section begin="technews-2022-W02"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/02|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] A <bdi lang="zxx" dir="ltr"><code>oauth_consumer</code></bdi> variable has been added to the [[mw:Special:MyLanguage/AbuseFilter|AbuseFilter]] to enable identifying changes made by specific tools. [https://phabricator.wikimedia.org/T298281] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Gadgets are [[mw:Special:MyLanguage/ResourceLoader/Migration_guide_(users)#Package_Gadgets|now able to directly include JSON pages]]. This means some gadgets can now be configured by administrators without needing the interface administrator permission, such as with the Geonotice gadget. [https://phabricator.wikimedia.org/T198758] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Gadgets [[mw:Extension:Gadgets#Options|can now specify page actions]] on which they are available. For example, <bdi lang="zxx" dir="ltr"><code>|actions=edit,history</code></bdi> will load a gadget only while editing and on history pages. [https://phabricator.wikimedia.org/T63007] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] Gadgets can now be loaded on demand with the <bdi lang="zxx" dir="ltr"><code>withgadget</code></bdi> URL parameter. This can be used to replace [[mw:Special:MyLanguage/Snippets/Load JS and CSS by URL|an earlier snippet]] that typically looks like <bdi lang="zxx" dir="ltr"><code>withJS</code></bdi> or <bdi lang="zxx" dir="ltr"><code>withCSS</code></bdi>. [https://phabricator.wikimedia.org/T29766] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] At wikis where [[mw:Special:MyLanguage/Growth/Communities/How to configure the mentors' list|the Mentorship system is configured]], you can now use the Action API to get a list of a [[mw:Special:MyLanguage/Growth/Mentor_dashboard|mentor's]] mentees. [https://phabricator.wikimedia.org/T291966] * The heading on the main page can now be configured using <span class="mw-content-ltr" lang="en" dir="ltr">[[MediaWiki:Mainpage-title-loggedin]]</span> for logged-in users and <span class="mw-content-ltr" lang="en" dir="ltr">[[MediaWiki:Mainpage-title]]</span> for logged-out users. Any CSS that was previously used to hide the heading should be removed. [https://meta.wikimedia.org/wiki/Special:MyLanguage/Small_wiki_toolkits/Starter_kit/Main_page_customization#hide-heading] [https://phabricator.wikimedia.org/T298715] * Four special pages (and their API counterparts) now have a maximum database query execution time of 30 seconds. These special pages are: RecentChanges, Watchlist, Contributions, and Log. This change will help with site performance and stability. You can read [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/IPJNO75HYAQWIGTHI5LJHTDVLVOC4LJP/ more details about this change] including some possible solutions if this affects your workflows. [https://phabricator.wikimedia.org/T297708] * The [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Features/Sticky Header|sticky header]] has been deployed for 50% of logged-in users on [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Frequently asked questions#pilot-wikis|more than 10 wikis]]. This is part of the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Desktop Improvements]]. See [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Participate|how to take part in the project]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.17|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-01-11|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-01-12|en}}. It will be on all wikis from {{#time:j xg|2022-01-13|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Events''' * [[m:Special:MyLanguage/Community Wishlist Survey 2022|Community Wishlist Survey 2022]] begins. All contributors to the Wikimedia projects can propose for tools and platform improvements. The proposal phase takes place from {{#time:j xg|2022-01-10|en}} 18:00 UTC to {{#time:j xg|2022-01-23|en}} 18:00 UTC. [[m:Special:MyLanguage/Community_Wishlist_Survey/FAQ|Learn more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/02|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W02"/> 01:23, 11 January 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22562156 --> == [[m:Special:MyLanguage/Tech/News/2022/03|Tech News: 2022-03]] == <section begin="technews-2022-W03"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/03|Translations]] are available. '''Recent changes''' * When using [[mw:Special:MyLanguage/Extension:WikiEditor|WikiEditor]] (also known as the 2010 wikitext editor), people will now see a warning if they link to disambiguation pages. If you click "{{int:Disambiguator-review-link}}" in the warning, it will ask you to correct the link to a more specific term. You can [[m:Community Wishlist Survey 2021/Warn when linking to disambiguation pages#Jan 12, 2021: Turning on the changes for all Wikis|read more information]] about this completed 2021 Community Wishlist item. * You can [[mw:Special:MyLanguage/Help:DiscussionTools#subscribe|automatically subscribe to all of the talk page discussions]] that you start or comment in using [[mw:Special:MyLanguage/Talk pages project/Feature summary|DiscussionTools]]. You will receive [[mw:Special:MyLanguage/Notifications|notifications]] when another editor replies. This is available at most wikis. Go to your [[Special:Preferences#mw-prefsection-editing-discussion|Preferences]] and turn on "{{int:discussiontools-preference-autotopicsub}}". [https://phabricator.wikimedia.org/T263819] * When asked to create a new page or talk page section, input fields can be [[mw:Special:MyLanguage/Manual:Creating_pages_with_preloaded_text|"preloaded" with some text]]. This feature is now limited to wikitext pages. This is so users can't be tricked into making malicious edits. There is a discussion about [[phab:T297725|if this feature should be re-enabled]] for some content types. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.18|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-01-18|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-01-19|en}}. It will be on all wikis from {{#time:j xg|2022-01-20|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Events''' * [[m:Special:MyLanguage/Community Wishlist Survey 2022|Community Wishlist Survey 2022]] continues. All contributors to the Wikimedia projects can propose for tools and platform improvements. The proposal phase takes place from {{#time:j xg|2022-01-10|en}} 18:00 UTC to {{#time:j xg|2022-01-23|en}} 18:00 UTC. [[m:Special:MyLanguage/Community_Wishlist_Survey/FAQ|Learn more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/03|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W03"/> 19:55, 17 January 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22620285 --> == [[m:Special:MyLanguage/Tech/News/2022/04|Tech News: 2022-04]] == <section begin="technews-2022-W04"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/04|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.19|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-01-25|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-01-26|en}}. It will be on all wikis from {{#time:j xg|2022-01-27|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * The following languages can now be used with [[mw:Special:MyLanguage/Extension:SyntaxHighlight|syntax highlighting]]: BDD, Elpi, LilyPond, Maxima, Rita, Savi, Sed, Sophia, Spice, .SRCINFO. * You can now access your watchlist from outside of the user menu in the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|new Vector skin]]. The watchlist link appears next to the notification icons if you are at the top of the page. [https://phabricator.wikimedia.org/T289619] '''Events''' * You can see the results of the [[m:Special:MyLanguage/Coolest Tool Award|Coolest Tool Award 2021]] and learn more about 14 tools which were selected this year. * You can [[m:Special:MyLanguage/Community_Wishlist_Survey/Help_us|translate, promote]], or comment on [[m:Special:MyLanguage/Community Wishlist Survey 2022/Proposals|the proposals]] in the Community Wishlist Survey. Voting will begin on {{#time:j xg|2022-01-28|en}}. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/04|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W04"/> 21:38, 24 January 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22644148 --> == [[m:Special:MyLanguage/Tech/News/2022/05|Tech News: 2022-05]] == <section begin="technews-2022-W05"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/05|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] If a gadget should support the new <bdi lang="zxx" dir="ltr"><code>?withgadget</code></bdi> URL parameter that was [[m:Special:MyLanguage/Tech/News/2022/02|announced]] 3 weeks ago, then it must now also specify <bdi lang="zxx" dir="ltr"><code>supportsUrlLoad</code></bdi> in the gadget definition ([[mw:Special:MyLanguage/Extension:Gadgets#supportsUrlLoad|documentation]]). [https://phabricator.wikimedia.org/T29766] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.20|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-02-01|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-02-02|en}}. It will be on all wikis from {{#time:j xg|2022-02-03|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Future changes''' * A change that was [[m:Special:MyLanguage/Tech/News/2021/16|announced]] last year was delayed. It is now ready to move ahead: ** The user group <code>oversight</code> will be renamed <code>suppress</code>. This is for [[phab:T109327|technical reasons]]. This is the technical name. It doesn't affect what you call the editors with this user right on your wiki. This is planned to happen in three weeks. You can comment [[phab:T112147|in Phabricator]] if you have objections. As usual, these labels can be translated on translatewiki ([[phab:T112147|direct links are available]]) or by administrators on your wiki. '''Events''' * You can vote on proposals in the [[m:Special:MyLanguage/Community Wishlist Survey 2022|Community Wishlist Survey]] between 28 January and 11 February. The survey decides what the [[m:Special:MyLanguage/Community Tech|Community Tech team]] will work on. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/05|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W05"/> 17:42, 31 January 2022 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22721804 --> == [[m:Special:MyLanguage/Tech/News/2022/06|Tech News: 2022-06]] == <section begin="technews-2022-W06"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/06|Translations]] are available. '''Recent changes''' * English Wikipedia recently set up a gadget for dark mode. You can enable it there, or request help from an [[m:Special:MyLanguage/Interface administrators|interface administrator]] to set it up on your wiki ([[w:en:Wikipedia:Dark mode (gadget)|instructions and screenshot]]). * Category counts are sometimes wrong. They will now be completely recounted at the beginning of every month. [https://phabricator.wikimedia.org/T299823] '''Problems''' * A code-change last week to fix a bug with [[mw:Special:MyLanguage/Manual:Live preview|Live Preview]] may have caused problems with some local gadgets and user-scripts. Any code with skin-specific behaviour for <bdi lang="zxx" dir="ltr"><code>vector</code></bdi> should be updated to also check for <bdi lang="zxx" dir="ltr"><code>vector-2022</code></bdi>. [[phab:T300987|A code-snippet, global search, and example are available]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.21|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-02-08|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-02-09|en}}. It will be on all wikis from {{#time:j xg|2022-02-10|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/06|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W06"/> 21:15, 7 February 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22765948 --> == [[m:Special:MyLanguage/Tech/News/2022/07|Tech News: 2022-07]] == <section begin="technews-2022-W07"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/07|Translations]] are available. '''Recent changes''' * [[mw:Special:MyLanguage/Manual:Purge|Purging]] a category page with fewer than 5,000 members will now recount it completely. This will allow editors to fix incorrect counts when it is wrong. [https://phabricator.wikimedia.org/T85696] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.22|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-02-15|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-02-16|en}}. It will be on all wikis from {{#time:j xg|2022-02-17|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|Advanced item]] In the [[mw:Special:MyLanguage/Extension:AbuseFilter|AbuseFilter]] extension, the <code dir=ltr>rmspecials()</code> function has been updated so that it does not remove the "space" character. Wikis are advised to wrap all the uses of <code dir=ltr>rmspecials()</code> with <code dir=ltr>rmwhitespace()</code> wherever necessary to keep filters' behavior unchanged. You can use the search function on [[Special:AbuseFilter]] to locate its usage. [https://phabricator.wikimedia.org/T263024] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/07|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W07"/> 19:18, 14 February 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22821788 --> == [[m:Special:MyLanguage/Tech/News/2022/08|Tech News: 2022-08]] == <section begin="technews-2022-W08"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/08|Translations]] are available. '''Recent changes''' * [[Special:Nuke|Special:Nuke]] will now provide the standard deletion reasons (editable at <bdi lang="en" dir="ltr">[[MediaWiki:Deletereason-dropdown]]</bdi>) to use when mass-deleting pages. This was [[m:Community Wishlist Survey 2022/Admins and patrollers/Mass-delete to offer drop-down of standard reasons, or templated reasons.|a request in the 2022 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T25020] * At Wikipedias, all new accounts now get the [[mw:Special:MyLanguage/Growth/Feature_summary|Growth features]] by default when creating an account. Communities are encouraged to [[mw:Special:MyLanguage/Help:Growth/Tools/Account_creation|update their help resources]]. Previously, only 80% of new accounts would get the Growth features. A few Wikipedias remain unaffected by this change. [https://phabricator.wikimedia.org/T301820] * You can now prevent specific images that are used in a page from appearing in other locations, such as within PagePreviews or Search results. This is done with the markup <bdi lang="zxx" dir="ltr"><code><nowiki>class=notpageimage</nowiki></code></bdi>. For example, <code><nowiki>[[File:Example.png|class=notpageimage]]</nowiki></code>. [https://phabricator.wikimedia.org/T301588] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] There has been a change to the HTML of Special:Contributions, Special:MergeHistory, and History pages, to support the grouping of changes by date in [[mw:Special:MyLanguage/Skin:Minerva_Neue|the mobile skin]]. While unlikely, this may affect gadgets and user scripts. A [[phab:T298638|list of all the HTML changes]] is on Phabricator. '''Events''' * [[m:Special:MyLanguage/Community Wishlist Survey 2022/Results|Community Wishlist Survey results]] have been published. The [[m:Special:MyLanguage/Community Wishlist Survey/Updates/2022 results#leaderboard|ranking of prioritized proposals]] is also available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-02-22|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-02-23|en}}. It will be on all wikis from {{#time:j xg|2022-02-24|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Future changes''' * The software to play videos and audio files on pages will change soon on all wikis. The old player will be removed. Some audio players will become wider after this change. [[mw:Special:MyLanguage/Extension:TimedMediaHandler/VideoJS_Player|The new player]] has been a beta feature for over four years. [https://phabricator.wikimedia.org/T100106][https://phabricator.wikimedia.org/T248418] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Toolforge's underlying operating system is being updated. If you maintain any tools there, there are two options for migrating your tools into the new system. There are [[wikitech:News/Toolforge Stretch deprecation|details, deadlines, and instructions]] on Wikitech. [https://lists.wikimedia.org/hyperkitty/list/cloud-announce@lists.wikimedia.org/thread/EPJFISC52T7OOEFH5YYMZNL57O4VGSPR/] * Administrators will soon have [[m:Special:MyLanguage/Community Wishlist Survey 2021/(Un)delete associated talk page|the option to delete/undelete]] the associated "talk" page when they are deleting a given page. An API endpoint with this option will also be available. This was [[m:Community Wishlist Survey 2021/Admins and patrollers/(Un)delete associated talk page|a request from the 2021 Wishlist Survey]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/08|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W08"/> 19:12, 21 February 2022 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22847768 --> == [[m:Special:MyLanguage/Tech/News/2022/09|Tech News: 2022-09]] == <section begin="technews-2022-W09"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/09|Translations]] are available. '''Recent changes''' * When searching for edits by [[mw:Special:MyLanguage/Help:Tags|change tags]], e.g. in page history or user contributions, there is now a dropdown list of possible tags. This was [[m:Community Wishlist Survey 2022/Miscellaneous/Improve plain-text change tag selector|a request in the 2022 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T27909] * Mentors using the [[mw:Special:MyLanguage/Growth/Mentor_dashboard|Growth Mentor dashboard]] will now see newcomers assigned to them who have made at least one edit, up to 200 edits. Previously, all newcomers assigned to the mentor were visible on the dashboard, even ones without any edit or ones who made hundred of edits. Mentors can still change these values using the filters on their dashboard. Also, the last choice of filters will now be saved. [https://phabricator.wikimedia.org/T301268][https://phabricator.wikimedia.org/T294460] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The user group <code>oversight</code> was renamed <code>suppress</code>. This is for [[phab:T109327|technical reasons]]. You may need to update any local references to the old name, e.g. gadgets, links to Special:Listusers, or uses of [[mw:Special:MyLanguage/Help:Magic_words|NUMBERINGROUP]]. '''Problems''' * The recent change to the HTML of [[mw:Special:MyLanguage/Help:Tracking changes|tracking changes]] pages caused some problems for screenreaders. This is being fixed. [https://phabricator.wikimedia.org/T298638] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.24|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-03-01|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-03-02|en}}. It will be on all wikis from {{#time:j xg|2022-03-03|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''Future changes''' * Working with templates will become easier. [[m:WMDE_Technical_Wishes/Templates|Several improvements]] are planned for March 9 on most wikis and on March 16 on English Wikipedia. The improvements include: Bracket matching, syntax highlighting colors, finding and inserting templates, and related visual editor features. * If you are a template developer or an interface administrator, and you are intentionally overriding or using the default CSS styles of user feedback boxes (the classes: <code dir=ltr>successbox, messagebox, errorbox, warningbox</code>), please note that these classes and associated CSS will soon be removed from MediaWiki core. This is to prevent problems when the same class-names are also used on a wiki. Please let us know by commenting at [[phab:T300314]] if you think you might be affected. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/09|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W09"/> 22:59, 28 February 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22902593 --> == [[m:Special:MyLanguage/Tech/News/2022/10|Tech News: 2022-10]] == <section begin="technews-2022-W10"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/10|Translations]] are available. '''Problems''' * There was a problem with some interface labels last week. It will be fixed this week. This change was part of ongoing work to simplify the support for skins which do not have active maintainers. [https://phabricator.wikimedia.org/T301203] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.25|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-03-08|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-03-09|en}}. It will be on all wikis from {{#time:j xg|2022-03-10|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/10|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W10"/> 21:16, 7 March 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22958074 --> == [[m:Special:MyLanguage/Tech/News/2022/11|Tech News: 2022-11]] == <section begin="technews-2022-W11"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/11|Translations]] are available. '''Recent changes''' * In the Wikipedia Android app [[mw:Special:MyLanguage/Wikimedia_Apps/Team/Android/Communication#Updates|it is now possible]] to change the toolbar at the bottom so the tools you use more often are easier to click on. The app now also has a focused reading mode. [https://phabricator.wikimedia.org/T296753][https://phabricator.wikimedia.org/T254771] '''Problems''' * There was a problem with the collection of some page-view data from June 2021 to January 2022 on all wikis. This means the statistics are incomplete. To help calculate which projects and regions were most affected, relevant datasets are being retained for 30 extra days. You can [[m:Talk:Data_retention_guidelines#Added_exception_for_page_views_investigation|read more on Meta-wiki]]. * There was a problem with the databases on March 10. All wikis were unreachable for logged-in users for 12 minutes. Logged-out users could read pages but could not edit or access uncached content then. [https://wikitech.wikimedia.org/wiki/Incident_documentation/2022-03-10_MediaWiki_availability] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.38/wmf.26|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-03-15|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-03-16|en}}. It will be on all wikis from {{#time:j xg|2022-03-17|en}} ([[mw:MediaWiki 1.38/Roadmap|calendar]]). * When [[mw:Special:MyLanguage/Help:System_message#Finding_messages_and_documentation|using <bdi lang="zxx" dir="ltr"><code>uselang=qqx</code></bdi> to find localisation messages]], it will now show all possible message keys for navigation tabs such as "{{int:vector-view-history}}". [https://phabricator.wikimedia.org/T300069] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Access to [[{{#special:RevisionDelete}}]] has been expanded to include users who have <code dir=ltr>deletelogentry</code> and <code dir=ltr>deletedhistory</code> rights through their group memberships. Before, only those with the <code dir=ltr>deleterevision</code> right could access this special page. [https://phabricator.wikimedia.org/T301928] * On the [[{{#special:Undelete}}]] pages for diffs and revisions, there will be a link back to the main Undelete page with the list of revisions. [https://phabricator.wikimedia.org/T284114] '''Future changes''' * The Wikimedia Foundation has announced the IP Masking implementation strategy and next steps. The [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation#feb25|announcement can be read here]]. * The [[mw:Special:MyLanguage/Wikimedia Apps/Android FAQ|Wikipedia Android app]] developers are working on [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/Communication|new functions]] for user talk pages and article talk pages. [https://phabricator.wikimedia.org/T297617] '''Events''' * The [[mw:Wikimedia Hackathon 2022|Wikimedia Hackathon 2022]] will take place as a hybrid event on 20-22 May 2022. The Hackathon will be held online and there are grants available to support local in-person meetups around the world. Grants can be requested until 20 March. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/11|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W11"/> 22:07, 14 March 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=22993074 --> == [[m:Special:MyLanguage/Tech/News/2022/12|Tech News: 2022-12]] == <section begin="technews-2022-W12"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/12|Translations]] are available. '''New code release schedule for this week''' * There will be four MediaWiki releases this week, instead of just one. This is an experiment which should lead to fewer problems and to faster feature updates. The releases will be on all wikis, at different times, on Monday, Tuesday, and Wednesday. You can [[mw:Special:MyLanguage/Wikimedia Release Engineering Team/Trainsperiment week|read more about this project]]. '''Recent changes''' * You can now set how many search results to show by default in [[Special:Preferences#mw-prefsection-searchoptions|your Preferences]]. This was the 12th most popular wish in the [[m:Special:MyLanguage/Community Wishlist Survey 2022/Results|Community Wishlist Survey 2022]]. [https://phabricator.wikimedia.org/T215716] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The Jupyter notebooks tool [[wikitech:PAWS|PAWS]] has been updated to a new interface. [https://phabricator.wikimedia.org/T295043] '''Future changes''' * Interactive maps via [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] will soon work on wikis using the [[mw:Special:MyLanguage/Extension:FlaggedRevs|FlaggedRevisions]] extension. [https://wikimedia.sslsurvey.de/Kartographer-Workflows-EN/ Please tell us] which improvements you want to see in Kartographer. You can take this survey in simple English. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/12|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W12"/> 16:01, 21 March 2022 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23034693 --> == [[m:Special:MyLanguage/Tech/News/2022/13|Tech News: 2022-13]] == <section begin="technews-2022-W13"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/13|Translations]] are available. '''Recent changes''' * There is a simple new Wikimedia Commons upload tool available for macOS users, [[c:Commons:Sunflower|Sunflower]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-03-29|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-03-30|en}}. It will be on all wikis from {{#time:j xg|2022-03-31|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * Some wikis will be in read-only for a few minutes because of regular database maintenance. It will be performed on {{#time:j xg|2022-03-29|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s3.dblist targeted wikis]) and on {{#time:j xg|2022-03-31|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist targeted wikis]). [https://phabricator.wikimedia.org/T301850][https://phabricator.wikimedia.org/T303798] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/13|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W13"/> 19:54, 28 March 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23073711 --> == [[m:Special:MyLanguage/Tech/News/2022/14|Tech News: 2022-14]] == <section begin="technews-2022-W14"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/14|Translations]] are available. '''Problems''' * For a few days last week, edits that were suggested to newcomers were not tagged in the [[{{#special:recentchanges}}]] feed. This bug has been fixed. [https://phabricator.wikimedia.org/T304747] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.6|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-04-05|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-04-06|en}}. It will be on all wikis from {{#time:j xg|2022-04-07|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-04-07|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s4.dblist targeted wikis]). '''Future changes''' * Starting next week, Tech News' title will be translatable. When the newsletter is distributed, its title may not be <code dir=ltr>Tech News: 2022-14</code> anymore. It may affect some filters that have been set up by some communities. [https://phabricator.wikimedia.org/T302920] * Over the next few months, the "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" Growth feature [[phab:T304110|will become available to more Wikipedias]]. Each week, a few wikis will get the feature. You can test this tool at [[mw:Special:MyLanguage/Growth#deploymentstable|a few wikis where "Link recommendation" is already available]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/14|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W14"/> 21:01, 4 April 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23097604 --> == Tech News: 2022-15 == <section begin="technews-2022-W15"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/15|Translations]] are available. '''Recent changes''' * There is a new public status page at <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wikimediastatus.net/ www.wikimediastatus.net]</span>. This site shows five automated high-level metrics where you can see the overall health and performance of our wikis' technical environment. It also contains manually-written updates for widespread incidents, which are written as quickly as the engineers are able to do so while also fixing the actual problem. The site is separated from our production infrastructure and hosted by an external service, so that it can be accessed even if the wikis are briefly unavailable. You can [https://diff.wikimedia.org/2022/03/31/announcing-www-wikimediastatus-net/ read more about this project]. * On Wiktionary wikis, the software to play videos and audio files on pages has now changed. The old player has been removed. Some audio players will become wider after this change. [[mw:Special:MyLanguage/Extension:TimedMediaHandler/VideoJS_Player|The new player]] has been a beta feature for over four years. [https://phabricator.wikimedia.org/T100106][https://phabricator.wikimedia.org/T248418] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-04-12|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-04-13|en}}. It will be on all wikis from {{#time:j xg|2022-04-14|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/15|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W15"/> 19:44, 11 April 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23124108 --> == Tech News: 2022-16 == <section begin="technews-2022-W16"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/16|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.8|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-04-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-04-20|en}}. It will be on all wikis from {{#time:j xg|2022-04-21|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-04-19|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s7.dblist targeted wikis]) and on {{#time:j xg|2022-04-21|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s8.dblist targeted wikis]). * Administrators will now have [[m:Community Wishlist Survey 2021/(Un)delete associated talk page|the option to delete/undelete the associated "Talk" page]] when they are deleting a given page. An API endpoint with this option is also available. This concludes the [[m:Community Wishlist Survey 2021/Admins and patrollers/(Un)delete associated talk page|11th wish of the 2021 Community Wishlist Survey]]. * On [[mw:Special:MyLanguage/Reading/Web/Desktop_Improvements#test-wikis|selected wikis]], 50% of logged-in users will see the new [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Features/Table of contents|table of contents]]. When scrolling up and down the page, the table of contents will stay in the same place on the screen. This is part of the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Desktop Improvements]] project. [https://phabricator.wikimedia.org/T304169] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Message boxes produced by MediaWiki code will no longer have these CSS classes: <code dir=ltr>successbox</code>, <code dir=ltr>errorbox</code>, <code dir=ltr>warningbox</code>. The styles for those classes and <code dir=ltr>messagebox</code> will be removed from MediaWiki core. This only affects wikis that use these classes in wikitext, or change their appearance within site-wide CSS. Please review any local usage and definitions for these classes you may have. This was previously announced in the [[m:Special:MyLanguage/Tech/News/2022/09|28 February issue of Tech News]]. '''Future changes''' * [[mw:Special:MyLanguage/Extension:Kartographer|Kartographer]] will become compatible with [[mw:Special:MyLanguage/Extension:FlaggedRevs|FlaggedRevisions page stabilization]]. Kartographer maps will also work on pages with [[mw:Special:MyLanguage/Help:Pending changes|pending changes]]. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation#Project_descriptions] The Kartographer documentation has been thoroughly updated. [https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Extension:Kartographer/Getting_started] [https://www.mediawiki.org/wiki/Special:MyLanguage/Help:VisualEditor/Maps] [https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Extension:Kartographer] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/16|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W16"/> 23:11, 18 April 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23167004 --> == Tech News: 2022-17 == <section begin="technews-2022-W17"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/17|Translations]] are available. '''Recent changes''' * On [https://noc.wikimedia.org/conf/dblists/group1.dblist many wikis] (group 1), the software to play videos and audio files on pages has now changed. The old player has been removed. Some audio players will become wider after this change. [[mw:Special:MyLanguage/Extension:TimedMediaHandler/VideoJS_Player|The new player]] has been a beta feature for over four years. [https://phabricator.wikimedia.org/T100106][https://phabricator.wikimedia.org/T248418] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.9|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-04-26|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-04-27|en}}. It will be on all wikis from {{#time:j xg|2022-04-28|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-04-26|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s2.dblist targeted wikis]). * Some very old browsers and operating systems are no longer supported. Some things on the wikis might look weird or not work in very old browsers like Internet Explorer 9 or 10, Android 4, or Firefox 38 or older. [https://phabricator.wikimedia.org/T306486] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/17|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W17"/> 22:56, 25 April 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23187115 --> == Tech News: 2022-18 == <section begin="technews-2022-W18"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/18|Translations]] are available. '''Recent changes''' * On [https://noc.wikimedia.org/conf/dblists/group2.dblist all remaining wikis] (group 2), the software to play videos and audio files on pages has now changed. The old player has been removed. Some audio players will become wider after this change. [[mw:Special:MyLanguage/Extension:TimedMediaHandler/VideoJS_Player|The new player]] has been a beta feature for over four years. [https://phabricator.wikimedia.org/T100106][https://phabricator.wikimedia.org/T248418] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.10|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-05-03|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-05-04|en}}. It will be on all wikis from {{#time:j xg|2022-05-05|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). '''Future changes''' * The developers are working on talk pages in the [[mw:Wikimedia Apps/Team/iOS|Wikipedia app for iOS]]. You can [https://wikimedia.qualtrics.com/jfe/form/SV_9GBcHczQGLbQWTY give feedback]. You can take the survey in English, German, Hebrew or Chinese. * [[m:WMDE_Technical_Wishes/VisualEditor_template_dialog_improvements#Status_and_next_steps|Most wikis]] will receive an [[m:WMDE_Technical_Wishes/VisualEditor_template_dialog_improvements|improved template dialog]] in VisualEditor and New Wikitext mode. [https://phabricator.wikimedia.org/T296759] [https://phabricator.wikimedia.org/T306967] * If you use syntax highlighting while editing wikitext, you can soon activate a [[m:WMDE_Technical_Wishes/Improved_Color_Scheme_of_Syntax_Highlighting#Color-blind_mode|colorblind-friendly color scheme]]. [https://phabricator.wikimedia.org/T306867] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Several CSS IDs related to MediaWiki interface messages will be removed. Technical editors should please [[phab:T304363|review the list of IDs and links to their existing uses]]. These include <code dir=ltr>#mw-anon-edit-warning</code>, <code dir=ltr>#mw-undelete-revision</code> and 3 others. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/18|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W18"/> 19:33, 2 May 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23232924 --> == Tech News: 2022-19 == <section begin="technews-2022-W19"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/19|Translations]] are available. '''Recent changes''' * You can now see categories in the [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android|Wikipedia app for Android]]. [https://phabricator.wikimedia.org/T73966] '''Problems''' * Last week, there was a problem with Wikidata's search autocomplete. This has now been fixed. [https://phabricator.wikimedia.org/T307586] * Last week, all wikis had slow access or no access for 20 minutes, for logged-in users and non-cached pages. This was caused by a problem with a database change. [https://phabricator.wikimedia.org/T307647] '''Changes later this week''' * There is no new MediaWiki version this week. [https://phabricator.wikimedia.org/T305217#7894966] * [[m:WMDE Technical Wishes/Geoinformation#Current issues|Incompatibility issues]] with [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] and the [[mw:Special:MyLanguage/Help:Extension:FlaggedRevs|FlaggedRevs extension]] will be fixed: Deployment is planned for May 10 on all wikis. Kartographer will then be enabled on the [[phab:T307348|five wikis which have not yet enabled the extension]] on May 24. * The [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Vector (2022)]] skin will be set as the default on several more wikis, including Arabic and Catalan Wikipedias. Logged-in users will be able to switch back to the old Vector (2010). See the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/2022-04 for the largest wikis|latest update]] about Vector (2022). '''Future meetings''' * The next [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/Talk to Web|open meeting with the Web team]] about Vector (2022) will take place on 17 May. The following meetings are currently planned for: 7 June, 21 June, 5 July, 19 July. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/19|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W19"/> 15:22, 9 May 2022 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23256717 --> == Tech News: 2022-20 == <section begin="technews-2022-W20"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/20|Translations]] are available. '''Changes later this week''' * Some wikis can soon use the [[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|add a link]] feature. This will start on Wednesday. The wikis are {{int:project-localized-name-cawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ptwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-simplewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-svwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ukwiki/en}}. This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T304542] * The [[mw:Special:MyLanguage/Wikimedia Hackathon 2022|Wikimedia Hackathon 2022]] will take place online on May 20–22. It will be in English. There are also local [[mw:Special:MyLanguage/Wikimedia Hackathon 2022/Meetups|hackathon meetups]] in Germany, Ghana, Greece, India, Nigeria and the United States. Technically interested Wikimedians can work on software projects and learn new skills. You can also host a session or post a project you want to work on. * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.12|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-05-17|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-05-18|en}}. It will be on all wikis from {{#time:j xg|2022-05-19|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). '''Future changes''' * You can soon edit translatable pages in the visual editor. Translatable pages exist on for examples Meta and Commons. [https://diff.wikimedia.org/2022/05/12/mediawiki-1-38-brings-support-for-editing-translatable-pages-with-the-visual-editor/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/20|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W20"/> 18:58, 16 May 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23291515 --> == Tech News: 2022-21 == <section begin="technews-2022-W21"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/21|Translations]] are available. '''Recent changes''' * Administrators using the mobile web interface can now access Special:Block directly from user pages. [https://phabricator.wikimedia.org/T307341] * The <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wiktionary.org/ www.wiktionary.org]</span> portal page now uses an automated update system. Other [[m:Project_portals|project portals]] will be updated over the next few months. [https://phabricator.wikimedia.org/T304629] '''Problems''' * The Growth team maintains a mentorship program for newcomers. Previously, newcomers weren't able to opt out from the program. Starting May 19, 2022, newcomers are able to fully opt out from Growth mentorship, in case they do not wish to have any mentor at all. [https://phabricator.wikimedia.org/T287915] * Some editors cannot access the content translation tool if they load it by clicking from the contributions menu. This problem is being worked on. It should still work properly if accessed directly via Special:ContentTranslation. [https://phabricator.wikimedia.org/T308802] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.13|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-05-24|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-05-25|en}}. It will be on all wikis from {{#time:j xg|2022-05-26|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Gadget and user scripts developers are invited to give feedback on a [[mw:User:Jdlrobson/Extension:Gadget/Policy|proposed technical policy]] aiming to improve support from MediaWiki developers. [https://phabricator.wikimedia.org/T308686] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/21|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W21"/> 00:21, 24 May 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23317250 --> == Tech News: 2022-22 == <section begin="technews-2022-W22"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/22|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|Advanced item]] In the [[mw:Special:MyLanguage/Extension:AbuseFilter|AbuseFilter]] extension, an <code dir=ltr>ip_in_ranges()</code> function has been introduced to check if an IP is in any of the ranges. Wikis are advised to combine multiple <code dir=ltr>ip_in_range()</code> expressions joined by <code>|</code> into a single expression for better performance. You can use the search function on [[Special:AbuseFilter|Special:AbuseFilter]] to locate its usage. [https://phabricator.wikimedia.org/T305017] * The [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/IP Info feature|IP Info feature]] which helps abuse fighters access information about IPs, [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/IP Info feature#May 24, 2022|has been deployed]] to all wikis as a beta feature. This comes after weeks of beta testing on test.wikipedia.org. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.14|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-05-31|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-06-01|en}}. It will be on all wikis from {{#time:j xg|2022-06-02|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-05-31|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist targeted wikis]). * The [[mw:Special:MyLanguage/Help:DiscussionTools#New topic tool|New Topic Tool]] will be deployed for all editors at most wikis soon. You will be able to opt out from within the tool and in [[Special:Preferences#mw-prefsection-editing-discussion|Preferences]]. [https://www.mediawiki.org/wiki/Special:MyLanguage/Talk_pages_project/New_discussion][https://phabricator.wikimedia.org/T287804] * [[File:Octicons-tools.svg|15px|link=|Advanced item]] The [[:mw:Special:ApiHelp/query+usercontribs|list=usercontribs API]] will support fetching contributions from an [[mw:Special:MyLanguage/Help:Range blocks#Non-technical explanation|IP range]] soon. API users can set the <code>uciprange</code> parameter to get contributions from any IP range within [[:mw:Manual:$wgRangeContributionsCIDRLimit|the limit]]. [https://phabricator.wikimedia.org/T177150] * A new parser function will be introduced: <bdi lang="zxx" dir="ltr"><code><nowiki>{{=}}</nowiki></code></bdi>. It will replace existing templates named "=". It will insert an [[w:en:Equals sign|equal sign]]. This can be used to escape the equal sign in the parameter values of templates. [https://phabricator.wikimedia.org/T91154] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/22|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W22"/> 20:28, 30 May 2022 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23340178 --> == Tech News: 2022-23 == <section begin="technews-2022-W23"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/23|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.15|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-06-07|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-06-08|en}}. It will be on all wikis from {{#time:j xg|2022-06-09|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] A new <bdi lang="zxx" dir="ltr"><code>str_replace_regexp()</code></bdi> function can be used in [[Special:AbuseFilter|abuse filters]] to replace parts of text using a [[w:en:Regular expression|regular expression]]. [https://phabricator.wikimedia.org/T285468] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/23|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W23"/> 02:46, 7 June 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23366979 --> == Tech News: 2022-24 == <section begin="technews-2022-W24"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/24|Translations]] are available. '''Recent changes''' * All wikis can now use [[mw:Special:MyLanguage/Extension:Kartographer|Kartographer]] maps. Kartographer maps now also work on pages with [[mw:Special:MyLanguage/Help:Pending changes|pending changes]]. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation#Project_descriptions][https://phabricator.wikimedia.org/T307348] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.16|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-06-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-06-15|en}}. It will be on all wikis from {{#time:j xg|2022-06-16|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-06-14|en}} at 06:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s6.dblist targeted wikis]). [https://phabricator.wikimedia.org/T300471] * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-abwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-acewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-adywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-afwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-akwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-alswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-amwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-anwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-angwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-arcwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-arzwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-astwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-atjwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-avwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-aywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-azwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-azbwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T304548] * The [[mw:Special:MyLanguage/Help:DiscussionTools#New topic tool|New Topic Tool]] will be deployed for all editors at Commons, Wikidata, and some other wikis soon. You will be able to opt out from within the tool and in [[Special:Preferences#mw-prefsection-editing-discussion|Preferences]]. [https://www.mediawiki.org/wiki/Special:MyLanguage/Talk_pages_project/New_discussion][https://phabricator.wikimedia.org/T287804] '''Future meetings''' * The next [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/Talk to Web|open meeting with the Web team]] about Vector (2022) will take place today (13 June). The following meetings will take place on: 28 June, 12 July, 26 July. '''Future changes''' * By the end of July, the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Vector 2022]] skin should be ready to become the default across all wikis. Discussions on how to adjust it to the communities' needs will begin in the next weeks. It will always be possible to revert to the previous version on an individual basis. [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/2022-04 for the largest wikis|Learn more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/24|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W24"/> 16:58, 13 June 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23389956 --> == Tech News: 2022-25 == <section begin="technews-2022-W25"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/25|Translations]] are available. '''Recent changes''' * The [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android|Wikipedia App for Android]] now has an option for editing the whole page at once, located in the overflow menu (three-dots menu [[File:Ic more vert 36px.svg|15px|link=|alt=]]). [https://phabricator.wikimedia.org/T103622] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Some recent database changes may affect queries using the [[m:Research:Quarry|Quarry tool]]. Queries for <bdi lang="zxx" dir="ltr"><code>site_stats</code></bdi> at English Wikipedia, Commons, and Wikidata will need to be updated. [[phab:T306589|Read more]]. * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] A new <bdi lang="zxx" dir="ltr"><code>user_global_editcount</code></bdi> variable can be used in [[Special:AbuseFilter|abuse filters]] to avoid affecting globally active users. [https://phabricator.wikimedia.org/T130439] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.17|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-06-21|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-06-22|en}}. It will be on all wikis from {{#time:j xg|2022-06-23|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * Users of non-responsive skins (e.g. MonoBook or Vector) on mobile devices may notice a slight change in the default zoom level. This is intended to optimize zooming and ensure all interface elements are present on the page (for example the table of contents on Vector 2022). In the unlikely event this causes any problems with how you use the site, we'd love to understand better, please ping <span class="mw-content-ltr" lang="en" dir="ltr">[[m:User:Jon (WMF)|Jon (WMF)]]</span> to any on-wiki conversations. [https://phabricator.wikimedia.org/T306910] '''Future changes''' * The Beta Feature for [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] will be updated throughout July. Discussions will look different. You can see [[mw:Special:MyLanguage/Talk pages project/Usability/Prototype|some of the proposed changes]]. * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Parsoid's HTML output will soon stop annotating file links with different <bdi lang="zxx" dir="ltr"><code>typeof</code></bdi> attribute values, and instead use <bdi lang="zxx" dir="ltr"><code>mw:File</code></bdi> for all types. Tool authors should adjust any code that expects: <bdi lang="zxx" dir="ltr"><code>mw:Image</code></bdi>, <bdi lang="zxx" dir="ltr"><code>mw:Audio</code></bdi>, or <bdi lang="zxx" dir="ltr"><code>mw:Video</code></bdi>. [https://phabricator.wikimedia.org/T273505] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/25|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W25"/> 20:18, 20 June 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23425855 --> == Tech News: 2022-26 == <section begin="technews-2022-W26"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/26|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] [[m:Special:MyLanguage/Wikimedia Enterprise|Wikimedia Enterprise]] API service now has self-service accounts with free on-demand requests and monthly snapshots ([https://enterprise.wikimedia.com/docs/ API documentation]). Community access [[m:Special:MyLanguage/Wikimedia Enterprise/FAQ#community-access|via database dumps & Wikimedia Cloud Services]] continues. * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] [[d:Special:MyLanguage/Wikidata:Wiktionary#lua|All Wikimedia wikis can now use Wikidata Lexemes in Lua]] after creating local modules and templates. Discussions are welcome [[d:Wikidata_talk:Lexicographical_data#You_can_now_reuse_Wikidata_Lexemes_on_all_wikis|on the project talk page]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.18|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-06-28|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-06-29|en}}. It will be on all wikis from {{#time:j xg|2022-06-30|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-06-28|en}} at 06:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s7.dblist targeted wikis]). [https://phabricator.wikimedia.org/T311033] * Some global and cross-wiki services will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-06-30|en}} at 06:00 UTC. This will impact ContentTranslation, Echo, StructuredDiscussions, Growth experiments and a few more services. [https://phabricator.wikimedia.org/T300472] * Users will be able to sort columns within sortable tables in the mobile skin. [https://phabricator.wikimedia.org/T233340] '''Future meetings''' * The next [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/Talk to Web|open meeting with the Web team]] about Vector (2022) will take place tomorrow (28 June). The following meetings will take place on 12 July and 26 July. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/26|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W26"/> 20:02, 27 June 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23453785 --> == Tech News: 2022-27 == <section begin="technews-2022-W27"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/27|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.19|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-07-05|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-07-06|en}}. It will be on all wikis from {{#time:j xg|2022-07-07|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-07-05|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s6.dblist targeted wikis]) and on {{#time:j xg|2022-07-07|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s4.dblist targeted wikis]). * The Beta Feature for [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] will be updated throughout July. Discussions will look different. You can see [[mw:Special:MyLanguage/Talk pages project/Usability/Prototype|some of the proposed changes]]. * [[File:Octicons-tools.svg|15px|link=|alt=| Advanced item]] This change only affects pages in the main namespace in Wikisource. The Javascript config variable <bdi lang="zxx" dir="ltr"><code>proofreadpage_source_href</code></bdi> will be removed from <bdi lang="zxx" dir="ltr"><code>[[mw:Special:MyLanguage/Manual:Interface/JavaScript#mw.config|mw.config]]</code></bdi> and be replaced with the variable <bdi lang="zxx" dir="ltr"><code>prpSourceIndexPage</code></bdi>. [https://phabricator.wikimedia.org/T309490] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/27|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W27"/> 19:32, 4 July 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23466250 --> == Tech News: 2022-28 == <section begin="technews-2022-W28"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/28|Translations]] are available. '''Recent changes''' * In the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Vector 2022 skin]], the page title is now displayed above the tabs such as Discussion, Read, Edit, View history, or More. [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates#Page title/tabs switch|Learn more]]. [https://phabricator.wikimedia.org/T303549] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] It is now possible to easily view most of the configuration settings that apply to just one wiki, and to compare settings between two wikis if those settings are different. For example: [https://noc.wikimedia.org/wiki.php?wiki=jawiktionary Japanese Wiktionary settings], or [https://noc.wikimedia.org/wiki.php?wiki=eswiki&compare=eowiki settings that are different between the Spanish and Esperanto Wikipedias]. Local communities may want to [[m:Special:MyLanguage/Requesting_wiki_configuration_changes|discuss and propose changes]] to their local settings. Details about each of the named settings can be found by [[mw:Special:Search|searching MediaWiki.org]]. [https://phabricator.wikimedia.org/T308932] *The Anti-Harassment Tools team [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/IP Info feature#May|recently deployed]] the IP Info Feature as a [[Special:Preferences#mw-prefsection-betafeatures|Beta Feature at all wikis]]. This feature allows abuse fighters to access information about IP addresses. Please check our update on [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/IP Info feature#April|how to find and use the tool]]. Please share your feedback using a link you will be given within the tool itself. '''Changes later this week''' * There is no new MediaWiki version this week. * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-07-12|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s3.dblist targeted wikis]). '''Future changes''' * The Beta Feature for [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] will be updated throughout July. Discussions will look different. You can see [[mw:Special:MyLanguage/Talk pages project/Usability/Prototype|some of the proposed changes]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/28|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W28"/> 19:24, 11 July 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23502519 --> == Tech News: 2022-29 == <section begin="technews-2022-W29"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/29|Translations]] are available. '''Problems''' * The feature on mobile web for [[mw:Special:MyLanguage/Extension:NearbyPages|Nearby Pages]] was missing last week. It will be fixed this week. [https://phabricator.wikimedia.org/T312864] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.21|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-07-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-07-20|en}}. It will be on all wikis from {{#time:j xg|2022-07-21|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). '''Future changes''' * The [[mw:Technical_decision_making/Forum|Technical Decision Forum]] is seeking [[mw:Technical_decision_making/Community_representation|community representatives]]. You can apply on wiki or by emailing <span class="mw-content-ltr" lang="en" dir="ltr">TDFSupport@wikimedia.org</span> before 12 August. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/29|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W29"/> 22:59, 18 July 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23517957 --> == Tech News: 2022-30 == <section begin="technews-2022-W30"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/30|Translations]] are available. '''Recent changes''' * The <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wikibooks.org/ www.wikibooks.org]</span> and <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wikiquote.org/ www.wikiquote.org]</span> portal pages now use an automated update system. Other [[m:Project_portals|project portals]] will be updated over the next few months. [https://phabricator.wikimedia.org/T273179] '''Problems''' * Last week, some wikis were in read-only mode for a few minutes because of an emergency switch of their main database ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s7.dblist targeted wikis]). [https://phabricator.wikimedia.org/T313383] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.22|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-07-26|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-07-27|en}}. It will be on all wikis from {{#time:j xg|2022-07-28|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * The external link icon will change slightly in the skins Vector legacy and Vector 2022. The new icon uses simpler shapes to be more recognizable on low-fidelity screens. [https://phabricator.wikimedia.org/T261391] * Administrators will now see buttons on user pages for "{{int:changeblockip}}" and "{{int:unblockip}}" instead of just "{{int:blockip}}" if the user is already blocked. [https://phabricator.wikimedia.org/T308570] '''Future meetings''' * The next [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/Talk to Web|open meeting with the Web team]] about Vector (2022) will take place tomorrow (26 July). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/30|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W30"/> 19:27, 25 July 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23545370 --> == Tech News: 2022-31 == <section begin="technews-2022-W31"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/31|Translations]] are available. '''Recent changes''' * Improved [[m:Special:MyLanguage/Help:Displaying_a_formula#Phantom|LaTeX capabilities for math rendering]] are now available in the wikis thanks to supporting <bdi lang="zxx" dir="ltr"><code>Phantom</code></bdi> tags. This completes part of [[m:Community_Wishlist_Survey_2022/Editing/Missing_LaTeX_capabilities_for_math_rendering|the #59 wish]] of the 2022 Community Wishlist Survey. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-08-02|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-08-03|en}}. It will be on all wikis from {{#time:j xg|2022-08-04|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * The [[mw:Special:MyLanguage/Help:Extension:WikiEditor/Realtime_Preview|Realtime Preview]] will be available as a Beta Feature on wikis in [https://noc.wikimedia.org/conf/highlight.php?file=dblists%2Fgroup0.dblist Group 0]. This feature was built in order to fulfill [[m:Special:MyLanguage/Community_Wishlist_Survey_2021/Real_Time_Preview_for_Wikitext|one of the Community Wishlist Survey proposals]]. '''Future changes''' * The Beta Feature for [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] will be updated throughout August. Discussions will look different. You can see [[mw:Special:MyLanguage/Talk pages project/Usability/Prototype|some of the proposed changes]]. '''Future meetings''' * This week, three meetings about [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Vector (2022)]] with live interpretation will take place. On Tuesday, interpretation in Russian will be provided. On Thursday, meetings for Arabic and Spanish speakers will take place. [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/Talk to Web|See how to join]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W31"/> 21:21, 1 August 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23615613 --> == Tech News: 2022-32 == <section begin="technews-2022-W32"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/32|Translations]] are available. '''Recent changes''' * [[:m:Special:MyLanguage/Meta:GUS2Wiki/Script|GUS2Wiki]] copies the information from [[{{#special:GadgetUsage}}]] to an on-wiki page so you can review its history. If your project isn't already listed on the [[d:Q113143828|Wikidata entry for Project:GUS2Wiki]] you can either run GUS2Wiki yourself or [[:m:Special:MyLanguage/Meta:GUS2Wiki/Script#Opting|make a request to receive updates]]. [https://phabricator.wikimedia.org/T121049] '''Changes later this week''' * There is no new MediaWiki version this week. * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-08-09|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist targeted wikis]) and on {{#time:j xg|2022-08-11|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s2.dblist targeted wikis]). '''Future meetings''' * The [[wmania:Special:MyLanguage/Hackathon|Wikimania Hackathon]] will take place online from August 12–14. Don't miss [[wmania:Special:MyLanguage/Hackathon/Schedule|the pre-hacking showcase]] to learn about projects and find collaborators. Anyone can [[phab:/project/board/6030/|propose a project]] or [[wmania:Special:MyLanguage/Hackathon/Schedule|host a session]]. [[wmania:Special:MyLanguage/Hackathon/Newcomers|Newcomers are welcome]]! '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W32"/> 19:50, 8 August 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23627807 --> == Tech News: 2022-33 == <section begin="technews-2022-W33"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/33|Translations]] are available. '''Recent changes''' * The Persian (Farsi) Wikipedia community decided to block IP editing from October 2021 to April 2022. The Wikimedia Foundation's Product Analytics team tracked the impact of this change. [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/IP Editing Restriction Study/Farsi Wikipedia|An impact report]] is now available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.25|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-08-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-08-17|en}}. It will be on all wikis from {{#time:j xg|2022-08-18|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-08-16|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s1.dblist targeted wikis]) and on {{#time:j xg|2022-08-18|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s8.dblist targeted wikis]). * The [[mw:Special:MyLanguage/Help:Extension:WikiEditor/Realtime_Preview|Realtime Preview]] will be available as a Beta Feature on wikis in [https://noc.wikimedia.org/conf/highlight.php?file=dblists%2Fgroup1.dblist Group 1]. This feature was built in order to fulfill [[m:Special:MyLanguage/Community_Wishlist_Survey_2021/Real_Time_Preview_for_Wikitext|one of the Community Wishlist Survey proposals]]. '''Future changes''' * The Beta Feature for [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] will be updated throughout August. Discussions will look different. You can see [[mw:Special:MyLanguage/Talk pages project/Usability/Prototype|some of the proposed changes]]. [https://www.mediawiki.org/wiki/Talk_pages_project/Usability#4_August_2022][https://www.mediawiki.org/wiki/Talk_pages_project/Usability#Phase_1:_Topic_containers][https://phabricator.wikimedia.org/T312672] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W33"/> 21:08, 15 August 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23658001 --> == Tech News: 2022-34 == <section begin="technews-2022-W34"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/34|Translations]] are available. '''Recent changes''' * Two problems with [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] maps have been fixed. Maps are no longer shown as empty when a geoline was created via VisualEditor. Geolines consisting of points with QIDs (e.g., subway lines) are no longer shown with pushpins. [https://phabricator.wikimedia.org/T292613][https://phabricator.wikimedia.org/T308560] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.26|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-08-23|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-08-24|en}}. It will be on all wikis from {{#time:j xg|2022-08-25|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-08-25|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s4.dblist targeted wikis]). * The colours of links and visited links will change. This is to make the difference between links and other text more clear. [https://phabricator.wikimedia.org/T213778] '''Future changes''' * The new [{{int:discussiontools-topicsubscription-button-subscribe}}] button [[mw:Talk pages project/Notifications#12 August 2022|helps newcomers get answers]]. The Editing team is enabling this tool everywhere. You can turn it off in [[Special:Preferences#mw-prefsection-editing-discussion|your preferences]]. [https://phabricator.wikimedia.org/T284489] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W34"/> 00:12, 23 August 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23675501 --> == Tech News: 2022-35 == <section begin="technews-2022-W35"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/35|Translations]] are available. '''Recent changes''' * The [[mw:Special:MyLanguage/Help:Extension:WikiEditor/Realtime_Preview|Realtime Preview]] is available as a Beta Feature on wikis in [https://noc.wikimedia.org/conf/highlight.php?file=dblists%2Fgroup2.dblist Group 2]. This feature was built in order to fulfill [[m:Special:MyLanguage/Community_Wishlist_Survey_2021/Real_Time_Preview_for_Wikitext|one of the Community Wishlist Survey proposals]]. Please note that when this Beta feature is enabled, it may cause conflicts with some wiki-specific Gadgets. '''Problems''' * In recent months, there have been inaccurate numbers shown for various [[{{#special:statistics}}]] at Commons, Wikidata, and English Wikipedia. This has now been fixed. [https://phabricator.wikimedia.org/T315693] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.27|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-08-30|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-08-31|en}}. It will be on all wikis from {{#time:j xg|2022-09-01|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-08-30|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s6.dblist targeted wikis]) and on {{#time:j xg|2022-09-01|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s7.dblist targeted wikis]). '''Future changes''' * The Wikimedia Foundation wants to improve how Wikimedia communities report harmful incidents by building the [[m:Special:MyLanguage/Private Incident Reporting System|Private Incident Reporting System (PIRS)]] to make it easy and safe for users to make reports. You can leave comments on the talk page, by answering the [[m:Special:MyLanguage/Private Incident Reporting System#Phase 1|questions provided]]. If you have ever faced a harmful situation that you wanted to report/reported, join a PIRS interview to share your experience. To sign up [[m:Special:EmailUser/MAna_(WMF)|please email]] <span class="mw-content-ltr" lang="en" dir="ltr">[[m:User:MAna (WMF)|Madalina Ana]]</span>. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W35"/> 23:05, 29 August 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23725814 --> == Tech News: 2022-36 == <section begin="technews-2022-W36"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/36|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.39/wmf.28|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-09-06|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-09-07|en}}. It will be on all wikis from {{#time:j xg|2022-09-08|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-09-06|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s1.dblist targeted wikis]) and on {{#time:j xg|2022-09-08|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s3.dblist targeted wikis]). * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] On Special pages that only have one tab, the tab-bar's row will be hidden in the Vector-2022 skin to save space. The row will still show if Gadgets use it. Gadgets that currently append directly to the CSS id of <bdi lang="zxx" dir="ltr"><code>#p-namespaces</code></bdi> should be updated to use the <bdi lang="zxx" dir="ltr"><code>[[mw:ResourceLoader/Core_modules#addPortletLink|mw.util.addPortletLink]]</code></bdi> function instead. Gadgets that style this id should consider also targeting <bdi lang="zxx" dir="ltr"><code>#p-associated-pages</code></bdi>, the new id for this row. [[phab:T316908|Examples are available]]. [https://phabricator.wikimedia.org/T316908][https://phabricator.wikimedia.org/T313409] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W36"/> 23:22, 5 September 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23757743 --> == Tech News: 2022-37 == <section begin="technews-2022-W37"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/37|Translations]] are available. '''Recent changes''' * The search servers have been upgraded to a new major version. If you notice any issues with searching, please report them on [[phab:project/view/1849/|Phabricator]]. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/message/XPCTYYTN67FVFKN6XOHULJVGUO44J662] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.1|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-09-13|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-09-14|en}}. It will be on all wikis from {{#time:j xg|2022-09-15|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[mw:Special:MyLanguage/Extension:SyntaxHighlight|Syntax highlighting]] is now tracked as an [[mw:Special:MyLanguage/Manual:$wgExpensiveParserFunctionLimit|expensive parser function]]. Only 500 expensive function calls can be used on a single page. Pages that exceed the limit are added to a [[:Category:{{MediaWiki:expensive-parserfunction-category}}|tracking category]]. [https://phabricator.wikimedia.org/T316858] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W37"/> 01:50, 13 September 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23787318 --> == Tech News: 2022-38 == <section begin="technews-2022-W38"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/38|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Two database fields in the <bdi lang="zxx" dir="ltr"><code><nowiki>templatelinks</nowiki></code></bdi> table are now being dropped: <bdi lang="zxx" dir="ltr"><code><nowiki>tl_namespace</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>tl_title</nowiki></code></bdi>. Any queries that rely on these fields need to be changed to use the new normalization field called <bdi lang="zxx" dir="ltr"><code><nowiki>tl_target_id</nowiki></code></bdi>. See <span class="mw-content-ltr" lang="en" dir="ltr">[[phab:T299417|T299417]]</span> for more information. This is part of [[w:Database normalization|normalization]] of links tables. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/message/U2U6TXIBABU3KDCVUOITIGI5OJ4COBSW/][https://www.mediawiki.org/wiki/User:ASarabadani_(WMF)/Database_for_devs_toolkit/Concepts/Normalization] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.2|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-09-20|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-09-21|en}}. It will be on all wikis from {{#time:j xg|2022-09-22|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * In [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] maps, you can use icons on markers for common points of interest. On Tuesday, the [[mw:Special:MyLanguage/Help:Extension:Kartographer/Icons|previous icon set]] will be updated to [https://de.wikipedia.beta.wmflabs.org/wiki/Hilfe:Extension:Kartographer/Icons version maki 7.2]. That means, around 100 new icons will be available. Additionally, all existing icons were updated for clarity and to make them work better in international contexts. [https://phabricator.wikimedia.org/T302861][https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation#Update_maki_icons] '''Future changes''' * In a [[m:Content_Partnerships_Hub/Software/Volunteer_developers_discussion_at_Wikimania_2022|group discussion at Wikimania]], more than 30 people talked about how to make content partnership software in the Wikimedia movement more sustainable. What kind of support is acceptable for volunteer developers? Read the summary and [[m:Talk:Content Partnerships Hub/Software/Volunteer developers discussion at Wikimania 2022|leave your feedback]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W38"/> <span class="mw-content-ltr" lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</span> 22:16, 19 September 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23826293 --> == Tech News: 2022-39 == <section begin="technews-2022-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/39|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Parsoid clients should be updated to allow for space-separated multi-values in the <bdi lang="en" dir="ltr"><code>rel</code></bdi> attribute of links. Further details are in <bdi lang="en" dir="ltr">[[phab:T315209|T315209]]</bdi>. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.3|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-09-27|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-09-28|en}}. It will be on all wikis from {{#time:j xg|2022-09-29|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[mw:Special:MyLanguage/VisualEditor/Diffs|Visual diffs]] will become available to all users, except at the Wiktionaries and Wikipedias. [https://phabricator.wikimedia.org/T314588] * [[mw:Special:MyLanguage/Help:DiscussionTools#Mobile|Talk pages on the mobile site]] will change at the Arabic, Bangla, Chinese, French, Haitian Creole, Hebrew, Korean, and Vietnamese Wikipedias. They should be easier to use and provide more information. [https://phabricator.wikimedia.org/T318302] [https://www.mediawiki.org/wiki/Talk_pages_project/Mobile] * In the [[mw:Lua/Scripting|{{ns:828}}]] namespace, pages ending with <bdi lang="en" dir="ltr"><code>.json</code></bdi> will be treated as JSON, just like they already are in the {{ns:2}} and {{ns:8}} namespaces. [https://phabricator.wikimedia.org/T144475] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W39"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:30, 27 September 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23860085 --> == Tech News: 2022-40 == <section begin="technews-2022-W40"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/40|Translations]] are available. '''Recent changes''' * [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] maps can now show geopoints from Wikidata, via QID or SPARQL query. Previously, this was only possible for geoshapes and geolines. [https://phabricator.wikimedia.org/T307695] [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation/Geopoints_via_QID] * The [[m:Special:MyLanguage/Coolest_Tool_Award|Coolest Tool Award 2022]] is looking for nominations. You can recommend tools until 12 October. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.4|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-10-04|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-10-05|en}}. It will be on all wikis from {{#time:j xg|2022-10-06|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[mw:Special:MyLanguage/Help:DiscussionTools#Mobile|Talk pages on the mobile site]] will change at the Arabic, Bangla, Chinese, French, Haitian Creole, Hebrew, Korean, and Vietnamese Wikipedias. They should be easier to use and provide more information. (Last week's release was delayed) [https://phabricator.wikimedia.org/T318302] [https://www.mediawiki.org/wiki/Talk_pages_project/Mobile] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The <bdi lang="zxx" dir="ltr"><code>scribunto-console</code></bdi> API module will require a [[mw:Special:MyLanguage/API:Tokens|CSRF token]]. This module is documented as internal and use of it is not supported. [[phab:T212071|[5]]] * The Vector 2022 skin will become the default across the smallest Wikimedia projects. [[mw:Special:MyLanguage/Reading/Web/Desktop_Improvements#Deployment_plan_and_timeline|Learn more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W40"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:23, 4 October 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23885489 --> == Tech News: 2022-41 == <section begin="technews-2022-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/41|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-10-11|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-10-12|en}}. It will be on all wikis from {{#time:j xg|2022-10-13|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * On some wikis, [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] maps in full size view will be able to display nearby articles. After a feedback period, more wikis will follow. [https://phabricator.wikimedia.org/T316782][https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation/Nearby_articles] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W41"/> 14:08, 10 October 2022 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23912412 --> == Tech News: 2022-42 == <section begin="technews-2022-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/42|Translations]] are available. '''Recent changes''' * The recently implemented feature of [[phab:T306883|article thumbnails in Special:Search]] will be limited to Wikipedia projects only. Further details are in [[phab:T320510|T320510]]. [https://www.mediawiki.org/wiki/Special:MyLanguage/Structured_Data_Across_Wikimedia/Search_Improvements] * A bug that caused problems in loading article thumbnails in Special:Search has been fixed. Further details are in [[phab:T320406|T320406]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.6|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-10-18|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-10-19|en}}. It will be on all wikis from {{#time:j xg|2022-10-20|en}} ([[mw:MediaWiki 1.39/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Lua module authors can use <bdi lang="zxx" dir="ltr"><code>[[mw:Special:MyLanguage/Extension:Scribunto/Lua_reference_manual#mw.loadJsonData|mw.loadJsonData()]]</code></bdi> to load data from JSON pages. [https://phabricator.wikimedia.org/T217500] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Lua module authors can enable <bdi lang="zxx" dir="ltr"><code>[[mw:Special:MyLanguage/Extension:Scribunto/Lua_reference_manual#Strict_library|require( "strict" )]]</code></bdi> to add errors for some possible code problems. This replaces "[[wikidata:Q16748603|Module:No globals]]" on most wikis. [https://phabricator.wikimedia.org/T209310] '''Future changes''' * The [[Special:Preferences#mw-prefsection-betafeatures|Beta Feature]] for [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] will be updated at most wikis. The "{{int:discussiontools-replylink}}" button will look different after this change. [https://phabricator.wikimedia.org/T320683] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W42"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:46, 17 October 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23943992 --> == Tech News: 2022-43 == <section begin="technews-2022-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/43|Translations]] are available. '''Recent changes''' * There have been some minor visual fixes in Special:Search, regarding audio player alignment and image placeholder height. Further details are in [[phab:T319230|T319230]]. * On Wikipedias, a new [[Special:Preferences#mw-prefsection-searchoptions|preference]] has been added to hide article thumbnails in Special:Search. Full details are in [[phab:T320337|T320337]]. '''Problems''' * Last week, three wikis ({{int:project-localized-name-frwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-jawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ruwiki/en}}) had read-only access for 25 minutes. This was caused by a hardware problem. [https://phabricator.wikimedia.org/T320990] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-10-25|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-10-26|en}}. It will be on all wikis from {{#time:j xg|2022-10-27|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-10-25|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist targeted wikis]) and on {{#time:j xg|2022-10-27|en}} at 7:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s4.dblist targeted wikis]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-aswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-banwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-barwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bat smgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bclwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-be x oldwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bhwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-biwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bjnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bmwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bpywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-brwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bugwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bxrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-idwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T304549] * Starting on Wednesday October 26, 2022, the list of mentors will be upgraded [[d:Q14339834 | at wikis where Growth mentorship is available]]. The mentorship system will continue to work as it does now. The signup process [[mw:Special:MyLanguage/Growth/Communities/How to configure the mentors' list#add|will be replaced]], and a new management option will be provided. Also, this change simplifies [[mw:Special:MyLanguage/Growth/Communities/How to configure the mentors' list#create|the creation of mentorship systems at Wikipedias]]. [https://phabricator.wikimedia.org/T314858][https://phabricator.wikimedia.org/T310905][https://www.mediawiki.org/wiki/Special:MyLanguage/Growth/Structured_mentor_list] * Pages with titles that start with a lower-case letter according to Unicode 11 will be renamed or deleted. There is a list of affected pages at <bdi lang="en" dir="ltr">[[m:Unicode 11 case map migration]]</bdi>. More information can be found at [[phab:T292552|T292552]]. * The Vector 2022 skin will become the default across the smallest Wikipedias. [[mw:Special:MyLanguage/Reading/Web/Desktop_Improvements#smallest-1|Learn more]]. '''Future changes''' * The [[mw:Special:MyLanguage/Talk pages project/Replying|Reply tool]] and [[mw:Special:MyLanguage/Talk pages project/New discussion|New Topic tool]] will soon get a [[mw:Special:MyLanguage/VisualEditor/Special characters|special characters menu]]. [https://phabricator.wikimedia.org/T249072] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W43"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:22, 24 October 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23975411 --> == Tech News: 2022-44 == <section begin="technews-2022-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/44|Translations]] are available. '''Recent changes''' * When using keyboard navigation on a [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] map, the focus will become more visible. [https://phabricator.wikimedia.org/T315997] * In {{#special:RecentChanges}}, you can now hide the log entries for new user creations with the filter for "{{int:rcfilters-filter-newuserlogactions-label}}". [https://phabricator.wikimedia.org/T321155] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.8|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-11-01|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-11-02|en}}. It will be on all wikis from {{#time:j xg|2022-11-03|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * The [[mw:Special:MyLanguage/Help:Extension:Kartographer|maps dialog]] in VisualEditor now has some help texts. [https://phabricator.wikimedia.org/T318818] * It is now possible to select the language of a [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] map in VisualEditor via a dropdown menu. [https://phabricator.wikimedia.org/T318817] * It is now possible to add a caption to a [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] map in VisualEditor. [https://phabricator.wikimedia.org/T318815] * It is now possible to hide the frame of a [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] map in VisualEditor. [https://phabricator.wikimedia.org/T318813] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W44"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:15, 31 October 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=23977539 --> == Tech News: 2022-45 == <section begin="technews-2022-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/45|Translations]] are available. '''Recent changes''' * An updated version of the [[m:Special:MyLanguage/EventCenter/Registration|Event Registration]] tool is now available for testing at [[testwiki:|testwiki]] and [[test2wiki:| test2wiki]]. The tool provides features for event organizers and participants. Your feedback is welcome at our [[m:Talk:Campaigns/Foundation Product Team/Registration|project talkpage]]. More information about [[m:Campaigns/Foundation Product Team/Registration|the project]] is available. [https://phabricator.wikimedia.org/T318592] '''Problems''' * Twice last week, for about 45 minutes, some files and thumbnails failed to load and uploads failed, mostly for logged-in users. The cause is being investigated and an incident report will be available soon. '''Changes later this week''' * There is no new MediaWiki version this week. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W45"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:32, 8 November 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24001035 --> == Tech News: 2022-46 == <section begin="technews-2022-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/46|Translations]] are available. '''Recent changes''' * At Wikidata, an interwiki link can now point to a redirect page if certain conditions are met. This new feature is called [[wikidata:Special:MyLanguage/Wikidata:Sitelinks_to_redirects|sitelinks to redirects]]. It is needed when one wiki uses one page to cover multiple concepts but another wiki uses more pages to cover the same concepts. Your [[wikidata:Special:MyLanguage/Wikidata talk:Sitelinks to redirects|feedback on the talkpage]] of the new proposed guideline is welcome. [https://phabricator.wikimedia.org/T278962] * The <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wikinews.org/ www.wikinews.org]</span>, <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wikiversity.org/ www.wikiversity.org]</span>, and <span class="mw-content-ltr" lang="en" dir="ltr">[https://www.wikivoyage.org/ www.wikivoyage.org]</span> portal pages now use an automated update system. [https://phabricator.wikimedia.org/T273179] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.10|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-11-15|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-11-16|en}}. It will be on all wikis from {{#time:j xg|2022-11-17|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * There will be a new link to directly "Edit template data" on Template pages. [https://phabricator.wikimedia.org/T316759] '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Wikis where mobile [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] are enabled ([[mw:Special:MyLanguage/Talk pages project/Deployment Status|these ones]]) will soon use full CSS styling to display any templates that are placed at the top of talk pages. To adapt these “talk page boxes” for narrow mobile devices you can use media queries, such as in [https://en.wikipedia.org/w/index.php?title=Module:Message_box/tmbox.css&oldid=1097618699#L-69 this example]. [https://phabricator.wikimedia.org/T312309] * Starting in January 2023, [[m:Special:MyLanguage/Community Tech|Community Tech]] will be [[m:Special:MyLanguage/Community Wishlist Survey/Updates/2023 Changes Update|running the Community Wishlist Survey (CWS) every two years]]. This means that in 2024, there will be no new proposals or voting. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W46"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:54, 14 November 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24071290 --> == Tech News: 2022-47 == <section begin="technews-2022-W47"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/47|Translations]] are available. '''Recent changes''' * The display of non-free media in the search bar and for article thumbnails in Special:Search has been deactivated. Further details are in [[phab:T320661|T320661]]. '''Changes later this week''' * There is no new MediaWiki version this week. * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-11-22|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s2.dblist targeted wikis]) and on {{#time:j xg|2022-11-24|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s7.dblist targeted wikis]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/47|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W47"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:22, 21 November 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24071290 --> == Tech News: 2022-48 == <section begin="technews-2022-W48"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/48|Translations]] are available. '''Recent changes''' * A new preference, “Enable limited width mode”, has been added to the [[Special:Preferences#mw-prefsection-rendering|Vector 2022 skin]]. The preference is also available as a toggle on every page if your monitor is 1600 pixels or wider. It allows for increasing the width of the page for logged-out and logged-in users. [https://phabricator.wikimedia.org/T319449] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.12|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-11-29|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-11-30|en}}. It will be on all wikis from {{#time:j xg|2022-12-01|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2022-11-29|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s3.dblist targeted wikis]) and on {{#time:j xg|2022-12-01|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s1.dblist targeted wikis]). * Mathematical formulas shown in SVG image format will no longer have PNG fall-backs for browsers that don't support them. This is part of work to modernise the generation system. Showing only PNG versions was the default option until in February 2018. [https://lists.wikimedia.org/hyperkitty/list/wikimedia-l@lists.wikimedia.org/message/3BGOKWJIZGL4TC4HJ22ICRU2SEPWGCR4/][https://phabricator.wikimedia.org/T311620][https://phabricator.wikimedia.org/T186327] * On [[phab:P40224|some wikis]] that use flagged revisions, [[mw:Special:MyLanguage/Help:Extension:FlaggedRevs#Special:Contributions|a new checkbox will be added]] to Special:Contributions that enables you to see only the [[mw:Special:MyLanguage/Help:Pending changes|pending changes]] by a user. [https://phabricator.wikimedia.org/T321445] '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] How media is structured in the parser's HTML output will change early next week at [https://wikitech.wikimedia.org/wiki/Deployments/Train#Wednesday group1 wikis] (but not Wikimedia Commons or Meta-Wiki). This change improves the accessibility of content, and makes it easier to write related CSS. You may need to update your site-CSS, or userscripts and gadgets. There are [[mw:Special:MyLanguage/Parsoid/Parser_Unification/Media_structure/FAQ|details on what code to check, how to update the code, and where to report any related problems]]. [https://phabricator.wikimedia.org/T314318] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/48|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W48"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:03, 28 November 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24114342 --> == Tech News: 2022-49 == <section begin="technews-2022-W49"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/49|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The Wikisources use a tool called ProofreadPage. ProofreadPage uses OpenSeadragon which is an open source tool. The OpenSeadragon JavaScript API has been significantly re-written to support dynamically loading images. The functionality provided by the older version of the API should still work but it is no longer supported. User scripts and gadgets should migrate over to the newer version of the API. The functionality provided by the newer version of the API is [[mw:Extension:Proofread_Page/Page_viewer#JS_API|documented on MediaWiki]]. [https://phabricator.wikimedia.org/T308098][https://www.mediawiki.org/wiki/Extension:Proofread_Page/Edit-in-Sequence] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.13|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-12-06|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-12-07|en}}. It will be on all wikis from {{#time:j xg|2022-12-08|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/49|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W49"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:41, 6 December 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24151590 --> == Tech News: 2022-50 == <section begin="technews-2022-W50"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/50|Translations]] are available. '''Recent changes''' * An [[mw:Special:MyLanguage/Talk pages project/Mobile|A/B test has begun]] at 15 Wikipedias for [[mw:Special:MyLanguage/Help:DiscussionTools#Mobile|DiscussionTools on mobile]]. Half of the editors on the [[mw:Reading/Web/Mobile|mobile web site]] will have access to the {{int:discussiontools-replybutton}} tool and other features. [https://phabricator.wikimedia.org/T321961] * The character <code>=</code> cannot be used in new usernames, to make usernames work better with templates. Existing usernames are not affected. [https://phabricator.wikimedia.org/T254045] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.14|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2022-12-13|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2022-12-14|en}}. It will be on all wikis from {{#time:j xg|2022-12-15|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The HTML markup used by [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] to [[mw:Special:MyLanguage/Talk_pages_project/Usability#Phase_1:_Topic_containers|show discussion metadata below section headings]] will be inserted after these headings, not inside of them. This change improves the accessibility of discussion pages for screen reader software. [https://phabricator.wikimedia.org/T314714] '''Events''' * The fourth edition of the [[m:Special:MyLanguage/Coolest_Tool_Award|Coolest Tool Award]] will happen online on [https://zonestamp.toolforge.org/1671210002 Friday 16 December 2022 at 17:00 UTC]! The event will be live-streamed on YouTube in the [https://www.youtube.com/user/watchmediawiki MediaWiki channel] and added to Commons afterwards. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/50|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W50"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:34, 12 December 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24216570 --> == Tech News: 2022-51 == <section begin="technews-2022-W51"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2022/51|Translations]] are available. '''Tech News''' * Because of the [[w:en:Christmas and holiday season|holidays]] the next issue of Tech News will be sent out on 9 January 2023. '''Recent changes''' * On a user's contributions page, you can filter it for edits with a tag like 'reverted'. Now, you can also filter for all edits that are not tagged like that. This was part of a Community Wishlist 2022 request. [https://phabricator.wikimedia.org/T119072] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] A new function has been used for gadget developers to add content underneath the title on article pages. This is considered a stable API that should work across all skins. [[mw:Special:MyLanguage/ResourceLoader/Core_modules#addSubtitle|Documentation is available]]. [https://phabricator.wikimedia.org/T316830] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] [[test2wiki:|One of our test wikis]] is now being served from a new infrastructure powered by [[w:Kubernetes|Kubernetes]] ([[wikitech:MediaWiki On Kubernetes|read more]]). More Wikis will switch to this new infrastructure in early 2023. Please test and let us know of any issues. [https://phabricator.wikimedia.org/T290536] '''Problems''' * Last week, all wikis had no edit access for 9 minutes. This was caused by a database problem. [https://wikitech.wikimedia.org/wiki/Incidents/2022-12-13_sessionstore] '''Changes later this week''' * There is no new MediaWiki version this week or next week. * The word "{{int:discussiontools-replybutton}}" is very short in some languages, such as Arabic ("<bdi lang="ar">ردّ</bdi>"). This makes the {{int:discussiontools-preference-label}} button on talk pages difficult to use. An arrow icon will be added to those languages. This will only be visible to editors who have the [[Special:Preferences#mw-prefsection-betafeatures|Beta Feature]] turned on. [https://www.mediawiki.org/wiki/Talk_pages_project/Usability#Status] [https://phabricator.wikimedia.org/T323537] '''Future changes''' * Edits can be automatically "tagged" by the system software or the {{int:Abusefilter}} system. Those tags link to a help page about the tags. Soon they will also link to Recent Changes to let you see other edits tagged this way. This was a Community Wishlist 2022 request. [https://phabricator.wikimedia.org/T301063] * The Trust & Safety tools team [[m:Special:MyLanguage/Private Incident Reporting System/Timeline and Updates|have shared new plans]] for building the Private Incident Reporting System. The system will make it easier for editors to ask for help if they are harassed or abused. * [[m:Special:MyLanguage/Community Wishlist Survey 2021/Real Time Preview for Wikitext|Realtime Preview for Wikitext]] is coming out of beta as an enabled feature for every user of the 2010 Wikitext [[mw:Special:MyLanguage/Editor|editor]] in the week of January 9, 2023. It will be available to use via the toolbar in the 2010 Wikitext editor. The feature was the 4th most popular wish of the Community Wishlist Survey 2021. '''Events''' * You can now [[mw:Special:MyLanguage/Wikimedia Hackathon 2023/Participate|register for the Wikimedia Hackathon 2023]], taking place on May 19–21 in Athens, Greece. You can also apply for a scholarship until January 14th. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2022/51|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2022-W51"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:00, 20 December 2022 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24258101 --> == Tech News: 2023-02 == <section begin="technews-2023-W02"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/02|Translations]] are available. '''Recent changes''' * You can use tags to filter edits in the recent changes feed or on your watchlist. You can now use tags to filter out edits you don't want to see. Previously you could only use tags to focus on the edits with those tags. [https://phabricator.wikimedia.org/T174349] * [[Special:WhatLinksHere|Special:WhatLinksHere]] shows all pages that link to a specific page. There is now a [https://wlh.toolforge.org prototype] for how to sort those pages alphabetically. You can see the discussion in the [[phab:T4306|Phabricator ticket]]. * You can now use the [[mw:Special:MyLanguage/Extension:Thanks|thanks]] function on your watchlist and the user contribution page. [https://phabricator.wikimedia.org/T51541] * A wiki page can be moved to give it a new name. You can now get a dropdown menu with common reasons when you move a page. This is so you don't have to write the explanation every time. [https://phabricator.wikimedia.org/T325257] * [[m:Special:MyLanguage/Matrix.org|Matrix]] is a chat tool. You can now use <code>matrix:</code> to create Matrix links on wiki pages. [https://phabricator.wikimedia.org/T326021] * You can filter out translations when you look at the recent changes on multilingual wikis. This didn't hide translation pages. You can now also hide subpages which are translation pages. [https://phabricator.wikimedia.org/T233493] '''Changes later this week''' * [[m:Special:MyLanguage/Real Time Preview for Wikitext|Realtime preview for wikitext]] is a tool which lets editors preview the page when they edit wikitext. It will be enabled for all users of the 2010 wikitext editor. You will find it in the editor toolbar. * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] Some wikis will be in read-only for a few minutes because of a switch of their main database. It will be performed on {{#time:j xg|2023-01-10|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist targeted wikis]) and on {{#time:j xg|2023-01-12|en}} at 07:00 UTC ([https://noc.wikimedia.org/conf/highlight.php?file=dblists/s6.dblist targeted wikis]). * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.18|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-01-10|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-01-11|en}}. It will be on all wikis from {{#time:j xg|2023-01-12|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/02|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W02"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:07, 10 January 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24342971 --> == Tech News: 2023-03 == <section begin="technews-2023-W03"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/03|Translations]] are available. '''Problems''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The URLs in "{{int:last}}" links on page history now contain <bdi lang="zxx" dir="ltr"><code><nowiki>diff=prev&oldid=[revision ID]</nowiki></code></bdi> in place of <bdi lang="zxx" dir="ltr"><code><nowiki>diff=[revision ID]&oldid=[revision ID]</nowiki></code></bdi>. This is to fix a problem with links pointing to incorrect diffs when history was filtered by a tag. Some user scripts may break as a result of this change. [https://phabricator.wikimedia.org/T243569] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.19|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-01-17|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-01-18|en}}. It will be on all wikis from {{#time:j xg|2023-01-19|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * Some [[mw:Special:MyLanguage/Talk pages project/Usability|changes to the appearance of talk pages]] have only been available on <code>{{ns:1}}:</code> and <code>{{ns:3}}:</code> namespaces. These will be extended to other talk namespaces, such as <code>{{ns:5}}:</code>. They will continue to be unavailable in non-talk namespaces, including <code>{{ns:4}}:</code> pages (e.g., at the Village Pump). You can [[Special:Preferences#mw-prefsection-editing-discussion|change your preferences]] ([[Special:Preferences#mw-prefsection-betafeatures|beta feature]]). [https://phabricator.wikimedia.org/T325417] *On Wikisources, when an image is zoomed or panned in the Page: namespace, the same zoom and pan settings will be remembered for all Page: namespace pages that are linked to a particular Index: namespace page. [https://gerrit.wikimedia.org/r/c/mediawiki/extensions/ProofreadPage/+/868841] * The Vector 2022 skin will become the default for the English Wikipedia desktop users. The change will take place on January 18 at 15:00 UTC. [[:en:w:Wikipedia:Vector 2022|Learn more]]. '''Future changes''' * The 2023 edition of the [[m:Special:MyLanguage/Community Wishlist Survey 2023|Community Wishlist Survey]], which invites contributors to make technical proposals and vote for tools and improvements, starts next week on 23 January 2023 at 18:00 UTC. You can start drafting your proposals in [[m:Community Wishlist Survey/Sandbox|the CWS sandbox]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/03|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W03"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:10, 17 January 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24381020 --> == Tech News: 2023-04 == <section begin="technews-2023-W04"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/04|Translations]] are available. '''Problems''' * Last week, for ~15 minutes, all wikis were unreachable for logged-in users and non-cached pages. This was caused by a timing issue. [https://wikitech.wikimedia.org/wiki/Incidents/2023-01-17_MediaWiki] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.20|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-01-24|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-01-25|en}}. It will be on all wikis from {{#time:j xg|2023-01-26|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * If you have the Beta Feature for [[mw:Special:MyLanguage/Talk pages project|DiscussionTools]] enabled, the appearance of talk pages will add more information about discussion activity. [https://www.mediawiki.org/wiki/Special:MyLanguage/Talk_pages_project/Usability#Status][https://phabricator.wikimedia.org/T317907] * The 2023 edition of the [[m:Special:MyLanguage/Community Wishlist Survey 2023|Community Wishlist Survey]] (CWS), which invites contributors to make technical proposals and vote for tools and improvements, starts on Monday 23 January 2023 at [https://zonestamp.toolforge.org/1674496814 18:00 UTC]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/04|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W04"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:46, 23 January 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24418874 --> == Tech News: 2023-05 == <section begin="technews-2023-W05"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/05|Translations]] are available. '''Problems''' * Last week, for ~15 minutes, some users were unable to log in or edit pages. This was caused by a problem with session storage. [https://wikitech.wikimedia.org/wiki/Incidents/2023-01-24_sessionstore_quorum_issues] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.21|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-01-31|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-02-01|en}}. It will be on all wikis from {{#time:j xg|2023-02-02|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Wikis that use localized numbering schemes for references need to add new CSS. This will help to show citation numbers the same way in all reading and editing modes. If your wiki would prefer to do it yourselves, please see the [[mw:Special:MyLanguage/Parsoid/Parser Unification/Cite CSS|details and example CSS to copy from]], and also add your wiki to the list. Otherwise, the developers will directly help out starting the week of February 5. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/05|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W05"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:05, 31 January 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24455949 --> == Tech News: 2023-06 == <section begin="technews-2023-W06"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/06|Translations]] are available. '''Recent changes''' * In the [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements|Vector 2022 skin]], logged-out users using the full-width toggle will be able to see the setting of their choice even after refreshing pages or opening new ones. This only applies to wikis where Vector 2022 is the default. [https://phabricator.wikimedia.org/T321498] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.22|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-02-07|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-02-08|en}}. It will be on all wikis from {{#time:j xg|2023-02-09|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * Previously, we announced when some wikis would be in read-only for a few minutes because of a switch of their main database. These switches will not be announced any more, as the read-only time has become non-significant. Switches will continue to happen at 7AM UTC on Tuesdays and Thursdays. [https://phabricator.wikimedia.org/T292543#8568433] * Across all the wikis, in the Vector 2022 skin, logged-in users will see the page-related links such as "What links here" in a [[mw:Special:MyLanguage/Reading/Web/Desktop_Improvements/Features/Page_tools|new side menu]]. It will be displayed on the other side of the screen. This change had previously been made on Czech, English, and Vietnamese Wikipedias. [https://phabricator.wikimedia.org/T328692] *[[m:Special:MyLanguage/Community Wishlist Survey 2023|Community Wishlist Survey 2023]] will stop receiving new proposals on [https://zonestamp.toolforge.org/1675706431 Monday, 6 February 2023, at 18:00 UTC]. Proposers should complete any edits by then, to give time for [[m:Special:MyLanguage/Community_Wishlist_Survey/Help_us|translations]] and review. Voting will begin on Friday, 10 February. '''Future changes''' * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] Gadgets and user scripts will be changing to load on desktop and mobile sites. Previously they would only load on the desktop site. It is recommended that wiki administrators audit the [[MediaWiki:Gadgets-definition|gadget definitions]] prior to this change, and add <bdi lang="zxx" dir="ltr"><code>skins=…</code></bdi> for any gadgets which should not load on mobile. [https://phabricator.wikimedia.org/T328610 More details are available]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/06|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W06"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 10:21, 6 February 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24491749 --> == Tech News: 2023-07 == <section begin="technews-2023-W07"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/07|Translations]] are available. '''Problems''' * On wikis where patrolled edits are enabled, changes made to the [[mw:Special:MyLanguage/Growth/Communities/How to configure the mentors' list|mentor list]] by autopatrolled mentors are not correctly marked as patrolled. It will be fixed later this week. [https://phabricator.wikimedia.org/T328444] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-02-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-02-15|en}}. It will be on all wikis from {{#time:j xg|2023-02-16|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * The Reply tool and other parts of [[mw:Special:MyLanguage/Help:DiscussionTools#Mobile|DiscussionTools]] will be deployed for all editors using the mobile site. You can [[mw:Special:MyLanguage/Talk_pages_project/Mobile#Status_Updates|read more about this decision]]. [https://phabricator.wikimedia.org/T298060] '''Future changes''' * All wikis will be read-only for a few minutes on March 1. This is planned for [https://zonestamp.toolforge.org/1677679222 14:00 UTC]. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T328287][https://phabricator.wikimedia.org/T327920][https://wikitech.wikimedia.org/wiki/Deployments] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/07|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W07"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:48, 14 February 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24540832 --> == Tech News: 2023-08 == <section begin="technews-2023-W08"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/08|Translations]] are available. '''Problems''' * Last week, during planned maintenance of Cloud Services, unforeseen complications forced the team to turn off all tools for 2–3 hours to prevent data corruption. Work is ongoing to prevent similar problems in the future. [https://phabricator.wikimedia.org/T329535] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-02-21|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-02-22|en}}. It will be on all wikis from {{#time:j xg|2023-02-23|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). *The voting phase for the [[m:Special:MyLanguage/Community Wishlist Survey 2023|Community Wishlist Survey 2023]] ends on [https://zonestamp.toolforge.org/1677261621 24 February at 18:00 UTC]. The results of the survey will be announced on 28 February. '''Future changes''' * All wikis will be read-only for a few minutes on March 1. This is planned for [https://zonestamp.toolforge.org/1677679222 14:00 UTC]. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T328287][https://phabricator.wikimedia.org/T327920][https://wikitech.wikimedia.org/wiki/Deployments] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/08|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W08"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:57, 21 February 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24570514 --> == Tech News: 2023-09 == <section begin="technews-2023-W09"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/09|Translations]] are available. '''Problems''' * Last week, in some areas of the world, there were problems with loading pages for 20 minutes and saving edits for 55 minutes. These issues were caused by a problem with our caching servers due to unforseen events during a routine maintenance task. [https://wikitech.wikimedia.org/wiki/Incidents/2023-02-22_wiki_outage][https://wikitech.wikimedia.org/wiki/Incidents/2023-02-22_read_only] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.25|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-02-28|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-03-01|en}}. It will be on all wikis from {{#time:j xg|2023-03-02|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * All wikis will be read-only for a few minutes on March 1. This is planned for [https://zonestamp.toolforge.org/1677679222 14:00 UTC]. [https://meta.wikimedia.org/wiki/Special:MyLanguage/Tech/Server_switch] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/09|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W09"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:47, 27 February 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24634242 --> == Tech News: 2023-10 == <section begin="technews-2023-W10"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/10|Translations]] are available. '''Recent changes''' * The Community Wishlist Survey 2023 edition has been concluded. Community Tech has [[m:Special:MyLanguage/Community Wishlist Survey 2023/Results|published the results]] of the survey and will provide an update on what is next in April 2023. * On wikis which use [[mw:Special:MyLanguage/Writing_systems|LanguageConverter]] to handle multiple writing systems, articles which used custom conversion rules in the wikitext (primarily on Chinese Wikipedia) would have these rules applied inconsistently in the table of contents, especially in the Vector 2022 skin. This has now been fixed. [https://phabricator.wikimedia.org/T306862] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.26|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-03-07|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-03-08|en}}. It will be on all wikis from {{#time:j xg|2023-03-09|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * A search system has been added to the [[Special:Preferences|Preferences screen]]. This will let you find different options more easily. Making it work on mobile devices will happen soon. [https://phabricator.wikimedia.org/T313804] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/10|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W10"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:49, 6 March 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24676916 --> == Tech News: 2023-11 == <section begin="technews-2023-W11"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/11|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.40/wmf.27|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-03-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-03-15|en}}. It will be on all wikis from {{#time:j xg|2023-03-16|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-cbk_zamwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cdowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cebwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-chwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-chrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-chywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ckbwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-csbwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cuwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cvwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-itwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T304542][https://phabricator.wikimedia.org/T304550] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/11|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W11"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:20, 13 March 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24700189 --> == Tech News: 2023-12 == <section begin="technews-2023-W12"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/12|Translations]] are available. '''Problems''' * Last week, some users experienced issues loading image thumbnails. This was due to incorrectly cached images. [https://phabricator.wikimedia.org/T331820] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.1|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-03-21|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-03-22|en}}. It will be on all wikis from {{#time:j xg|2023-03-23|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] A link to the user's [[{{#special:CentralAuth}}]] page will appear on [[{{#special:Contributions}}]] — some user scripts which previously added this link may cause conflicts. This feature request was [[:m:Community Wishlist Survey 2023/Admins and patrollers/Add link to CentralAuth on Special:Contributions|voted #17 in the 2023 Community Wishlist Survey]]. * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The [[{{#special:AbuseFilter}}]] edit window will be resizable and larger by default. This feature request was [[:m:Community Wishlist Survey 2023/Anti-harassment/Make the AbuseFilter edit window resizable and larger by default|voted #80 in the 2023 Community Wishlist Survey]]. * There will be a new option for Administrators when they are unblocking a user, to add the unblocked user’s user page to their watchlist. This will work both via [[{{#special:Unblock}}]] and via the API. [https://phabricator.wikimedia.org/T257662] '''Meetings''' * You can join the next meeting with the Wikipedia mobile apps teams. During the meeting, we will discuss the current features and future roadmap. The meeting will be on [https://zonestamp.toolforge.org/1679677204 24 March at 17:00 (UTC)]. See [[mw:Special:MyLanguage/Wikimedia Apps/Office Hours|details and how to join]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/12|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W12"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:25, 21 March 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24732558 --> == Tech News: 2023-13 == <section begin="technews-2023-W13"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/13|Translations]] are available. '''Recent changes''' * The [[:mw:Special:MyLanguage/Extension:AbuseFilter|AbuseFilter]] condition limit was increased from 1000 to 2000. [https://phabricator.wikimedia.org/T309609] * [[:m:Special:MyLanguage/Global AbuseFilter#Locally disabled actions|Some Global AbuseFilter]] actions will no longer apply to local projects. [https://phabricator.wikimedia.org/T332521] * Desktop users are now able to subscribe to talk pages by clicking on the {{int:discussiontools-newtopicssubscription-button-subscribe-label}} link in the {{int:toolbox}} menu. If you subscribe to a talk page, you receive [[mw:Special:MyLanguage/Notifications|notifications]] when new topics are started on that talk page. This is separate from putting the page on your watchlist or subscribing to a single discussion. [https://phabricator.wikimedia.org/T263821] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.2|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-03-28|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-03-29|en}}. It will be on all wikis from {{#time:j xg|2023-03-30|en}} ([[mw:MediaWiki 1.40/Roadmap|calendar]]). '''Future changes''' * You will be able to choose [[mw:Special:MyLanguage/VisualEditor/Diffs|visual diffs]] on all [[m:Special:MyLanguage/Help:Page history|history pages]] at the Wiktionaries and Wikipedias. [https://phabricator.wikimedia.org/T314588] * [[File:Octicons-tools.svg|15px|link=|alt=|Advanced item]] The legacy [[mw:Mobile Content Service|Mobile Content Service]] is going away in July 2023. Developers are encouraged to switch to Parsoid or another API before then to ensure service continuity. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/4MVQQTONJT7FJAXNVOFV3WWVVMCHRINE/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/13|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W13"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:13, 28 March 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24780854 --> == Tech News: 2023-14 == <section begin="technews-2023-W14"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/14|Translations]] are available. '''Recent changes''' * The system for automatically creating categories for the [[mw:Special:MyLanguage/Extension:Babel|Babel]] extension has had several important changes and fixes. One of them allows you to insert templates for automatic category descriptions on creation, allowing you to categorize the new categories. [https://phabricator.wikimedia.org/T211665][https://phabricator.wikimedia.org/T64714][https://phabricator.wikimedia.org/T170654][https://phabricator.wikimedia.org/T184941][https://phabricator.wikimedia.org/T33074] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.3|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-04-04|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-04-05|en}}. It will be on all wikis from {{#time:j xg|2023-04-06|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Some older [[w:en:Web browser|Web browsers]] will stop being able to use [[w:en:JavaScript|JavaScript]] on Wikimedia wikis from this week. This mainly affects users of Internet Explorer 11. If you have an old web browser on your computer you can try to upgrade to a newer version. [https://phabricator.wikimedia.org/T178356] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The deprecated <bdi lang="zxx" dir="ltr"><code>jquery.hoverIntent</code></bdi> module has been removed. This module could be used by gadgets and user scripts, to create an artificial delay in how JavaScript responds to a hover event. Gadgets and user scripts should now use jQuery <bdi lang="zxx" dir="ltr"><code>hover()</code></bdi> or <bdi lang="zxx" dir="ltr"><code>on()</code></bdi> instead. Examples can be found in the [[mw:Special:MyLanguage/ResourceLoader/Migration_guide_(users)#jquery.hoverIntent|migration guide]]. [https://phabricator.wikimedia.org/T311194] * Some of the links in [[{{#special:SpecialPages}}]] will be re-arranged. There will be a clearer separation between links that relate to all users, and links related to your own user account. [https://phabricator.wikimedia.org/T333242] * You will be able to hide the [[mw:Special:MyLanguage/Talk pages project/Replying|Reply button]] in archived discussion pages with a new <bdi lang="zxx" dir="ltr"><code><nowiki>__ARCHIVEDTALK__</nowiki></code></bdi> magic word. There will also be a new <bdi lang="zxx" dir="ltr"><code>.mw-archivedtalk</code></bdi> CSS class for hiding the Reply button in individual sections on a page. [https://phabricator.wikimedia.org/T249293][https://phabricator.wikimedia.org/T295553][https://gerrit.wikimedia.org/r/c/mediawiki/extensions/DiscussionTools/+/738221] '''Future changes''' * The Vega software that creates data visualizations in pages, such as graphs, will be upgraded to the newest version in the future. Graphs that still use the very old version 1.5 syntax may stop working properly. Most existing uses have been found and updated, but you can help to check, and to update any local documentation. [[phab:T260542|Examples of how to find and fix these graphs are available]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/14|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W14"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:39, 3 April 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24820268 --> == Tech News: 2023-15 == <section begin="technews-2023-W15"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/15|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] In the visual editor, it is now possible to edit captions of images in galleries without opening the gallery dialog. This feature request was [[:m:Community Wishlist Survey 2023/Editing/Editable gallery captions in Visual Editor|voted #61 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T190224] * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] You can now receive notifications when another user edits your user page. See the "{{int:Echo-category-title-edit-user-page}}" option in [[Special:Preferences#mw-prefsection-echo|your Preferences]]. This feature request was [[:m:Community Wishlist Survey 2023/Anti-harassment/Notifications for user page edits|voted #3 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T3876] '''Problems''' * There was a problem with all types of CentralNotice banners still being shown to logged-in users even if they had [[Special:Preferences#mw-prefsection-centralnotice-banners|turned off]] specific banner types. This has now been fixed. [https://phabricator.wikimedia.org/T331671] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.4|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-04-11|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-04-12|en}}. It will be on all wikis from {{#time:j xg|2023-04-13|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-arywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-dawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-dinwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-dsbwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-eewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-elwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-emlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-eowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-etwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-euwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-extwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tumwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ffwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-fiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-fiu_vrowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-fjwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-fowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-frpwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-frrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-furwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gcrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gdwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-glwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-glkwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gomwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gotwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-guwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-gvwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T304551][https://phabricator.wikimedia.org/T308133] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/15|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W15"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:05, 10 April 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24851886 --> == Tech News: 2023-16 == <section begin="technews-2023-W16"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/16|Translations]] are available. '''Recent changes''' * You can now see [[mw:Special:MyLanguage/Help:Extension:Kartographer#Show_nearby_articles|nearby articles on a Kartographer map]] with the button for the new feature "{{int:Kartographer-sidebar-nearbybutton}}". Six wikis have been testing this feature since October. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/Geoinformation/Nearby_articles#Implementation][https://phabricator.wikimedia.org/T334079] * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The [[m:Special:GlobalWatchlist|Special:GlobalWatchlist]] page now has links for "{{int:globalwatchlist-markpageseen}}" for each entry. This feature request was [[m:Community Wishlist Survey 2023/Notifications, Watchlists and Talk Pages/Button to mark a single change as read in the global watch list|voted #161 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T334246] '''Problems''' * At Wikimedia Commons, some thumbnails have not been getting replaced correctly after a new version of the image is uploaded. This should be fixed later this week. [https://phabricator.wikimedia.org/T331138][https://phabricator.wikimedia.org/T333042] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] For the last few weeks, some external tools had inconsistent problems with logging-in with OAuth. This has now been fixed. [https://phabricator.wikimedia.org/T332650] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-04-18|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-04-19|en}}. It will be on all wikis from {{#time:j xg|2023-04-20|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/16|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W16"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:54, 18 April 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24881071 --> == Tech News: 2023-17 == <section begin="technews-2023-W17"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/17|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The date-selection menu on pages such as [[{{#special:Contributions}}]] will now show year-ranges that are in the current and past decade, instead of the current and future decade. This feature request was [[m:Community Wishlist Survey 2023/Miscellaneous/Change year range shown in date selection popup|voted #145 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T334316] '''Problems''' * Due to security issues with the [[mw:Special:MyLanguage/Extension:Graph|Graph extension]], graphs have been disabled in all Wikimedia projects. Wikimedia Foundation teams are working to respond to these vulnerabilities. [https://phabricator.wikimedia.org/T334940] * For a few days, it was not possible to save some kinds of edits on the mobile version of a wiki. This has been fixed. [https://phabricator.wikimedia.org/T334797][https://phabricator.wikimedia.org/T334799][https://phabricator.wikimedia.org/T334794] '''Changes later this week''' * All wikis will be read-only for a few minutes on April 26. This is planned for [https://zonestamp.toolforge.org/1682517653 14:00 UTC]. [https://meta.wikimedia.org/wiki/Special:MyLanguage/Tech/Server_switch] * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.6|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-04-25|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-04-26|en}}. It will be on all wikis from {{#time:j xg|2023-04-27|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''Future changes''' * The Editing team plans an A/B test for [[mw:Special:MyLanguage/Talk pages project/Usability|a usability analysis of the Talk page project]]. The [[mw:Special:MyLanguage/Talk pages project/Usability/Analysis|planned measurements are available]]. Your wiki [[phab:T332946|may be invited to participate]]. Please suggest improvements to the measurement plan at [[mw:Talk:Talk pages project/Usability|the discussion page]]. * [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2023-2024|The Wikimedia Foundation annual plan 2023-2024 draft is open for comment and input]] until May 19. The final plan will be published in July 2023 on Meta-wiki. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/17|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W17"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:03, 24 April 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24933592 --> == Tech News: 2023-18 == <section begin="technews-2023-W18"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/18|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The content attribution tools [[mw:Special:MyLanguage/Who Wrote That?|Who Wrote That?]], [[xtools:authorship|XTools Authorship]], and [[xtools:blame|XTools Blame]] now support the French and Italian Wikipedias. More languages will be added in the near future. This is part of the [[m:Community Wishlist Survey 2023/Reading/Extend "Who Wrote That?" tool to more wikis|#7 wish in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T243711][https://phabricator.wikimedia.org/T270490][https://phabricator.wikimedia.org/T334891] * The [[:commons:Special:MyLanguage/Commons:Video2commons|Video2commons]] tool has been updated. This fixed several bugs related to YouTube uploads. [https://github.com/toolforge/video2commons/pull/162/commits] * The [[{{#special:Preferences}}]] page has been redesigned on mobile web. The new design makes it easier to browse the different categories and settings at low screen widths. You can also now access the page via a link in the Settings menu in the mobile web sidebar. [https://www.mediawiki.org/wiki/Moderator_Tools/Content_moderation_on_mobile_web/Preferences] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-05-02|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-05-03|en}}. It will be on all wikis from {{#time:j xg|2023-05-04|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/18|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W18"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:45, 2 May 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24966974 --> == Tech News: 2023-19 == <section begin="technews-2023-W19"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/19|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] Last week, Community Tech released the first update for providing [[m:Special:MyLanguage/Community Wishlist Survey 2022/Better diff handling of paragraph splits|better diffs]], the #1 request in the 2022 Community Wishlist Survey. [[phab:T324759|This update]] adds legends and tooltips to inline diffs so that users unfamiliar with the blue and yellow highlights can better understand the type of edits made. * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] When you close an image that is displayed via MediaViewer, it will now return to the wiki page instead of going back in your browser history. This feature request was [[m:Community Wishlist Survey 2023/Reading/Return to the article when closing the MediaViewer|voted #65 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T236591] * The [[mw:Special:MyLanguage/Extension:SyntaxHighlight|SyntaxHighlight]] extension now supports <bdi lang="en" dir="ltr"><code>wikitext</code></bdi> as a selected language. Old alternatives that were used to highlight wikitext, such as <bdi lang="en" dir="ltr"><code>html5</code></bdi>, <bdi lang="en" dir="ltr"><code>moin</code></bdi>, and <bdi lang="en" dir="ltr"><code>html+handlebars</code></bdi>, can now be replaced. [https://phabricator.wikimedia.org/T29828] * [[mw:Special:MyLanguage/Manual:Creating pages with preloaded text|Preloading text to new pages/sections]] now supports preloading from localized MediaWiki interface messages. [https://cs.wikipedia.org/wiki/User_talk:Martin_Urbanec_(WMF)?action=edit&section=new&preload=MediaWiki:July Here is an example] at the {{int:project-localized-name-cswiki/en}} that uses <bdi lang="zxx" dir="ltr"><code><nowiki>preload=MediaWiki:July</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T330337] '''Problems''' * Graph Extension update: Foundation developers have completed upgrading the visualization software to Vega5. Existing community graphs based on Vega2 are no longer compatible. Communities need to update local graphs and templates, and shared lua modules like <bdi lang="de" dir="ltr">[[:de:Modul:Graph]]</bdi>. The [https://vega.github.io/vega/docs/porting-guide/ Vega Porting guide] provides the most comprehensive detail on migration from Vega2 and [https://www.mediawiki.org/w/index.php?title=Template:Graph:PageViews&action=history here is an example migration]. Vega5 has currently just been enabled on mediawiki.org to provide a test environment for communities. [https://phabricator.wikimedia.org/T334940#8813922] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.8|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-05-09|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-05-10|en}}. It will be on all wikis from {{#time:j xg|2023-05-11|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Until now, all new OAuth apps went through manual review. Starting this week, apps using identification-only or basic authorizations will not require review. [https://phabricator.wikimedia.org/T67750] '''Future changes''' * During the next year, MediaWiki will stop using IP addresses to identify logged-out users, and will start automatically assigning unique temporary usernames. Read more at [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/Updates|IP Editing: Privacy Enhancement and Abuse Mitigation/Updates]]. You can [[m:Talk:IP Editing: Privacy Enhancement and Abuse Mitigation#What should it look like?|join the discussion]] about the [[m:Special:MyLanguage/IP Editing: Privacy Enhancement and Abuse Mitigation/Updates#What will temporary usernames look like?|format of the temporary usernames]]. [https://phabricator.wikimedia.org/T332805] * There will be an [[:w:en:A/B testing|A/B test]] on 10 Wikipedias where the Vector 2022 skin is the default skin. Half of logged-in desktop users will see an interface where the different parts of the page are more clearly separated. You can [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Updates/2023-05 Zebra9 A/B test|read more]]. [https://phabricator.wikimedia.org/T333180][https://phabricator.wikimedia.org/T335972] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] <code>jquery.tipsy</code> will be removed from the MediaWiki core. This will affect some user scripts. Many lines with <code>.tipsy(</code> can be commented out. <code>OO.ui.PopupWidget</code> can be used to keep things working like they are now. You can [[phab:T336019|read more]] and [[:mw:Help:Locating broken scripts|read about how to find broken scripts]]. [https://phabricator.wikimedia.org/T336019] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/19|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W19"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:36, 9 May 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=24998636 --> == Tech News: 2023-20 == <section begin="technews-2023-W20"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/20|Translations]] are available. '''Problems''' * Citations that are automatically generated based on [[d:Q33057|ISBN]] are currently broken. This affects citations made with the [[mw:Special:MyLanguage/Help:VisualEditor/User_guide/Citations-Full#Automatic|VisualEditor Automatic tab]], and the use of the citoid API in gadgets and user scripts. Work is ongoing to restore this feature. [https://phabricator.wikimedia.org/T336298] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.9|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-05-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-05-17|en}}. It will be on all wikis from {{#time:j xg|2023-05-18|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-gorwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hakwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hawwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hifwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hsbwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-htwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-iawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-iewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-igwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ilowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-inhwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-iowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-iswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-iuwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-jamwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-jvwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T308134] '''Future changes''' * There is a recently formed team at the Wikimedia Foundation which will be focusing on experimenting with new tools. Currently they are building [[m:Wikimedia_Foundation_Annual_Plan/2023-2024/Draft/Future_Audiences#FA2.2_Conversational_AI|a prototype ChatGPT plugin that allows information generated by ChatGPT to be properly attributed]] to the Wikimedia projects. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Gadget and userscript developers should replace <bdi lang="zxx" dir="ltr"><code>jquery.cookie</code></bdi> with <bdi lang="zxx" dir="ltr"><code>mediawiki.cookie</code></bdi>. The <bdi lang="zxx" dir="ltr"><code>jquery.cookie</code></bdi> library will be removed in ~1 month, and staff developers will run a script to replace any remaining uses at that time. [https://phabricator.wikimedia.org/T336018] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/20|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W20"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:45, 15 May 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25011501 --> == Tech News: 2023-21 == <section begin="technews-2023-W21"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/21|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The "recent edits" time period for page watchers is now 30 days. It used to be 180 days. This was a [[m:Community Wishlist Survey 2023/Notifications, Watchlists and Talk Pages/Change information about the number of watchers on a page|Community Wishlist Survey proposal]]. [https://phabricator.wikimedia.org/T336250] '''Changes later this week''' * An [[mw:special:MyLanguage/Growth/Positive reinforcement#Impact|improved impact module]] will be available at Wikipedias. The impact module is a feature available to newcomers [[mw:Special:MyLanguage/Growth/Feature summary#Newcomer homepage|at their personal homepage]]. It will show their number of edits, how many readers their edited pages have, how many thanks they have received and similar things. It is also accessible by accessing Special:Impact. [https://phabricator.wikimedia.org/T336203] * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.10|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-05-23|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-05-24|en}}. It will be on all wikis from {{#time:j xg|2023-05-25|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/21|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W21"/> 16:55, 22 May 2023 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25028325 --> == Tech News: 2023-22 == <section begin="technews-2023-W22"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/22|Translations]] are available. '''Recent changes''' * Citations can once again be added automatically from ISBNs, thanks to Zotero's ISBN searches. The current data sources are the Library of Congress (United States), the Bibliothèque nationale de France (French National Library), and K10plus ISBN (German repository). Additional data source searches can be [[mw:Citoid/Creating Zotero translators|proposed to Zotero]]. The ISBN labels in the [[mw:Special:MyLanguage/Help:VisualEditor/User_guide/Citations-Full#Automatic|VisualEditor Automatic tab]] will reappear later this week. [https://phabricator.wikimedia.org/T336298#8859917] * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The page [[{{#special:EditWatchlist}}]] now has "{{int:watchlistedit-normal-check-all}}" options to select all the pages within a namespace. This feature request was [[m:Community Wishlist Survey 2023/Notifications, Watchlists and Talk Pages/Watchlist edit - "check all" checkbox|voted #161 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T334252] '''Problems''' * For a few days earlier this month, the "Add interlanguage link" item in the Tools menu did not work properly. This has now been fixed. [https://phabricator.wikimedia.org/T337081] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.11|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-05-30|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-05-31|en}}. It will be on all wikis from {{#time:j xg|2023-06-01|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * VisualEditor will be switched to a new backend on [https://phabricator.wikimedia.org/source/mediawiki-config/browse/master/dblists/small.dblist small] and [https://phabricator.wikimedia.org/source/mediawiki-config/browse/master/dblists/medium.dblist medium] wikis this week. Large wikis will follow in the coming weeks. This is part of the effort to move Parsoid into MediaWiki core. The change should have no noticeable effect on users, but if you experience any slow loading or other strangeness when using VisualEditor, please report it on the phabricator ticket linked here. [https://phabricator.wikimedia.org/T320529] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/22|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W22"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:03, 29 May 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25079963 --> == Tech News: 2023-23 == <section begin="technews-2023-W23"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/23|Translations]] are available. '''Recent changes''' * The [[:mw:Special:MyLanguage/Help:Extension:RealMe|RealMe]] extension allows you to mark URLs on your user page as verified for Mastodon and similar software. * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] Citation and footnote editing can now be started from the reference list when using the visual editor. This feature request was [[m:Community Wishlist Survey 2023/Citations/Allow citations to be edited in the references section with VisualEditor|voted #2 in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T54750] * Previously, clicking on someone else's link to Recent Changes with filters applied within the URL could unintentionally change your preference for "{{int:Rcfilters-group-results-by-page}}". This has now been fixed. [https://phabricator.wikimedia.org/T202916#8874081] '''Problems''' * For a few days last week, some tools and bots returned outdated information due to database replication problems, and may have been down entirely while it was being fixed. These issues have now been fixed. [https://phabricator.wikimedia.org/T337446] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.12|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-06-06|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-06-07|en}}. It will be on all wikis from {{#time:j xg|2023-06-08|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Bots will no longer be prevented from making edits because of URLs that match the [[mw:Special:MyLanguage/Extension:SpamBlacklist|spam blacklist]]. [https://phabricator.wikimedia.org/T313107] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/23|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W23"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:52, 5 June 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25114640 --> == Tech News: 2023-24 == <section begin="technews-2023-W24"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/24|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] The content attribution tools [[mw:Special:MyLanguage/Who Wrote That?|Who Wrote That?]], [[xtools:authorship|XTools Authorship]], and [[xtools:blame|XTools Blame]] now support the Dutch, German, Hungarian, Indonesian, Japanese, Polish and Portuguese Wikipedias. This was the [[m:Community Wishlist Survey 2023/Reading/Extend "Who Wrote That?" tool to more wikis|#7 wish in the 2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T334891] * The [[mw:Special:MyLanguage/Structured Data Across Wikimedia/Search Improvements#Search Preview panel|Search Preview panel]] has been deployed on four Wikipedias (Catalan, Dutch, Hungarian and Norwegian). The panel will show an image related to the article (if existing), the top sections of the article, related images (coming from MediaSearch on Commons), and eventually the sister projects associated with the article. [https://phabricator.wikimedia.org/T306341] * The [[:mw:Special:MyLanguage/Help:Extension:RealMe#Verifying_a_link_on_non-user_pages|RealMe]] extension now allows administrators to verify URLs for any page, for Mastodon and similar software. [https://phabricator.wikimedia.org/T324937] * The default project license [https://lists.wikimedia.org/hyperkitty/list/wikimediaannounce-l@lists.wikimedia.org/thread/7G6XPWZPQFLZ2JANN3ZX6RT4DVUI3HZQ/ has been officially upgraded] to CC BY-SA 4.0. The software interface messages have been updated. Communities should feel free to start updating any mentions of the old CC BY-SA 3.0 licensing within policies and related documentation pages. [https://phabricator.wikimedia.org/T319064] '''Problems''' * For three days last month, some Wikipedia pages edited with VisualEditor or DiscussionTools had an unintended <code><nowiki>__TOC__</nowiki></code> (or its localized form) added during an edit. There is [[mw:Parsoid/Deployments/T336101_followup|a listing of affected pages sorted by wiki]], that may still need to be fixed. [https://phabricator.wikimedia.org/T336101] * Currently, the "{{int:Visualeditor-dialog-meta-categories-defaultsort-label}}" feature in VisualEditor is broken. Existing <code><nowiki>{{DEFAULTSORT:...}}</nowiki></code> keywords incorrectly appear as missing templates in VisualEditor. Developers are exploring how to fix this. In the meantime, those wishing to edit the default sortkey of a page are advised to switch to source editing. [https://phabricator.wikimedia.org/T337398] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Last week, an update to the delete form may have broken some gadgets or user scripts. If you need to manipulate (empty) the reason field, replace <bdi lang="zxx" dir="ltr"><code>#wpReason</code></bdi> with <bdi lang="zxx" dir="ltr" style="white-space: nowrap;"><code>#wpReason > input</code></bdi>. See [https://cs.wikipedia.org/w/index.php?title=MediaWiki%3AGadget-CleanDeleteReasons.js&diff=22859956&oldid=12794189 an example fix]. [https://phabricator.wikimedia.org/T337809] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.13|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-06-13|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-06-14|en}}. It will be on all wikis from {{#time:j xg|2023-06-15|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * VisualEditor will be switched to a new backend on English Wikipedia on Monday, and all other [https://phabricator.wikimedia.org/source/mediawiki-config/browse/master/dblists/large.dblist large] wikis on Thursday. The change should have no noticeable effect on users, but if you experience any slow loading or other strangeness when using VisualEditor, please report it on the phabricator ticket linked here. [https://phabricator.wikimedia.org/T320529] '''Future changes''' * From 5 June to 17 July, the Foundation's [[:mw:Wikimedia Security Team|Security team]] is holding a consultation with contributors regarding a draft policy to govern the use of third-party resources in volunteer-developed gadgets and scripts. Feedback and suggestions are warmly welcome at [[m:Special:MyLanguage/Third-party resources policy|Third-party resources policy]] on meta-wiki. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/24|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W24"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:51, 12 June 2023 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25133779 --> == Tech News: 2023-25 == <section begin="technews-2023-W25"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/25|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Flame graphs are now available in WikimediaDebug. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/JXNQD3EHG5V5QW5UXFDPSHQG4MJ3FWJQ/][https://techblog.wikimedia.org/2023/06/08/flame-graphs-arrive-in-wikimediadebug/] '''Changes later this week''' * There is no new MediaWiki version this week. * There is now a toolbar search popup in the visual editor. You can trigger it by typing <code>\</code> or pressing <code>ctrl + shift + p</code>. It can help you quickly access most tools in the editor. [https://commons.wikimedia.org/wiki/File:Visual_editor_toolbar_search_feature.png][https://phabricator.wikimedia.org/T66905] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/25|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W25"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:08, 19 June 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25159510 --> == Tech News: 2023-26 == <section begin="technews-2023-W26"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/26|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The Action API modules and Special:LinkSearch will now add a trailing <bdi lang="zxx" dir="ltr"><code>/</code></bdi> to all <bdi lang="zxx" dir="ltr"><code>prop=extlinks</code></bdi> responses for bare domains. This is part of the work to remove duplication in the <code>externallinks</code> database table. [https://phabricator.wikimedia.org/T337994] '''Problems''' * Last week, search was broken on Commons and Wikidata for 23 hours. [https://phabricator.wikimedia.org/T339810][https://wikitech.wikimedia.org/wiki/Incidents/2023-06-18_search_broken_on_wikidata_and_commons] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.15|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-06-27|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-06-28|en}}. It will be on all wikis from {{#time:j xg|2023-06-29|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The Minerva skin now applies more predefined styles to the <bdi lang="zxx" dir="ltr"><code>.mbox-text</code></bdi> CSS class. This enables support for mbox templates that use divs instead of tables. Please make sure that the new styles won't affect other templates in your wiki. [https://gerrit.wikimedia.org/r/c/mediawiki/skins/MinervaNeue/+/930901/][https://phabricator.wikimedia.org/T339040] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Gadgets will now load on both desktop and mobile by default. Previously, gadgets loaded only on desktop by default. Changing this default using the <bdi lang="zxx" dir="ltr"><code>|targets=</code></bdi> parameter is also deprecated and should not be used. You should make gadgets work on mobile or disable them based on the skin (with the <bdi lang="zxx" dir="ltr"><code>|skins=</code></bdi> parameter in <bdi lang="en" dir="ltr">MediaWiki:Gadgets-definition</bdi>) rather than whether the user uses the mobile or the desktop website. Popular gadgets that create errors on mobile will be disabled by developers on the Minerva skin as a temporary solution. [https://phabricator.wikimedia.org/T127268] * All namespace tabs now have the same browser [[m:Special:MyLanguage/Help:Keyboard_shortcuts|access key]] by default. Previously, custom and extension-defined namespaces would have to have their access keys set manually on-wiki, but that is no longer necessary. [https://phabricator.wikimedia.org/T22126] * The review form of the Flagged Revisions extension now uses the standardized [[mw:Special:MyLanguage/Codex|user interface components]]. [https://phabricator.wikimedia.org/T191156] '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] How media is structured in the parser's HTML output will change in the coming weeks at [[:wikitech:Deployments/Train#Thursday|group2 wikis]]. This change improves the accessibility of content. You may need to update your site-CSS, or userscripts and gadgets. There are [[mw:Special:MyLanguage/Parsoid/Parser_Unification/Media_structure/FAQ|details on what code to check, how to update the code, and where to report any related problems]]. [https://phabricator.wikimedia.org/T314318] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/26|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W26"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:18, 26 June 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25202311 --> == Tech News: 2023-27 == <section begin="technews-2023-W27"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/27|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] As part of the rolling out of the [[m:Community Wishlist Survey 2022/Multimedia and Commons/Audio links that play on click|audio links that play on click]] wishlist proposal, [https://noc.wikimedia.org/conf/highlight.php?file=dblists/small.dblist small wikis] will now be able to use the [[mw:Special:MyLanguage/Help:Extension:Phonos#Inline audio player mode|inline audio player]] that is implemented by the [[mw:Extension:Phonos|Phonos]] extension. [https://phabricator.wikimedia.org/T336763] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] From this week all gadgets automatically load on mobile and desktop sites. If you see any problems with gadgets on your wikis, please adjust the [[mw:Special:MyLanguage/Extension:Gadgets#Options|gadget options]] in your gadget definitions file. [https://phabricator.wikimedia.org/T328610] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.16|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-07-04|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-07-05|en}}. It will be on all wikis from {{#time:j xg|2023-07-06|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/27|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W27"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:51, 3 July 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25231546 --> == Tech News: 2023-28 == <section begin="technews-2023-W28"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/28|Translations]] are available. '''Recent changes''' * The [[:mw:Special:MyLanguage/Structured Data Across Wikimedia/Section-level Image Suggestions|Section-level Image Suggestions feature]] has been deployed on seven Wikipedias (Portuguese, Russian, Indonesian, Catalan, Hungarian, Finnish and Norwegian Bokmål). The feature recommends images for articles on contributors' watchlists that are a good match for individual sections of those articles. * [[:m:Special:MyLanguage/Global AbuseFilter|Global abuse filters]] have been enabled on all Wikimedia projects, except English and Japanese Wikipedias (who opted out). This change was made following a [[:m:Requests for comment/Make global abuse filters opt-out|global request for comments]]. [https://phabricator.wikimedia.org/T341159] * [[{{#special:BlockedExternalDomains}}]] is a new tool for administrators to help fight spam. It provides a clearer interface for blocking plain domains (and their subdomains), is more easily searchable, and is faster for the software to process for each edit on the wiki. It does not support regex (for complex cases), nor URL path-matching, nor the [[MediaWiki:Spam-whitelist|MediaWiki:Spam-whitelist]], but otherwise it replaces most of the functionalities of the existing [[MediaWiki:Spam-blacklist|MediaWiki:Spam-blacklist]]. There is a Python script to help migrate all simple domains into this tool, and more feature details, within [[mw:Special:MyLanguage/Manual:BlockedExternalDomains|the tool's documentation]]. It is available at all wikis except for Meta-wiki, Commons, and Wikidata. [https://phabricator.wikimedia.org/T337431] * The WikiEditor extension was updated. It includes some of the most frequently used features of wikitext editing. In the past, many of its messages could only be translated by administrators, but now all regular translators on translatewiki can translate them. Please check [https://translatewiki.net/wiki/Special:MessageGroupStats?group=ext-wikieditor&messages=&x=D#sortable:0=asc the state of WikiEditor localization into your language], and if the "Completion" for your language shows anything less than 100%, please complete the translation. See [https://lists.wikimedia.org/hyperkitty/list/wikitech-ambassadors@lists.wikimedia.org/thread/D4YELU2DXMZ75PGELUOKXXMFF3FH45XA/ a more detailed explanation]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.17|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-07-11|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-07-12|en}}. It will be on all wikis from {{#time:j xg|2023-07-13|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * The default protocol of [[{{#special:LinkSearch}}]] and API counterparts has changed from http to both http and https. [https://phabricator.wikimedia.org/T14810] * [[{{#special:LinkSearch}}]] and its API counterparts will now search for all of the URL provided in the query. It used to be only the first 60 characters. This feature was requested fifteen years ago. [https://phabricator.wikimedia.org/T17218] '''Future changes''' * There is an experiment with a [[:w:en:ChatGPT|ChatGPT]] plugin. This is to show users where the information is coming from when they read information from Wikipedia. It has been tested by Wikimedia Foundation staff and other Wikimedians. Soon all ChatGPT plugin users can use the Wikipedia plugin. This is the same plugin which was mentioned in [[m:Special:MyLanguage/Tech/News/2023/20|Tech News 2023/20]]. [https://meta.wikimedia.org/wiki/Wikimedia_Foundation_Annual_Plan/2023-2024/Draft/Future_Audiences#FA2.2_Conversational_AI] * There is an ongoing discussion on a [[m:Special:MyLanguage/Third-party resources policy|proposed Third-party resources policy]]. The proposal will impact the use of third-party resources in gadgets and userscripts. Based on the ideas received so far, policy includes some of the risks related to user scripts and gadgets loading third-party resources, some best practices and exemption requirements such as code transparency and inspectability. Your feedback and suggestions are warmly welcome until July 17, 2023 on [[m:Talk:Third-party resources policy|on the policy talk page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/28|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W28"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:54, 10 July 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25278797 --> == Tech News: 2023-29 == <section begin="technews-2023-W29"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/29|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] We are now serving 1% of all global user traffic from [[w:en:Kubernetes|Kubernetes]] (you can [[wikitech:MediaWiki On Kubernetes|read more technical details]]). We are planning to increment this percentage regularly. You can [[phab:T290536|follow the progress of this work]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.18|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-07-18|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-07-19|en}}. It will be on all wikis from {{#time:j xg|2023-07-20|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] MediaWiki [[mw:Special:MyLanguage/Help:System_message|system messages]] will now look for available local fallbacks, instead of always using the default fallback defined by software. This means wikis no longer need to override each language on the [[mw:Special:MyLanguage/Manual:Language#Fallback_languages|fallback chain]] separately. For example, English Wikipedia doesn't have to create <bdi lang="zxx" dir="ltr"><code>en-ca</code></bdi> and <bdi lang="zxx" dir="ltr"><code>en-gb</code></bdi> subpages with a transclusion of the base pages anymore. This makes it easier to maintain local overrides. [https://phabricator.wikimedia.org/T229992] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The <bdi lang="zxx" dir="ltr"><code>action=growthsetmentorstatus</code></bdi> API will be deprecated with the new MediaWiki version. Bots or scripts calling that API should use the <bdi lang="zxx" dir="ltr"><code>action=growthmanagementorlist</code></bdi> API now. [https://phabricator.wikimedia.org/T321503] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/29|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W29"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:08, 17 July 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25289122 --> == Tech News: 2023-30 == <section begin="technews-2023-W30"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/30|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] On July 18, the Wikimedia Foundation launched a survey about the [[:mw:Technical_decision_making|technical decision making process]] for people who do technical work that relies on software that is maintained by the Foundation or affiliates. If this applies to you, [https://wikimediafoundation.limesurvey.net/885471 please take part in the survey]. The survey will be open for three weeks, until August 7. You can find more information in [[listarchive:list/wikitech-l@lists.wikimedia.org/thread/Q7DUCFA75DXG3G2KHTO7CEWMLCYTSDB2/|the announcement e-mail on wikitech-l]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.19|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-07-25|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-07-26|en}}. It will be on all wikis from {{#time:j xg|2023-07-27|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/30|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W30"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 02:20, 25 July 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25332248 --> == Tech News: 2023-31 == <section begin="technews-2023-W31"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/31|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The [[mw:Synchronizer|Synchronizer]] tool is now available to keep Lua modules synced across Wikimedia wikis, along with [[mw:Multilingual Templates and Modules|updated documentation]] to develop global Lua modules and templates. * The tag filter on [[{{#special:NewPages}}]] and revision history pages can now be inverted. For example, you can hide edits that were made using an automated tool. [https://phabricator.wikimedia.org/T334337][https://phabricator.wikimedia.org/T334338] * The Wikipedia [[:w:en:ChatGPT|ChatGPT]] plugin experiment can now be used by ChatGPT users who can use plugins. You can participate in a [[:m:Talk:Wikimedia Foundation Annual Plan/2023-2024/Draft/Future Audiences#Announcing monthly Future Audiences open "office hours"|video call]] if you want to talk about this experiment or similar work. [https://meta.wikimedia.org/wiki/Wikimedia_Foundation_Annual_Plan/2023-2024/Draft/Future_Audiences#FA2.2_Conversational_AI] '''Problems''' * It was not possible to generate a PDF for pages with non-Latin characters in the title, for the last two weeks. This has now been fixed. [https://phabricator.wikimedia.org/T342442] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.20|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-08-01|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-08-02|en}}. It will be on all wikis from {{#time:j xg|2023-08-03|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Starting on Tuesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-kawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kaawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kabwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kbdwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kbpwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kkwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kmwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-knwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kshwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kuwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kwwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T308135] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W31"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:54, 31 July 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25362228 --> == Tech News: 2023-32 == <section begin="technews-2023-W32"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/32|Translations]] are available. '''Recent changes''' * Mobile Web editors can now [[mw:Special:MyLanguage/Reading/Web/Advanced_mobile_contributions#August_1,_2023_-_Full-page_editing_added_on_mobile|edit a whole page at once]]. To use this feature, turn on "{{int:Mobile-frontend-mobile-option-amc}}" in your settings and use the "{{int:Minerva-page-actions-editfull}}" button in the "{{int:Minerva-page-actions-overflow}}" menu. [https://phabricator.wikimedia.org/T203151] '''Changes later this week''' * There is no new MediaWiki version this week. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W32"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:20, 7 August 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25420038 --> == Tech News: 2023-33 == <section begin="technews-2023-W33"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/33|Translations]] are available. '''Recent changes''' * The Content translation system is no longer using Youdao's [[mw:Special:MyLanguage/Help:Content_translation/Translating/Initial_machine_translation|machine translation service]]. The service was in place for several years, but due to no usage, and availability of alternatives, it was deprecated to reduce maintenance overheads. Other services which cover the same languages are still available. [https://phabricator.wikimedia.org/T329137] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.22|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-08-15|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-08-16|en}}. It will be on all wikis from {{#time:j xg|2023-08-17|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-lawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ladwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lbwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lbewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lezwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lfnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-liwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lijwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lmowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ltgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lvwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-maiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-map_bmswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mdfwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kywiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T308136] <!-- TODO replace wiki codes --> '''Future changes''' * A few gadgets/user scripts which add icons to the Minerva skin need to have their CSS updated. There are more details available including a [[phab:T344067|search for all existing instances and how to update them]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W33"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 05:59, 15 August 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25428668 --> == Tech News: 2023-34 == <section begin="technews-2023-W34"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/34|Translations]] are available. '''Recent changes''' * The [https://gdrive-to-commons.toolforge.org/ GDrive to Commons Uploader] tool is now available. It enables [[m:Special:MyLanguage/GDrive to Commons Uploader|securely selecting and uploading files]] from your Google Drive directly to Wikimedia Commons. [https://phabricator.wikimedia.org/T267868] * From now on, we will announce new Wikimedia wikis in Tech News, so you can update any tools or pages. ** Since the last edition, two new wikis have been created: *** a Wiktionary in [[d:Q7121294|Pa'O]] ([[wikt:blk:|<code>wikt:blk:</code>]]) [https://phabricator.wikimedia.org/T343540] *** a Wikisource in [[d:Q34002|Sundanese]] ([[s:su:|<code>s:su:</code>]]) [https://phabricator.wikimedia.org/T343539] ** To catch up, the next most recent six wikis are: *** Wikifunctions ([[f:|<code>f:</code>]]) [https://phabricator.wikimedia.org/T275945] *** a Wiktionary in [[d:Q2891049|Mandailing]] ([[wikt:btm:|<code>wikt:btm:</code>]]) [https://phabricator.wikimedia.org/T335216] *** a Wikipedia in [[d:Q5555465|Ghanaian Pidgin]] ([[w:gpe:|<code>w:gpe:</code>]]) [https://phabricator.wikimedia.org/T335969] *** a Wikinews in [[d:Q3111668|Gungbe]] ([[n:guw:|<code>n:guw:</code>]]) [https://phabricator.wikimedia.org/T334394] *** a Wiktionary in [[d:Q33522|Kabardian]] ([[wikt:kbd:|<code>wikt:kbd:</code>]]) [https://phabricator.wikimedia.org/T333266] *** a Wikipedia in [[d:Q35570|Fante]] ([[w:fat:|<code>w:fat:</code>]]) [https://phabricator.wikimedia.org/T335016] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-08-22|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-08-23|en}}. It will be on all wikis from {{#time:j xg|2023-08-24|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] There is an existing [[mw:Stable interface policy|stable interface policy]] for MediaWiki backend code. There is a [[mw:User:Jdlrobson/Stable interface policy/frontend|proposed stable interface policy for frontend code]]. This is relevant for anyone who works on gadgets or Wikimedia frontend code. You can read it, discuss it, and let the proposer know if there are any problems. [https://phabricator.wikimedia.org/T344079] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W34"/> 15:25, 21 August 2023 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25497111 --> == Tech News: 2023-35 == <section begin="technews-2023-W35"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/35|Translations]] are available. '''Recent changes''' * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] As part of the changes for the [[m:Community Wishlist Survey 2022/Better diff handling of paragraph splits|better diff handling of paragraph splits]], improved detection of splits is being rolled out. Over the last two weeks, we deployed this support to [[wikitech:Deployments/Train#Groups|group0]] and group1 wikis. This week it will be deployed to group2 wikis. [https://phabricator.wikimedia.org/T341754] * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] All [[{{#special:Contributions}}]] pages now show the user's local edit count and the account's creation date. [https://phabricator.wikimedia.org/T324166] * Wikisource users can now use the <bdi lang="zxx" dir="ltr"><code>prpbengalicurrency</code></bdi> label to denote Bengali currency characters as page numbers inside the <bdi lang="zxx" dir="ltr"><code><nowiki><pagelist></nowiki></code></bdi> tag. [https://phabricator.wikimedia.org/T268932] * Two preferences have been relocated. The preference "{{int:visualeditor-preference-visualeditor}}" is now shown on the [[Special:Preferences#mw-prefsection-editing|"{{int:prefs-editing}}" tab]] at all wikis. Previously it was shown on the "{{int:prefs-betafeatures}}" tab at some wikis. The preference "{{int:visualeditor-preference-newwikitexteditor-enable}}" is now also shown on the "{{int:prefs-editing}}" tab at all wikis, instead of the "{{int:prefs-betafeatures}}" tab. [https://phabricator.wikimedia.org/T335056][https://phabricator.wikimedia.org/T344158] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.24|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-08-29|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-08-30|en}}. It will be on all wikis from {{#time:j xg|2023-08-31|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] New signups for a Wikimedia developer account will start being pushed towards <bdi lang="en" dir="ltr">[https://idm.wikimedia.org/ idm.wikimedia.org]</bdi>, rather than going via Wikitech. [[wikitech:IDM|Further information about the new system is available]]. * All right-to-left language wikis, plus Korean, Armenian, Ukrainian, Russian, and Bulgarian Wikipedias, will have a link in the sidebar that provides a short URL of that page, using the [[m:Special:MyLanguage/Wikimedia URL Shortener|Wikimedia URL Shortener]]. This feature will come to more wikis in future weeks. [https://phabricator.wikimedia.org/T267921] '''Future changes''' * The removal of the [[mw:Special:MyLanguage/Extension:DoubleWiki|DoubleWiki extension]] is being discussed. This extension currently allows Wikisource users to view articles from multiple language versions side by side when the <bdi lang="zxx" dir="ltr"><code><=></code></bdi> symbol next to a specific language edition is selected. Comments on this are welcomed at [[phab:T344544|the phabricator task]]. * A proposal has been made to merge the second hidden-categories list (which appears below the wikitext editing form) with the main list of categories (which is further down the page). [[phab:T340606|More information is available on Phabricator]]; feedback is welcome! '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W35"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:00, 28 August 2023 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25510866 --> == Tech News: 2023-36 == <section begin="technews-2023-W36"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/36|Translations]] are available. '''Recent changes''' * [[m:Wikisource_EditInSequence|EditInSequence]], a feature that allows users to edit pages faster on Wikisource has been moved to a Beta Feature based on community feedback. To enable it, you can navigate to the [[Special:Preferences#mw-prefsection-betafeatures|beta features tab in Preferences]]. [https://phabricator.wikimedia.org/T308098] * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] As part of the changes for the [[m:Special:MyLanguage/Community Wishlist Survey 2022/Generate Audio for IPA|Generate Audio for IPA]] and [[m:Community Wishlist Survey 2022/Multimedia and Commons/Audio links that play on click|Audio links that play on click]] wishlist proposals, the [[mw:Special:MyLanguage/Help:Extension:Phonos#Inline_audio_player_mode|inline audio player mode]] of [[mw:Extension:Phonos|Phonos]] has been deployed to all projects. [https://phabricator.wikimedia.org/T336763] * There is a new option for Administrators when they are changing the usergroups for a user, to add the user’s user page to their watchlist. This works both via [[{{#special:UserRights}}]] and via the API. [https://phabricator.wikimedia.org/T272294] * One new wiki has been created: ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q34318|Talysh]] ([[w:tly:|<code>w:tly:</code>]]) [https://phabricator.wikimedia.org/T345166] '''Problems''' * The [[mw:Special:MyLanguage/Extension:LoginNotify|LoginNotify extension]] was not sending notifications since January. It has now been fixed, so going forward, you may see notifications for failed login attempts, and successful login attempts from a new device. [https://phabricator.wikimedia.org/T344785] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.25|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-09-05|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-09-06|en}}. It will be on all wikis from {{#time:j xg|2023-09-07|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-mhrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-miwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-minwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mkwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mrjwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mtwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mwlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-myvwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mznwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nahwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-napwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ndswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nds_nlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-newiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-newwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-novwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nqowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nrmwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nsowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nvwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ocwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-olowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-omwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-orwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-oswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pagwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pamwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-papwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pcdwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pdcwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pflwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pihwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pmswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pnbwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pntwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pswiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T308137][https://phabricator.wikimedia.org/T308138] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W36"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:33, 4 September 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25566983 --> == Tech News: 2023-37 == <section begin="technews-2023-W37"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/37|Translations]] are available. '''Recent changes''' * [[mw:Special:MyLanguage/ORES|ORES]], the revision evaluation service, is now using a new open-source infrastructure on all wikis except for English Wikipedia and Wikidata. These two will follow this week. If you notice any unusual results from the Recent Changes filters that are related to ORES (for example, "{{int:ores-rcfilters-damaging-title}}" and "{{int:ores-rcfilters-goodfaith-title}}"), please [[mw:Talk:Machine Learning|report them]]. [https://phabricator.wikimedia.org/T342115] * When you are logged in on one Wikimedia wiki and visit a different Wikimedia wiki, the system tries to log you in there automatically. This has been unreliable for a long time. You can now visit the login page to make the system try extra hard. If you feel that made logging in better or worse than it used to be, your feedback is appreciated. [https://phabricator.wikimedia.org/T326281] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.26|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-09-12|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-09-13|en}}. It will be on all wikis from {{#time:j xg|2023-09-14|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The [[mw:Special:MyLanguage/Technical decision making|Technical Decision-Making Forum Retrospective]] team invites anyone involved in the technical field of Wikimedia projects to signup to and join [[mw:Technical decision making/Listening Sessions|one of their listening sessions]] on 13 September. Another date will be scheduled later. The goal is to improve the technical decision-making processes. * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] As part of the changes for the [[m:Special:MyLanguage/Community Wishlist Survey 2022/Better diff handling of paragraph splits|Better diff handling of paragraph splits]] wishlist proposal, the inline switch widget in diff pages is being rolled out this week to all wikis. The inline switch will allow viewers to toggle between a unified inline or two-column diff wikitext format. [https://phabricator.wikimedia.org/T336716] '''Future changes''' * All wikis will be read-only for a few minutes on 20 September. [[m:Special:MyLanguage/Tech/Server switch|This is planned at 14:00 UTC.]] More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T345263] * The Enterprise API is launching a new feature called "[http://breakingnews-beta.enterprise.wikimedia.com/ breaking news]". Currently in BETA, this attempts to identify likely "newsworthy" topics as they are currently being written about in any Wikipedia. Your help is requested to improve the accuracy of its detection model, especially on smaller language editions, by recommending templates or identifiable editing patterns. See more information at [[mw:Special:MyLanguage/Wikimedia Enterprise/Breaking news|the documentation page]] on MediaWiki or [[m:Special:MyLanguage/Wikimedia Enterprise/FAQ#What is Breaking News|the FAQ]] on Meta. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W37"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:07, 11 September 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25589064 --> == Tech News: 2023-38 == <section begin="technews-2023-W38"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/38|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] MediaWiki now has a [[mw:Stable interface policy/frontend|stable interface policy for frontend code]] that more clearly defines how we deprecate MediaWiki code and wiki-based code (e.g. gadgets and user scripts). Thank you to everyone who contributed to the content and discussions. [https://phabricator.wikimedia.org/T346467][https://phabricator.wikimedia.org/T344079] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.27|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-09-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-09-20|en}}. It will be on all wikis from {{#time:j xg|2023-09-21|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * All wikis will be read-only for a few minutes on September 20. [[m:Special:MyLanguage/Tech/Server switch|This is planned at 14:00 UTC.]] [https://phabricator.wikimedia.org/T345263] * All wikis will have a link in the sidebar that provides a short URL of that page, using the [[m:Special:MyLanguage/Wikimedia URL Shortener|Wikimedia URL Shortener]]. [https://phabricator.wikimedia.org/T267921] '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The team investigating the Graph Extension posted [[mw:Extension:Graph/Plans#Proposal|a proposal for reenabling it]] and they need your input. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W38"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:19, 18 September 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25623533 --> == Tech News: 2023-39 == <section begin="technews-2023-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/39|Translations]] are available. '''Recent changes''' * The Vector 2022 skin will now remember the pinned/unpinned status for the Table of Contents for all logged-out users. [https://phabricator.wikimedia.org/T316060] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.28|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-09-26|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-09-27|en}}. It will be on all wikis from {{#time:j xg|2023-09-28|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The ResourceLoader <bdi lang="zxx" dir="ltr"><code><nowiki>mediawiki.ui</nowiki></code></bdi> modules are now deprecated as part of the move to Vue.js and Codex. There is a [[mw:Codex/Migrating_from_MediaWiki_UI|guide for migrating from MediaWiki UI to Codex]] for any tools that use it. More [[phab:T346468|details are available in the task]] and your questions are welcome there. * Gadget definitions will have a [[mw:Special:MyLanguage/Extension:Gadgets#Options|new "namespaces" option]]. The option takes a list of namespace IDs. Gadgets that use this option will only load on pages in the given namespaces. '''Future changes''' * New variables will be added to [[mw:Special:MyLanguage/Extension:AbuseFilter|AbuseFilter]]: <code><bdi lang="zxx" dir="ltr">global_account_groups</bdi></code> and <code><bdi lang="zxx" dir="ltr">global_account_editcount</bdi></code>. They are available only when an account is being created. You can use them to prevent blocking automatic creation of accounts when users with many edits elsewhere visit your wiki for the first time. [https://phabricator.wikimedia.org/T345632][https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:AbuseFilter/Rules_format] '''Meetings''' * You can join the next meeting with the Wikipedia mobile apps teams. During the meeting, we will discuss the current features and future roadmap. The meeting will be on [https://zonestamp.toolforge.org/1698426015 27 October at 17:00 (UTC)]. See [[mw:Special:MyLanguage/Wikimedia_Apps/Office_Hours#October_2023|details and how to join]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W39"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:51, 26 September 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25655264 --> == Tech News: 2023-40 == <section begin="technews-2023-W40"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/40|Translations]] are available. '''Recent changes''' * There is a new [[Special:Preferences#mw-prefsection-rendering-advancedrendering|user preference]] for "{{int:tog-forcesafemode}}". This setting will make pages load without including any on-wiki JavaScript or on-wiki stylesheet pages. It can be useful for debugging broken JavaScript gadgets. [https://phabricator.wikimedia.org/T342347] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Gadget definitions now have a [[mw:Special:MyLanguage/Extension:Gadgets#Options|new "<var>contentModels</var>" option]]. The option takes a list of page content models, like <code><bdi lang="zxx" dir="ltr">wikitext</bdi></code> or <code><bdi lang="zxx" dir="ltr">css</bdi></code>. Gadgets that use this option will only load on pages with the given content models. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.29|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-10-03|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-10-04|en}}. It will be on all wikis from {{#time:j xg|2023-10-05|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The Vector 2022 skin will no longer use the custom styles and scripts of Vector legacy (2010). The change will be made later this year or in early 2024. See [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Features/Loading Vector 2010 scripts|how to adjust the CSS and JS pages on your wiki]]. [https://phabricator.wikimedia.org/T331679] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W40"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:26, 3 October 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25686930 --> == Tech News: 2023-41 == <section begin="technews-2023-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/41|Translations]] are available. '''Recent changes''' * One new wiki has been created: a {{int:project-localized-name-group-wikipedia}} in [[d:Q33291|Fon]] ([[w:fon:|<code>w:fon:</code>]]) [https://phabricator.wikimedia.org/T347935] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.41/wmf.30|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-10-10|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-10-11|en}}. It will be on all wikis from {{#time:j xg|2023-10-12|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-swwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-wawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-warwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-wowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-xalwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-xhwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-xmfwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-yiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-yowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-zawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-zeawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-zh_min_nanwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-zuwiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T308139] * At some wikis, newcomers are suggested images from Commons to add to articles without any images. Starting on Tuesday, newcomers at these wikis will be able to add images to unillustrated article sections. The specific wikis are listed under "Images recommendations" [[mw:Special:MyLanguage/Growth/Deployment table|at the Growth team deployment table]]. You can [[mw:Special:MyLanguage/Help:Growth/Tools/Add an image|learn more about this feature.]] [https://phabricator.wikimedia.org/T345940] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] In the mobile web skin (Minerva) the CSS ID <bdi lang="zxx" dir="ltr"><code><nowiki>#page-actions</nowiki></code></bdi> will be replaced with <bdi lang="zxx" dir="ltr"><code><nowiki>#p-views</nowiki></code></bdi>. This change is to make it consistent with other skins and to improve support for gadgets and extensions in the mobile skin. A few gadgets may need to be updated; there are [https://phabricator.wikimedia.org/T348267 details and search-links in the task]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W41"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:39, 9 October 2023 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25712895 --> == Tech News: 2023-42 == <section begin="technews-2023-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/42|Translations]] are available. '''Recent changes''' * The [[m:Special:MyLanguage/Help:Unified login|Unified login]] system's edge login should now be fixed for some browsers (Chrome, Edge, Opera). This means that if you visit a new sister project wiki, you should be logged in automatically without the need to click "Log in" or reload the page. Feedback on whether it's working for you is welcome. [https://phabricator.wikimedia.org/T347889] * [[mw:Special:MyLanguage/Manual:Interface/Edit_notice|Edit notices]] are now available within the MobileFrontend/Minerva skin. This feature was inspired by [[w:en:Wikipedia:EditNoticesOnMobile|the gadget on English Wikipedia]]. See more details in [[phab:T316178|T316178]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.1|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-10-17|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-10-18|en}}. It will be on all wikis from {{#time:j xg|2023-10-19|en}} ([[mw:MediaWiki 1.41/Roadmap|calendar]]). '''Future changes''' * In 3 weeks, in the Vector 2022 skin, code related to <bdi lang="zxx" dir="ltr"><code><nowiki>addPortletLink</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>#p-namespaces</nowiki></code></bdi> that was deprecated one year ago will be removed. If you notice tools that should appear next to the "Discussion" tab are then missing, please tell the gadget's maintainers to see [[phab:T347907|instructions in the Phabricator task]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W42"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:47, 16 October 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25745824 --> == Tech News: 2023-43 == <section begin="technews-2023-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/43|Translations]] are available. '''Recent changes''' * There is a new [[mw:Special:MyLanguage/Wikimedia Language engineering/Newsletter/2023/October|Language and internationalization newsletter]], written quarterly. It contains updates on new feature development, improvements in various language-related technical projects, and related support work. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Source map support has been enabled on all wikis. When you open the debugger in your browser's developer tools, you should be able to see the unminified JavaScript source code. [https://phabricator.wikimedia.org/T47514] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.2|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-10-24|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-10-25|en}}. It will be on all wikis from {{#time:j xg|2023-10-26|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W43"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:16, 23 October 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25782286 --> == Tech News: 2023-44 == <section begin="technews-2023-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/44|Translations]] are available. '''Recent changes''' * The Structured Content team, as part of its project of [[:commons:Commons:WMF support for Commons/Upload Wizard Improvements|improving UploadWizard on Commons]], made some UX improvements to the upload step of choosing own vs not own work ([[phab:T347590|T347590]]), as well as to the licensing step for own work ([[phab:T347756|T347756]]). * The Design Systems team has released version 1.0.0 of [[wmdoc:codex/latest/|Codex]], the new design system for Wikimedia. See the [[mw:Special:MyLanguage/Design_Systems_Team/Announcing_Codex_1.0|full announcement about the release of Codex 1.0.0]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.3|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-10-31|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-11-01|en}}. It will be on all wikis from {{#time:j xg|2023-11-02|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). * Listings on category pages are sorted on each wiki for that language using a [[:w:en:International Components for Unicode|library]]. For a brief period on 2 November, changes to categories will not be sorted correctly for many languages. This is because the developers are upgrading to a new version of the library. They will then use a script to fix the existing categories. This will take a few hours or a few days depending on how big the wiki is. You can [[mw:Special:MyLanguage/Wikimedia Technical Operations/ICU announcement|read more]]. [https://phabricator.wikimedia.org/T345561][https://phabricator.wikimedia.org/T267145] * Starting November 1, the impact module (Special:Impact) will be upgraded by the Growth team. The new impact module shows newcomers more data regarding their impact on the wiki. It was tested by a few wikis during the last few months. [https://phabricator.wikimedia.org/T336203] '''Future changes''' * There is [[mw:Special:MyLanguage/Extension:Graph/Plans#Roadmap|a proposed plan]] for re-enabling the Graph Extension. You can help by reviewing this proposal and [[mw:Extension_talk:Graph/Plans#c-PPelberg_(WMF)-20231020221600-Update:_20_October|sharing what you think about it]]. * The WMF is working on making it possible for administrators to [[mw:Special:MyLanguage/Community_configuration_2.0|edit MediaWiki configuration directly]]. This is similar to previous work on Special:EditGrowthConfig. [[phab:T349757|A technical RfC is running until November 08, where you can provide feedback.]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W44"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:21, 30 October 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25801989 --> == Tech News: 2023-45 == <section begin="technews-2023-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/45|Translations]] are available. '''Recent changes''' * In the Vector 2022 skin, the default font-size of a number of navigational elements (tagline, tools menu, navigational links, and more) has been increased slightly to match the font size used in page content. [https://phabricator.wikimedia.org/T346062] '''Problems''' * Last week, there was a problem displaying some recent edits on [https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist a few wikis], for 1-6 hours. The edits were saved but not immediately shown. This was due to a database problem. [https://phabricator.wikimedia.org/T350443] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.4|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-11-07|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-11-08|en}}. It will be on all wikis from {{#time:j xg|2023-11-09|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). * The Growth team will reassign newcomers from former mentors to [[mw:Special:MyLanguage/Growth/Structured mentor list|the currently active mentors]]. They have also changed the notification language to be more user-friendly. [https://phabricator.wikimedia.org/T330071][https://phabricator.wikimedia.org/T327493] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W45"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:05, 6 November 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25838105 --> == Tech News: 2023-46 == <section begin="technews-2023-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/46|Translations]] are available. '''Recent changes''' * Four new wikis have been created: ** a Wikipedia in [[d:Q7598268|Moroccan Amazigh]] ([[w:zgh:|<code>w:zgh:</code>]]) [https://phabricator.wikimedia.org/T350216] ** a Wikipedia in [[d:Q35159|Dagaare]] ([[w:dga:|<code>w:dga:</code>]]) [https://phabricator.wikimedia.org/T350218] ** a Wikipedia in [[d:Q33017|Toba Batak]] ([[w:bbc:|<code>w:bbc:</code>]]) [https://phabricator.wikimedia.org/T350320] ** a Wikiquote in [[d:Q33151|Banjar]] ([[q:bjn:|<code>q:bjn:</code>]]) [https://phabricator.wikimedia.org/T350217] '''Problems''' * Last week, users who previously visited Meta-Wiki or Wikimedia Commons and then became logged out on those wikis could not log in again. The problem is now resolved. [https://phabricator.wikimedia.org/T350695] * Last week, some pop-up dialogs and menus were shown with the wrong font size. The problem is now resolved. [https://phabricator.wikimedia.org/T350544] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-11-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-11-15|en}}. It will be on all wikis from {{#time:j xg|2023-11-16|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). '''Future changes''' * Reference Previews are coming to many wikis as a default feature. They are popups for references, similar to the [[mw:Special:MyLanguage/Page Previews|PagePreviews feature]]. [[m:WMDE Technical Wishes/ReferencePreviews#Opt-out feature|You can opt out]] of seeing them. If you are [[Special:Preferences#mw-prefsection-gadgets|using the gadgets]] Reference Tooltips or Navigation Popups, you won’t see Reference Previews. [[phab:T282999|Deployment]] is planned for November 22, 2023. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Canary (also known as heartbeat) events will be produced into [https://stream.wikimedia.org/?doc#/streams Wikimedia event streams] from December 11. Streams users are advised to filter out these events, by discarding all events where <bdi lang="zxx" dir="ltr"><code><nowiki>meta.domain == "canary"</nowiki></code></bdi>. Updates to [[mw:Special:MyLanguage/Manual:Pywikibot|Pywikibot]] or [https://github.com/ChlodAlejandro/wikimedia-streams wikimedia-streams] will discard these events by default. [https://phabricator.wikimedia.org/T266798] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W46"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:52, 13 November 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25859263 --> == Tech News: 2023-47 == <section begin="technews-2023-W47"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/47|Translations]] are available. '''Changes later this week''' * There is no new MediaWiki version this week. [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * Starting on Wednesday, a new set of Wikipedias will get "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]" ({{int:project-localized-name-quwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-rmwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-rmywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-rnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-roa_rupwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-roa_tarawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ruewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-rwwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sahwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-satwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-scwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-scnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-scowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sdwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-shwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-siwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-skwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-slwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-smwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sqwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-srwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-srnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-sswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-stwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-stqwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-suwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-szlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tcywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tetwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tgwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-thwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tkwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-towiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tpiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-trwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ttwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-twwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tyvwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-udmwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ugwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-uzwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-vewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-vecwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-vepwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-vlswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-vowiki/en}}). This is part of the [[phab:T304110|progressive deployment of this tool to more Wikipedias]]. The communities can [[mw:Special:MyLanguage/Growth/Community configuration|configure how this feature works locally]]. [https://phabricator.wikimedia.org/T308141][https://phabricator.wikimedia.org/T308142][https://phabricator.wikimedia.org/T308143] * The Vector 2022 skin will have some minor visual changes to drop-down menus, column widths, and more. These changes were added to four Wikipedias last week. If no issues are found, these changes will proceed to all wikis this week. These changes will make it possible to add new menus for readability and dark mode. [[mw:Special:MyLanguage/Reading/Web/Desktop_Improvements/Updates#November_2023:_Visual_changes,_more_deployments,_and_shifting_focus|Learn more]]. [https://phabricator.wikimedia.org/T347711] '''Future changes''' * There is [[mw:Extension talk:Graph/Plans#Update: 15 November|an update on re-enabling the Graph Extension]]. To speed up the process, Vega 2 will not be supported and only [https://phabricator.wikimedia.org/T335325 some protocols] will be available at launch. You can help by sharing what you think about the plan. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/47|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W47"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:55, 21 November 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25884616 --> == Tech News: 2023-48 == <section begin="technews-2023-W48"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/48|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-11-28|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-11-29|en}}. It will be on all wikis from {{#time:j xg|2023-11-30|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). There is no new MediaWiki version next week. [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] MediaWiki's JavaScript system will now allow <bdi lang="zxx" dir="ltr"><code>async</code>/<code>await</code></bdi> syntax in gadgets and user scripts. Gadget authors should remember that users' browsers may not support it, so it should be used appropriately. [https://phabricator.wikimedia.org/T343499] * The deployment of "[[mw:Special:MyLanguage/Help:Growth/Tools/Add_a_link|Add a link]]" announced [[m:Special:MyLanguage/Tech/News/2023/47|last week]] was postponed. It will resume this week. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/48|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W48"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:08, 27 November 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25906379 --> == Tech News: 2023-49 == <section begin="technews-2023-W49"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/49|Translations]] are available. '''Recent changes''' * The spacing between paragraphs on Vector 2022 has been changed from 7px to 14px to match the size of the text. This will make it easier to distinguish paragraphs from sentences. [https://phabricator.wikimedia.org/T351754] * The "{{int:Visualeditor-dialog-meta-categories-defaultsort-label}}" feature in VisualEditor is working again. You no longer need to switch to source editing to edit <bdi lang="zxx" dir="ltr"><code><nowiki>{{DEFAULTSORT:...}}</nowiki></code></bdi> keywords. [https://phabricator.wikimedia.org/T337398] '''Changes later this week''' * There is no new MediaWiki version this week. [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * On 6 December, people who have the enabled the preference for "{{int:Discussiontools-preference-visualenhancements}}" will notice the [[mw:Special:MyLanguage/Talk pages project/Usability|talk page usability improvements]] appear on pages that include the <bdi lang="zxx" dir="ltr"><code><nowiki>__NEWSECTIONLINK__</nowiki></code></bdi> magic word. If you notice any issues, please [[phab:T352232|share them with the team on Phabricator]]. '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The Toolforge [[wikitech:News/Toolforge Grid Engine deprecation|Grid Engine shutdown process]] will start on December 14. Maintainers of [[toolforge:grid-deprecation|tools that still use this old system]] should plan to migrate to Kubernetes, or tell the team your plans on Phabricator in the task about your tool, before that date. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/VIWWQKMSQO2ED3TVUR7KPPWRTOBYBVOA/] * Communities using [[mw:Special:MyLanguage/Structured_Discussions|Structured Discussions]] are being contacted regarding [[mw:Special:MyLanguage/Structured_Discussions/Deprecation|the upcoming deprecation of Structured Discussions]]. You can read more about this project, and share your comments, [[mw:Special:MyLanguage/Structured_Discussions/Deprecation|on the project's page]]. '''Events''' * Registration & Scholarship applications are now open for the [[mw:Special:MyLanguage/Wikimedia Hackathon 2024|Wikimedia Hackathon 2024]] that will take place from 3–5 May in Tallinn, Estonia. Scholarship applications are open until 5 January 2024. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/49|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W49"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:50, 4 December 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25914435 --> == Tech News: 2023-50 == <section begin="technews-2023-W50"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/50|Translations]] are available. '''Recent changes''' * On Wikimedia Commons, there are some minor user-interface improvements for the "choosing own vs not own work" step in the UploadWizard. This is part of the Structured Content team's project of [[:commons:Commons:WMF support for Commons/Upload Wizard Improvements|improving UploadWizard on Commons]]. [https://phabricator.wikimedia.org/T352707][https://phabricator.wikimedia.org/T352709] '''Problems''' * There was a problem showing the [[mw:Special:MyLanguage/Growth/Personalized first day/Newcomer homepage|Newcomer homepage]] feature with the "impact module" and their page-view graphs, for a few days in early December. This has now been fixed. [https://phabricator.wikimedia.org/T352352][https://phabricator.wikimedia.org/T352349] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.9|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-12-12|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-12-13|en}}. It will be on all wikis from {{#time:j xg|2023-12-14|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Future changes''' * [[File:Octicons-tools.svg|15px|link=]] The [https://wikimediafoundation.limesurvey.net/796964 2023 Developer Satisfaction Survey] is seeking the opinions of the Wikimedia developer community. Please take the survey if you have any role in developing software for the Wikimedia ecosystem. The survey is open until 5 January 2024, and has an associated [[foundation:Legal:December_2023_Developer_Satisfaction_Survey|privacy statement]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/50|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W50"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 02:12, 12 December 2023 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25945501 --> == Tech News: 2023-51 == <section begin="technews-2023-W51"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2023/51|Translations]] are available. '''Tech News''' * The next issue of Tech News will be sent out on 8 January 2024 because of [[w:en:Christmas and holiday season|the holidays]]. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.10|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2023-12-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2023-12-20|en}}. It will be on all wikis from {{#time:j xg|2023-12-21|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). There is no new MediaWiki version next week. [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * Starting December 18, it won't be possible to activate Structured Discussions on a user's own talk page using the Beta feature. The Beta feature option remains available for users who want to deactivate Structured Discussions. This is part of [[mw:Structured Discussions/Deprecation|Structured Discussions' deprecation work]]. [https://phabricator.wikimedia.org/T248309] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] There will be full support for redirects in the Module namespace. The "Move Page" feature will leave an appropriate redirect behind, and such redirects will be appropriately recognized by the software (e.g. hidden from [[{{#special:UnconnectedPages}}]]). There will also be support for [[mw:Special:MyLanguage/Extension:Scribunto/Lua reference manual#Renaming or moving modules|manual redirects]]. [https://phabricator.wikimedia.org/T120794] '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The MediaWiki JavaScript documentation is moving to a new format. During the move, you can read the old docs using [https://doc.wikimedia.org/mediawiki-core/REL1_41/js/ version 1.41]. Feedback about [https://doc.wikimedia.org/mediawiki-core/master/js/ the new site] is welcome on the [[mw:Talk:JSDoc_WMF_theme|project talk page]]. * The Wishathon is a new initiative that encourages collaboration across the Wikimedia community to develop solutions for wishes collected through the [[m:Special:MyLanguage/Community Wishlist Survey|Community Wishlist Survey]]. The first community Wishathon will take place from 15–17 March. If you are interested in a project proposal as a user, developer, designer, or product lead, you can [[m:Special:MyLanguage/Event:WishathonMarch2024|register for the event and read more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2023/51|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2023-W51"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:17, 18 December 2023 (UTC) <!-- Message sent by User:Johan (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=25959059 --> == Tech News: 2024-02 == <section begin="technews-2024-W02"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/02|Translations]] are available. '''Recent changes''' * [https://mediawiki2latex.wmflabs.org/ mediawiki2latex] is a tool that converts wiki content into the formats of LaTeX, PDF, ODT, and EPUB. The code now runs many times faster due to recent improvements. There is also an optional Docker container you can [[b:de:Benutzer:Dirk_Hünniger/wb2pdf/install#Using_Docker|install]] on your local machine. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The way that Random pages are selected has been updated. This will slowly reduce the problem of some pages having a lower chance of appearing. [https://phabricator.wikimedia.org/T309477] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.13|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-01-09|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-01-10|en}}. It will be on all wikis from {{#time:j xg|2024-01-11|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/02|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W02"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:19, 9 January 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26026251 --> == Tech News: 2024-03 == <section begin="technews-2024-W03"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/03|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Pages that use the JSON [[mw:Special:MyLanguage/Manual:ContentHandler|contentmodel]] will now use tabs instead of spaces for auto-indentation. This will significantly reduce the page size. [https://phabricator.wikimedia.org/T326065] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] [[mw:Special:MyLanguage/Extension:Gadgets|Gadgets]] and personal user scripts may now use JavaScript syntax introduced in ES6 (also known as "ES2015") and ES7 ("ES2016"). MediaWiki validates the source code to protect other site functionality from syntax errors, and to ensure scripts are valid in all [[mw:Special:MyLanguage/Compatibility#Browsers|supported browsers]]. Previously, Gadgets could use the <bdi lang="zxx" dir="ltr"><code><nowiki>requiresES6</nowiki></code></bdi> option. This option is no longer needed and will be removed in the future. [https://phabricator.wikimedia.org/T75714] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] [[mw:Special:MyLanguage/Manual:Bot passwords|Bot passwords]] and [[mw:Special:MyLanguage/OAuth/Owner-only consumers|owner-only OAuth consumers]] can now be restricted to allow editing only specific pages. [https://phabricator.wikimedia.org/T349957] * You can now [[mw:Special:MyLanguage/Extension:Thanks|thank]] edits made by bots. [https://phabricator.wikimedia.org/T341388] * An update on the status of the Community Wishlist Survey for 2024 [[m:Special:MyLanguage/Community Wishlist Survey/Future Of The Wishlist/January 4, 2024 Update|has been published]]. Please read and give your feedback. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.14|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-01-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-01-17|en}}. It will be on all wikis from {{#time:j xg|2024-01-18|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * Starting on January 17, it will not be possible to login to Wikimedia wikis from some specific old versions of the Chrome browser (versions 51–66, released between 2016 and 2018). Additionally, users of iOS 12, or Safari on Mac OS 10.14, may need to login to each wiki separately. [https://phabricator.wikimedia.org/T344791] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The <bdi lang="zxx" dir="ltr"><code>jquery.cookie</code></bdi> module was deprecated and replaced with the <bdi lang="zxx" dir="ltr"><code>mediawiki.cookie</code></bdi> module last year. A script has now been run to replace any remaining uses, and this week the temporary alias will be removed. [https://phabricator.wikimedia.org/T354966] '''Future changes''' * Wikimedia Deutschland is working to [[m:WMDE Technical Wishes/Reusing references|make reusing references easier]]. They are looking for people who are interested in participating in [https://wikimedia.sslsurvey.de/User-research-into-Reusing-References-Sign-up-Form-2024/en/ individual video calls for user research in January and February]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/03|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W03"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:13, 16 January 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26074460 --> == Tech News: 2024-04 == <section begin="technews-2024-W04"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/04|Translations]] are available. '''Problems''' * A bug in UploadWizard prevented linking to the userpage of the uploader when uploading. It has now been fixed. [https://phabricator.wikimedia.org/T354529] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.15|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-01-23|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-01-24|en}}. It will be on all wikis from {{#time:j xg|2024-01-25|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/04|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W04"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:03, 23 January 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26096197 --> == Tech News: 2024-05 == <section begin="technews-2024-W05"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/05|Translations]] are available. '''Recent changes''' * Starting Monday January 29, all talk pages messages' timestamps will become a link. This link is a permanent link to the comment. It allows users to find the comment they are looking for, even if this comment was moved elsewhere. This will affect all wikis except for the English Wikipedia. You can read more about this change [https://diff.wikimedia.org/2024/01/29/talk-page-permalinks-dont-lose-your-threads/ on Diff] or [[mw:Special:MyLanguage/Help:DiscussionTools#Talk_pages_permalinking|on Mediawiki.org]].<!-- The Diff post will be published on Monday morning UTC--> [https://phabricator.wikimedia.org/T302011] * There are some improvements to the CAPTCHA to make it harder for spam bots and scripts to bypass it. If you have feedback on this change, please comment on [[phab:T141490|the task]]. Staff are monitoring metrics related to the CAPTCHA, as well as secondary metrics such as account creations and edit counts. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.16|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-01-30|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-01-31|en}}. It will be on all wikis from {{#time:j xg|2024-02-01|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] On February 1, a link will be added to the "Tools" menu to download a [[w:en:QR code|QR code]] that links to the page you are viewing. There will also be a new [[{{#special:QrCode}}]] page to create QR codes for any Wikimedia URL. This addresses the [[m:Community Wishlist Survey 2023/Mobile and apps/Add ability to share QR code for a page in any Wikimedia project|#19 most-voted wish]] from the [[m:Community Wishlist Survey 2023/Results|2023 Community Wishlist Survey]]. [https://phabricator.wikimedia.org/T329973] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] [[mw:Special:MyLanguage/Extension:Gadgets|Gadgets]] which only work in some skins have sometimes used the <bdi lang="zxx" dir="ltr"><code>targets</code></bdi> option to limit where you can use them. This will stop working this week. You should use the <bdi lang="zxx" dir="ltr"><code>skins</code></bdi> option instead. [https://phabricator.wikimedia.org/T328497] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/05|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W05"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:31, 29 January 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26137870 --> == Tech News: 2024-06 == <section begin="technews-2024-W06"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/06|Translations]] are available. '''Recent changes''' *The mobile site history pages now use the same HTML as the desktop history pages. If you hear of any problems relating to mobile history usage please point them to [[phab:T353388|the phabricator task]]. *On most wikis, admins can now block users from making specific actions. These actions are: uploading files, creating new pages, moving (renaming) pages, and sending thanks. The goal of this feature is to allow admins to apply blocks that are adequate to the blocked users' activity. [[m:Special:MyLanguage/Community health initiative/Partial blocks#action-blocks|Learn more about "action blocks"]]. [https://phabricator.wikimedia.org/T242541][https://phabricator.wikimedia.org/T280531] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.17|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-02-06|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-02-07|en}}. It will be on all wikis from {{#time:j xg|2024-02-08|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * Talk pages permalinks that included diacritics and non-Latin script were malfunctioning. This issue is fixed. [https://phabricator.wikimedia.org/T356199] '''Future changes''' * [[m:WMDE Technical Wishes/ReferencePreviews#24WPs|24 Wikipedias]] with [[mw:Special:MyLanguage/Reference_Tooltips|Reference Tooltips]] as a default gadget are encouraged to remove that default flag. This would make [[mw:Special:MyLanguage/Help:Reference_Previews|Reference Previews]] the new default for reference popups, leading to a more consistent experience across wikis. For [[m:WMDE Technical Wishes/ReferencePreviews#46WPs|46 Wikipedias]] with less than 4 interface admins, the change is already scheduled for mid-February, [[m:Talk:WMDE Technical Wishes/ReferencePreviews#Reference Previews to become the default for previewing references on more wikis.|unless there are concerns]]. The older Reference Tooltips gadget will still remain usable and will override this feature, if it is available on your wiki and you have enabled it in your settings. [https://meta.wikimedia.org/wiki/WMDE_Technical_Wishes/ReferencePreviews#Reference_Previews_to_become_the_default_for_previewing_references_on_more_wikis][https://phabricator.wikimedia.org/T355312] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/06|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W06"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:22, 5 February 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26180971 --> == Tech News: 2024-07 == <section begin="technews-2024-W07"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/07|Translations]] are available. '''Recent changes''' * The [[d:Wikidata:SPARQL query service/WDQS graph split|WDQS Graph Split experiment]] is working and loaded onto 3 test servers. The team in charge is testing the split's impact and requires feedback from WDQS users through the UI or programmatically in different channels. [https://www.wikidata.org/wiki/Wikidata_talk:SPARQL_query_service/WDQS_graph_split][https://phabricator.wikimedia.org/T356773][https://www.wikidata.org/wiki/User:Sannita_(WMF)] Users' feedback will validate the impact of various use cases and workflows around the Wikidata Query service. [https://www.wikidata.org/wiki/Wikidata:SPARQL_query_service/WDQS_backend_update/October_2023_scaling_update][https://www.mediawiki.org/wiki/Wikidata_Query_Service/User_Manual#Federation] '''Problems''' *There was a bug that affected the appearance of visited links when using mobile device to access wiki sites. It made the links appear black; [[phab:T356928|this issue]] is fixed. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.18|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-02-13|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-02-14|en}}. It will be on all wikis from {{#time:j xg|2024-02-15|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] As work continues on the grid engine deprecation,[https://wikitech.wikimedia.org/wiki/News/Toolforge_Grid_Engine_deprecation] tools on the grid engine will be stopped starting on February 14th, 2024. If you have tools actively migrating you can ask for an extension so they are not stopped. [https://wikitech.wikimedia.org/wiki/Portal:Toolforge/About_Toolforge#Communication_and_support] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/07|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W07"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 05:48, 13 February 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26223994 --> == Tech News: 2024-08 == <section begin="technews-2024-W08"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/08|Translations]] are available. '''Recent changes''' * If you have the "{{int:Tog-enotifwatchlistpages}}" option enabled, edits by bot accounts no longer trigger notification emails. Previously, only minor edits would not trigger the notification emails. [https://phabricator.wikimedia.org/T356984] * There are changes to how user and site scripts load for [[mw:Special:MyLanguage/Skin:Vector/2022| Vector 2022]] on specific wikis. The changes impacted the following Wikis: all projects with [[mw:Special:MyLanguage/Skin:Vector|Vector legacy]] as the default skin, Wikivoyage, and Wikibooks. Other wikis will be affected over the course of the next three months. Gadgets are not impacted. If you have been affected or want to minimize the impact on your project, see [[Phab:T357580| this ticket]]. Please coordinate and take action proactively. *Newly auto-created accounts (the accounts you get when you visit a new wiki) now have the same local notification preferences as users who freshly register on that wiki. It is effected in four notification types listed in the [[phab:T353225|task's description]]. *The maximum file size when using [[c:Special:MyLanguage/Commons:Upload_Wizard|Upload Wizard]] is now 5 GiB. [https://phabricator.wikimedia.org/T191804] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.19|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-02-20|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-02-21|en}}. It will be on all wikis from {{#time:j xg|2024-02-22|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Selected tools on the grid engine have been [[wikitech:News/Toolforge_Grid_Engine_deprecation|stopped]] as we prepare to shut down the grid on March 14th, 2024. The tool's code and data have not been deleted. If you are a maintainer and you want your tool re-enabled reach out to the [[wikitech:Portal:Toolforge/About_Toolforge#Communication_and_support|team]]. Only tools that have asked for extension are still running on the grid. * The CSS <bdi lang="zxx" dir="ltr"><code>[https://developer.mozilla.org/en-US/docs/Web/CSS/filter filter]</code></bdi> property can now be used in HTML <bdi lang="zxx" dir="ltr"><code>style</code></bdi> attributes in wikitext. [https://phabricator.wikimedia.org/T308160] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/08|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W08"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 15:36, 19 February 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26254282 --> == Tech News: 2024-09 == <section begin="technews-2024-W09"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/09|Translations]] are available. '''Recent changes''' * The [[mw:Special:MyLanguage/VisualEditor_on_mobile|mobile visual editor]] is now the default editor for users who never edited before, at a small group of wikis. [[mw:Special:MyLanguage/VisualEditor_on_mobile/VE_mobile_default#A/B_test_results| Research ]] shows that users using this editor are slightly more successful publishing the edits they started, and slightly less successful publishing non-reverted edits. Users who defined the wikitext editor as their default on desktop will get the wikitext editor on mobile for their first edit on mobile as well. [https://phabricator.wikimedia.org/T352127] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The [[mw:Special:MyLanguage/ResourceLoader/Core modules#mw.config|mw.config]] value <code>wgGlobalGroups</code> now only contains groups that are active in the wiki. Scripts no longer have to check whether the group is active on the wiki via an API request. A code example of the above is: <bdi lang="zxx" dir="ltr"><code>if (/globalgroupname/.test(mw.config.get("wgGlobalGroups")))</code></bdi>. [https://phabricator.wikimedia.org/T356008] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.20|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-02-27|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-02-28|en}}. It will be on all wikis from {{#time:j xg|2024-02-29|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Future changes''' * The right to change [[mw:Special:MyLanguage/Manual:Tags|edit tags]] (<bdi lang="zxx" dir="ltr"><code>changetags</code></bdi>) will be removed from users in Wikimedia sites, keeping it by default for admins and bots only. Your community can ask to retain the old configuration on your wiki before this change happens. Please indicate in [[phab:T355639|this ticket]] to keep it for your community before the end of March 2024. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/09|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W09"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:23, 26 February 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26294125 --> == Tech News: 2024-10 == <section begin="technews-2024-W10"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/10|Translations]] are available. '''Recent changes''' * The <bdi lang="zxx" dir="ltr"><code>Special:Book</code></bdi> page (as well as the associated "Create a book" functionality) provided by the old [[mw:Special:MyLanguage/Extension:Collection|Collection extension]] has been removed from all Wikisource wikis, as it was broken. This does not affect the ability to download normal books, which is provided by the [[mw:Special:MyLanguage/Extension:Wikisource|Wikisource extension]]. [https://phabricator.wikimedia.org/T358437] * [[m:Wikitech|Wikitech]] now uses the next-generation [[mw:Special:MyLanguage/Parsoid|Parsoid]] wikitext parser by default to generate all pages in the Talk namespace. Report any problems on the [[mw:Talk:Parsoid/Parser_Unification/Known_Issues|Known Issues discussion page]]. You can use the [[mw:Special:MyLanguage/Extension:ParserMigration|ParserMigration]] extension to control the use of Parsoid; see the [[mw:Special:MyLanguage/Help:Extension:ParserMigration|ParserMigration help documentation]] for more details. * Maintenance on [https://etherpad.wikimedia.org etherpad] is completed. If you encounter any issues, please indicate in [[phab:T316421|this ticket]]. * [[File:Octicons-tools.svg|12px|link=|alt=| Advanced item]] [[mw:Special:MyLanguage/Extension:Gadgets|Gadgets]] allow interface admins to create custom features with CSS and JavaScript. The <bdi lang="zxx" dir="ltr"><code>Gadget</code></bdi> and <bdi lang="zxx" dir="ltr"><code>Gadget_definition</code></bdi> namespaces and <bdi lang="zxx" dir="ltr"><code>gadgets-definition-edit</code></bdi> user right were reserved for an experiment in 2015, but were never used. These were visible on Special:Search and Special:ListGroupRights. The unused namespaces and user rights are now removed. No pages are moved, and no changes need to be made. [https://phabricator.wikimedia.org/T31272] * A usability improvement to the "Add a citation" in Wikipedia workflow has been made, the insert button was moved to the popup header. [https://phabricator.wikimedia.org/T354847] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.21|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-03-05|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-03-06|en}}. It will be on all wikis from {{#time:j xg|2024-03-07|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Future changes''' * All wikis will be read-only for a few minutes on March 20. This is planned at 14:00 UTC. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T358233] * The HTML markup of headings and section edit links will be changed later this year to improve accessibility. See [[mw:Special:MyLanguage/Heading_HTML_changes|Heading HTML changes]] for details. The new markup will be the same as in the new Parsoid wikitext parser. You can test your gadget or stylesheet with the new markup if you add <bdi lang="zxx" dir="ltr"><code>?useparsoid=1</code></bdi> to your URL ([[mw:Special:MyLanguage/Help:Extension:ParserMigration#Selecting_a_parser_using_a_URL_query_string|more info]]) or turn on Parsoid read views in your user options ([[mw:Special:MyLanguage/Help:Extension:ParserMigration#Enabling_via_user_preference|more info]]). * '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/10|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W10"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:47, 4 March 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26329807 --> == Tech News: 2024-11 == <section begin="technews-2024-W11"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/11|Translations]] are available. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.22|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-03-12|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-03-13|en}}. It will be on all wikis from {{#time:j xg|2024-03-14|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * After consulting with various communities, the line height of the text on the [[mw:Special:MyLanguage/Skin:Minerva Neue|Minerva skin]] will be increased to its previous value of 1.65. Different options for typography can also be set using the options in the menu, as needed. [https://phabricator.wikimedia.org/T358498] *The active link color in [[mw:Special:MyLanguage/Skin:Minerva Neue|Minerva]] will be changed to provide more consistency with our other platforms and best practices. [https://phabricator.wikimedia.org/T358516] * [[c:Special:MyLanguage/Commons:Structured data|Structured data on Commons]] will no longer ask whether you want to leave the page without saving. This will prevent the “information you’ve entered may not be saved” popups from appearing when no information have been entered. It will also make file pages on Commons load faster in certain cases. However, the popups will be hidden even if information has indeed been entered. If you accidentally close the page before saving the structured data you entered, that data will be lost. [https://phabricator.wikimedia.org/T312315] '''Future changes''' * All wikis will be read-only for a few minutes on March 20. This is planned at 14:00 UTC. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T358233][https://meta.wikimedia.org/wiki/Special:MyLanguage/Tech/Server_switch] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/11|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W11"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:04, 11 March 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26374013 --> == Tech News: 2024-12 == <section begin="technews-2024-W12"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/12|Translations]] are available. '''Recent changes''' * The notice "Language links are at the top of the page" that appears in the [[mw:Special:MyLanguage/Skin:Vector/2022|Vector 2022 skin]] main menu has been removed now that users have learned the new location of the Language switcher. [https://phabricator.wikimedia.org/T353619] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] [[m:Special:MyLanguage/IP_Editing:_Privacy_Enhancement_and_Abuse_Mitigation/IP_Info_feature|IP info feature]] displays data from Spur, an IP addresses database. Previously, the only data source for this feature was MaxMind. Now, IP info is more useful for patrollers. [https://phabricator.wikimedia.org/T341395] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The Toolforge Grid Engine services have been shut down after the final migration process from Grid Engine to Kubernetes. [https://wikitech.wikimedia.org/wiki/Obsolete:Toolforge/Grid][https://wikitech.wikimedia.org/wiki/News/Toolforge_Grid_Engine_deprecation][https://techblog.wikimedia.org/2022/03/14/toolforge-and-grid-engine/] * Communities can now customize the default reasons for undeleting a page by creating [[MediaWiki:Undelete-comment-dropdown]]. [https://phabricator.wikimedia.org/T326746] '''Problems''' * [[m:Special:MyLanguage/WMDE_Technical_Wishes/RevisionSlider|RevisionSlider]] is an interface to interactively browse a page's history. Users in [[mw:Special:MyLanguage/Extension:RevisionSlider/Developing_a_RTL-accessible_feature_in_MediaWiki_-_what_we%27ve_learned_while_creating_the_RevisionSlider|right-to-left]] languages reported RevisionSlider reacting wrong to mouse clicks. This should be fixed now. [https://phabricator.wikimedia.org/T352169] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.23|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-03-19|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-03-20|en}}. It will be on all wikis from {{#time:j xg|2024-03-21|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * All wikis will be read-only for a few minutes on March 20. This is planned at [https://zonestamp.toolforge.org/1710943200 14:00 UTC]. [https://phabricator.wikimedia.org/T358233][https://meta.wikimedia.org/wiki/Special:MyLanguage/Tech/Server_switch] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/12|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W12"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:39, 18 March 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26410165 --> == Tech News: 2024-13 == <section begin="technews-2024-W13"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/13|Translations]] are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] An update was made on March 18th 2024 to how various projects load site, user JavaScript and CSS in [[mw:Special:MyLanguage/Skin:Vector/2022|Vector 2022 skin]]. A [[phab:T360384|checklist]] is provided for site admins to follow. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.24|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-03-26|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-03-27|en}}. It will be on all wikis from {{#time:j xg|2024-03-28|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/13|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W13"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:56, 25 March 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26446209 --> == Tech News: 2024-14 == <section begin="technews-2024-W14"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/14|Translations]] are available. '''Recent changes''' * Users of the [[mw:Special:MyLanguage/Reading/Web/Accessibility_for_reading|reading accessibility]] beta feature will notice that the default line height for the standard and large text options has changed. [https://phabricator.wikimedia.org/T359030] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.25|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-04-02|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-04-03|en}}. It will be on all wikis from {{#time:j xg|2024-04-04|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Future changes''' * The Wikimedia Foundation has an annual plan. The annual plan decides what the Wikimedia Foundation will work on. You can now read [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2024-2025/Product & Technology OKRs#Draft Key Results|the draft key results]] for the Product and Technology department. They are suggestions for what results the Foundation wants from big technical changes from July 2024 to June 2025. You can [[m:Talk:Wikimedia Foundation Annual Plan/2024-2025/Product & Technology OKRs|comment on the talk page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/14|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W14"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 03:36, 2 April 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26462933 --> == Tech News: 2024-15 == <section begin="technews-2024-W15"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/15|Translations]] are available. '''Recent changes''' * Web browsers can use tools called [[:w:en:Browser extension|extensions]]. There is now a Chrome extension called [[m:Future Audiences/Experiment:Citation Needed|Citation Needed]] which you can use to see if an online statement is supported by a Wikipedia article. This is a small experiment to see if Wikipedia can be used this way. Because it is a small experiment, it can only be used in Chrome in English. * [[File:Octicons-gift.svg|12px|link=|alt=|Wishlist item]] A new [[mw:Special:MyLanguage/Help:Edit Recovery|Edit Recovery]] feature has been added to all wikis, available as a [[Special:Preferences#mw-prefsection-editing|user preference]]. Once you enable it, your in-progress edits will be stored in your web browser, and if you accidentally close an editing window or your browser or computer crashes, you will be prompted to recover the unpublished text. Please leave any feedback on the [[m:Special:MyLanguage/Talk:Community Wishlist Survey 2023/Edit-recovery feature|project talk page]]. This was the #8 wish in the 2023 Community Wishlist Survey. * Initial results of [[mw:Special:MyLanguage/Edit check|Edit check]] experiments [[mw:Special:MyLanguage/Edit_check#4_April_2024|have been published]]. Edit Check is now deployed as a default feature at [[phab:T342930#9538364|the wikis that tested it]]. [[mw:Talk:Edit check|Let us know]] if you want your wiki to be part of the next deployment of Edit check. [https://phabricator.wikimedia.org/T342930][https://phabricator.wikimedia.org/T361727] * Readers using the [[mw:Special:MyLanguage/Skin:Minerva Neue|Minerva skin]] on mobile will notice there has been an improvement in the line height across all typography settings. [https://phabricator.wikimedia.org/T359029] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.42/wmf.26|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-04-09|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-04-10|en}}. It will be on all wikis from {{#time:j xg|2024-04-11|en}} ([[mw:MediaWiki 1.42/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * New accounts and logged-out users will get the [[mw:Special:MyLanguage/VisualEditor|visual editor]] as their default editor on mobile. This deployment is made at all wikis except for the English Wikipedia. [https://phabricator.wikimedia.org/T361134] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/15|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W15"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:37, 8 April 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26564838 --> == Tech News: 2024-16 == <section begin="technews-2024-W16"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/16|Translations]] are available. '''Problems''' * Between 2 April and 8 April, on wikis using [[mw:Special:MyLanguage/Extension:FlaggedRevs|Flagged Revisions]], the "{{Int:tag-mw-reverted}}" tag was not applied to undone edits. In addition, page moves, protections and imports were not autoreviewed. This problem is now fixed. [https://phabricator.wikimedia.org/T361918][https://phabricator.wikimedia.org/T361940] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.1|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-04-16|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-04-17|en}}. It will be on all wikis from {{#time:j xg|2024-04-18|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[mw:Special:MyLanguage/Help:Magic words#DEFAULTSORT|Default category sort keys]] will now affect categories added by templates placed in [[mw:Special:MyLanguage/Help:Cite|footnotes]]. Previously footnotes used the page title as the default sort key even if a different default sort key was specified (category-specific sort keys already worked). [https://phabricator.wikimedia.org/T40435] * A new variable <bdi lang="zxx" dir="ltr"><code>page_last_edit_age</code></bdi> will be added to [[Special:AbuseFilter|abuse filters]]. It tells how many seconds ago the last edit to a page was made. [https://phabricator.wikimedia.org/T269769] '''Future changes''' * Volunteer developers are kindly asked to update the code of their tools and features to handle [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]]. [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/For developers/2024-04 CTA|Learn more]]. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Four database fields will be removed from database replicas (including [[quarry:|Quarry]]). This affects only the <bdi lang="zxx" dir="ltr"><code>abuse_filter</code></bdi> and <bdi lang="zxx" dir="ltr"><code>abuse_filter_history</code></bdi> tables. Some queries might need to be updated. [https://phabricator.wikimedia.org/T361996] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/16|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W16"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:29, 15 April 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26564838 --> == Tech News: 2024-17 == <section begin="technews-2024-W17"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/17|Translations]] are available. '''Recent changes''' * Starting this week, newcomers editing Wikipedia [[mw:Special:MyLanguage/Growth/Positive reinforcement#Leveling up 3|will be encouraged]] to try structured tasks. [[mw:Special:MyLanguage/Growth/Feature summary#Newcomer tasks|Structured tasks]] have been shown to [[mw:Special:MyLanguage/Growth/Personalized first day/Structured tasks/Add a link/Experiment analysis, December 2021|improve newcomer activation and retention]]. [https://phabricator.wikimedia.org/T348086] * You can [[m:Special:MyLanguage/Coolest Tool Award|nominate your favorite tools]] for the fifth edition of the Coolest Tool Award. Nominations will be open until May 10. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.2|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-04-23|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-04-24|en}}. It will be on all wikis from {{#time:j xg|2024-04-25|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Future changes''' * This is the last warning that by the end of May 2024 the Vector 2022 skin will no longer share site and user scripts/styles with old Vector. For user-scripts that you want to keep using on Vector 2022, copy the contents of [[{{#special:MyPage}}/vector.js]] to [[{{#special:MyPage}}/vector-2022.js]]. There are [[mw:Special:MyLanguage/Reading/Web/Desktop Improvements/Features/Loading Vector 2010 scripts|more technical details]] available. Interface administrators who foresee this leading to lots of technical support questions may wish to send a mass message to your community, as was done on French Wikipedia. [https://phabricator.wikimedia.org/T362701] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/17|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W17"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:28, 22 April 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26647188 --> == Tech News: 2024-18 == <section begin="technews-2024-W18"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/18|Translations]] are available. '''Recent changes''' [[File:Talk_pages_default_look_(April_2023).jpg|thumb|alt=Screenshot of the visual improvements made on talk pages|Example of a talk page with the new design, in French.]] * The appearance of talk pages changed for the following wikis: {{int:project-localized-name-azwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-dewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-fawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hiwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-idwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ptwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-rowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-thwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-trwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ukwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-viwiki/en}}. These wikis participated to a test, where 50% of users got the new design, for one year. As this test [[Mw:Special:MyLanguage/Talk pages project/Usability/Analysis|gave positive results]], the new design is deployed on these wikis as the default design. It is possible to opt-out these changes [[Special:Preferences#mw-prefsection-editing|in user preferences]] ("{{int:discussiontools-preference-visualenhancements}}"). The deployment will happen at all wikis in the coming weeks. [https://phabricator.wikimedia.org/T341491] * Seven new wikis have been created: ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q33014|Betawi]] ([[w:bew:|<code>w:bew:</code>]]) [https://phabricator.wikimedia.org/T357866] ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q35708|Kusaal]] ([[w:kus:|<code>w:kus:</code>]]) [https://phabricator.wikimedia.org/T359757] ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q35513|Igala]] ([[w:igl:|<code>w:igl:</code>]]) [https://phabricator.wikimedia.org/T361644] ** a {{int:project-localized-name-group-wiktionary}} in [[d:Q33541|Karakalpak]] ([[wikt:kaa:|<code>wikt:kaa:</code>]]) [https://phabricator.wikimedia.org/T362135] ** a {{int:project-localized-name-group-wikisource}} in [[d:Q9228|Burmese]] ([[s:my:|<code>s:my:</code>]]) [https://phabricator.wikimedia.org/T361085] ** a {{int:project-localized-name-group-wikisource}} in [[d:Q9237|Malay]] ([[s:ms:|<code>s:ms:</code>]]) [https://phabricator.wikimedia.org/T363039] ** a {{int:project-localized-name-group-wikisource}} in [[d:Q8108|Georgian]] ([[s:ka:|<code>s:ka:</code>]]) [https://phabricator.wikimedia.org/T363085] * You can now [https://translatewiki.net/wiki/Support#Early_access:_Watch_Message_Groups_on_Translatewiki.net watch message groups/projects] on [[m:Special:MyLanguage/translatewiki.net|Translatewiki.net]]. Initially, this feature will notify you of added or deleted messages in these groups. [https://phabricator.wikimedia.org/T348501] * Dark mode is now available on all wikis, on mobile web for logged-in users who opt into the [[Special:MobileOptions|advanced mode]]. This is the early release of the feature. Technical editors are invited to [https://night-mode-checker.wmcloud.org/ check for accessibility issues on wikis]. See [[mw:Special:MyLanguage/Reading/Web/Accessibility for reading/Updates/2024-04|more detailed guidelines]]. '''Problems''' * [[mw:Special:MyLanguage/Help:Extension:Kartographer|Kartographer]] maps can use an alternative visual style without labels, by using <bdi lang="zxx" dir="ltr"><code><nowiki>mapstyle="osm"</nowiki></code></bdi>. This wasn't working in previews, creating the wrong impression that it wasn't supported. This has now been fixed. [https://phabricator.wikimedia.org/T362531] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.3|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-04-30|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-05-01|en}}. It will be on all wikis from {{#time:j xg|2024-05-02|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/18|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W18"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 03:33, 30 April 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26689057 --> == Tech News: 2024-19 == <section begin="technews-2024-W19"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/19|Translations]] are available. '''Recent changes''' [[File:Talk_pages_default_look_(April_2023).jpg|thumb|alt=Screenshot of the visual improvements made on talk pages|Example of a talk page with the new design, in French.]] * The appearance of talk pages changed for all wikis, except for Commons, Wikidata and most Wikipedias ([[m:Special:MyLanguage/Tech/News/2024/18|a few]] have already received this design change). You can read the detail of the changes [[diffblog:2024/05/02/making-talk-pages-better-for-everyone/|on ''Diff'']]. It is possible to opt-out these changes [[Special:Preferences#mw-prefsection-editing|in user preferences]] ("{{int:discussiontools-preference-visualenhancements}}"). The deployment will happen at remaining wikis in the coming weeks. [https://phabricator.wikimedia.org/T352087][https://phabricator.wikimedia.org/T319146] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Interface admins now have greater control over the styling of article components on mobile with the introduction of the <code>SiteAdminHelper</code>. More information on how styles can be disabled can be found [[mw:Special:MyLanguage/Extension:WikimediaMessages#Site_admin_helper|at the extension's page]]. [https://phabricator.wikimedia.org/T363932] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] [[m:Special:MyLanguage/Wikimedia Enterprise|Wikimedia Enterprise]] has added article body sections in JSON format and a curated short description field to the existing parsed Infobox. This expansion to the API is also available via Wikimedia Cloud Services. [https://enterprise.wikimedia.com/blog/article-sections-and-description/] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.4|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-05-07|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-05-08|en}}. It will be on all wikis from {{#time:j xg|2024-05-09|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * When you look at the Special:Log page, the first view is labelled "All public logs", but it only shows some logs. This label will now say "Main public logs". [https://phabricator.wikimedia.org/T237729] '''Future changes''' * A new service will be built to replace [[mw:Special:MyLanguage/Extension:Graph|Extension:Graph]]. Details can be found in [[mw:Special:MyLanguage/Extension:Graph/Plans|the latest update]] regarding this extension. * Starting May 21, English Wikipedia and German Wikipedia will get the possibility to activate "[[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]]". This is part of the [[phab:T304110|progressive deployment of this tool to all Wikipedias]]. These communities can [[mw:Special:MyLanguage/Growth/Community configuration|activate and configure the feature locally]]. [https://phabricator.wikimedia.org/T308144] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/19|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W19"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:44, 6 May 2024 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26729363 --> == Tech News: 2024-20 == <section begin="technews-2024-W20"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/20|Translations]] are available. '''Recent changes''' * On Wikisource there is a special page listing pages of works without corresponding scan images. Now you can use the new magic word <bdi lang="zxx" dir="ltr"><code>__EXPECTWITHOUTSCANS__</code></bdi> to exclude certain pages (list of editions or translations of works) from that list. [https://phabricator.wikimedia.org/T344214] * If you use the [[Special:Preferences#mw-prefsection-editing|user-preference]] "{{int:tog-uselivepreview}}", then the template-page feature "{{int:Templatesandbox-editform-legend}}" will now also work without reloading the page. [https://phabricator.wikimedia.org/T136907] * [[mw:Special:Mylanguage/Extension:Kartographer|Kartographer]] maps can now specify an alternative text via the <bdi lang="zxx" dir="ltr"><code><nowiki>alt=</nowiki></code></bdi> attribute. This is identical in usage to the <bdi lang="zxx" dir="ltr"><code><nowiki>alt=</nowiki></code></bdi> attribute in the [[mw:Special:MyLanguage/Help:Images#Syntax|image and gallery syntax]]. An exception for this feature is wikis like Wikivoyage where the miniature maps are interactive. [https://phabricator.wikimedia.org/T328137] * The old [[mw:Special:MyLanguage/Extension:GuidedTour|Guided Tour]] for the "[[mw:Special:MyLanguage/Edit Review Improvements/New filters for edit review|New Filters for Edit Review]]" feature has been removed. It was created in 2017 to show people with older accounts how the interface had changed, and has now been seen by most of the intended people. [https://phabricator.wikimedia.org/T217451] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.5|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-05-14|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-05-15|en}}. It will be on all wikis from {{#time:j xg|2024-05-16|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The [[{{#special:search}}]] results page will now use CSS flex attributes, for better accessibility, instead of a table. If you have a gadget or script that adjusts search results, you should update your script to the new HTML structure. [https://phabricator.wikimedia.org/T320295] '''Future changes''' * In the Vector 2022 skin, main pages will be displayed at full width (like special pages). The goal is to keep the number of characters per line large enough. This is related to the coming changes to typography in Vector 2022. [[mw:Special:MyLanguage/Reading/Web/Accessibility for reading/Updates|Learn more]]. [https://phabricator.wikimedia.org/T357706] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Two columns of the <bdi lang="zxx" dir="ltr"><code>[[mw:Special:MyLanguage/Manual:pagelinks table|pagelinks]]</code></bdi> database table (<bdi lang="zxx" dir="ltr"><code>pl_namespace</code></bdi> and <bdi lang="zxx" dir="ltr"><code>pl_title</code></bdi>) are being dropped soon. Users must use two columns of the new <bdi lang="zxx" dir="ltr"><code>[[mw:special:MyLanguage/Manual:linktarget table|linktarget]]</code></bdi> table instead (<bdi lang="zxx" dir="ltr"><code>lt_namespace</code></bdi> and <bdi lang="zxx" dir="ltr"><code>lt_title</code></bdi>). In your existing SQL queries: *# Replace <bdi lang="zxx" dir="ltr"><code>JOIN pagelinks</code></bdi> with <bdi lang="zxx" dir="ltr"><code>JOIN linktarget</code></bdi> and <bdi lang="zxx" dir="ltr"><code>pl_</code></bdi> with <bdi lang="zxx" dir="ltr"><code>lt_</code></bdi> in the <bdi lang="zxx" dir="ltr"><code>ON</code></bdi> statement *# Below that add <bdi lang="zxx" dir="ltr"><code>JOIN pagelinks ON lt_id = pl_target_id</code></bdi> ** See <bdi lang="en" dir="ltr">[[phab:T222224]]</bdi> for technical reasoning. [https://phabricator.wikimedia.org/T222224][https://phabricator.wikimedia.org/T299947] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/20|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W20"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:58, 13 May 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26762074 --> == Tech News: 2024-21 == <section begin="technews-2024-W21"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/21|Translations]] are available. '''Recent changes''' * The [[mw:Special:MyLanguage/Extension:Nuke|Nuke]] feature, which enables administrators to mass delete pages, will now correctly delete pages which were moved to another title. [https://phabricator.wikimedia.org/T43351] * New changes have been made to the UploadWizard in Wikimedia Commons: the overall layout has been improved, by following new styling and spacing for the form and its fields; the headers and helper text for each of the fields was changed; the Caption field is now a required field, and there is an option for users to copy their caption into the media description. [https://commons.wikimedia.org/wiki/Commons:WMF_support_for_Commons/Upload_Wizard_Improvements#Changes_to_%22Describe%22_workflow][https://phabricator.wikimedia.org/T361049] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.6|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-05-21|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-05-22|en}}. It will be on all wikis from {{#time:j xg|2024-05-23|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The HTML used to render all headings [[mw:Heading_HTML_changes|is being changed to improve accessibility]]. It will change on 22 May in some skins (Timeless, Modern, CologneBlue, Nostalgia, and Monobook). Please test gadgets on your wiki on these skins and [[phab:T13555|report any related problems]] so that they can be resolved before this change is made in all other skins. The developers are also considering the introduction of a [[phab:T337286|Gadget API for adding buttons to section titles]] if that would be helpful to tool creators, and would appreciate any input you have on that. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/21|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W21"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:04, 20 May 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26786311 --> == Tech News: 2024-22 == <section begin="technews-2024-W22"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/22|Translations]] are available. '''Recent changes''' * Several bugs related to the latest updates to the UploadWizard on Wikimedia Commons have been fixed. For more information, see [[:phab:T365107|T365107]] and [[:phab:T365119|T365119]]. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] In March 2024 a new [[mw:ResourceLoader/Core_modules#addPortlet|addPortlet]] API was added to allow gadgets to create new portlets (menus) in the skin. In certain skins this can be used to create dropdowns. Gadget developers are invited to try it and [[phab:T361661|give feedback]]. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Some CSS in the Minerva skin has been removed to enable easier community configuration. Interface editors should check the rendering on mobile devices for aspects related to the classes: <bdi lang="zxx" dir="ltr"><code>.collapsible</code></bdi>{{int:comma-separator/en}}<bdi lang="zxx" dir="ltr"><code>.multicol</code></bdi>{{int:comma-separator/en}}<bdi lang="zxx" dir="ltr"><code>.reflist</code></bdi>{{int:comma-separator/en}}<bdi lang="zxx" dir="ltr"><code>.coordinates</code></bdi>{{int:comma-separator/en}}<bdi lang="zxx" dir="ltr"><code>.topicon</code></bdi>. [[phab:T361659|Further details are available on replacement CSS]] if it is needed. '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.7|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-05-28|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-05-29|en}}. It will be on all wikis from {{#time:j xg|2024-05-30|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * When you visit a wiki where you don't yet have a local account, local rules such as edit filters can sometimes prevent your account from being created. Starting this week, MediaWiki takes your global rights into account when evaluating whether you can override such local rules. [https://phabricator.wikimedia.org/T316303] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/22|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W22"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:15, 28 May 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26832205 --> == Tech News: 2024-23 == <section begin="technews-2024-W23"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/23|Translations]] are available. '''Recent changes''' * It is now possible for local administrators to add new links to the bottom of the site Tools menu without JavaScript. [[mw:Manual:Interface/Sidebar#Add or remove toolbox sections|Documentation is available]]. [https://phabricator.wikimedia.org/T6086] * The message name for the definition of the tracking category of WikiHiero has changed from "<bdi lang="zxx" dir="ltr"><code>MediaWiki:Wikhiero-usage-tracking-category</code></bdi>" to "<bdi lang="zxx" dir="ltr"><code>MediaWiki:Wikihiero-usage-tracking-category</code></bdi>". [https://gerrit.wikimedia.org/r/c/mediawiki/extensions/wikihiero/+/1035855] * One new wiki has been created: a {{int:project-localized-name-group-wikipedia}} in [[d:Q5317225|Kadazandusun]] ([[w:dtp:|<code>w:dtp:</code>]]) [https://phabricator.wikimedia.org/T365220] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.8|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-06-04|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-06-05|en}}. It will be on all wikis from {{#time:j xg|2024-06-06|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Future changes''' * Next week, on wikis with the Vector 2022 skin as the default, logged-out desktop users will be able to choose between different font sizes. The default font size will also be increased for them. This is to make Wikimedia projects easier to read. [[mw:Special:MyLanguage/Reading/Web/Accessibility for reading/Updates/2024-06 deployments|Learn more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/23|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W23"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:35, 3 June 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26844397 --> == Tech News: 2024-24 == <section begin="technews-2024-W24"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/24|Translations]] are available. '''Recent changes''' * The software used to render SVG files has been updated to a new version, fixing many longstanding bugs in SVG rendering. [https://phabricator.wikimedia.org/T265549] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The HTML used to render all headings [[mw:Heading HTML changes|is being changed to improve accessibility]]. It was changed last week in some skins (Vector legacy and Minerva). Please test gadgets on your wiki on these skins and [[phab:T13555|report any related problems]] so that they can be resolved before this change is made in Vector-2022. The developers are still considering the introduction of a [[phab:T337286|Gadget API for adding buttons to section titles]] if that would be helpful to tool creators, and would appreciate any input you have on that. * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The HTML markup used for citations by [[mw:Special:MyLanguage/Parsoid|Parsoid]] changed last week. In places where Parsoid previously added the <bdi lang="zxx" dir="ltr"><code>mw-reference-text</code></bdi> class, Parsoid now also adds the <bdi lang="zxx" dir="ltr"><code>reference-text</code></bdi> class for better compatibility with the legacy parser. [[mw:Specs/HTML/2.8.0/Extensions/Cite/Announcement|More details are available]]. [https://gerrit.wikimedia.org/r/1036705] '''Problems''' * There was a bug with the Content Translation interface that caused the tools menus to appear in the wrong location. This has now been fixed. [https://phabricator.wikimedia.org/T366374] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.9|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-06-11|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-06-12|en}}. It will be on all wikis from {{#time:j xg|2024-06-13|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The new version of MediaWiki includes another change to the HTML markup used for citations: [[mw:Special:MyLanguage/Parsoid|Parsoid]] will now generate a <bdi lang="zxx" dir="ltr"><code><nowiki><span class="mw-cite-backlink"></nowiki></code></bdi> wrapper for both named and unnamed references for better compatibility with the legacy parser. Interface administrators should verify that gadgets that interact with citations are compatible with the new markup. [[mw:Specs/HTML/2.8.0/Extensions/Cite/Announcement|More details are available]]. [https://gerrit.wikimedia.org/r/1035809] * On multilingual wikis that use the <bdi lang="zxx" dir="ltr"><code><nowiki><translate></nowiki></code></bdi> system, there is a feature that shows potentially-outdated translations with a pink background until they are updated or confirmed. From this week, confirming translations will be logged, and there is a new user-right that can be required for confirming translations if the community [[m:Special:MyLanguage/Requesting wiki configuration changes|requests it]]. [https://phabricator.wikimedia.org/T49177] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/24|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W24"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:20, 10 June 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26893898 --> == Tech News: 2024-25 == <section begin="technews-2024-W25"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/25|Translations]] are available. '''Recent changes''' * People who attempt to add an external link in the visual editor will now receive immediate feedback if they attempt to link to a domain that a project has decided to block. Please see [[mw:Special:MyLanguage/Edit_check#11_June_2024|Edit check]] for more details. [https://phabricator.wikimedia.org/T366751] * The new [[mw:Special:MyLanguage/Extension:CommunityConfiguration|Community Configuration extension]] is available [[testwiki:Special:CommunityConfiguration|on Test Wikipedia]]. This extension allows communities to customize specific features to meet their local needs. Currently only Growth features are configurable, but the extension will support other [[mw:Special:MyLanguage/Community_configuration#Use_cases|Community Configuration use cases]] in the future. [https://phabricator.wikimedia.org/T323811][https://phabricator.wikimedia.org/T360954] * The dark mode [[Special:Preferences#mw-prefsection-betafeatures|beta feature]] is now available on category and help pages, as well as more special pages. There may be contrast issues. Please report bugs on the [[mw:Talk:Reading/Web/Accessibility_for_reading|project talk page]]. [https://phabricator.wikimedia.org/T366370] '''Problems''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] Cloud Services tools were not available for 25 minutes last week. This was caused by a faulty hardware cable in the data center. [https://wikitech.wikimedia.org/wiki/Incidents/2024-06-11_WMCS_Ceph] * Last week, styling updates were made to the Vector 2022 skin. This caused unforeseen issues with templates, hatnotes, and images. Changes to templates and hatnotes were reverted. Most issues with images were fixed. If you still see any, [[phab:T367463|report them here]]. [https://phabricator.wikimedia.org/T367480] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.10|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-06-18|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-06-19|en}}. It will be on all wikis from {{#time:j xg|2024-06-20|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * Starting June 18, the [[mw:Special:MyLanguage/Help:Edit check#ref|Reference Edit Check]] will be deployed to [[phab:T361843|a new set of Wikipedias]]. This feature is intended to help newcomers and to assist edit-patrollers by inviting people who are adding new content to a Wikipedia article to add a citation when they do not do so themselves. During [[mw:Special:MyLanguage/Edit_check#Reference_Check_A/B_Test|a test at 11 wikis]], the number of citations added [https://diff.wikimedia.org/?p=127553 more than doubled] when Reference Check was shown to people. Reference Check is [[mw:Special:MyLanguage/Edit check/Configuration|community configurable]]. [https://phabricator.wikimedia.org/T361843]<!-- NOTE: THE DIFF BLOG WILL BE PUBLISHED ON MONDAY --> * [[m:Special:MyLanguage/Mailing_lists|Mailing lists]] will be unavailable for roughly two hours on Tuesday 10:00–12:00 UTC. This is to enable migration to a new server and upgrade its software. [https://phabricator.wikimedia.org/T367521] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/25|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W25"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:48, 17 June 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26911987 --> == Tech News: 2024-26 == <section begin="technews-2024-W26"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/26|Translations]] are available. '''Recent changes''' * Editors will notice that there have been some changes to the background color of text in the diff view, and the color of the byte-change numbers, last week. These changes are intended to make text more readable in both light mode and dark mode, and are part of a larger effort to increase accessibility. You can share your comments or questions [[mw:Talk:Reading/Web/Accessibility for reading|on the project talkpage]]. [https://phabricator.wikimedia.org/T361717] * The text colors that are used for visited-links, hovered-links, and active-links, were also slightly changed last week to improve their accessibility in both light mode and dark mode. [https://phabricator.wikimedia.org/T366515] '''Problems''' * You can [[mw:Special:MyLanguage/Help:DiscussionTools#Talk pages permalinking|copy permanent links to talk page comments]] by clicking on a comment's timestamp. [[mw:Talk pages project/Permalinks|This feature]] did not always work when the topic title was very long and the link was used as a wikitext link. This has been fixed. Thanks to Lofhi for submitting the bug. [https://phabricator.wikimedia.org/T356196] '''Changes later this week''' * [[File:Octicons-sync.svg|12px|link=|alt=|Recurrent item]] The [[mw:MediaWiki 1.43/wmf.11|new version]] of MediaWiki will be on test wikis and MediaWiki.org from {{#time:j xg|2024-06-25|en}}. It will be on non-Wikipedia wikis and some Wikipedias from {{#time:j xg|2024-06-26|en}}. It will be on all wikis from {{#time:j xg|2024-06-27|en}} ([[mw:MediaWiki 1.43/Roadmap|calendar]]). [https://wikitech.wikimedia.org/wiki/Deployments/Train][https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] * Starting 26 June, all talk pages messages' timestamps will become a link at English Wikipedia, making this feature available for you to use at all wikis. This link is a permanent link to the comment. It allows users to find the comment they were linked to, even if this comment has since been moved elsewhere. You can read more about this feature [[DiffBlog:/2024/01/29/talk-page-permalinks-dont-lose-your-threads/|on Diff]] or [[mw:Special:MyLanguage/Help:DiscussionTools#Talk pages permalinking|on Mediawiki.org]]. [https://phabricator.wikimedia.org/T365974] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/26|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W26"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:32, 24 June 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=26989424 --> == Tech News: 2024-27 == <section begin="technews-2024-W27"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/27|Translations]] are available. '''Recent changes''' * Over the next three weeks, dark mode will become available for all users, both logged-in and logged-out, starting with the mobile web version. This fulfils one of the [[m:Special:MyLanguage/Community_Wishlist_Survey_2023/Reading/Dark_mode|top-requested community wishes]], and improves low-contrast reading and usage in low-light settings. As part of these changes, dark mode will also work on User-pages and Portals. There is more information in [[mw:Special:MyLanguage/Reading/Web/Accessibility_for_reading/Updates#June_2024:_Typography_and_dark_mode_deployments,_new_global_preferences|the latest Web team update]]. [https://phabricator.wikimedia.org/T366364] * Logged-in users can now set [[m:Special:GlobalPreferences#mw-prefsection-rendering-skin-skin-prefs|global preferences for the text-size and dark-mode]], thanks to a combined effort across Foundation teams. This allows Wikimedians using multiple wikis to set up a consistent reading experience easily, for example by switching between light and dark mode only once for all wikis. [https://phabricator.wikimedia.org/T341278] * If you use a very old web browser some features might not work on the Wikimedia wikis. This affects Internet Explorer 11 and versions of Chrome, Firefox and Safari older than 2016. This change makes it possible to use new [[d:Q46441|CSS]] features and to send less code to all readers. [https://phabricator.wikimedia.org/T288287][https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:How_to_make_a_MediaWiki_skin#Using_CSS_variables_for_supporting_different_themes_e.g._dark_mode] * Wikipedia Admins can customize local wiki configuration options easily using [[mw:Special:MyLanguage/Community Configuration|Community Configuration]]. Community Configuration was created to allow communities to customize how some features work, because each language wiki has unique needs. At the moment, admins can configure [[mw:Special:MyLanguage/Growth/Feature_summary|Growth features]] on their home wikis, in order to better recruit and retain new editors. More options will be provided in the coming months. [https://phabricator.wikimedia.org/T366458] * Editors interested in language issues that are related to [[w:en:Unicode|Unicode standards]], can now discuss those topics at [[mw:Talk:WMF membership with Unicode Consortium|a new conversation space in MediaWiki.org]]. The Wikimedia Foundation is now a [[mw:Special:MyLanguage/WMF membership with Unicode Consortium|member of the Unicode Consortium]], and the coordination group can collaboratively review the issues discussed and, where appropriate, bring them to the attention of the Unicode Consortium. * One new wiki has been created: a {{int:project-localized-name-group-wikipedia}} in [[d:Q2891049|Mandailing]] ([[w:btm:|<code>w:btm:</code>]]) [https://phabricator.wikimedia.org/T368038] '''Problems''' * Editors can once again click on links within the visual editor's citation-preview, thanks to a bug fix by the Editing Team. [https://phabricator.wikimedia.org/T368119] '''Future changes''' * Please [https://wikimediafoundation.limesurvey.net/758713?lang=en help us to improve Tech News by taking this short survey]. The goal is to better meet the needs of the various types of people who read Tech News. The survey will be open for 2 weeks. The survey is covered by [https://foundation.wikimedia.org/wiki/Legal:Tech_News_Survey_2024_Privacy_Statement this privacy statement]. Some translations are available. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/27|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W27"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:59, 1 July 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27038456 --> == Tech News: 2024-28 == <section begin="technews-2024-W28"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/28|Translations]] are available. '''Recent changes''' * At the Wikimedia Foundation a new task force was formed to replace the disabled Graph with [[mw:Special:MyLanguage/Extension:Chart/Project|more secure, easy to use, and extensible Chart]]. You can [[mw:Special:MyLanguage/Newsletter:Chart Project|subscribe to the newsletter]] to get notified about new project updates and other news about Chart. * The [[m:Special:MyLanguage/CampaignEvents|CampaignEvents]] extension is now available on Meta-wiki, Igbo Wikipedia, and Swahili Wikipedia, and can be requested on your wiki. This extension helps in managing and making events more visible, giving Event organizers the ability to use tools like the Event registration tool. To learn more about the deployment status and how to request this extension for your wiki, visit the [[m:Special:MyLanguage/CampaignEvents/Deployment_status|CampaignEvents page on Meta-wiki]]. * Editors using the iOS Wikipedia app who have more than 50 edits can now use the [[mw:Special:MyLanguage/Wikimedia Apps/iOS Suggested edits#Add an image|Add an Image]] feature. This feature presents opportunities for small but useful contributions to Wikipedia. * Thank you to [[mw:MediaWiki Product Insights/Contributor retention and growth/Celebration|all of the authors]] who have contributed to MediaWiki Core. As a result of these contributions, the [[mw:MediaWiki Product Insights/Contributor retention and growth|percentage of authors contributing more than 5 patches has increased by 25% since last year]], which helps ensure the sustainability of the platform for the Wikimedia projects. '''Problems''' * A problem with the color of the talkpage tabs always showing as blue, even for non-existent pages which should have been red, affecting the Vector 2022 skin, [[phab:T367982|has been fixed]]. '''Future changes''' * The Trust and Safety Product team wants to introduce [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] with as little disruption to tools and workflows as possible. Volunteer developers, including gadget and user-script maintainers, are kindly asked to update the code of their tools and features to handle temporary accounts. The team has [[mw:Trust and Safety Product/Temporary Accounts/For developers|created documentation]] explaining how to do the update. [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/For developers/2024-04 CTA|Learn more]]. '''Tech News survey''' * Please [https://wikimediafoundation.limesurvey.net/758713?lang=en help us to improve Tech News by taking this short survey]. The goal is to better meet the needs of the various types of people who read Tech News. The survey will be open for 1 more week. The survey is covered by [https://foundation.wikimedia.org/wiki/Legal:Tech_News_Survey_2024_Privacy_Statement this privacy statement]. Some translations are available. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/28|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W28"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:31, 8 July 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27080357 --> == Tech News: 2024-29 == <section begin="technews-2024-W29"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/29|Translations]] are available. '''Tech News survey''' * Please [https://wikimediafoundation.limesurvey.net/758713?lang=en help us to improve Tech News by taking this short survey]. The goal is to better meet the needs of the various types of people who read Tech News. The survey will be open for 3 more days. The survey is covered by [https://foundation.wikimedia.org/wiki/Legal:Tech_News_Survey_2024_Privacy_Statement this privacy statement]. Some translations are available. '''Recent changes''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Wikimedia developers can now officially continue to use both [[mw:Special:MyLanguage/Gerrit|Gerrit]] and [[mw:Special:MyLanguage/GitLab|GitLab]], due to a June 24 decision by the Wikimedia Foundation to support software development on both platforms. Gerrit and GitLab are both code repositories used by developers to write, review, and deploy the software code that supports the MediaWiki software that the wiki projects are built on, as well as the tools used by editors to create and improve content. This decision will safeguard the productivity of our developers and prevent problems in code review from affecting our users. More details are available in the [[mw:GitLab/Migration status|Migration status]] page. * The Wikimedia Foundation seeks applicants for the [[m:Special:MyLanguage/Product and Technology Advisory Council/Proposal|Product and Technology Advisory Council]] (PTAC). This group will bring technical contributors and Wikimedia Foundation together to co-define a more resilient, future-proof technological platform. Council members will evaluate and consult on the movement's product and technical activities, so that we develop multi-generational projects. We are looking for a range of technical contributors across the globe, from a variety of Wikimedia projects. [[m:Special:MyLanguage/Product and Technology Advisory Council/Proposal#Joining the PTAC as a technical volunteer|Please apply here by August 10]]. * Editors with rollback user-rights who use the Wikipedia App for Android can use the new [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/Anti Vandalism|Edit Patrol]] features. These features include a new feed of Recent Changes, related links such as Undo and Rollback, and the ability to create and save a personal library of user talk messages to use while patrolling. If your wiki wants to make these features available to users who do not have rollback rights but have reached a certain edit threshold, [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android#Contact us|you can contact the team]]. You can [[diffblog:2024/07/10/ِaddressing-vandalism-with-a-tap-the-journey-of-introducing-the-patrolling-feature-in-the-mobile-app/|read more about this project on Diff blog]]. * Editors who have access to [[m:Special:MyLanguage/The_Wikipedia_Library|The Wikipedia Library]] can once again use non-open access content in SpringerLinks, after the Foundation [[phab:T368865|contacted]] them to restore access. You can read more about [[m:Tech/News/Recently_resolved_community_tasks|this and 21 other community-submitted tasks that were completed last week]]. '''Changes later this week''' * This week, [[mw:Special:MyLanguage/Reading/Web/Accessibility for reading/Updates/2024-07 deployments|dark mode will be available on a number of Wikipedias]], both desktop and mobile, for logged-in and logged-out users. Interface admins and user script maintainers are encouraged to check gadgets and user scripts in the dark mode, to find any hard-coded colors and fix them. There are some [[mw:Special:MyLanguage/Recommendations for night mode compatibility on Wikimedia wikis|recommendations for dark mode compatibility]] to help. '''Future changes''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Next week, functionaries, volunteers maintaining tools, and software development teams are invited to test the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] feature on testwiki. Temporary accounts is a feature that will help improve privacy on the wikis. No further temporary account deployments are scheduled yet. Please [[mw:Talk:Trust and Safety Product/Temporary Accounts|share your opinions and questions on the project talk page]]. [https://phabricator.wikimedia.org/T348895] * Editors who upload files cross-wiki, or teach other people how to do so, may wish to join a Wikimedia Commons discussion. The Commons community is discussing limiting who can upload files through the cross-wiki upload/Upload dialog feature to users auto-confirmed on Wikimedia Commons. This is due to the large amount of copyright violations uploaded this way. There is a short summary at [[c:Special:MyLanguage/Commons:Cross-wiki upload|Commons:Cross-wiki upload]] and [[c:Commons:Village pump/Proposals#Deactivate cross-wiki uploads for new users|discussion at Commons:Village Pump]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/29|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' You can also get other news from the [[m:Special:MyLanguage/Wikimedia Foundation Bulletin|Wikimedia Foundation Bulletin]]. </div><section end="technews-2024-W29"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:31, 16 July 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27124561 --> == Tech News: 2024-30 == <section begin="technews-2024-W30"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/30|Translations]] are available. '''Feature News''' * Stewards can now [[:m:Special:MyLanguage/Global_blocks|globally block]] accounts. Before [[phab:T17294|the change]] only IP addresses and IP ranges could be blocked globally. Global account blocks are useful when the blocked user should not be logged out. [[:m:Special:MyLanguage/Global_locks|Global locks]] (a similar tool logging the user out of their account) are unaffected by this change. The new global account block feature is related to the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|Temporary Accounts]] project, which is a new type of user account that replaces IP addresses of unregistered editors that are no longer made public. * Later this week, Wikimedia site users will notice that the Interface of [[mw:Special:MyLanguage/Extension:FlaggedRevs|FlaggedRevs]] (also known as "Pending Changes") is improved and consistent with the rest of the MediaWiki interface and [[mw:Special:MyLanguage/Codex|Wikimedia's design system]]. The FlaggedRevs interface experience on mobile and [[mw:Special:MyLanguage/Skin:MinervaNeue|Minerva skin]] was inconsistent before it was fixed and ported to [[mw:Special:MyLanguage/Codex|Codex]] by the WMF Growth team and some volunteers. [https://phabricator.wikimedia.org/T191156] * Wikimedia site users can now submit account vanishing requests via [[m:Special:GlobalVanishRequest|GlobalVanishRequest]]. This feature is used when a contributor wishes to stop editing forever. It helps you hide your past association and edit to protect your privacy. Once processed, the account will be locked and renamed. [https://phabricator.wikimedia.org/T367329] * Have you tried monitoring and addressing vandalism in Wikipedia using your phone? [https://diff.wikimedia.org/2024/07/10/%d9%90addressing-vandalism-with-a-tap-the-journey-of-introducing-the-patrolling-feature-in-the-mobile-app/ A Diff blog post on Patrolling features in the Mobile App] highlights some of the new capabilities of the feature, including swiping through a feed of recent changes and a personal library of user talk messages for use when patrolling from your phone. * Wikimedia contributors and GLAM (galleries, libraries, archives, and museums) organisations can now learn and measure the impact Wikimedia Commons is having towards creating quality encyclopedic content using the [https://doc.wikimedia.org/generated-data-platform/aqs/analytics-api/reference/commons.html Commons Impact Metrics] analytics dashboard. The dashboard offers organizations analytics on things like monthly edits in a category, the most viewed files, and which Wikimedia articles are using Commons images. As a result of these new data dumps, GLAM organisation can more reliably measure their return on investment for programs bringing content into the digital Commons. [https://diff.wikimedia.org/2024/07/19/commons-impact-metrics-now-available-via-data-dumps-and-api/] '''Project Updates''' * Come share your ideas for improving the wikis on the newly reopened [[m:Special:MyLanguage/Community Wishlist|Community Wishlist]]. The Community Wishlist is Wikimedia’s forum for volunteers to share ideas (called wishes) to improve how the wikis work. The new version of the wishlist is always open, works with both wikitext and Visual Editor, and allows wishes in any language. '''Learn more''' * Have you ever wondered how Wikimedia software works across over 300 languages? This is 253 languages more than the Google Chrome interface, and it's no accident. The Language and Product Localization Team at the Wikimedia Foundation supports your work by adapting all the tools and interfaces in the MediaWiki software so that contributors in our movement who translate pages and strings can translate them and have the sites in all languages. Read more about the team and their upcoming work on [https://diff.wikimedia.org/2024/07/17/building-towards-a-robust-multilingual-knowledge-ecosystem-for-the-wikimedia-movement/ Diff]. * How can Wikimedia build innovative and experimental products while maintaining such heavily used websites? A recent [https://diff.wikimedia.org/2024/07/09/on-the-value-of-experimentation/ blog post] by WMF staff Johan Jönsson highlights the work of the [[m:Future Audiences#Objectives and Key Results|WMF Future Audience initiative]], where the goal is not to build polished products but test out new ideas, such as a [[m:Future_Audiences/Experiments: conversational/generative AI|ChatGPT plugin]] and [[m:Future_Audiences/Experiment:Add a Fact|Add a Fact]], to help take Wikimedia into the future. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/30|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' You can also get other news from the [[m:Special:MyLanguage/Wikimedia Foundation Bulletin|Wikimedia Foundation Bulletin]]. </div><section end="technews-2024-W30"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:04, 23 July 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27142915 --> == Tech News: 2024-31 == <section begin="technews-2024-W31"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/31|Translations]] are available. '''Feature news''' * Editors using the Visual Editor in languages that use non-Latin characters for numbers, such as Hindi, Manipuri and Eastern Arabic, may notice some changes in the formatting of reference numbers. This is a side effect of preparing a new sub-referencing feature, and will also allow fixing some general numbering issues in Visual Editor. If you notice any related problems on your wiki, please share details at the [[m:Talk:WMDE Technical Wishes/Sub-referencing|project talkpage]]. '''Bugs status''' * Some logged-in editors were briefly unable to edit or load pages last week. [[phab:T370304|These errors]] were mainly due to the addition of new [[mw:Special:MyLanguage/Help:Extension:Linter|linter]] rules which led to caching problems. Fixes have been applied and investigations are continuing. * Editors can use the [[mw:Special:MyLanguage/Trust and Safety Product/IP Info|IP Information tool]] to get information about IP addresses. This tool is available as a Beta Feature in your preferences. The tool was not available for a few days last week, but is now working again. Thank you to Shizhao for filing the bug report. You can read about that, and [[m:Tech/News/Recently resolved community tasks#2024-07-25|28 other community-submitted tasks]] that were resolved last week. '''Project updates''' * There are new features and improvements to Phabricator from the Release Engineering and Collaboration Services teams, and some volunteers, including: the search systems, the new task creation system, the login systems, the translation setup which has resulted in support for more languages (thanks to Pppery), and fixes for many edge-case errors. You can [[phab:phame/post/view/316/iterative_improvements/|read details about these and other improvements in this summary]]. * There is an [[mw:Special:MyLanguage/Extension:Chart/Project/Updates|update on the Charts project]]. The team has decided which visualization library to use, which chart types to start focusing on, and where to store chart definitions. * One new wiki has been created: a {{int:project-localized-name-group-wikivoyage}} in [[d:Q9056|Czech]] ([[voy:cs:|<code>voy:cs:</code>]]) [https://phabricator.wikimedia.org/T370905] '''Learn more''' * There is a [[diffblog:2024/07/26/the-journey-to-open-our-first-data-center-in-south-america/|new Wikimedia Foundation data center]] in São Paulo, Brazil which helps to reduce load times. * There is new [[diffblog:2024/07/22/the-perplexing-process-of-uploading-images-to-wikipedia/|user research]] on problems with the process of uploading images. * Commons Impact Metrics are [[diffblog:2024/07/19/commons-impact-metrics-now-available-via-data-dumps-and-api/|now available]] via data dumps and API. * The latest quarterly [[mw:Technical Community Newsletter/2024/July|Technical Community Newsletter]] is now available. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W31"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:10, 29 July 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27164109 --> == Tech News: 2024-32 == <section begin="technews-2024-W32"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/32|Translations]] are available. '''Feature news''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Two new parser functions will be available this week: <code><nowiki>{{</nowiki>[[mw:Special:MyLanguage/Help:Magic_words#dir|#dir]]<nowiki>}}</nowiki></code> and <code><nowiki>{{</nowiki>[[mw:Special:MyLanguage/Help:Magic_words#bcp47|#bcp47]]<nowiki>}}</nowiki></code>. These will reduce the need for <code>Template:Dir</code> and <code>Template:BCP47</code> on Commons and allow us to [[phab:T343131|drop 100 million rows]] from the "what links here" database. Editors at any wiki that use these templates, can help by replacing the templates with these new functions. The templates at Commons will be updated during the Hackathon at Wikimania. [https://phabricator.wikimedia.org/T359761][https://phabricator.wikimedia.org/T366623] * Communities can request the activation of the visual editor on entire namespaces where discussions sometimes happen (for instance ''Wikipedia:'' or ''Wikisource:'' namespaces) if they understand the [[mw:Special:MyLanguage/Help:VisualEditor/FAQ#WPNS|known limitations]]. For discussions, users can already use [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]] in these namespaces. * The tracking category "Pages using Timeline" has been renamed to "Pages using the EasyTimeline extension" [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3ATimeline-tracking-category&namespace=8 in TranslateWiki]. Wikis that have created the category locally should rename their local creation to match. '''Project updates''' * Editors who help to organize WikiProjects and similar on-wiki collaborations, are invited to share ideas and examples of successful collaborations with the Campaigns and Programs teams. You can fill out [[m:Special:MyLanguage/Campaigns/WikiProjects|a brief survey]] or share your thoughts [[m:Talk:Campaigns/WikiProjects|on the talkpage]]. The teams are particularly looking for details about successful collaborations on non-English wikis. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] The new parser is being rolled out on {{int:project-localized-name-group-wikivoyage}} wikis over the next few months. The {{int:project-localized-name-enwikivoyage}} and {{int:project-localized-name-hewikivoyage}} were [[phab:T365367|switched]] to Parsoid last week. For more information, see [[mw:Parsoid/Parser_Unification|Parsoid/Parser Unification]]. '''Learn more''' * There will be more than 200 sessions at Wikimania this week. Here is a summary of some of the [[diffblog:2024/08/05/interested-in-product-and-tech-here-are-some-wikimania-sessions-you-dont-want-to-miss/|key sessions related to the product and technology area]]. * The latest [[m:Special:MyLanguage/Wikimedia Foundation Bulletin/2024/07-02|Wikimedia Foundation Bulletin]] is available. * The latest quarterly [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2024/July|Language and Internationalization newsletter]] is available. It includes: New design previews for Translatable pages; Updates about MinT for Wiki Readers; the release of Translation dumps; and more. * The latest quarterly [[mw:Special:MyLanguage/Growth/Newsletters/31|Growth newsletter]] is available. * The latest monthly [[mw:Special:MyLanguage/MediaWiki Product Insights/Reports/July 2024|MediaWiki Product Insights newsletter]] is available. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W32"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:43, 5 August 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27233905 --> == Tech News: 2024-33 == <section begin="technews-2024-W33"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/33|Translations]] are available. '''Feature news''' * [[mw:Special:MyLanguage/Extension:AbuseFilter|AbuseFilter]] editors and maintainers can now [[mw:Special:MyLanguage/Extension:AbuseFilter/Actions#Show a CAPTCHA|make a CAPTCHA show if a filter matches an edit]]. This allows communities to quickly respond to spamming by automated bots. [https://phabricator.wikimedia.org/T20110] * [[m:Special:MyLanguage/Stewards|Stewards]] can now specify if global blocks should prevent account creation. Before [[phab:T17273|this change]] by the [[mw:Special:MyLanguage/Trust and Safety Product|Trust and Safety Product]] Team, all global blocks would prevent account creation. This will allow stewards to reduce the unintended side-effects of global blocks on IP addresses. '''Project updates''' * [[wikitech:Help talk:Toolforge/Toolforge standards committee#August_2024_committee_nominations|Nominations are open on Wikitech]] for new members to refresh the [[wikitech:Help:Toolforge/Toolforge standards committee|Toolforge standards committee]]. The committee oversees the Toolforge [[wikitech:Help:Toolforge/Right to fork policy|Right to fork policy]] and [[wikitech:Help:Toolforge/Abandoned tool policy|Abandoned tool policy]] among other duties. Nominations will remain open until at least 2024-08-26. * One new wiki has been created: a {{int:project-localized-name-group-wikipedia}} in [[d:Q2880037|West Coast Bajau]] ([[w:bdr:|<code>w:bdr:</code>]]) [https://phabricator.wikimedia.org/T371757] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W33"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:21, 12 August 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27253654 --> == Tech News: 2024-34 == <section begin="technews-2024-W34"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/34|Translations]] are available. '''Feature news''' * Editors who want to re-use references but with different details such as page numbers, will be able to do so by the end of 2024, using a new [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#Sub-referencing in a nutshell|sub-referencing]] feature. You can read more [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|about the project]] and [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#Test|how to test the prototype]]. * Editors using tracking categories to identify which pages use specific extensions may notice that six of the categories have been renamed to make them more easily understood and consistent. These categories are automatically added to pages that use specialized MediaWiki extensions. The affected names are for: [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3Aintersection-category&namespace=8 DynamicPageList], [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3Akartographer-tracking-category&namespace=8 Kartographer], [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3Aphonos-tracking-category&namespace=8 Phonos], [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3Arss-tracking-category&namespace=8 RSS], [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3Ascore-use-category&namespace=8 Score], [https://translatewiki.net/wiki/Special:Translations?message=MediaWiki%3Awikihiero-usage-tracking-category&namespace=8 WikiHiero]. Wikis that have created the category locally should rename their local creation to match. Thanks to Pppery for these improvements. [https://phabricator.wikimedia.org/T347324] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Technical volunteers who edit modules and want to get a list of the categories used on a page, can now do so using the <code><bdi lang="zxx" dir="ltr">categories</bdi></code> property of <code><bdi lang="zxx" dir="ltr">[[mediawikiwiki:Special:MyLanguage/Extension:Scribunto/Lua reference manual#Title objects|mw.title objects]]</bdi></code>. This enables wikis to configure workflows such as category-specific edit notices. Thanks to SD001 for these improvements. [https://phabricator.wikimedia.org/T50175][https://phabricator.wikimedia.org/T85372] '''Bugs status''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Your help is needed to check if any pages need to be moved or deleted. A maintenance script was run to clean up unreachable pages (due to Unicode issues or introduction of new namespaces/namespace aliases). The script tried to find appropriate names for the pages (e.g. by following the Unicode changes or by moving pages whose titles on Wikipedia start with <code>Talk:WP:</code> so that their titles start with <code>Wikipedia talk:</code>), but it may have failed for some pages, and moved them to <bdi lang="zxx" dir="ltr">[[Special:PrefixIndex/T195546/]]</bdi> instead. Your community should check if any pages are listed there, and move them to the correct titles, or delete them if they are no longer needed. A full log (including pages for which appropriate names could be found) is available in [[phab:P67388]]. * Editors who volunteer as [[mw:Special:MyLanguage/Help:Growth/Mentorship|mentors]] to newcomers on their wiki are once again able to access lists of potential mentees who they can connect with to offer help and guidance. This functionality was restored thanks to [[phab:T372164|a bug fix]]. Thank you to Mbch331 for filing the bug report. You can read about that, and 18 other community-submitted tasks that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. '''Project updates''' * The application deadline for the [[m:Special:MyLanguage/Product and Technology Advisory Council/Proposal|Product & Technology Advisory Council]] (PTAC) has been extended to September 16. Members will help by providing advice to Foundation Product and Technology leadership on short and long term plans, on complex strategic problems, and help to get feedback from more contributors and technical communities. Selected members should expect to spend roughly 5 hours per month for the Council, during the one year pilot. Please consider applying, and spread the word to volunteers you think would make a positive contribution to the committee. '''Learn more''' * The [[m:Special:MyLanguage/Coolest Tool Award#2024 Winners|2024 Coolest Tool Awards]] were awarded at Wikimania, in seven categories. For example, one award went to the ISA Tool, used for adding structured data to files on Commons, which was recently improved during the [[m:Event:Wiki Mentor Africa ISA Hackathon 2024|Wiki Mentor Africa Hackathon]]. You can see video demonstrations of each tool at the awards page. Congratulations to this year's recipients, and thank you to all tool creators and maintainers. * The latest [[m:Special:MyLanguage/Wikimedia Foundation Bulletin/2024/08-01|Wikimedia Foundation Bulletin]] is available, and includes some highlights from Wikimania, an upcoming Language community meeting, and other news from the movement. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W34"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:54, 20 August 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27307284 --> == Tech News: 2024-35 == <section begin="technews-2024-W35"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/35|Translations]] are available. '''Feature news''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Administrators can now test the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] feature on test2wiki. This was done to allow cross-wiki testing of temporary accounts, for when temporary accounts switch between projects. The feature was enabled on testwiki a few weeks ago. No further temporary account deployments are scheduled yet. Temporary Accounts is a project to create a new type of user account that replaces IP addresses of unregistered editors which are no longer made public. Please [[mw:Talk:Trust and Safety Product/Temporary Accounts|share your opinions and questions on the project talk page]]. * Later this week, editors at wikis that use [[mw:Special:MyLanguage/Extension:FlaggedRevs|FlaggedRevs]] (also known as "Pending Changes") may notice that the indicators at the top of articles have changed. This change makes the system more consistent with the rest of the MediaWiki interface. [https://phabricator.wikimedia.org/T191156] '''Bugs status''' * Editors who use the 2010 wikitext editor, and use the Character Insert buttons, will [[phab:T361465|no longer]] experience problems with the buttons adding content into the edit-summary instead of the edit-window. You can read more about that, and 26 other community-submitted tasks that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. '''Project updates''' * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] Please review and vote on [[m:Special:MyLanguage/Community Wishlist/Focus areas|Focus Areas]], which are groups of wishes that share a problem. Focus Areas were created for the newly reopened Community Wishlist, which is now open year-round for submissions. The first batch of focus areas are specific to moderator workflows, around welcoming newcomers, minimizing repetitive tasks, and prioritizing tasks. Once volunteers have reviewed and voted on focus areas, the Foundation will then review and select focus areas for prioritization. * Do you have a project and are willing to provide a three (3) month mentorship for an intern? [[mw:Special:MyLanguage/Outreachy|Outreachy]] is a twice a year program for people to participate in a paid internship that will start in December 2024 and end in early March 2025, and they need mentors and projects to work on. Projects can be focused on coding or non-coding (design, documentation, translation, research). See the Outreachy page for more details, and a list of past projects since 2013. '''Learn more''' * If you're curious about the product and technology improvements made by the Wikimedia Foundation last year, read [[diffblog:2024/08/21/wikimedia-foundation-product-technology-improving-the-user-experience/|this recent highlights summary on Diff]]. * To learn more about the technology behind the Wikimedia projects, you can now watch sessions from the technology track at Wikimania 2024 on Commons. This week, check out: ** [[c:File:Wikimania 2024 - Ohrid - Day 2 - Community Configuration - Shaping On-Wiki Functionality Together.webm|Community Configuration - Shaping On-Wiki Functionality Together]] (55 mins) - about the [[mw:Special:MyLanguage/Community Configuration|Community Configuration]] project. ** [[c:File:Wikimania 2024 - Belgrade - Day 1 - Future of MediaWiki. A sustainable platform to support a collaborative user base and billions of page views.webm|Future of MediaWiki. A sustainable platform to support a collaborative user base and billions of page views]] (30 mins) - an overview for both technical and non technical audiences, covering some of the challenges and open questions, related to the [[mw:MediaWiki Product Insights|platform evolution, stewardship and developer experiences]] research. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W35"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:33, 26 August 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27341211 --> == Tech News: 2024-36 == <section begin="technews-2024-W36"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/36|Translations]] are available. '''Weekly highlight''' * Editors and volunteer developers interested in data visualisation can now test the new software for charts. Its early version is available on beta Commons and beta Wikipedia. This is an important milestone before making charts available on regular wikis. You can [[mw:Special:MyLanguage/Extension:Chart/Project/Updates|read more about this project update]] and help to test the charts. '''Feature news''' * Editors who use the [[{{#special:Unusedtemplates}}]] page can now filter out pages which are expected to be there permanently, such as sandboxes, test-cases, and templates that are always substituted. Editors can add the new magic word [[mw:Special:MyLanguage/Help:Magic words#EXPECTUNUSEDTEMPLATE|<code dir="ltr"><nowiki>__EXPECTUNUSEDTEMPLATE__</nowiki></code>]] to a template page to hide it from the listing. Thanks to Sophivorus and DannyS712 for these improvements. [https://phabricator.wikimedia.org/T184633] * Editors who use the New Topic tool on discussion pages, will [[phab:T334163|now be reminded]] to add a section header, which should help reduce the quantity of newcomers who add sections without a header. You can read more about that, and {{formatnum:28}} other community-submitted tasks that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. * Last week, some Toolforge tools had occasional connection problems. The cause is still being investigated, but the problems have been resolved for now. [https://phabricator.wikimedia.org/T373243] * Translation administrators at multilingual wikis, when editing multiple translation units, can now easily mark which changes require updates to the translation. This is possible with the [[phab:T298852#10087288|new dropdown menu]]. '''Project updates''' * A new draft text of a policy discussing the use of Wikimedia's APIs [[m:Special:MyLanguage/API Policy Update 2024|has been published on Meta-Wiki]]. The draft text does not reflect a change in policy around the APIs; instead, it is an attempt to codify existing API rules. Comments, questions, and suggestions are welcome on [[m:Talk:API Policy Update 2024|the proposed update’s talk page]] until September 13 or until those discussions have concluded. '''Learn more''' * To learn more about the technology behind the Wikimedia projects, you can now watch sessions from the technology track at Wikimania 2024 on Commons. This week, check out: ** [[c:File:Wikimania 2024 - Ohrid - Day 2 - Charts, the successor of Graphs - A secure and extensible tool for data visualization.webm|Charts, the successor of Graphs - A secure and extensible tool for data visualization]] (25 mins) – about the above-mentioned Charts project. ** [[c:File:Wikimania 2024 - Ohrid - Day 3 - State of Language Technology and Onboarding at Wikimedia.webm|State of Language Technology and Onboarding at Wikimedia]] (90 mins) – about some of the language tools that support Wikimedia sites, such as [[mw:Special:MyLanguage/Content translation|Content]]/[[mw:Special:MyLanguage/Content translation/Section translation|Section Translation]], [[mw:Special:MyLanguage/MinT|MinT]], and LanguageConverter; also the current state and future of languages onboarding. [https://phabricator.wikimedia.org/T368772] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W36"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:07, 3 September 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27390268 --> == Tech News: 2024-37 == <section begin="technews-2024-W37"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/37|Translations]] are available. '''Feature news''' * Starting this week, the standard [[mw:Special:MyLanguage/Extension:CodeMirror|syntax highlighter]] will receive new colors that make them compatible in dark mode. This is the first of many changes to come as part of a major upgrade to syntax highlighting. You can learn more about what's to come on the [[mw:Special:MyLanguage/Help:Extension:CodeMirror|help page]]. [https://phabricator.wikimedia.org/T365311][https://phabricator.wikimedia.org/T259059] * Editors of wikis using Wikidata will now be notified of only relevant Wikidata changes in their watchlist. This is because the Lua functions <bdi lang="zxx" dir="ltr"><code>entity:getSitelink()</code></bdi> and <bdi lang="zxx" dir="ltr"><code>mw.wikibase.getSitelink(qid)</code></bdi> will have their logic unified for tracking different aspects of sitelinks to reduce junk notifications from [[m:Wikidata For Wikimedia Projects/Projects/Watchlist Wikidata Sitelinks Tracking|inconsistent sitelinks tracking]]. [https://phabricator.wikimedia.org/T295356] '''Project updates''' * Users of all Wikis will have access to Wikimedia sites as read-only for a few minutes on September 25, starting at 15:00 UTC. This is a planned datacenter switchover for maintenance purposes. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T370962] * Contributors of [[phab:T363538#10123348|11 Wikipedias]], including English will have a new <bdi lang="zxx" dir="ltr"><code>MOS</code></bdi> namespace added to their Wikipedias. This improvement ensures that links beginning with <bdi lang="zxx" dir="ltr"><code>MOS:</code></bdi> (usually shortcuts to the [[w:en:Wikipedia:Manual of Style|Manual of Style]]) are not broken by [[w:en:Mooré|Mooré]] Wikipedia (language code <bdi lang="zxx" dir="ltr"><code>mos</code></bdi>). [https://phabricator.wikimedia.org/T363538] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W37"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:52, 9 September 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27424457 --> == Tech News: 2024-38 == <section begin="technews-2024-W38"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/38|Translations]] are available. '''Improvements and Maintenance''' * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] Editors interested in templates can help by reading the latest Wishlist focus area, [[m:Special:MyLanguage/Community Wishlist/Focus areas/Template recall and discovery|Template recall and discovery]], and share your feedback on the talkpage. This input helps the Community Tech team to decide the right technical approach to build. Everyone is also encouraged to continue adding [[m:Special:MyLanguage/Community Wishlist|new wishes]]. * The new automated [[{{#special:NamespaceInfo}}]] page helps editors understand which [[mw:Special:MyLanguage/Help:Namespaces|namespaces]] exist on each wiki, and some details about how they are configured. Thanks to DannyS712 for these improvements. [https://phabricator.wikimedia.org/T263513] * [[mw:Special:MyLanguage/Help:Edit check#Reference check|References Check]] is a feature that encourages editors to add a citation when they add a new paragraph to a Wikipedia article. For a short time, the corresponding tag "Edit Check (references) activated" was erroneously being applied to some edits outside of the main namespace. This has been fixed. [https://phabricator.wikimedia.org/T373692] * It is now possible for a wiki community to change the order in which a page’s categories are displayed on their wiki. By default, categories are displayed in the order they appear in the wikitext. Now, wikis with a consensus to do so can [[m:Special:MyLanguage/Requesting wiki configuration changes|request]] a configuration change to display them in alphabetical order. [https://phabricator.wikimedia.org/T373480] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Tool authors can now access ToolsDB's [[wikitech:Portal:Data Services#ToolsDB|public databases]] from both [[m:Special:MyLanguage/Research:Quarry|Quarry]] and [[wikitech:Superset|Superset]]. Those databases have always been accessible to every [[wikitech:Portal:Toolforge|Toolforge]] user, but they are now more broadly accessible, as Quarry can be accessed by anyone with a Wikimedia account. In addition, Quarry's internal database can now be [[m:Special:MyLanguage/Research:Quarry#Querying Quarry's own database|queried from Quarry itself]]. This database contains information about all queries that are being run and starred by users in Quarry. This information was already public through the web interface, but you can now query it using SQL. You can read more about that, and {{formatnum:20}} other community-submitted tasks that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. * Any pages or tools that still use the very old CSS classes <bdi lang="zxx" dir="ltr"><code>mw-message-box</code></bdi> need to be updated. These old classes will be removed next week or soon afterwards. Editors can use a [https://global-search.toolforge.org/?q=mw-message-box&regex=1&namespaces=&title= global-search] to determine what needs to be changed. It is possible to use the newer <bdi lang="zxx" dir="ltr"><code>cdx-message</code></bdi> group of classes as a replacement (see [https://doc.wikimedia.org/codex/latest/components/demos/message.html#css-only-version the relevant Codex documentation], and [https://meta.wikimedia.org/w/index.php?title=Tech/Header&diff=prev&oldid=27449042 an example update]), but using locally defined onwiki classes would be best. [https://phabricator.wikimedia.org/T374499] '''Technical project updates''' * Next week, all Wikimedia wikis will be read-only for a few minutes. This will start on September 25 at [https://zonestamp.toolforge.org/1727276400 15:00 UTC]. This is a planned datacenter switchover for maintenance purposes. [[m:Special:MyLanguage/Tech/Server switch|This maintenance process also targets other services.]] The previous switchover took 3 minutes, and the Site Reliability Engineering teams use many tools to make sure that this essential maintenance work happens as quickly as possible. [https://phabricator.wikimedia.org/T370962] '''Tech in depth''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] The latest monthly [[mw:Special:MyLanguage/MediaWiki Product Insights/Reports/August 2024|MediaWiki Product Insights newsletter]] is available. This edition includes details about: research about [[mw:Special:MyLanguage/Manual:Hooks|hook]] handlers to help simplify development, research about performance improvements, work to improve the REST API for end-users, and more. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] To learn more about the technology behind the Wikimedia projects, you can now watch sessions from the technology track at Wikimania 2024 on Commons. This week, check out: ** [[c:File:Wikimania 2024 - Auditorium Kyiv - Day 4 - Hackathon Showcase.webm|Hackathon Showcase]] (45 mins) - 19 short presentations by some of the Hackathon participants, describing some of the projects they worked on, such as automated testing of maintenance scripts, a video-cutting command line tool, and interface improvements for various tools. There are [[phab:T369234|more details and links available]] in the Phabricator task. ** [[c:File:Co-Creating a Sustainable Future for the Toolforge Ecosystem.webm|Co-Creating a Sustainable Future for the Toolforge Ecosystem]] (40 mins) - a roundtable discussion for tool-maintainers, users, and supporters of Toolforge about how to make the platform sustainable and how to evaluate the tools available there. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W38"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:02, 17 September 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27460876 --> == Tech News: 2024-39 == <section begin="technews-2024-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/39|Translations]] are available. '''Weekly highlight''' * All wikis will be [[m:Special:MyLanguage/Tech/Server switch|read-only]] for a few minutes on Wednesday September 25 at [https://zonestamp.toolforge.org/1727276400 15:00 UTC]. Reading the wikis will not be interrupted, but editing will be paused. These twice-yearly processes allow WMF's site reliability engineering teams to remain prepared to keep the wikis functioning even in the event of a major interruption to one of our data centers. '''Updates for editors''' [[File:Add alt text from a halfsheet, with the article behind.png|thumb|A screenshot of the interface for the Alt Text suggested-edit feature]] * Editors who use the iOS Wikipedia app in Spanish, Portuguese, French, or Chinese, may see the [[mw:Special:MyLanguage/Wikimedia Apps/iOS Suggested edits project/Alt Text Experiment|Alt Text suggested-edit experiment]] after editing an article, or completing a suggested edit using "[[mw:Special:MyLanguage/Wikimedia Apps/iOS Suggested edits project#Hypothesis 2 Add an Image Suggested Edit|Add an image]]". Alt-text helps people with visual impairments to read Wikipedia articles. The team aims to learn if adding alt-text to images is a task that editors can be successful with. Please share any feedback on [[mw:Talk:Wikimedia Apps/iOS Suggested edits project/Alt Text Experiment|the discussion page]]. * The Codex color palette has been updated with new and revised colors for the MediaWiki user interfaces. The [[mw:Special:MyLanguage/Design System Team/Color/Design documentation#Updates|most noticeable changes]] for editors include updates for: dark mode colors for Links and for quiet Buttons (progressive and destructive), visited Link colors for both light and dark modes, and background colors for system-messages in both light and dark modes. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] It is now possible to include clickable wikilinks and external links inside code blocks. This includes links that are used within <code><nowiki><syntaxhighlight></nowiki></code> tags and on code pages (JavaScript, CSS, Scribunto and Sanitized CSS). Uses of template syntax <code><nowiki>{{…}}</nowiki></code> are also linked to the template page. Thanks to SD0001 for these improvements. [https://phabricator.wikimedia.org/T368166] * Two bugs were fixed in the [[m:Special:MyLanguage/Account vanishing|GlobalVanishRequest]] system by improving the logging and by removing an incorrect placeholder message. [https://phabricator.wikimedia.org/T370595][https://phabricator.wikimedia.org/T372223] * View all {{formatnum:25}} community-submitted {{PLURAL:25|task|tasks}} that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] From [[m:Special:MyLanguage/Wikimedia Enterprise|Wikimedia Enterprise]]: ** The API now enables 5,000 on-demand API requests per month and twice-monthly HTML snapshots freely (gratis and libre). More information on the updates and also improvements to the software development kits (SDK) are explained on [https://enterprise.wikimedia.com/blog/enhanced-free-api/ the project's blog post]. While Wikimedia Enterprise APIs are designed for high-volume commercial reusers, this change enables many more community use-cases to be built on the service too. ** The Snapshot API (html dumps) have added beta Structured Contents endpoints ([https://enterprise.wikimedia.com/blog/structured-contents-snapshot-api/ blog post on that]) as well as released two beta datasets (English and French Wikipedia) from that endpoint to Hugging Face for public use and feedback ([https://enterprise.wikimedia.com/blog/hugging-face-dataset/ blog post on that]). These pre-parsed data sets enable new options for researchers, developers, and data scientists to use and study the content. '''In depth''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] The Wikidata Query Service (WDQS) is used to get answers to questions using the Wikidata data set. As Wikidata grows, we had to make a major architectural change so that WDQS could remain performant. As part of the [[d:Special:MyLanguage/Wikidata:SPARQL query service/WDQS graph split|WDQS Graph Split project]], we have new SPARQL endpoints available for serving the "[https://query-scholarly.wikidata.org scholarly]" and "[https://query-main.wikidata.org main]" subgraphs of Wikidata. The [http://query.wikidata.org query.wikidata.org endpoint] will continue to serve the full Wikidata graph until March 2025. After this date, it will only serve the main graph. For more information, please see [[d:Special:MyLanguage/Wikidata:SPARQL query service/WDQS backend update/September 2024 scaling update|the announcement on Wikidata]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W39"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:36, 23 September 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27493779 --> == Tech News: 2024-40 == <section begin="technews-2024-W40"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/40|Translations]] are available. '''Updates for editors''' * Readers of [[phab:T375401|42 more wikis]] can now use Dark Mode. If the option is not yet available for logged-out users of your wiki, this is likely because many templates do not yet display well in Dark Mode. Please use the [https://night-mode-checker.wmcloud.org/ night-mode-checker tool] if you are interested in helping to reduce the number of issues. The [[mw:Special:MyLanguage/Recommendations for night mode compatibility on Wikimedia wikis|recommendations page]] provides guidance on this. Dark Mode is enabled on additional wikis once per month. * Editors using the 2010 wikitext editor as their default can access features from the 2017 wikitext editor by adding <code dir=ltr>?veaction=editsource</code> to the URL. If you would like to enable the 2017 wikitext editor as your default, it can be set in [[Special:Preferences#mw-input-wpvisualeditor-newwikitext|your preferences]]. [https://phabricator.wikimedia.org/T239796] * For logged-out readers using the Vector 2022 skin, the "donate" link has been moved from a collapsible menu next to the content area into a more prominent top menu, next to "Create an account". This restores the link to the level of prominence it had in the Vector 2010 skin. [[mw:Readers/2024 Reader and Donor Experiences#Donor Experiences (Key Result WE 3.2 and the related hypotheses)|Learn more]] about the changes related to donor experiences. [https://phabricator.wikimedia.org/T373585] * The CampaignEvents extension provides tools for organizers to more easily manage events, communicate with participants, and promote their events on the wikis. The extension has been [[m:Special:MyLanguage/CampaignEvents/Deployment status|enabled]] on Arabic Wikipedia, Igbo Wikipedia, Swahili Wikipedia, and Meta-Wiki. [[w:zh:Wikipedia:互助客栈/其他#引進CampaignEvents擴充功能|Chinese Wikipedia has decided]] to enable the extension, and discussions on the extension are in progress [[w:es:Wikipedia:Votaciones/2024/Sobre la política de Organizadores de Eventos|on Spanish Wikipedia]] and [[d:Wikidata:Project chat#Enabling the CampaignEvents Extention on Wikidata|on Wikidata]]. To learn how to enable the extension on your wiki, you can visit [[m:Special:MyLanguage/CampaignEvents|the CampaignEvents page on Meta-Wiki]]. * View all {{formatnum:22}} community-submitted {{PLURAL:22|task|tasks}} that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Developers with an account on Wikitech-wiki should [[wikitech:Wikitech/SUL-migration|check if any action is required]] for their accounts. The wiki is being changed to use the single-user-login (SUL) system, and other configuration changes. This change will help reduce the overall complexity for the weekly software updates across all our wikis. '''In depth''' * The [[m:Special:MyLanguage/Tech/Server switch|server switch]] was completed successfully last week with a read-only time of [[wikitech:Switch Datacenter#Past Switches|only 2 minutes 46 seconds]]. This periodic process makes sure that engineers can switch data centers and keep all of the wikis available for readers, even if there are major technical issues. It also gives engineers a chance to do maintenance and upgrades on systems that normally run 24 hours a day, and often helps to reveal weaknesses in the infrastructure. The process involves dozens of software services and hundreds of hardware servers, and requires multiple teams working together. Work over the past few years has reduced the time from 17 minutes down to 2–3 minutes. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/66ZW7B2MG63AESQVTXDIFQBDBS766JGW/] '''Meetings and events''' * October 4–6: [[m:Special:MyLanguage/WikiIndaba conference 2024|WikiIndaba Conference's Hackathon]] in Johannesburg, South Africa * November 4–6: [[mw:Special:MyLanguage/MediaWiki Users and Developers Conference Fall 2024|MediaWiki Users and Developers Conference Fall 2024]] in Vienna, Austria '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W40"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:20, 30 September 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27530062 --> == Tech News: 2024-41 == <section begin="technews-2024-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/41|Translations]] are available. '''Weekly highlight''' * Communities can now request installation of [[mw:Special:MyLanguage/Moderator Tools/Automoderator|Automoderator]] on their wiki. Automoderator is an automated anti-vandalism tool that reverts bad edits based on scores from the new "Revert Risk" machine learning model. You can [[mw:Special:MyLanguage/Extension:AutoModerator/Deploying|read details about the necessary steps]] for installation and configuration. [https://phabricator.wikimedia.org/T336934] '''Updates for editors''' * Translators in wikis where [[mw:Special:MyLanguage/Content translation/Section translation#Try the tool|the mobile experience of Content Translation is available]], can now customize their articles suggestion list from 41 filtering options when using the tool. This topic-based article suggestion feature makes it easy for translators to self-discover relevant articles based on their area of interest and translate them. You can [https://test.wikipedia.org/w/index.php?title=Special:ContentTranslation&active-list=suggestions try it with your mobile device]. [https://phabricator.wikimedia.org/T368422] * View all {{formatnum:12}} community-submitted {{PLURAL:12|task|tasks}} that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * It is now possible for <bdi lang="zxx" dir="ltr"><code><nowiki><syntaxhighlight></nowiki></code></bdi> code blocks to offer readers a "Copy" button if the <bdi lang="zxx" dir="ltr"><code><nowiki>copy=1</nowiki></code></bdi> attribute is [[mw:Special:MyLanguage/Extension:SyntaxHighlight#copy|set on the tag]]. Thanks to SD0001 for these improvements. [https://phabricator.wikimedia.org/T40932] * Customized copyright footer messages on all wikis will be updated. The new versions will use wikitext markup instead of requiring editing raw HTML. [https://phabricator.wikimedia.org/T375789] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Later this month, [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] will be rolled out on several pilot wikis. The final list of the wikis will be published in the second half of the month. If you maintain any tools, bots, or gadgets on [[phab:T376499|these 11 wikis]], and your software is using data about IP addresses or is available for logged-out users, please check if it needs to be updated to work with temporary accounts. [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/For developers|Guidance on how to update the code is available]]. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Rate limiting has been enabled for the code review tools [[Wikitech:Gerrit|Gerrit]] and [[Wikitech:GitLab|GitLab]] to address ongoing issues caused by malicious traffic and scraping. Clients that open too many concurrent connections will be restricted for a few minutes. This rate limiting is managed through [[Wikitech:nftables|nftables]] firewall rules. For more details, see Wikitech's pages on [[Wikitech:Firewall#Throttling with nftables|Firewall]], [[Wikitech:GitLab/Abuse and rate limiting|GitLab limits]] and [[Wikitech:Gerrit/Operations#Throttling IPs|Gerrit operations]]. * Five new wikis have been created: ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q49224|Komering]] ([[w:kge:|<code>w:kge:</code>]]) [https://phabricator.wikimedia.org/T374813] ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q36096|Mooré]] ([[m:mos:|<code>m:mos:</code>]]) [https://phabricator.wikimedia.org/T374641] ** a {{int:project-localized-name-group-wiktionary}} in [[d:Q36213|Madurese]] ([[wikt:mad:|<code>wikt:mad:</code>]]) [https://phabricator.wikimedia.org/T374968] ** a {{int:project-localized-name-group-wikiquote}} in [[d:Q2501174|Gorontalo]] ([[q:gor:|<code>q:gor:</code>]]) [https://phabricator.wikimedia.org/T375088] ** a {{int:project-localized-name-group-wikinews}} in [[d:Q56482|Shan]] ([[n:shn:|<code>n:shn:</code>]]) [https://phabricator.wikimedia.org/T375430] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W41"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:42, 7 October 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27557422 --> == Tech News: 2024-42 == <section begin="technews-2024-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/42|Translations]] are available. '''Updates for editors''' * The Structured Discussion extension (also known as Flow) is starting to be removed. This extension is unmaintained and causes issues. It will be replaced by [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]], which is used on any regular talk page. [[mw:Special:MyLanguage/Structured Discussions/Deprecation#Deprecation timeline|A first set of wikis]] are being contacted. These wikis are invited to stop using Flow, and to move all Flow boards to sub-pages, as archives. At these wikis, a script will move all Flow pages that aren't a sub-page to a sub-page automatically, starting on 22 October 2024. On 28 October 2024, all Flow boards at these wikis will be set in read-only mode. [https://www.mediawiki.org/wiki/Structured_Discussions/Deprecation][https://phabricator.wikimedia.org/T370722] * WMF's Search Platform team is working on making it easier for readers to perform text searches in their language. A [[phab:T332342|change last week]] on over 30 languages makes it easier to find words with accents and other diacritics. This applies to both full-text search and to types of advanced search such as the <bdi lang="en" dir="ltr">''hastemplate''</bdi> and <bdi lang="en" dir="ltr">''incategory''</bdi> keywords. More technical details (including a few other minor search upgrades) are available. [https://www.mediawiki.org/wiki/User:TJones_%28WMF%29/Notes/Language_Analyzer_Harmonization_Notes#ASCII-folding/ICU-folding_%28T332342%29] * View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. For example, [[mw:Special:MyLanguage/Help:Edit check|EditCheck]] was installed at Russian Wikipedia, and fixes were made for some missing user interface styles. '''Updates for technical contributors''' * Editors who use the Toolforge tool [[toolforge:copyvios|Earwig's Copyright Violation Detector]] will now be required to log in with their Wikimedia account before running checks using the "search engine" option. This change is needed to help prevent external bots from misusing the system. Thanks to Chlod for these improvements. [https://en.wikipedia.org/wiki/Wikipedia_talk:New_pages_patrol/Reviewers#Authentication_is_now_required_for_search_engine_checks_on_Earwig's_Copyvio_Tool] * [[m:Special:MyLanguage/Phabricator|Phabricator]] users can create tickets and add comments on existing tickets via Email again. [[mw:Special:MyLanguage/Phabricator/Help#Using email|Sending email to Phabricator]] has been fixed. [https://phabricator.wikimedia.org/T356077] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Some HTML elements in the interface are now wrapped with a <code><nowiki><bdi></nowiki></code> element, to make our HTML output more aligned with Web standards. More changes like this will be coming in future weeks. This change might break some tools that rely on the previous HTML structure of the interface. Note that relying on the HTML structure of the interface is [[mw:Special:MyLanguage/Stable interface policy/Frontend#What is not stable?|not recommended]] and might break at any time. [https://phabricator.wikimedia.org/T375975] '''In depth''' * The latest monthly [[mw:Special:MyLanguage/MediaWiki Product Insights/Reports/September 2024|MediaWiki Product Insights newsletter]] is available. This edition includes: updates on Wikimedia's authentication system, research to simplify feature development in the MediaWiki platform, updates on Parser Unification and MathML rollout, and more. * The latest quarterly [[mw:Technical Community Newsletter/2024/October|Technical Community Newsletter]] is now available. This edition include: research about improving topic suggestions related to countries, improvements to PHPUnit tests, and more. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W42"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:21, 14 October 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27597254 --> == Tech News: 2024-43 == <section begin="technews-2024-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/43|Translations]] are available. '''Weekly highlight''' * The Mobile Apps team has released an [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/Navigation Refresh#Phase 1: Creating a user Profile Menu (T373714)|update]] to the iOS app's navigation, and it is now available in the latest App store version. The team added a new Profile menu that allows for easy access to editor features like Notifications and Watchlist from the Article view, and brings the "Donate" button into a more accessible place for users who are reading an article. This is the first phase of a larger planned [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/Navigation Refresh|navigation refresh]] to help the iOS app transition from a primarily reader-focused app, to an app that fully supports reading and editing. The Wikimedia Foundation has added more editing features and support for on-wiki communication based on volunteer requests in recent years. [[File:IOS App Navigation refresh first phase 05.png|thumb|iOS Wikipedia App's profile menu and contents]] '''Updates for editors''' * Wikipedia readers can now download a browser extension to experiment with some early ideas on potential features that recommend articles for further reading, automatically summarize articles, and improve search functionality. For more details and to stay updated, check out the Web team's [[mw:Special:MyLanguage/Reading/Web/Content Discovery Experiments|Content Discovery Experiments page]] and [[mw:Special:MyLanguage/Newsletter:Web team's projects|subscribe to their newsletter]]. * Later this month, logged-out editors of [[phab:T376499|these 12 wikis]] will start to have [[mw:Special:Mylanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] created. The list may slightly change - some wikis may be removed but none will be added. Temporary account is a new [[mw:Special:MyLanguage/User account types|type of user account]]. It enhances the logged-out editors' privacy and makes it easier for community members to communicate with them. If you maintain any tools, bots, or gadgets on these 12 wikis, and your software is using data about IP addresses or is available for logged-out users, please check if it needs to be updated to work with temporary accounts. [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/For developers|Guidance on how to update the code is available]]. Read more about the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/Updates|deployment plan across all wikis]]. * View all {{formatnum:33}} community-submitted {{PLURAL:33|task|tasks}} that were [[m:Tech/News/Recently resolved community tasks|resolved last week]]. For example, the [[w:nr:Main Page|South Ndebele]], [[w:rsk:Главни бок|Pannonian Rusyn]], [[w:ann:Uwu|Obolo]], [[w:iba:Lambar Keterubah|Iban]] and [[w:tdd:ᥞᥨᥝᥴ ᥘᥣᥲ ᥖᥥᥰ|Tai Nüa]] Wikipedia languages were created last week. [https://www.wikidata.org/wiki/Q36785][https://www.wikidata.org/wiki/Q35660][https://www.wikidata.org/wiki/Q36614][https://www.wikidata.org/wiki/Q33424][https://www.wikidata.org/wiki/Q36556] * It is now possible to create functions on Wikifunctions using Wikidata lexemes, through the new [[f:Z6005|Wikidata lexeme type]] launched last week. When you go to one of these functions, the user interface provides a lexeme selector that helps you pick a lexeme from Wikidata that matches the word you type. After hitting run, your selected lexeme is retrieved from Wikidata, transformed into a Wikidata lexeme type, and passed into the selected function. Read more about this in [[f:Special:MyLanguage/Wikifunctions:Status updates/2024-10-17#Function of the Week: select representation from lexeme|the latest Wikifunctions newsletter]]. '''Updates for technical contributors''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Users of the Wikimedia sites can now format dates more easily in different languages with the new <code dir="ltr">{{[[mw:Special:MyLanguage/Help:Extension:ParserFunctions##timef|#timef]]:…}}</code> parser function. For example, <code dir="ltr"><nowiki>{{#timef:now|date|en}}</nowiki></code> will show as "<bdi lang="en" dir="ltr">{{#timef:now|date|en}}</bdi>". Previously, <code dir="ltr"><nowiki>{{#time:…}}</nowiki></code> could be used to format dates, but this required knowledge of the order of the time and date components and their intervening punctuation. <code dir="ltr">#timef</code> (or <code dir="ltr">#timefl</code> for local time) provides access to the standard date formats that MediaWiki uses in its user interface. This may help to simplify some templates on multi-lingual wikis like Commons and Meta. [https://phabricator.wikimedia.org/T223772][https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Extension:ParserFunctions##timef] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Commons and Meta users can now efficiently [[mw:Special:MyLanguage/Help:Magic words#Localization|retrieve the user's language]] using <code dir="ltr"><nowiki>{{USERLANGUAGE}}</nowiki></code> instead of using <code dir="ltr"><nowiki>{{int:lang}}</nowiki></code>. [https://phabricator.wikimedia.org/T4085] * The [[m:Special:MyLanguage/Product and Technology Advisory Council|Product and Tech Advisory Council]] (PTAC) now has its pilot members with representation across Africa, Asia, Europe, North America and South America. They will work to address the [[Special:MyLanguage/Movement Strategy/Initiatives/Technology Council|Movement Strategy's Technology Council]] initiative of having a co-defined and more resilient technological platform. [https://meta.wikimedia.org/wiki/Movement_Strategy/Initiatives/Technology_Council] '''In depth''' * The latest quarterly [[mw:Special:MyLanguage/Growth/Newsletters/32|Growth newsletter]] is available. It includes: an upcoming Newcomer Homepage Community Updates module, new Community Configuration options, and details on new projects. * The Wikimedia Foundation is [[mw:Special:MyLanguage/Wikimedia Security Team#CNA Partnership|now an official partner of the CVE program]], which is an international effort to catalog publicly disclosed cybersecurity vulnerabilities. This partnership will allow the Security Team to instantly publish [[w:en:Common Vulnerabilities and Exposures|common vulnerabilities and exposures]] (CVE) records that are affecting MediaWiki core, extensions, and skins, along with any other code the Foundation is a steward of. * The [[m:Special:MyLanguage/Community Wishlist|Community Wishlist]] is now [[m:Community Wishlist/Updates#October 16, 2024: Conversations Made Easier: Machine-Translated Wishes Are Here!|testing machine translations]] for Wishlist content. Volunteers can now read machine-translated versions of wishes and dive into discussions even before translators arrive to translate content. '''Meetings and events''' * 24 October - Wiki Education Speaker Series Webinar - [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/N4XTB4G55BUY3M3PNGUAKQWJ7A4UOPAK/ Open Source Tech: Building the Wiki Education Dashboard], featuring Wikimedia interns and a Web developer in the panel. * 20–22 December 2024 - [[m:Special:MyLanguage/Indic Wikimedia Hackathon Bhubaneswar 2024|Indic Wikimedia Hackathon Bhubaneswar 2024]] in Odisha, India. A hackathon for community members, including developers, designers and content editors, to build technical solutions that improve contributors' experiences. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W43"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:52, 21 October 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27634672 --> == Tech News: 2024-44 == <section begin="technews-2024-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/44|Translations]] are available. '''Updates for editors''' * Later in November, the Charts extension will be deployed to the test wikis in order to help identify and fix any issue. A security review is underway to then enable deployment to pilot wikis for broader testing. You can read [[mw:Special:MyLanguage/Extension:Chart/Project/Updates#October 2024: Working towards production deployment|the October project update]] and see the [https://en.wikipedia.beta.wmflabs.org/wiki/Charts latest documentation and examples on Beta Wikipedia]. * View all {{formatnum:32}} community-submitted {{PLURAL:32|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, [[w:en:PediaPress|Pediapress.com]], an external service that creates books from Wikipedia, can now use [[mw:Special:MyLanguage/Wikimedia Maps|Wikimedia Maps]] to include existing pre-rendered infobox map images in their printed books on Wikipedia. [https://phabricator.wikimedia.org/T375761] '''Updates for technical contributors''' * Wikis can use [[:mw:Special:MyLanguage/Extension:GuidedTour|the Guided Tour extension]] to help newcomers understand how to edit. The Guided Tours extension now works with [[mw:Special:MyLanguage/Manual:Dark mode|dark mode]]. Guided Tour maintainers can check their tours to see that nothing looks odd. They can also set <code>emitTransitionOnStep</code> to <code>true</code> to fix an old bug. They can use the new flag <code>allowAutomaticBack</code> to avoid back-buttons they don't want. [https://phabricator.wikimedia.org/T73927#10241528] * Administrators in the Wikimedia projects who use the [[mw:Special:MyLanguage/Help:Extension:Nuke|Nuke Extension]] will notice that mass deletions done with this tool have the "Nuke" tag. This change will make reviewing and analyzing deletions performed with the tool easier. [https://phabricator.wikimedia.org/T366068] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W44"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:56, 28 October 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27668811 --> == Tech News: 2024-45 == <section begin="technews-2024-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/45|Translations]] are available. '''Updates for editors''' * Stewards can now make [[m:Special:MyLanguage/Global blocks|global account blocks]] cause global [[mw:Special:MyLanguage/Autoblock|autoblocks]]. This will assist stewards in preventing abuse from users who have been globally blocked. This includes preventing globally blocked temporary accounts from exiting their session or switching browsers to make subsequent edits for 24 hours. Previously, temporary accounts could exit their current session or switch browsers to continue editing. This is an anti-abuse tool improvement for the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|Temporary Accounts]] project. You can read more about the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/Updates|progress on key features for temporary accounts]]. [https://phabricator.wikimedia.org/T368949] * Wikis that have the [[m:Special:MyLanguage/CampaignEvents/Deployment status|CampaignEvents extension enabled]] can now use the [[m:Special:MyLanguage/Campaigns/Foundation Product Team/Event list#October 29, 2024: Collaboration List launched|Collaboration List]] feature. This list provides a new, easy way for contributors to learn about WikiProjects on their wikis. Thanks to the Campaign team for this work that is part of [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2024-2025/Product %26 Technology OKRs#WE KRs|the 2024/25 annual plan]]. If you are interested in bringing the CampaignEvents extension to your wiki, you can [[m:Special:MyLanguage/CampaignEvents/Deployment status#How to Request the CampaignEvents Extension for your wiki|follow these steps]] or you can reach out to User:Udehb-WMF for help. * The text color for red links will be slightly changed later this week to improve their contrast in light mode. [https://phabricator.wikimedia.org/T370446] * View all {{formatnum:32}} community-submitted {{PLURAL:32|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, on multilingual wikis, users [[phab:T216368|can now]] hide translations from the WhatLinksHere special page. '''Updates for technical contributors''' * XML [[m:Special:MyLanguage/Data dumps|data dumps]] have been temporarily paused whilst a bug is investigated. [https://lists.wikimedia.org/hyperkitty/list/xmldatadumps-l@lists.wikimedia.org/message/BXWJDPO5QI2QMBCY7HO36ELDCRO6HRM4/] '''In depth''' * Temporary Accounts have been deployed to six wikis; thanks to the Trust and Safety Product team for [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|this work]], you can read about [[phab:T340001|the deployment plans]]. Beginning next week, Temporary Accounts will also be enabled on [[phab:T378336|seven other projects]]. If you are active on these wikis and need help migrating your tools, please reach out to [[m:User:Udehb-WMF|User:Udehb-WMF]] for assistance. * The latest quarterly [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2024/October|Language and Internationalization newsletter]] is available. It includes: New languages supported in translatewiki or in MediaWiki; New keyboard input methods for some languages; details about recent and upcoming meetings, and more. '''Meetings and events''' * [[mw:Special:MyLanguage/MediaWiki Users and Developers Conference Fall 2024|MediaWiki Users and Developers Conference Fall 2024]] is happening in Vienna, Austria and online from 4 to 6 November 2024. The conference will feature discussions around the usage of MediaWiki software by and within companies in different industries and will inspire and onboard new users. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W45"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:50, 4 November 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27693917 --> == Tech News: 2024-46 == <section begin="technews-2024-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/46|Translations]] are available. '''Updates for editors''' * On wikis with the [[mw:Special:MyLanguage/Help:Extension:Translate|Translate extension]] enabled, users will notice that the FuzzyBot will now automatically create translated versions of categories used on translated pages. [https://phabricator.wikimedia.org/T285463] * View all {{formatnum:29}} community-submitted {{PLURAL:29|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the submitted task to use the [[mw:Special:MyLanguage/Extension:SecurePoll|SecurePoll extension]] for English Wikipedia's special [[w:en:Wikipedia:Administrator elections|administrator election]] was resolved on time. [https://phabricator.wikimedia.org/T371454] '''Updates for technical contributors''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] In <code dir="ltr">[[mw:MediaWiki_1.44/wmf.2|1.44.0-wmf-2]]</code>, the logic of Wikibase function <code>getAllStatements</code> changed to behave like <code>getBestStatements</code>. Invoking the function now returns a copy of values which are immutable. [https://phabricator.wikimedia.org/T270851] * [https://en.wikipedia.org/api/rest_v1/ Wikimedia REST API] users, such as bot operators and tool maintainers, may be affected by ongoing upgrades. The API will be rerouting some page content endpoints from RESTbase to the newer [[mw:Special:MyLanguage/API:REST API|MediaWiki REST API]] endpoints. The [[phab:T374683|impacted endpoints]] include getting page/revision metadata and rendered HTML content. These changes will be available on testwiki later this week, with other projects to follow. This change should not affect existing functionality, but active users of the impacted endpoints should verify behavior on testwiki, and raise any concerns on the related [[phab:T374683|Phabricator ticket]]. '''In depth''' * Admins and users of the Wikimedia projects [[mw:Special:MyLanguage/Moderator_Tools/Automoderator#Usage|where Automoderator is enabled]] can now monitor and evaluate important metrics related to Automoderator's actions. [https://superset.wmcloud.org/superset/dashboard/unified-automoderator-activity-dashboard/ This Superset dashboard] calculates and aggregates metrics about Automoderator's behaviour on the projects in which it is deployed. Thanks to the Moderator Tools team for this Dashboard; you can visit [[mw:Special:MyLanguage/Moderator Tools/Automoderator/Unified Activity Dashboard|the documentation page]] for more information about this work. [https://phabricator.wikimedia.org/T369488] '''Meetings and events''' * 21 November 2024 ([[m:Special:MyLanguage/Event:Commons community discussion - 21 November 2024 8:00 UTC|8:00 UTC]] & [[m:Special:MyLanguage/Event:Commons community discussion - 21 November 2024 16:00 UTC|16:00 UTC]]) - [[c:Commons:WMF support for Commons/Commons community calls|Community call]] with Wikimedia Commons volunteers and stakeholders to help prioritize support efforts for 2025-2026 Fiscal Year. The theme of this call is how content should be organised on Wikimedia Commons. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W46"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:07, 12 November 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27732268 --> == Tech News: 2024-47 == <section begin="technews-2024-W47"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/47|Translations]] are available. '''Updates for editors''' * Users of Wikimedia sites will now be warned when they create a [[mw:Special:MyLanguage/Help:Redirects|redirect]] to a page that doesn't exist. This will reduce the number of broken redirects to red links in our projects. [https://phabricator.wikimedia.org/T326057] * View all {{formatnum:42}} community-submitted {{PLURAL:42|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, [[mw:Special:MyLanguage/Manual:Pywikibot/Overview|Pywikibot]], which automates work on MediaWiki sites, was upgraded to 9.5.0 on Toolforge. [https://phabricator.wikimedia.org/T378676] '''Updates for technical contributors''' * On wikis that use the [[mw:Special:MyLanguage/Extension:FlaggedRevs|FlaggedRevs extension]], pages created or moved by users with the appropriate permissions are marked as flagged automatically. This feature has not been working recently, and changes fixing it should be deployed this week. Thanks to Daniel and Wargo for working on this. [https://phabricator.wikimedia.org/T379218][https://phabricator.wikimedia.org/T368380] '''In depth''' * There is a new [https://diff.wikimedia.org/2024/11/05/say-hi-to-temporary-accounts-easier-collaboration-with-logged-out-editors-with-better-privacy-protection Diff post] about Temporary Accounts, available in more than 15 languages. Read it to learn about what Temporary Accounts are, their impact on different groups of users, and the plan to introduce the change on all wikis. '''Meetings and events''' * Technical volunteers can now register for the [[mw:Special:MyLanguage/Wikimedia Hackathon 2025|2025 Wikimedia Hackathon]], which will take place in Istanbul, Turkey. [https://pretix.eu/wikimedia/hackathon2025/ Application for travel and accommodation scholarships] is open from '''November 12 to December 10 2024'''. The registration for the event will close in mid-April 2025. The Wikimedia Hackathon is an annual gathering that unites the global technical community to collaborate on existing projects and explore new ideas. * Join the [[C:Special:MyLanguage/Commons:WMF%20support%20for%20Commons/Commons%20community%20calls|Wikimedia Commons community calls]] this week to help prioritize support for Commons which will be planned for 2025–2026. The theme will be how content should be organised on Wikimedia Commons. This is an opportunity for volunteers who work on different things to come together and talk about what matters for the future of the project. The calls will take place '''November 21, 2024, [[m:Special:MyLanguage/Event:Commons community discussion - 21 November 2024 8:00 UTC|8:00 UTC]] and [[m:Special:MyLanguage/Event:Commons community discussion - 21 November 2024 16:00 UTC|16:00 UTC]]'''. * A [[mw:Special:MyLanguage/Wikimedia_Language_and_Product_Localization/Community meetings#29 November 2024|Language community meeting]] will take place '''November 29, 16:00 UTC''' to discuss updates and technical problem-solving. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/47|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W47"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 02:00, 19 November 2024 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27806858 --> == Tech News: 2024-48 == <section begin="technews-2024-W48"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/48|Translations]] are available. '''Updates for editors''' * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] A new version of the standard wikitext editor-mode [[mw:Special:MyLanguage/Extension:CodeMirror|syntax highlighter]] will be available as a [[Special:Preferences#mw-prefsection-betafeatures|beta feature]] later this week. This brings many new features and bug fixes, including right-to-left support, [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Template folding|template folding]], [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Autocompletion|autocompletion]], and an improved search panel. You can learn more on the [[mw:Special:MyLanguage/Help:Extension:CodeMirror|help page]]. * The 2010 wikitext editor now supports common keyboard shortcuts such <bdi lang="zxx" dir="ltr"><code>Ctrl</code>+<code>B</code></bdi> for bold and <bdi lang="zxx" dir="ltr"><code>Ctrl</code>+<code>I</code></bdi> for italics. A full [[mw:Help:Extension:WikiEditor#Keyboard shortcuts|list of all six shortcuts]] is available. Thanks to SD0001 for this improvement. [https://phabricator.wikimedia.org/T62928] * Starting November 28, Flow/Structured Discussions pages will be automatically archived and set to read-only at the following wikis: <bdi>bswiki</bdi>{{int:comma-separator/en}}<bdi>elwiki</bdi>{{int:comma-separator/en}}<bdi>euwiki</bdi>{{int:comma-separator/en}}<bdi>fawiki</bdi>{{int:comma-separator/en}}<bdi>fiwiki</bdi>{{int:comma-separator/en}}<bdi>frwikiquote</bdi>{{int:comma-separator/en}}<bdi>frwikisource</bdi>{{int:comma-separator/en}}<bdi>frwikiversity</bdi>{{int:comma-separator/en}}<bdi>frwikivoyage</bdi>{{int:comma-separator/en}}<bdi>idwiki</bdi>{{int:comma-separator/en}}<bdi>lvwiki</bdi>{{int:comma-separator/en}}<bdi>plwiki</bdi>{{int:comma-separator/en}}<bdi>ptwiki</bdi>{{int:comma-separator/en}}<bdi>urwiki</bdi>{{int:comma-separator/en}}<bdi>viwikisource</bdi>{{int:comma-separator/en}}<bdi>zhwikisource</bdi>. This is done as part of [[mw:Special:MyLanguage/Structured_Discussions/Deprecation|StructuredDiscussions deprecation work]]. If you need any assistance to archive your page in advance, please contact [[m:User:Trizek (WMF)|Trizek (WMF)]]. * View all {{formatnum:25}} community-submitted {{PLURAL:25|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a user creating a new AbuseFilter can now only set the filter to "protected" [[phab:T377765|if it includes a protected variable]]. '''Updates for technical contributors''' * The [[mw:Special:MyLanguage/Extension:CodeEditor|CodeEditor]], which can be used in JavaScript, CSS, JSON, and Lua pages, [[phab:T377663|now offers]] live autocompletion. Thanks to SD0001 for this improvement. The feature can be temporarily disabled on a page by pressing <bdi lang="zxx" dir="ltr"><code>Ctrl</code>+<code>,</code></bdi> and un-selecting "<bdi lang="en" dir="ltr">Live Autocompletion</bdi>". * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Tool-maintainers who use the Graphite system for tracking metrics, need to migrate to the newer Prometheus system. They can check [https://grafana.wikimedia.org/d/K6DEOo5Ik/grafana-graphite-datasource-utilization?orgId=1 this dashboard] and the list in the Description of the [[phab:T350592|task T350592]] to see if their tools are listed, and they should claim metrics and dashboards connected to their tools. They can then disable or migrate all existing metrics by following the instructions in the task. The Graphite service will become read-only in April. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/KLUV4IOLRYXPQFWD6WKKJUHMWE77BMSZ/] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] The [[mw:Special:MyLanguage/NewPP parser report|New PreProcessor parser performance report]] has been fixed to give an accurate count for the number of Wikibase entities accessed. It had previously been resetting after 400 entities. [https://phabricator.wikimedia.org/T279069] '''Meetings and events''' * A [[mw:Special:MyLanguage/Wikimedia_Language_and_Product_Localization/Community meetings#29 November 2024|Language community meeting]] will take place November 29 at [https://zonestamp.toolforge.org/1732896000 16:00 UTC]. There will be presentations on topics like developing language keyboards, the creation of the Mooré Wikipedia, the language support track at [[m:Wiki Indaba|Wiki Indaba]], and a report from the Wayuunaiki community on their experiences with the Incubator and as a new community over the last 3 years. This meeting will be in English and will also have Spanish interpretation. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/48|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W48"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:42, 25 November 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27847039 --> == Tech News: 2024-49 == <section begin="technews-2024-W49"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/49|Translations]] are available. '''Updates for editors''' * Two new parser functions were added this week. The <code dir="ltr"><nowiki>{{</nowiki>[[mw:Special:MyLanguage/Help:Magic words#interwikilink|#interwikilink]]<nowiki>}}</nowiki></code> function adds an [[mw:Special:MyLanguage/Help:Links#Interwiki links|interwiki link]] and the <code dir="ltr"><nowiki>{{</nowiki>[[mw:Special:MyLanguage/Help:Magic words#interlanguagelink|#interlanguagelink]]<nowiki>}}</nowiki></code> function adds an [[mw:Special:MyLanguage/Help:Links#Interlanguage links|interlanguage link]]. These parser functions are useful on wikis where namespaces conflict with interwiki prefixes. For example, links beginning with <bdi lang="zxx" dir="ltr"><code>MOS:</code></bdi> on English Wikipedia [[phab:T363538|conflict with the <code>mos</code> language code prefix of Mooré Wikipedia]]. * Starting this week, Wikimedia wikis no longer support connections using old RSA-based HTTPS certificates, specifically rsa-2048. This change is to improve security for all users. Some older, unsupported browser or smartphone devices will be unable to connect; Instead, they will display a connectivity error. See the [[wikitech:HTTPS/Browser_Recommendations|HTTPS Browser Recommendations page]] for more-detailed information. All modern operating systems and browsers are always able to reach Wikimedia projects. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/CTYEHVNSXUD3NFAAMG3BLZVTVQWJXJAH/] * Starting December 16, Flow/Structured Discussions pages will be automatically archived and set to read-only at the following wikis: <bdi>arwiki</bdi>{{int:comma-separator/en}}<bdi>cawiki</bdi>{{int:comma-separator/en}}<bdi>frwiki</bdi>{{int:comma-separator/en}}<bdi>mediawikiwiki</bdi>{{int:comma-separator/en}}<bdi>orwiki</bdi>{{int:comma-separator/en}}<bdi>wawiki</bdi>{{int:comma-separator/en}}<bdi>wawiktionary</bdi>{{int:comma-separator/en}}<bdi>wikidatawiki</bdi>{{int:comma-separator/en}}<bdi>zhwiki</bdi>. This is done as part of [[mw:Special:MyLanguage/Structured_Discussions/Deprecation|StructuredDiscussions deprecation work]]. If you need any assistance to archive your page in advance, please contact [[m:User:Trizek (WMF)|Trizek (WMF)]]. [https://phabricator.wikimedia.org/T380910] * This month the Chart extension was deployed to production and is now available on Commons and Testwiki. With the security review complete, pilot wiki deployment is expected to start in the first week of December. You can see a working version [[testwiki:Charts|on Testwiki]] and read [[mw:Special:MyLanguage/Extension:Chart/Project/Updates|the November project update]] for more details. * View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug with the "Download as PDF" system was fixed. [https://phabricator.wikimedia.org/T376438] '''Updates for technical contributors''' * In late February, temporary accounts will be rolled out on at least 10 large wikis. This deployment will have a significant effect on the community-maintained code. This is about Toolforge tools, bots, gadgets, and user scripts that use IP address data or that are available for logged-out users. The Trust and Safety Product team wants to identify this code, monitor it, and assist in updating it ahead of the deployment to minimize disruption to workflows. The team asks technical editors and volunteer developers to help identify such tools by adding them to [[mw:Trust and Safety Product/Temporary Accounts/For developers/Impacted tools|this list]]. In addition, review the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/For developers|updated documentation]] to learn how to adjust the tools. Join the discussions on the [[mw:Talk:Trust and Safety Product/Temporary Accounts|project talk page]] or in the [[discord:channels/221049808784326656/1227616742340034722|dedicated thread]] on the [[w:Wikipedia:Discord|Wikimedia Community Discord server (in English)]] for support and to share feedback. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/49|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W49"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:22, 2 December 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27873992 --> == Tech News: 2024-50 == <section begin="technews-2024-W50"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/50|Translations]] are available. '''Weekly highlight''' * Technical documentation contributors can find updated resources, and new ways to connect with each other and the Wikimedia Technical Documentation Team, at the [[mw:Special:MyLanguage/Documentation|Documentation hub]] on MediaWiki.org. This page links to: resources for writing and improving documentation, a new <bdi lang="zxx" dir="ltr">#wikimedia-techdocs</bdi> IRC channel on libera.chat, a listing of past and upcoming documentation events, and ways to request a documentation consultation or review. If you have any feedback or ideas for improvements to the documentation ecosystem, please [[mw:Wikimedia Technical Documentation Team#Contact us|contact the Technical Documentation Team]]. '''Updates for editors''' [[File:Edit Check on Desktop.png|thumb|Layout change for the Edit Check feature]] * Later this week, [[mw:Special:MyLanguage/Edit check|Edit Check]] will be relocated to a sidebar on desktop. Edit check is the feature for new editors to help them follow policies and guidelines. This layout change creates space to present people with [[mw:Edit check#1 November 2024|new Checks]] that appear ''while'' they are typing. The [[mw:Special:MyLanguage/Edit check#Reference Check A/B Test|initial results]] show newcomers encountering Edit Check are 2.2 times more likely to publish a new content edit that includes a reference and is not reverted. * The Chart extension, which enables editors to create data visualizations, was successfully made available on MediaWiki.org and three pilot wikis (Italian, Swedish, and Hebrew Wikipedias). You can see a working examples [[testwiki:Charts|on Testwiki]] and read [[mw:Special:MyLanguage/Extension:Chart/Project/Updates|the November project update]] for more details. * Translators in wikis where the [[mw:Special:MyLanguage/Content translation/Section translation#Try the tool|mobile experience of Content Translation is available]], can now discover articles in Wikiproject campaigns of their interest from the "[https://test.wikipedia.org/w/index.php?title=Special:ContentTranslation&campaign=specialcx&filter-type=automatic&filter-id=collections&active-list=suggestions&from=es&to=en All collection]" category in the articles suggestion feature. Wikiproject Campaign organizers can use this feature, to help translators to discover articles of interest, by adding the <code dir=ltr><nowiki><page-collection> </page-collection></nowiki></code> tag to their campaign article list page on Meta-wiki. This will make those articles discoverable in the Content Translation tool. For more detailed information on how to use the tool and tag, please refer to [[mw:Special:MyLanguage/Translation suggestions: Topic-based & Community-defined lists/How to use the features|the step-by-step guide]]. [https://phabricator.wikimedia.org/T378958] * The [[mw:Special:MyLanguage/Extension:Nuke|Nuke]] feature, which enables administrators to mass delete pages, now has a [[phab:T376379#10310998|multiselect filter for namespace selection]]. This enables users to select multiple specific namespaces, instead of only one or all, when fetching pages for deletion. * The Nuke feature also now [[phab:T364225#10371365|provides links]] to the userpage of the user whose pages were deleted, and to the pages which were not selected for deletion, after page deletions are queued. This enables easier follow-up admin-actions. Thanks to Chlod and the Moderator Tools team for both of these improvements. [https://phabricator.wikimedia.org/T364225#10371365] * The Editing Team is working on making it easier to populate citations from archive.org using the [[mw:Special:MyLanguage/Citoid/Enabling Citoid on your wiki|Citoid]] tool, the auto-filled citation generator. They are asking communities to add two parameters preemptively, <code dir=ltr>archiveUrl</code> and <code dir=ltr>archiveDate</code>, within the TemplateData for each citation template using Citoid. You can see an [https://en.wikipedia.org/w/index.php?title=Template%3ACite_web%2Fdoc&diff=1261320172&oldid=1260788022 example of a change in a template], and a [https://global-search.toolforge.org/?namespaces=10&q=%5C%22citoid%5C%22%3A%20%5C%7B&regex=1&title= list of all relevant templates]. [https://phabricator.wikimedia.org/T374831] * One new wiki has been created: a {{int:project-localized-name-group-wikivoyage}} in [[d:Q9240|Indonesian]] ([[voy:id:|<code>voy:id:</code>]]) [https://phabricator.wikimedia.org/T380726] * Last week, all wikis had problems serving pages to logged-in users and some logged-out users for 30–45 minutes. This was caused by a database problem, and investigation is ongoing. [https://www.wikimediastatus.net/incidents/3g2ckc7bp6l9] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:19}} community-submitted {{PLURAL:19|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug in the [[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add Link]] feature has been fixed. Previously, the list of sections which are excluded from Add Link was partially ignored in certain cases. [https://phabricator.wikimedia.org/T380455][https://phabricator.wikimedia.org/T380329] '''Updates for technical contributors''' * [[mw:Special:MyLanguage/Codex|Codex]], the design system for Wikimedia, now has an early-stage [[gitiles:design/codex-php|implementation in PHP]]. It is available for general use in MediaWiki extensions and Toolforge apps through [https://packagist.org/packages/wikimedia/codex Composer], with use in MediaWiki core coming soon. More information is available in [[wmdoc:design-codex-php/main/index.html|the documentation]]. Thanks to Doğu for the inspiration and many contributions to the library. [https://phabricator.wikimedia.org/T379662] * [https://en.wikipedia.org/api/rest_v1/ Wikimedia REST API] users, such as bot operators and tool maintainers, may be affected by ongoing upgrades. On December 4, the MediaWiki Interfaces team began rerouting page/revision metadata and rendered HTML content endpoints on [[testwiki:|testwiki]] from RESTbase to comparable MediaWiki REST API endpoints. The team encourages active users of these endpoints to verify their tool's behavior on testwiki and raise any concerns on the related [[phab:T374683|Phabricator ticket]] before the end of the year, as they intend to roll out the same change across all Wikimedia projects in early January. These changes are part of the work to replace the outdated [[mw:RESTBase/deprecation|RESTBase]] system. * The [https://wikimediafoundation.limesurvey.net/986172 2024 Developer Satisfaction Survey] is seeking the opinions of the Wikimedia developer community. Please take the survey if you have any role in developing software for the Wikimedia ecosystem. The survey is open until 3 January 2025, and has an associated [[foundation:Legal:Developer Satisfaction Survey 2024 Privacy Statement|privacy statement]]. * There is no new MediaWiki version this week. [https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar] '''Meetings and events''' * The next meeting in the series of [[c:Commons:WMF support for Commons/Commons community calls|Wikimedia Foundation discussions with the Wikimedia Commons community]] will take place on [[m:Event:Commons community discussion - 12 December 2024 08:00 UTC|December 12 at 8:00 UTC]] and [[m:Event:Commons community discussion - 12_December 2024 16:00 UTC|at 16:00 UTC]]. The topic of this call is new media and new contributors. Contributors from all wikis are welcome to attend. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/50|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W50"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:16, 9 December 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27919424 --> == Tech News: 2024-51 == <section begin="technews-2024-W51"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2024/51|Translations]] are available. '''Weekly highlight''' * Interested in improving event management on your home wiki? The [[m:Special:MyLanguage/CampaignEvents|CampaignEvents extension]] offers organizers features like event registration management, event/wikiproject promotion, finding potential participants, and more - all directly on-wiki. If you are an organizer or think your community would benefit from this extension, start a discussion to enable it on your wiki today. To learn more about how to enable this extension on your wiki, visit the [[m:CampaignEvents/Deployment status#How to Request the CampaignEvents Extension for your wiki|deployment status page]]. '''Updates for editors''' * Users of the iOS Wikipedia App in Italy and Mexico on the Italian, Spanish, and English Wikipedias, can see a [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/Personalized Wikipedia Year in Review|personalized Year in Review]] with insights based on their reading and editing history. * Users of the Android Wikipedia App in Sub-Saharan Africa and South Asia can see the new [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/Rabbit Holes|Rabbit Holes]] feature. This feature shows a suggested search term in the Search bar based on the current article being viewed, and a suggested reading list generated from the user’s last two visited articles. * The [[m:Special:MyLanguage/Global reminder bot|global reminder bot]] is now active and running on nearly 800 wikis. This service reminds most users holding temporary rights when they are about to expire, so that they can renew should they want to. See [[m:Global reminder bot/Technical details|the technical details page]] for more information. * The next issue of Tech News will be sent out on 13 January 2025 because of the end of year holidays. Thank you to all of the translators, and people who submitted content or feedback, this year. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was [[phab:T374988|fixed]] in the Android Wikipedia App which had caused translatable SVG images to show the wrong language when they were tapped. '''Updates for technical contributors''' * There is no new MediaWiki version next week. The next deployments will start on 14 January. [https://wikitech.wikimedia.org/wiki/Deployments/Yearly_calendar/2025] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2024/51|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2024-W51"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:24, 16 December 2024 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=27942374 --> == Tech News: 2025-03 == <section begin="technews-2025-W03"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/03|Translations]] are available. '''Weekly highlight''' * The Single User Login system is being updated over the next few months. This is the system which allows users to fill out the login form on one Wikimedia site and get logged in on all others at the same time. It needs to be updated because of the ways that browsers are increasingly restricting cross-domain cookies. To accommodate these restrictions, login and account creation pages will move to a central domain, but it will still appear to the user as if they are on the originating wiki. The updated code will be enabled this week for users on test wikis. This change is planned to roll out to all users during February and March. See [[mw:Special:MyLanguage/MediaWiki Platform Team/SUL3#Deployment|the SUL3 project page]] for more details and a timeline. '''Updates for editors''' * On wikis with [[mw:Special:MyLanguage/Extension:PageAssessments|PageAssessments]] installed, you can now [[mw:Special:MyLanguage/Extension:PageAssessments#Search|filter search results]] to pages in a given WikiProject by using the <code dir=ltr>inproject:</code> keyword. (These wikis: {{int:project-localized-name-arwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-enwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-enwikivoyage/en}}{{int:comma-separator/en}}{{int:project-localized-name-frwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-huwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-newiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-trwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-zhwiki/en}}) [https://phabricator.wikimedia.org/T378868] * One new wiki has been created: a {{int:project-localized-name-group-wikipedia}} in [[d:Q34129|Tigre]] ([[w:tig:|<code>w:tig:</code>]]) [https://phabricator.wikimedia.org/T381377] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:35}} community-submitted {{PLURAL:35|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, there was a bug with updating a user's edit-count after making a rollback edit, which is now fixed. [https://phabricator.wikimedia.org/T382592] '''Updates for technical contributors''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Wikimedia REST API users, such as bot operators and tool maintainers, may be affected by ongoing upgrades. Starting the week of January 13, we will begin rerouting [[phab:T374683|some page content endpoints]] from RESTbase to the newer MediaWiki REST API endpoints for all wiki projects. This change was previously available on testwiki and should not affect existing functionality, but active users of the impacted endpoints may raise issues directly to the [[phab:project/view/6931/|MediaWiki Interfaces Team]] in Phabricator if they arise. * Toolforge tool maintainers can now share their feedback on Toolforge UI, an initiative to provide a web platform that allows creating and managing Toolforge tools through a graphic interface, in addition to existing command-line workflows. This project aims to streamline active maintainers’ tasks, as well as make registration and deployment processes more accessible for new tool creators. The initiative is still at a very early stage, and the Cloud Services team is in the process of collecting feedback from the Toolforge community to help shape the solution to their needs. [[wikitech:Wikimedia Cloud Services team/EnhancementProposals/Toolforge UI|Read more and share your thoughts about Toolforge UI]]. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] For tool and library developers who use the OAuth system: The identity endpoint used for [[mw:Special:MyLanguage/OAuth/For Developers#Identifying the user|OAuth 1]] and [[mw:Special:MyLanguage/OAuth/For Developers#Identifying the user 2|OAuth 2]] returned a JSON object with an integer in its <code>sub</code> field, which was incorrect (the field must always be a string). This has been fixed; the fix will be deployed to Wikimedia wikis on the week of January 13. [https://phabricator.wikimedia.org/T382139] * Many wikis currently use [[:mw:Parsoid/Parser Unification/Cite CSS|Cite CSS]] to render custom footnote markers in Parsoid output. Starting January 20 these rules will be disabled, but the developers ask you to ''not'' clean up your <bdi lang="en" dir="ltr">[[MediaWiki:Common.css]]</bdi> until February 20 to avoid issues during the migration. Your wikis might experience some small changes to footnote markers in Visual Editor and when using experimental Parsoid read mode, but if there are changes these are expected to bring the rendering in line with the legacy parser output. [https://phabricator.wikimedia.org/T370027] '''Meetings and events''' * The next meeting in the series of [[c:Special:MyLanguage/Commons:WMF support for Commons/Commons community calls|Wikimedia Foundation Community Conversations with the Wikimedia Commons community]] will take place on [[m:Special:MyLanguage/Event:Commons community discussion - 15 January 2025 08:00 UTC|January 15 at 8:00 UTC]] and [[m:Special:MyLanguage/Event:Commons community discussion - 15 January 2025 16:00 UTC|at 16:00 UTC]]. The topic of this call is defining the priorities in tool investment for Commons. Contributors from all wikis, especially users who are maintaining tools for Commons, are welcome to attend. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/03|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W03"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:42, 14 January 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28048614 --> == Tech News: 2025-04 == <section begin="technews-2025-W04"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/04|Translations]] are available. '''Updates for editors''' * Administrators can mass-delete multiple pages created by a user or IP address using [[mw:Special:MyLanguage/Extension:Nuke|Extension:Nuke]]. It previously only allowed deletion of pages created in the last 30 days. It can now delete pages from the last 90 days, provided it is targeting a specific user or IP address. [https://phabricator.wikimedia.org/T380846] * On [[phab:P72148|wikis that use]] the [[mw:Special:MyLanguage/Help:Patrolled edits|Patrolled edits]] feature, when the rollback feature is used to revert an unpatrolled page revision, that revision will now be marked as "manually patrolled" instead of "autopatrolled", which is more accurate. Some editors that use [[mw:Special:MyLanguage/Help:New filters for edit review/Filtering|filters]] on Recent Changes may need to update their filter settings. [https://phabricator.wikimedia.org/T302140] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the Visual Editor's "Insert link" feature did not always suggest existing pages properly when an editor started typing, which has now been [[phab:T383497|fixed]]. '''Updates for technical contributors''' * The Structured Discussion extension (also known as Flow) is being progressively removed from the wikis. This extension is unmaintained and causes issues. It will be replaced by [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]], which is used on any regular talk page. [[mw:Special:MyLanguage/Structured Discussions/Deprecation#Deprecation timeline|The last group of wikis]] ({{int:project-localized-name-cawikiquote/en}}{{int:comma-separator/en}}{{int:project-localized-name-fiwikimedia/en}}{{int:comma-separator/en}}{{int:project-localized-name-gomwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kabwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ptwikibooks/en}}{{int:comma-separator/en}}{{int:project-localized-name-sewikimedia/en}}) will soon be contacted. If you have questions about this process, please ping [[m:User:Trizek (WMF)|Trizek (WMF)]] at your wiki. [https://phabricator.wikimedia.org/T380912] * The latest quarterly [[mw:Technical_Community_Newsletter/2025/January|Technical Community Newsletter]] is now available. This edition includes: updates about services from the Data Platform Engineering teams, information about Codex from the Design System team, and more. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/04|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W04"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:36, 21 January 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28129769 --> == Tech News: 2025-05 == <section begin="technews-2025-W05"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/05|Translations]] are available. '''Weekly highlight''' * Patrollers and admins - what information or context about edits or users could help you to make patroller or admin decisions more quickly or easily? The Wikimedia Foundation wants to hear from you to help guide its upcoming annual plan. Please consider sharing your thoughts on this and [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Product & Technology OKRs|13 other questions]] to shape the technical direction for next year. '''Updates for editors''' * iOS Wikipedia App users worldwide can now access a [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/Personalized Wikipedia Year in Review/How your data is used|personalized Year in Review]] feature, which provides insights based on their reading and editing history on Wikipedia. This project is part of a broader effort to help welcome new readers as they discover and interact with encyclopedic content. * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] Edit patrollers now have a new feature available that can highlight potentially problematic new pages. When a page is created with the same title as a page which was previously deleted, a tag ('Recreated') will now be added, which users can filter for in [[{{#special:RecentChanges}}]] and [[{{#special:NewPages}}]]. [https://phabricator.wikimedia.org/T56145] * Later this week, there will be a new warning for editors if they attempt to create a redirect that links to another redirect (a [[mw:Special:MyLanguage/Help:Redirects#Double redirects|double redirect]]). The feature will recommend that they link directly to the second redirect's target page. Thanks to the user SomeRandomDeveloper for this improvement. [https://phabricator.wikimedia.org/T326056] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Wikimedia wikis allow [[w:en:WebAuthn|WebAuthn]]-based second factor checks (such as hardware tokens) during login, but the feature is [[m:Community Wishlist Survey 2023/Miscellaneous/Fix security key (WebAuthn) support|fragile]] and has very few users. The MediaWiki Platform team is temporarily disabling adding new WebAuthn keys, to avoid interfering with the rollout of [[mw:MediaWiki Platform Team/SUL3|SUL3]] (single user login version 3). Existing keys are unaffected. [https://phabricator.wikimedia.org/T378402] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * For developers that use the [[wikitech:Data Platform/Data Lake/Edits/MediaWiki history dumps|MediaWiki History dumps]]: The Data Platform Engineering team has added a couple of new fields to these dumps, to support the [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|Temporary Accounts]] initiative. If you maintain software that reads those dumps, please review your code and the updated documentation, since the order of the fields in the row will change. There will also be one field rename: in the <bdi lang="zxx" dir="ltr"><code>mediawiki_user_history</code></bdi> dump, the <bdi lang="zxx" dir="ltr"><code>anonymous</code></bdi> field will be renamed to <bdi lang="zxx" dir="ltr"><code>is_anonymous</code></bdi>. The changes will take effect with the next release of the dumps in February. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/LKMFDS62TXGDN6L56F4ABXYLN7CSCQDI/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/05|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W05"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:14, 27 January 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28149374 --> == Tech News: 2025-06 == <section begin="technews-2025-W06"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/06|Translations]] are available. '''Updates for editors''' * Editors who use the "Special characters" editing-toolbar menu can now see the 32 special characters you have used most recently, across editing sessions on that wiki. This change should help make it easier to find the characters you use most often. The feature is in both the 2010 wikitext editor and VisualEditor. [https://phabricator.wikimedia.org/T110722] * Editors using the 2010 wikitext editor can now create sublists with correct indentation by selecting the line(s) you want to indent and then clicking the toolbar buttons.[https://phabricator.wikimedia.org/T380438] You can now also insert <code><nowiki><code></nowiki></code> tags using a new toolbar button.[https://phabricator.wikimedia.org/T383010] Thanks to user stjn for these improvements. * Help is needed to ensure the [[mw:Special:MyLanguage/Citoid/Enabling Citoid on your wiki|citation generator]] works properly on each wiki. ** (1) Administrators should update the local versions of the page <code dir=ltr>MediaWiki:Citoid-template-type-map.json</code> to include entries for <code dir=ltr>preprint</code>, <code dir=ltr>standard</code>, and <code dir=ltr>dataset</code>; Here are example diffs to replicate [https://en.wikipedia.org/w/index.php?title=MediaWiki%3ACitoid-template-type-map.json&diff=1189164774&oldid=1165783565 for 'preprint'] and [https://en.wikipedia.org/w/index.php?title=MediaWiki%3ACitoid-template-type-map.json&diff=1270832208&oldid=1270828390 for 'standard' and 'dataset']. ** (2.1) If the citoid map in the citation template used for these types of references is missing, [[mediawikiwiki:Citoid/Enabling Citoid on your wiki#Step 2.a: Create a 'citoid' maps value for each citation template|one will need to be added]]. (2.2) If the citoid map does exist, the TemplateData will need to be updated to include new field names. Here are example updates [https://en.wikipedia.org/w/index.php?title=Template%3ACitation%2Fdoc&diff=1270829051&oldid=1262470053 for 'preprint'] and [https://en.wikipedia.org/w/index.php?title=Template%3ACitation%2Fdoc&diff=1270831369&oldid=1270829480 for 'standard' and 'dataset']. The new fields that may need to be supported are <code dir=ltr>archiveID</code>, <code dir=ltr>identifier</code>, <code dir=ltr>repository</code>, <code dir=ltr>organization</code>, <code dir=ltr>repositoryLocation</code>, <code dir=ltr>committee</code>, and <code dir=ltr>versionNumber</code>. [https://phabricator.wikimedia.org/T383666] * One new wiki has been created: a {{int:project-localized-name-group-wikipedia/en}} in [[d:Q15637215|Central Kanuri]] ([[w:knc:|<code>w:knc:</code>]]) [https://phabricator.wikimedia.org/T385181] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the [[mediawikiwiki:Special:MyLanguage/Help:Extension:Wikisource/Wikimedia OCR|OCR (optical character recognition) tool]] used for Wikisource now supports a new language, Church Slavonic. [https://phabricator.wikimedia.org/T384782] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/06|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W06"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:09, 4 February 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28203495 --> == Tech News: 2025-07 == <section begin="technews-2025-W07"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/07|Translations]] are available. '''Weekly highlight''' * The Product and Technology Advisory Council (PTAC) has published [[m:Special:MyLanguage/Product and Technology Advisory Council/February 2025 draft PTAC recommendation for feedback|a draft of their recommendations]] for the Wikimedia Foundation's Product and Technology department. They have recommended focusing on [[m:Special:MyLanguage/Product and Technology Advisory Council/February 2025 draft PTAC recommendation for feedback/Mobile experiences|mobile experiences]], particularly contributions. They request community [[m:Talk:Product and Technology Advisory Council/February 2025 draft PTAC recommendation for feedback|feedback at the talk page]] by 21 February. '''Updates for editors''' * The "Special pages" portlet link will be moved from the "Toolbox" into the "Navigation" section of the main menu's sidebar by default. This change is because the Toolbox is intended for tools relating to the current page, not tools relating to the site, so the link will be more logically and consistently located. To modify this behavior and update CSS styling, administrators can follow the instructions at [[phab:T385346|T385346]]. [https://phabricator.wikimedia.org/T333211] * As part of this year's work around improving the ways readers discover content on the wikis, the Web team will be running an experiment with a small number of readers that displays some suggestions for related or interesting articles within the search bar. Please check out [[mw:Special:MyLanguage/Reading/Web/Content Discovery Experiments#Experiment 1: Display article recommendations in more prominent locations, search|the project page]] for more information. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Template editors who use TemplateStyles can now customize output for users with specific accessibility needs by using accessibility related media queries (<code dir=ltr>[https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-reduced-motion prefers-reduced-motion]</code>, <code dir=ltr>[https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-reduced-transparency prefers-reduced-transparency]</code>, <code dir=ltr>[https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-contrast prefers-contrast]</code>, and <code dir=ltr>[https://developer.mozilla.org/en-US/docs/Web/CSS/@media/forced-colors forced-colors]</code>). Thanks to user Bawolff for these improvements. [https://phabricator.wikimedia.org/T384175] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:22}} community-submitted {{PLURAL:22|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the global blocks log will now be shown directly on the {{#special:CentralAuth}} page, similarly to global locks, to simplify the workflows for stewards. [https://phabricator.wikimedia.org/T377024] '''Updates for technical contributors''' * Wikidata [[d:Special:MyLanguage/Help:Default values for labels and aliases|now supports a special language as a "default for all languages"]] for labels and aliases. This is to avoid excessive duplication of the same information across many languages. If your Wikidata queries use labels, you may need to update them as some existing labels are getting removed. [https://phabricator.wikimedia.org/T312511] * The function <code dir="ltr">getDescription</code> was invoked on every Wiki page read and accounts for ~2.5% of a page's total load time. The calculated value will now be cached, reducing load on Wikimedia servers. [https://phabricator.wikimedia.org/T383660] * As part of the RESTBase deprecation [[mw:RESTBase/deprecation|effort]], the <code dir="ltr">/page/related</code> endpoint has been blocked as of February 6, 2025, and will be removed soon. This timeline was chosen to align with the deprecation schedules for older Android and iOS versions. The stable alternative is the "<code dir="ltr">morelike</code>" action API in MediaWiki, and [[gerrit:c/mediawiki/services/mobileapps/+/982154/13/pagelib/src/transform/FooterReadMore.js|a migration example]] is available. The MediaWiki Interfaces team [[phab:T376297|can be contacted]] for any questions. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/GFC2IJO7L4BWO3YTM7C5HF4MCCBE2RJ2/] '''In depth''' * The latest quarterly [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2025/January|Language and Internationalization newsletter]] is available. It includes: Updates about the "Contribute" menu; details on some of the newest language editions of Wikipedia; details on new languages supported by the MediaWiki interface; updates on the Community-defined lists feature; and more. * The latest [[mw:Extension:Chart/Project/Updates#January 2025: Better visibility into charts and tabular data usage|Chart Project newsletter]] is available. It includes updates on the progress towards bringing better visibility into global charts usage and support for categorizing pages in the Data namespace on Commons. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/07|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W07"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:12, 11 February 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28231022 --> == Tech News: 2025-08 == <section begin="technews-2025-W08"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/08|Translations]] are available. '''Weekly highlight''' * Communities using growth tools can now showcase one event on the <code>{{#special:Homepage}}</code> for newcomers. This feature will help newcomers to be informed about editing activities they can participate in. Administrators can create a new event to showcase at <code>{{#special:CommunityConfiguration}}</code>. To learn more about this feature, please read [[diffblog:2025/02/12/community-updates-module-connecting-newcomers-to-your-initiatives/|the Diff post]], have a look [[mw:Special:MyLanguage/Help:Growth/Tools/Community updates module|at the documentation]], or contact [[mw:Talk:Growth|the Growth team]]. '''Updates for editors''' [[File:Page Frame Features on desktop.png|thumb|Highlighted talk pages improvements]] * Starting next week, talk pages at these wikis – {{int:project-localized-name-eswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-frwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-itwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-jawiki/en}} – will get [[diffblog:2024/05/02/making-talk-pages-better-for-everyone/|a new design]]. This change was extensively tested as a Beta feature and is the last step of [[mw:Special:MyLanguage/Talk pages project/Feature summary|talk pages improvements]]. [https://phabricator.wikimedia.org/T379102] * You can now navigate to view a redirect page directly from its action pages, such as the history page. Previously, you were forced to first go to the redirect target. This change should help editors who work with redirects a lot. Thanks to user stjn for this improvement. [https://phabricator.wikimedia.org/T5324] * When a Cite reference is reused many times, wikis currently show either numbers like "1.23" or localized alphabetic markers like "a b c" in the reference list. Previously, if there were so many reuses that the alphabetic markers were all used, [[MediaWiki:Cite error references no backlink label|an error message]] was displayed. As part of the work to [[phab:T383036|modernize Cite customization]], these errors will no longer be shown and instead the backlinks will fall back to showing numeric markers like "1.23" once the alphabetic markers are all used. * The log entries for each change to an editor's user-groups are now clearer by specifying exactly what has changed, instead of the plain before and after listings. Translators can [[phab:T369466|help to update the localized versions]]. Thanks to user Msz2001 for these improvements. * A new filter has been added to the [[{{#special:Nuke}}]] tool, which allows administrators to mass delete pages, to enable users to filter for pages in a range of page sizes (in bytes). This allows, for example, deleting pages only of a certain size or below. [https://phabricator.wikimedia.org/T378488] * Non-administrators can now check which pages are able to be deleted using the [[{{#special:Nuke}}]] tool. Thanks to user MolecularPilot for this and the previous improvements. [https://phabricator.wikimedia.org/T376378] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:25}} community-submitted {{PLURAL:25|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was fixed in the configuration for the AV1 video file format, which enables these files to play again. [https://phabricator.wikimedia.org/T382193] '''Updates for technical contributors''' * Parsoid Read Views is going to be rolling out to most Wiktionaries over the next few weeks, following the successful transition of Wikivoyage to Parsoid Read Views last year. For more information, see the [[mw:Special:MyLanguage/Parsoid/Parser Unification|Parsoid/Parser Unification]] project page. [https://phabricator.wikimedia.org/T385923][https://phabricator.wikimedia.org/T371640] * Developers of tools that run on-wiki should note that <code dir=ltr>mw.Uri</code> is deprecated. Tools requiring <code dir=ltr>mw.Uri</code> must explicitly declare <code dir=ltr>mediawiki.Uri</code> as a ResourceLoader dependency, and should migrate to the browser native <code dir=ltr>URL</code> API soon. [https://phabricator.wikimedia.org/T384515] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/08|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W08"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:16, 17 February 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28275610 --> == Tech News: 2025-09 == <section begin="technews-2025-W09"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/09|Translations]] are available. '''Updates for editors''' * Administrators can now customize how the [[m:Special:MyLanguage/User language|Babel feature]] creates categories using [[{{#special:CommunityConfiguration/Babel}}]]. They can rename language categories, choose whether they should be auto-created, and adjust other settings. [https://phabricator.wikimedia.org/T374348] * The <bdi lang="en" dir="ltr">[https://www.wikimedia.org/ wikimedia.org]</bdi> portal has been updated – and is receiving some ongoing improvements – to modernize and improve the accessibility of our portal pages. It now has better support for mobile layouts, updated wording and links, and better language support. Additionally, all of the Wikimedia project portals, such as <bdi lang="en" dir="ltr">[https://wikibooks.org wikibooks.org]</bdi>, now support dark mode when a reader is using that system setting. [https://phabricator.wikimedia.org/T373204][https://phabricator.wikimedia.org/T368221][https://meta.wikimedia.org/wiki/Project_portals] * One new wiki has been created: a {{int:project-localized-name-group-wiktionary/en}} in [[d:Q33965|Santali]] ([[wikt:sat:|<code>wikt:sat:</code>]]) [https://phabricator.wikimedia.org/T386619] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was fixed that prevented clicking on search results in the web-interface for some Firefox for Android phone configurations. [https://phabricator.wikimedia.org/T381289] '''Meetings and events''' * The next Language Community Meeting is happening soon, February 28th at [https://zonestamp.toolforge.org/1740751200 14:00 UTC]. This week's meeting will cover: highlights and technical updates on keyboard and tools for the Sámi languages, Translatewiki.net contributions from the Bahasa Lampung community in Indonesia, and technical Q&A. If you'd like to join, simply [[mw:Wikimedia Language and Product Localization/Community meetings#28 February 2025|sign up on the wiki page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/09|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W09"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:41, 25 February 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28296129 --> == Tech News: 2025-10 == <section begin="technews-2025-W10"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/10|Translations]] are available. '''Updates for editors''' * All logged-in editors using the mobile view can now edit a full page. The "{{int:Minerva-page-actions-editfull}}" link is accessible from the "{{int:minerva-page-actions-overflow}}" menu in the toolbar. This was previously only available to editors using the [[mw:Special:MyLanguage/Reading/Web/Advanced mobile contributions|Advanced mobile contributions]] setting. [https://phabricator.wikimedia.org/T387180] * Interface administrators can now help to remove the deprecated Cite CSS code matching "<code dir="ltr">mw-ref</code>" from their local <bdi lang="en" dir="ltr">[[MediaWiki:Common.css]]</bdi>. The list of wikis in need of cleanup, and the code to remove, [https://global-search.toolforge.org/?q=mw-ref%5B%5E-a-z%5D&regex=1&namespaces=8&title=.*css can be found with this global search] and in [https://ace.wikipedia.org/w/index.php?title=MediaWiki:Common.css&oldid=145662#L-139--L-144 this example], and you can learn more about how to help on the [[mw:Parsoid/Parser Unification/Cite CSS|CSS migration project page]]. The Cite footnote markers ("<code dir="ltr">[1]</code>") are now rendered by [[mw:Special:MyLanguage/Parsoid|Parsoid]], and the deprecated CSS is no longer needed. The CSS for backlinks ("<code dir="ltr">mw:referencedBy</code>") should remain in place for now. This cleanup is expected to cause no visible changes for readers. Please help to remove this code before March 20, after which the development team will do it for you. * When editors embed a file (e.g. <code><nowiki>[[File:MediaWiki.png]]</nowiki></code>) on a page that is protected with cascading protection, the software will no longer restrict edits to the file description page, only to new file uploads.[https://phabricator.wikimedia.org/T24521] In contrast, transcluding a file description page (e.g. <code><nowiki>{{:File:MediaWiki.png}}</nowiki></code>) will now restrict edits to the page.[https://phabricator.wikimedia.org/T62109] * When editors revert a file to an earlier version it will now require the same permissions as ordinarily uploading a new version of the file. The software now checks for 'reupload' or 'reupload-own' rights,[https://phabricator.wikimedia.org/T304474] and respects cascading protection.[https://phabricator.wikimedia.org/T140010] * When administrators are listing pages for deletion with the Nuke tool, they can now also list associated talk pages and redirects for deletion, alongside pages created by the target, rather than needing to manually delete these pages afterwards. [https://phabricator.wikimedia.org/T95797] * The [[m:Special:MyLanguage/Tech/News/2025/03|previously noted]] update to Single User Login, which will accommodate browser restrictions on cross-domain cookies by moving login and account creation to a central domain, will now roll out to all users during March and April. The team plans to enable it for all new account creation on [[wikitech:Deployments/Train#Tuesday|Group0]] wikis this week. See [[mw:Special:MyLanguage/MediaWiki Platform Team/SUL3#Deployment|the SUL3 project page]] for more details and an updated timeline. * Since last week there has been a bug that shows some interface icons as black squares until the page has fully loaded. It will be fixed this week. [https://phabricator.wikimedia.org/T387351] * One new wiki has been created: a {{int:project-localized-name-group-wikipedia/en}} in [[d:Q2044560|Sylheti]] ([[w:syl:|<code>w:syl:</code>]]) [https://phabricator.wikimedia.org/T386441] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was fixed with loading images in very old versions of the Firefox browser on mobile. [https://phabricator.wikimedia.org/T386400] '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.19|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/10|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W10"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 02:30, 4 March 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28334563 --> == Tech News: 2025-11 == <section begin="technews-2025-W11"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/11|Translations]] are available. '''Updates for editors''' * Editors who use password managers at multiple wikis may notice changes in the future. The way that our wikis provide information to password managers about reusing passwords across domains has recently been updated, so some password managers might now offer you login credentials that you saved for a different Wikimedia site. Some password managers already did this, and are now doing it for more Wikimedia domains. This is part of the [[mw:Special:MyLanguage/MediaWiki Platform Team/SUL3|SUL3 project]] which aims to improve how our unified login works, and to keep it compatible with ongoing changes to the web-browsers we use. [https://phabricator.wikimedia.org/T385520][https://phabricator.wikimedia.org/T384844] * The Wikipedia Apps Team is inviting interested users to help improve Wikipedia’s offline and limited internet use. After discussions in [[m:Afrika Baraza|Afrika Baraza]] and the last [[m:Special:MyLanguage/ESEAP Hub/Meetings|ESEAP call]], key challenges like search, editing, and offline access are being explored, with upcoming focus groups to dive deeper into these topics. All languages are welcome, and interpretation will be available. Want to share your thoughts? [[mw:Special:MyLanguage/Wikimedia Apps/Improving Wikipedia Mobile Apps for Offline & Limited Internet Use|Join the discussion]] or email <bdi lang="en" dir="ltr">aramadan@wikimedia.org</bdi>! * All wikis will be read-only for a few minutes on March 19. This is planned at [https://zonestamp.toolforge.org/1742392800 14:00 UTC]. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.20|MediaWiki]] '''In depth''' * The latest quarterly [[mw:Special:MyLanguage/Growth/Newsletters/33|Growth newsletter]] is available. It includes: the launch of the Community Updates module, the most recent changes in Community Configuration, and the upcoming test of in-article suggestions for first-time editors. * An old API that was previously used in the Android Wikipedia app is being removed at the end of March. There are no current software uses, but users of the app with a version that is older than 6 months by the time of removal (2025-03-31), will no longer have access to the Suggested Edits feature, until they update their app. You can [[diffblog:2025/02/24/sunset-of-wikimedia-recommendation-api/|read more details about this change]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/11|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W11"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:09, 10 March 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28372257 --> == Tech News: 2025-12 == <section begin="technews-2025-W12"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/12|Translations]] are available. '''Weekly highlight''' * Twice a year, around the equinoxes, the Wikimedia Foundation's Site Reliability Engineering (SRE) team performs [[m:Special:MyLanguage/Tech/Server switch|a datacenter server switchover]], redirecting all traffic from one primary server to its backup. This provides reliability in case of a crisis, as we can always fall back on the other datacenter. [http://listen.hatnote.com/ Thanks to the Listen to Wikipedia] tool, you can hear the switchover take place: Before it begins, you'll hear the steady stream of edits; Then, as the system enters a brief read-only phase, the sound stops for a couple of minutes, before resuming after the switchover. You can [[diffblog:2025/03/12/hear-that-the-wikis-go-silent-twice-a-year/|read more about the background and details of this process on the Diff blog]]. If you want to keep an ear out for the next server switchover, listen to the wikis on [https://zonestamp.toolforge.org/1742392800 March 19 at 14:00 UTC]. '''Updates for editors''' * The [https://test.wikipedia.org/w/index.php?title=Special:ContentTranslation&filter-type=automatic&filter-id=previous-edits&active-list=suggestions&from=en&to=es improved Content Translation tool dashboard] is now available in [[phab:T387820|10 Wikipedias]] and will be available for all Wikipedias [[phab:T387821|soon]]. With [[mw:Special:MyLanguage/Content translation#Improved translation experience|the unified dashboard]], desktop users can now: Translate new sections of an article; Discover and access topic-based [https://ig.m.wikipedia.org/w/index.php?title=Special:ContentTranslation&active-list=suggestions&from=en&to=ig&filter-type=automatic&filter-id=previous-edits article suggestion filters] (initially available only for mobile device users); Discover and access the [[mw:Special:MyLanguage/Translation suggestions: Topic-based & Community-defined lists|Community-defined lists]] filter, also known as "Collections", from wiki-projects and campaigns. * On Wikimedia Commons, a [[c:Commons:WMF support for Commons/Upload Wizard Improvements#Improve category selection|new system to select the appropriate file categories]] has been introduced: if a category has one or more subcategories, users will be able to click on an arrow that will open the subcategories directly within the form, and choose the correct one. The parent category name will always be shown on top, and it will always be possible to come back to it. This should decrease the amount of work for volunteers in fixing/creating new categories. The change is also available on mobile. These changes are part of planned improvements to the UploadWizard. * The Community Tech team is seeking wikis to join a pilot for the [[m:Special:MyLanguage/Community Wishlist Survey 2023/Multiblocks|Multiblocks]] feature and a refreshed Special:Block page in late March. Multiblocks enables administrators to impose multiple different types of blocks on the same user at the same time. If you are an admin or steward and would like us to discuss joining the pilot with your community, please leave a message on the [[m:Talk:Community Wishlist Survey 2023/Multiblocks|project talk page]]. * Starting March 25, the Editing team will test a new feature for Edit Check at [[phab:T384372|12 Wikipedias]]: [[mw:Special:MyLanguage/Help:Edit check#Multi-check|Multi-Check]]. Half of the newcomers on these wikis will see all [[mw:Special:MyLanguage/Help:Edit check#ref|Reference Checks]] during their edit session, while the other half will continue seeing only one. The goal of this test is to see if users are confused or discouraged when shown multiple Reference Checks (when relevant) within a single editing session. At these wikis, the tags used on edits that show References Check will be simplified, as multiple tags could be shown within a single edit. Changes to the tags are documented [[phab:T373949|on Phabricator]]. [https://phabricator.wikimedia.org/T379131] * The [[m:Special:MyLanguage/Global reminder bot|Global reminder bot]], which is a service for notifying users that their temporary user-rights are about to expire, now supports using the localized name of the user-rights group in the message heading. Translators can see the [[m:Global reminder bot/Translation|listing of existing translations and documentation]] to check if their language needs updating or creation. * The [[Special:GlobalPreferences|GlobalPreferences]] gender setting, which is used for how the software should refer to you in interface messages, now works as expected by overriding the local defaults. [https://phabricator.wikimedia.org/T386584] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:26}} community-submitted {{PLURAL:26|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the Wikipedia App for Android had a bug fixed for when a user is browsing and searching in multiple languages. [https://phabricator.wikimedia.org/T379777] '''Updates for technical contributors''' * Later this week, the way that Codex styles are loaded will be changing. There is a small risk that this may result in unstyled interface message boxes on certain pages. User generated content (e.g. templates) is not impacted. Gadgets may be impacted. If you see any issues [[phab:T388847|please report them]]. See the linked task for details, screenshots, and documentation on how to fix any affected gadgets. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.21|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/12|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W12"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:48, 17 March 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28412594 --> == Tech News: 2025-13 == <section begin="technews-2025-W13"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/13|Translations]] are available. '''Weekly highlight''' * The Wikimedia Foundation is seeking your feedback on the [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Product & Technology OKRs|drafts of the objectives and key results that will shape the Foundation's Product and Technology priorities]] for the next fiscal year (starting in July). The objectives are broad high-level areas, and the key-results are measurable ways to track the success of their objectives. Please share your feedback on the talkpage, in any language, ideally before the end of April. '''Updates for editors''' * The [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents extension]] will be released to multiple wikis (see [[m:Special:MyLanguage/CampaignEvents/Deployment status#Global Deployment Plan|deployment plan]] for details) in April 2025, and the team has begun the process of engaging communities on the identified wikis. The extension provides tools to organize, manage, and promote collaborative activities (like events, edit-a-thons, and WikiProjects) on the wikis. The extension has three tools: [[m:Special:MyLanguage/Event Center/Registration|Event Registration]], [[m:Special:MyLanguage/CampaignEvents/Collaboration list|Collaboration List]], and [[m:Special:MyLanguage/Campaigns/Foundation Product Team/Invitation list|Invitation Lists]]. It is currently on 13 Wikipedias, including English Wikipedia, French Wikipedia, and Spanish Wikipedia, as well as Wikidata. Questions or requests can be directed to the [[mw:Help talk:Extension:CampaignEvents|extension talk page]] or in Phabricator (with <bdi lang="en" dir="ltr" style="white-space: nowrap;">#campaigns-product-team</bdi> tag). * Starting the week of March 31st, wikis will be able to set which user groups can view private registrants in [[m:Special:MyLanguage/Event Center/Registration|Event Registration]], as part of the [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents]] extension. By default, event organizers and the local wiki admins will be able to see private registrants. This is a change from the current behavior, in which only event organizers can see private registrants. Wikis can change the default setup by [[m:Special:MyLanguage/Requesting wiki configuration changes|requesting a configuration change]] in Phabricator (and adding the <bdi lang="en" dir="ltr" style="white-space: nowrap;">#campaigns-product-team</bdi> tag). Participants of past events can cancel their registration at any time. * Administrators at wikis that have a customized <bdi lang="en" dir="ltr">[[MediaWiki:Sidebar]]</bdi> should check that it contains an entry for the {{int:specialpages}} listing. If it does not, they should add it using <code dir=ltr style="white-space: nowrap;">* specialpages-url|specialpages</code>. Wikis with a default sidebar will see the link moved from the page toolbox into the sidebar menu in April. [https://phabricator.wikimedia.org/T388927] * The Minerva skin (mobile web) combines both Notice and Alert notifications within the bell icon ([[File:OOjs UI icon bell.svg|16px|link=|class=skin-invert]]). There was a long-standing bug where an indication for new notifications was only shown if you had unseen Alerts. This bug is now fixed. In the future, Minerva users will notice a counter atop the bell icon when you have 1 or more unseen Notices and/or Alerts. [https://phabricator.wikimedia.org/T344029] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * VisualEditor has introduced a [[mw:VisualEditor/Hooks|new client-side hook]] for developers to use when integrating with the VisualEditor target lifecycle. This hook should replace the existing lifecycle-related hooks, and be more consistent between different platforms. In addition, the new hook will apply to uses of VisualEditor outside of just full article editing, allowing gadgets to interact with the editor in DiscussionTools as well. The Editing Team intends to deprecate and eventually remove the old lifecycle hooks, so any use cases that this new hook does not cover would be of interest to them and can be [[phab:T355555|shared in the task]]. * Developers who use the <code dir=ltr>mw.Api</code> JavaScript library, can now identify the tool using it with the <code dir=ltr>userAgent</code> parameter: <code dir=ltr>var api = new mw.Api( { userAgent: 'GadgetNameHere/1.0.1' } );</code>. If you maintain a gadget or user script, please set a user agent, because it helps with library and server maintenance and with differentiating between legitimate and illegitimate traffic. [https://phabricator.wikimedia.org/T373874][https://foundation.wikimedia.org/wiki/Policy:Wikimedia_Foundation_User-Agent_Policy] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.22|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/13|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W13"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:42, 24 March 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28443127 --> == Tech News: 2025-14 == <section begin="technews-2025-W14"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/14|Translations]] are available. '''Updates for editors''' * The Editing team is working on a new [[mw:Special:MyLanguage/Edit Check|Edit check]]: [[mw:Special:MyLanguage/Edit check#26 March 2025|Peacock check]]. This check's goal is to identify non-neutral terms while a user is editing a wikipage, so that they can be informed that their edit should perhaps be changed before they publish it. This project is at the early stages, and the team is looking for communities' input: [[phab:T389445|in this Phabricator task]], they are gathering on-wiki policies, templates used to tag non-neutral articles, and the terms (jargon and keywords) used in edit summaries for the languages they are currently researching. You can participate by editing the table on Phabricator, commenting on the task, or directly messaging [[m:user:Trizek (WMF)|Trizek (WMF)]]. * [[mw:Special:MyLanguage/MediaWiki Platform Team/SUL3|Single User Login]] has now been updated on all wikis to move login and account creation to a central domain. This makes user login compatible with browser restrictions on cross-domain cookies, which have prevented users of some browsers from staying logged in. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:35}} community-submitted {{PLURAL:35|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Starting on March 31st, the MediaWiki Interfaces team will begin a limited release of generated OpenAPI specs and a SwaggerUI-based sandbox experience for [[mw:Special:MyLanguage/API:REST API|MediaWiki REST APIs]]. They invite developers from a limited group of non-English Wikipedia communities (Arabic, German, French, Hebrew, Interlingua, Dutch, Chinese) to review the documentation and experiment with the sandbox in their preferred language. In addition to these specific Wikipedia projects, the sandbox and OpenAPI spec will be available on the [[testwiki:Special:RestSandbox|on the test wiki REST Sandbox special page]] for developers with English as their preferred language. During the preview period, the MediaWiki Interfaces Team also invites developers to [[mw:MediaWiki Interfaces Team/Feature Feedback/REST Sandbox|share feedback about your experience]]. The preview will last for approximately 2 weeks, after which the sandbox and OpenAPI specs will be made available across all wiki projects. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.23|MediaWiki]] '''In depth''' * Sometimes a small, [[gerrit:c/operations/cookbooks/+/1129184|one line code change]] can have great significance: in this case, it means that for the first time in years we're able to run all of the stack serving <bdi lang="en" dir="ltr">[http://maps.wikimedia.org/ maps.wikimedia.org]</bdi> - a host dedicated to serving our wikis and their multi-lingual maps needs - from a single core datacenter, something we test every time we perform a [[m:Special:MyLanguage/Tech/Server switch|datacenter switchover]]. This is important because it means that in case one of our datacenters is affected by a catastrophe, we'll still be able to serve the site. This change is the result of [[phab:T216826|extensive work]] by two developers on porting the last component of the maps stack over to [[w:en:Kubernetes|kubernetes]], where we can allocate resources more efficiently than before, thus we're able to withstand more traffic in a single datacenter. This work involved a lot of complicated steps because this software, and the software libraries it uses, required many long overdue upgrades. This type of work makes the Wikimedia infrastructure more sustainable. '''Meetings and events''' * [[mw:Special:MyLanguage/MediaWiki Users and Developers Workshop Spring 2025|MediaWiki Users and Developers Workshop Spring 2025]] is happening in Sandusky, USA, and online, from 14–16 May 2025. The workshop will feature discussions around the usage of MediaWiki software by and within companies in different industries and will inspire and onboard new users. Registration and presentation signup is now available at the workshop's website. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/14|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W14"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:05, 1 April 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28473566 --> == Tech News: 2025-15 == <section begin="technews-2025-W15"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/15|Translations]] are available. '''Updates for editors''' * From now on, [[m:Special:MyLanguage/Interface administrators|interface admins]] and [[m:Special:MyLanguage/Central notice administrators|centralnotice admins]] are technically required to enable [[m:Special:MyLanguage/Help:Two-factor authentication|two-factor authentication]] before they can use their privileges. In the future this might be expanded to more groups with advanced user-rights. [https://phabricator.wikimedia.org/T150898] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * The Design System Team is preparing to release the next major version of Codex (v2.0.0) on April 29. Editors and developers who use CSS from Codex should see the [[mw:Codex/Release Timeline/2.0|2.0 overview documentation]], which includes guidance related to a few of the breaking changes such as <code dir=ltr style="white-space: nowrap;">font-size</code>, <code dir=ltr style="white-space: nowrap;">line-height</code>, and <code dir=ltr style="white-space: nowrap;">size-icon</code>. * The results of the [[mw:Developer Satisfaction Survey/2025|Developer Satisfaction Survey (2025)]]  are now available. Thank you to all participants. These results help the Foundation decide what to work on next and to review what they recently worked on. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.24|MediaWiki]] '''Meetings and events''' * The [[mw:Special:MyLanguage/Wikimedia Hackathon 2025|2025 Wikimedia Hackathon]] will take place in Istanbul, Turkey, between 2–4 May. Registration for attending the in-person event will close on 13 April. Before registering, please note the potential need for a [https://www.mfa.gov.tr/turkish-representations.en.mfa visa] or [https://www.mfa.gov.tr/visa-information-for-foreigners.en.mfa e-visa] to enter the country. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/15|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W15"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:52, 7 April 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28507470 --> == Tech News: 2025-16 == <section begin="technews-2025-W16"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/16|Translations]] are available. '''Weekly highlight''' * Later this week, the default thumbnail size will be increased from 220px to 250px. This changes how pages are shown in all wikis and has been requested by some communities for many years, but wasn't previously possible due to technical limitations. [https://phabricator.wikimedia.org/T355914] * File thumbnails are now stored in discrete sizes. If a page specifies a thumbnail size that's not among the standard sizes (20, 40, 60, 120, 250, 330, 500, 960), then MediaWiki will pick the closest larger thumbnail size but will tell the browser to downscale it to the requested size. In these cases, nothing will change visually but users might load slightly larger images. If it doesn't matter which thumbnail size is used in a page, please pick one of the standard sizes to avoid the extra in-browser down-scaling step. [https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Images#Thumbnail_sizes][https://phabricator.wikimedia.org/T355914] '''Updates for editors''' * The Wikimedia Foundation are working on a system called [[m:Edge Uniques|Edge Uniques]] which will enable [[:w:en:A/B testing|A/B testing]], help protect against [[:w:en:Denial-of-service attack|Distributed denial-of-service attacks]] (DDoS attacks), and make it easier to understand how many visitors the Wikimedia sites have. This is so that they can more efficiently build tools which help readers, and make it easier for readers to find what they are looking for. * To improve security for users, a small percentage of logins will now require that the account owner input a one-time password [[mw:Special:MyLanguage/Help:Extension:EmailAuth|emailed to their account]]. It is recommended that you [[Special:Preferences#mw-prefsection-personal-email|check]] that the email address on your account is set correctly, and that it has been confirmed, and that you have an email set for this purpose. [https://phabricator.wikimedia.org/T390662] * "Are you interested in taking a short survey to improve tools used for reviewing or reverting edits on your Wiki?" This question will be [[phab:T389401|asked at 7 wikis starting next week]], on Recent Changes and Watchlist pages. The [[mw:Special:MyLanguage/Moderator Tools|Moderator Tools team]] wants to know more about activities that involve looking at new edits made to your Wikimedia project, and determining whether they adhere to your project's policies. * On April 15, the full Wikidata graph will no longer be supported on <bdi lang="zxx" dir="ltr">[https://query.wikidata.org/ query.wikidata.org]</bdi>. After this date, scholarly articles will be available through <bdi lang="zxx" dir="ltr" style="white-space:nowrap;">[https://query-scholarly.wikidata.org/ query-scholarly.wikidata.org]</bdi>, while the rest of the data hosted on Wikidata will be available through the <bdi lang="zxx" dir="ltr">[https://query.wikidata.org/ query.wikidata.org]</bdi> endpoint. This is part of the scheduled split of the Wikidata Graph, which was [[d:Special:MyLanguage/Wikidata:SPARQL query service/WDQS backend update/September 2024 scaling update|announced in September 2024]]. More information is [[d:Wikidata:SPARQL query service/WDQS graph split|available on Wikidata]]. * The latest quarterly [[m:Special:MyLanguage/Wikimedia Apps/Newsletter/First quarter of 2025|Wikimedia Apps Newsletter]] is now available. It covers updates, experiments, and improvements made to the Wikipedia mobile apps. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * The latest quarterly [[mw:Technical Community Newsletter/2025/April|Technical Community Newsletter]] is now available. This edition includes: an invitation for tool maintainers to attend the Toolforge UI Community Feedback Session on April 15th; recent community metrics; and recent technical blog posts. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.25|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/16|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W16"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:24, 15 April 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28540654 --> == Tech News: 2025-17 == <section begin="technews-2025-W17"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/17|Translations]] are available. '''Updates for editors''' * [[f:Special:MyLanguage/Wikifunctions:Main Page|Wikifunctions]] is now integrated with [[w:dag:Solɔɣu|Dagbani Wikipedia]] since April 15. It is the first project that will be able to call [[f:Special:MyLanguage/Wikifunctions:Introduction|functions from Wikifunctions]] and integrate them in articles. A function is something that takes one or more inputs and transforms them into a desired output, such as adding up two numbers, converting miles into metres, calculating how much time has passed since an event, or declining a word into a case. Wikifunctions will allow users to do that through a simple call of [[f:Special:MyLanguage/Wikifunctions:Catalogue|a stable and global function]], rather than via a local template. [https://www.wikifunctions.org/wiki/Special:MyLanguage/Wikifunctions:Status_updates/2025-04-16] * A new type of lint error has been created: [[Special:LintErrors/empty-heading|{{int:linter-category-empty-heading}}]] ([[mw:Special:MyLanguage/Help:Lint errors/empty-heading|documentation]]). The [[mw:Special:MyLanguage/Help:Extension:Linter|Linter extension]]'s purpose is to identify wikitext patterns that must or can be fixed in pages and provide some guidance about what the problems are with those patterns and how to fix them. [https://phabricator.wikimedia.org/T368722] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:37}} community-submitted {{PLURAL:37|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Following its publication on HuggingFace, the "Structured Contents" dataset, developed by Wikimedia Enterprise, is [https://enterprise.wikimedia.com/blog/kaggle-dataset/ now also available on Kaggle]. This Beta initiative is focused on making Wikimedia data more machine-readable for high-volume reusers. They are releasing this beta version in a location that open dataset communities already use, in order to seek feedback, to help improve the product for a future wider release. You can read more about the overall [https://enterprise.wikimedia.com/blog/structured-contents-snapshot-api/#open-datasets Structured Contents project], and about the [https://enterprise.wikimedia.com/blog/structured-contents-wikipedia-infobox/ first release that's freely usable]. * There is no new MediaWiki version this week. '''Meetings and events''' * The Editing and Machine Learning Teams invite interested volunteers to a video meeting to discuss [[mw:Special:MyLanguage/Edit check/Peacock check|Peacock check]], which is the latest [[mw:Special:MyLanguage/Edit check|Edit check]] that will detect "peacock" or "overly-promotional" or "non-neutral" language whilst an editor is typing. Editors who work with newcomers, or help to fix this kind of writing, or are interested in how we use artificial intelligence in our projects are encouraged to attend. The [[mw:Special:MyLanguage/Editing team/Community Conversations#Next Conversation|meeting will be on April 28, 2025]] at [https://zonestamp.toolforge.org/1745863200 18:00–19:00 UTC] and hosted on Zoom. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/17|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W17"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:00, 21 April 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28578245 --> == Tech News: 2025-18 == <section begin="technews-2025-W18"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/18|Translations]] are available. '''Updates for editors''' * Event organizers who host collaborative activities on [[m:Special:MyLanguage/CampaignEvents/Deployment status#Global Deployment Plan|multiple wikis]], including Bengali, Japanese, and Korean Wikipedias, will have access to the [[mw:Special:MyLanguage/Extension:CampaignEvents|CampaignEvents extension]] this week. Also, admins in the Wikipedia where the extension is enabled will automatically be granted the event organizer right soon. They won't have to manually grant themselves the right before they can manage events as [[phab:T386861|requested by a community]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:19}} community-submitted {{PLURAL:19|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * The release of the next major version of [[mw:Special:MyLanguage/Codex|Codex]], the design system for Wikimedia, is scheduled for 29 April 2025. Technical editors will have access to the release by the week of 5 May 2025. This update will include a number of [[mw:Special:MyLanguage/Codex/Release_Timeline/2.0#Breaking_changes|breaking changes]] and minor [[mw:Special:MyLanguage/Codex/Release_Timeline/2.0#Visual_changes|visual changes]]. Instructions on handling the breaking and visual changes are documented on [[mw:Special:MyLanguage/Codex/Release Timeline/2.0#|this page]]. Pre-release testing is reported in [[phab:T386298|T386298]], with post-release issues tracked in [[phab:T392379|T392379]] and [[phab:T392390|T392390]]. * Users of [[wikitech:Special:MyLanguage/Help:Wiki_Replicas|Wiki Replicas]] will notice that the database views of <code dir="ltr">ipblocks</code>, <code dir="ltr">ipblocks_ipindex</code>, and <code dir="ltr">ipblocks_compat</code> are [[phab:T390767|now deprecated]]. Users can query the <code dir="ltr">[[mw:Special:MyLanguage/Manual:Block_table|block]]</code> and <code dir="ltr">[[mw:Special:MyLanguage/Manual:Block_target_table|block_target]]</code> new views that mirror the new tables in the production database instead. The deprecated views will be removed entirely from Wiki Replicas in June, 2025. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.27|MediaWiki]] '''In depth''' * The latest quarterly [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2025/April|Language and Internationalization Newsletter]] is now available. This edition includes an overview of the improved [https://test.wikipedia.org/w/index.php?title=Special:ContentTranslation&campaign=contributionsmenu&to=es&filter-type=automatic&filter-id=previous-edits&active-list=suggestions&from=en#/ Content Translation Dashboard Tool], [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2025/April#Language Support for New and Existing Languages|support for new languages]], [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2025/April#Wiki Loves Ramadan Articles Made In Content Translation Mobile Workflow|highlights from the Wiki Loves Ramadan campaign]], [[m:Special:MyLanguage/Research:Languages Onboarding Experiment 2024 - Executive Summary|results from the Language Onboarding Experiment]], an analysis of topic diversity in articles, and information on upcoming community meetings and events. '''Meetings and events''' * The [[Special:MyLanguage/Grants:Knowledge_Sharing/Connect/Calendar|Let's Connect Learning Clinic]] will take place on [https://zonestamp.toolforge.org/1745937000 April 29 at 14:30 UTC]. This edition will focus on "Understanding and Navigating Conflict in Wikimedia Projects". You can [[m:Special:MyLanguage/Event:Learning Clinic %E2%80%93 Understanding and Navigating Conflict in Wikimedia Projects (Part_1)|register now]] to attend. * The [[mw:Special:MyLanguage/Wikimedia Hackathon 2025|2025 Wikimedia Hackathon]], which brings the global technical community together to connect, brainstorm, and hack existing projects, will take place from May 2 to 4th, 2025, at Istanbul, Turkey. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/18|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W18"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:31, 28 April 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28585685 --> == Tech News: 2025-19 == <section begin="technews-2025-W19"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/19|Translations]] are available. '''Weekly highlight''' * The Wikimedia Foundation has shared the latest draft update to their [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026|annual plan]] for next year (July 2025–June 2026). This includes an [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026|executive summary]] (also on [[diffblog:2025/04/25/sharing-the-wikimedia-foundations-2025-2026-draft-annual-plan/|Diff]]), details about the three main [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Goals|goals]] ([[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Product & Technology OKRs|Infrastructure]], [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Goals/Volunteer Support|Volunteer Support]], and [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Goals/Effectiveness|Effectiveness]]), [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Global Trends|global trends]], and the [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Budget Overview|budget]] and [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026/Financial Model|financial model]]. Feedback and questions are welcome on the [[m:Talk:Wikimedia Foundation Annual Plan/2025-2026|talk page]] until the end of May. '''Updates for editors''' * For wikis that have the [[m:Special:MyLanguage/CampaignEvents/Deployment status|CampaignEvents extension enabled]], two new feature improvements have been released: ** Admins can now choose which namespaces are permitted for [[m:Special:MyLanguage/Event Center/Registration|Event Registration]] via [[mw:Special:MyLanguage/Community Configuration|Community Configuration]] ([[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Registration/Permitted namespaces|documentation]]). The default setup is for event registration to be permitted in the Event namespace, but other namespaces (such as the project namespace or WikiProject namespace) can now be added. With this change, communities like WikiProjects can now more easily use Event Registration for their collaborative activities. ** Editors can now [[mw:Special:MyLanguage/Transclusion|transclude]] the Collaboration List on a wiki page ([[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Collaboration list/Transclusion|documentation]]). The Collaboration List is an automated list of events and WikiProjects on the wikis, accessed via {{#special:AllEvents}} ([[w:en:Special:AllEvents|example]]). Now, the Collaboration List can be added to all sorts of wiki pages, such as: a wiki mainpage, a WikiProject page, an affiliate page, an event page, or even a user page. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Developers who use the <code dir=ltr>moment</code> library in gadgets and user scripts should revise their code to use alternatives like the <code dir=ltr>Intl</code> library or the new <code dir=ltr>mediawiki.DateFormatter</code> library. The <code dir=ltr>moment</code> library has been deprecated and will begin to log messages in the developer console. You can see a global search for current uses, and [[phab:T392532|ask related questions in this Phabricator task]]. * Developers who maintain a tool that queries the Wikidata term store tables (<code dir=ltr style="white-space: nowrap;">wbt_*</code>) need to update their code to connect to a separate database cluster. These tables are being split into a separate database cluster. Tools that query those tables via the wiki replicas must be adapted to connect to the new cluster instead. [[wikitech:News/2025 Wikidata term store database split|Documentation and related links are available]]. [https://phabricator.wikimedia.org/T390954] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.44/wmf.28|MediaWiki]] '''In depth''' * The latest [[mw:Special:MyLanguage/Extension:Chart/Project/Updates|Chart Project newsletter]] is available. It includes updates on preparing to expand the deployment to additional wikis as soon as this week (starting May 6) and scaling up over the following weeks, plus exploring filtering and transforming source data. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/19|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W19"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:14, 6 May 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28665011 --> == Tech News: 2025-20 == <section begin="technews-2025-W20"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/20|Translations]] are available. '''Weekly highlight''' * The [[m:Special:MyLanguage/Wikimedia URL Shortener|"Get shortened URL"]] link on the sidebar now includes a [[phab:T393309|QR code]]. Wikimedia site users can now use it by scanning or downloading it to quickly share and access shared content from Wikimedia sites, conveniently. '''Updates for editors''' * The Wikimedia Foundation is working on a system called [[m:Edge Uniques|Edge Uniques]], which will enable [[w:en:A/B testing|A/B testing]], help protect against [[w:en:Denial-of-service attack|distributed denial-of-service attacks]] (DDoS attacks), and make it easier to understand how many visitors the Wikimedia sites have. This is to help more efficiently build tools which help readers, and make it easier for readers to find what they are looking for. Tech News has [[m:Special:MyLanguage/Tech/News/2025/16|previously written about this]]. The deployment will be gradual. Some might see the Edge Uniques cookie the week of 19 May. You can discuss this on the [[m:Talk:Edge Uniques|talk page]]. * Starting May 19, 2025, Event organisers in wikis with the [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents extension]] enabled can use [[m:Special:MyLanguage/Event Center/Registration|Event Registration]] in the project namespace (e.g., Wikipedia namespace, Wikidata namespace). With this change, communities don't need admins to use the feature. However, wikis that don't want this change can remove and add the permitted namespaces at [[Special:CommunityConfiguration/CampaignEvents]]. * The Wikipedia project now has a {{int:project-localized-name-group-wikipedia/en}} in [[d:Q36720|Nupe]] ([[w:nup:|<code>w:nup:</code>]]). This is a language primarily spoken in the North Central region of Nigeria. Speakers of this language are invited to contribute to [[w:nup:Tatacin feregi|new Wikipedia]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Developers can now access pre-parsed Dutch Wikipedia, amongst others (English, German, French, Spanish, Italian, and Portuguese) through the [https://enterprise.wikimedia.com/docs/snapshot/#structured-contents-snapshot-bundle-info-beta Structured Contents snapshots (beta)]. The content includes parsed Wikipedia abstracts, descriptions, main images, infoboxes, article sections, and references. * The <code dir="ltr">/page/data-parsoid</code> REST API endpoint is no longer in use and will be deprecated. It is [[phab:T393557|scheduled to be turned off]] on June 7, 2025. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.1|MediaWiki]] '''In depth''' * The [https://wikitech.wikimedia.org/wiki/News/2025_Cloud_VPS_VXLAN_IPv6_migration IPv6 support] is a newly introduced Cloud virtual network that significantly boosts Wikimedia platforms' scalability, security, and readiness for the future. If you are a technical contributor eager to learn more, check out [https://techblog.wikimedia.org/2025/05/06/wikimedia-cloud-vps-ipv6-support/ this blog post] for an in-depth look at the journey to IPv6. '''Meetings and events''' * The 2nd edition of 2025 of [[m:Special:MyLanguage/Afrika Baraza|Afrika Baraza]], a virtual platform for African Wikimedians to connect, will take place on [https://zonestamp.toolforge.org/1747328400 May 15 at 17:00 UTC]. This edition will focus on discussions regarding [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2025-2026|Wikimedia Annual planning and progress]]. * The [[m:Special:MyLanguage/MENA Connect Community Call|MENA Connect Community Call]], a virtual meeting for [[w:en:Middle East and North Africa|MENA]] Wikimedians to connect, will take place on [https://zonestamp.toolforge.org/1747501200 May 17 at 17:00 UTC]. You can [[m:Event:MENA Connect (Wiki_Diwan) APP Call|register now]] to attend. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/20|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W20"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:37, 12 May 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28714188 --> == Tech News: 2025-21 == <section begin="technews-2025-W21"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/21|Translations]] are available. '''Weekly highlight''' * The Editing Team and the Machine Learning Team are working on a new check for newcomers: [[mw:Edit check/Peacock check|Peacock check]]. Using a prediction model, this check will encourage editors to improve the tone of their edits, using artificial intelligence. We invite volunteers to review the first version of the Peacock language model for the following languages: Arabic, Spanish, Portuguese, English, and Japanese. Users from these wikis interested in reviewing this model are [[mw:Edit check/Peacock check/model test|invited to sign up at MediaWiki.org]]. The deadline to sign up is on May 23, which will be the start date of the test. '''Updates for editors''' * From May 20, 2025, [[m:Special:MyLanguage/Oversight policy|oversighters]] and [[m:Special:MyLanguage/Meta:CheckUsers|checkusers]] will need to have their accounts secured with two-factor authentication (2FA) to be able to use their advanced rights. All users who belong to these two groups and do not have 2FA enabled have been informed. In the future, this requirement may be extended to other users with advanced rights. [[m:Special:MyLanguage/Mandatory two-factor authentication for users with some extended rights|Learn more]]. * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] [[m:Special:MyLanguage/Community Wishlist Survey 2023/Multiblocks|Multiblocks]] will begin mass deployment by the end of the month: all non-Wikipedia projects plus Catalan Wikipedia will adopt Multiblocks in the week of May 26, while all other Wikipedias will adopt it in the week of June 2. Please [[m:Talk:Community Wishlist Survey 2023/Multiblocks|contact the team]] if you have concerns. Administrators can test the new user interface now on your own wiki by browsing to [{{fullurl:Special:Block|usecodex=1}} {{#special:Block}}?usecodex=1], and can test the full multiblocks functionality [[testwiki:Special:Block|on testwiki]]. Multiblocks is the feature that makes it possible for administrators to impose different types of blocks on the same user at the same time. See the [[mw:Special:MyLanguage/Help:Manage blocks|help page]] for more information. [https://phabricator.wikimedia.org/T377121] * Later this week, the [[{{#special:SpecialPages}}]] listing of almost all special pages will be updated with a new design. This page has been [[phab:T219543|redesigned]] to improve the user experience in a few ways, including: The ability to search for names and aliases of the special pages, sorting, more visible marking of restricted special pages, and a more mobile-friendly look. The new version can be [https://meta.wikimedia.beta.wmflabs.org/wiki/Special:SpecialPages previewed] at Beta Cluster now, and feedback shared in the task. [https://phabricator.wikimedia.org/T219543] * The [[mw:Special:MyLanguage/Extension:Chart|Chart extension]] is being enabled on more wikis. For a detailed list of when the extension will be enabled on your wiki, please read the [[mw:Special:MyLanguage/Extension:Chart/Project#Deployment Timeline|deployment timeline]]. * [[f:Special:MyLanguage/Wikifunctions:Main Page|Wikifunctions]] will be deployed on May 27 on five Wiktionaries: [[wikt:ha:|Hausa]], [[wikt:ig:|Igbo]], [[wikt:bn:|Bengali]], [[wikt:ml:|Malayalam]], and [[wikt:dv:|Dhivehi/Maldivian]]. This is the second batch of deployment planned for the project. After deployment, the projects will be able to call [[f:Special:MyLanguage/Wikifunctions:Introduction|functions from Wikifunctions]] and integrate them in their pages. A function is something that takes one or more inputs and transforms them into a desired output, such as adding up two numbers, converting miles into metres, calculating how much time has passed since an event, or declining a word into a case. Wikifunctions will allow users to do that through a simple call of [[f:Special:MyLanguage/Wikifunctions:Catalogue|a stable and global function]], rather than via a local template. * Later this week, the Wikimedia Foundation will publish a hub for [[diffblog:2024/07/09/on-the-value-of-experimentation/|experiments]]. This is to showcase and get user feedback on product experiments. The experiments help the Wikimedia movement [[diffblog:2023/07/13/exploring-paths-for-the-future-of-free-knowledge-new-wikipedia-chatgpt-plugin-leveraging-rich-media-social-apps-and-other-experiments/|understand new users]], how they interact with the internet and how it could affect the Wikimedia movement. Some examples are [[m:Special:MyLanguage/Future Audiences/Generated Video|generated video]], the [[m:Special:MyLanguage/Future Audiences/Roblox game|Wikipedia Roblox speedrun game]] and [[m:Special:MyLanguage/Future Audiences/Discord bot|the Discord bot]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:29}} community-submitted {{PLURAL:29|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, there was a bug with creating an account using the API, which has now been fixed. [https://phabricator.wikimedia.org/T390751] '''Updates for technical contributors''' * Gadgets and user scripts that interact with [[{{#special:Block}}]] may need to be updated to work with the new [[mw:Special:MyLanguage/Help:Manage blocks|manage blocks interface]]. Please review the [[mw:Help:Manage blocks/Developers|developer guide]] for more information. If you need help or are unable to adapt your script to the new interface, please let the team know on the [[mw:Help talk:Manage blocks/Developers|talk page]]. [https://phabricator.wikimedia.org/T377121] * The <code dir=ltr>mw.title</code> object allows you to get information about a specific wiki page in the [[w:en:Wikipedia:Lua|Lua]] programming language. Starting this week, a new property will be added to the object, named <code dir=ltr>isDisambiguationPage</code>. This property allows you to check if a page is a disambiguation page, without the need to write a custom function. [https://phabricator.wikimedia.org/T71441] * [[File:Octicons-tools.svg|15px|link=|class=skin-invert|Advanced item]] User script developers can use a [[toolforge:gitlab-content|new reverse proxy tool]] to load javascript and css from [[gitlab:|gitlab.wikimedia.org]] with <code dir=ltr>mw.loader.load</code>. The tool's author hopes this will enable collaborative development workflows for user scripts including linting, unit tests, code generation, and code review on <bdi lang="zxx" dir="ltr">gitlab.wikimedia.org</bdi> without a separate copy-and-paste step to publish scripts to a Wikimedia wiki for integration and acceptance testing. See [[wikitech:Tool:Gitlab-content|Tool:Gitlab-content on Wikitech]] for more information. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.2|MediaWiki]] '''Meetings and events''' * The 12th edition of [[m:Special:MyLanguage/Wiki Workshop 2025|Wiki Workshop 2025]], a forum that brings together researchers that explore all aspects of Wikimedia projects, will be held virtually on 21-22 May. Researchers can [https://pretix.eu/wikimedia/wikiworkshop2025/ register now]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/21|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W21"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:12, 19 May 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28724712 --> == Tech News: 2025-22 == <section begin="technews-2025-W22"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/22|Translations]] are available. '''Weekly highlight''' * A community-wide discussion about a very delicate issue for the development of [[m:Special:MyLanguage/Abstract Wikipedia|Abstract Wikipedia]] is now open on Meta: where to store the abstract content that will be developed through functions from Wikifunctions and data from Wikidata. The discussion is open until June 12 at [[m:Special:MyLanguage/Abstract Wikipedia/Location of Abstract Content|Abstract Wikipedia/Location of Abstract Content]], and every opinion is welcomed. The decision will be made and communicated after the consultation period by the Foundation. '''Updates for editors''' * Since last week, on all wikis except [[phab:T388604|the largest 20]], people using the mobile visual editor will have [[phab:T385851|additional tools in the menu bar]], accessed using the new <code>+</code> toolbar button. To start, the new menu will include options to add: citations, hieroglyphs, and code blocks. Deployment to the remaining wikis is [[phab:T388605|scheduled]] to happen in June. * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] The <code dir=ltr>[[mw:Special:MyLanguage/Help:Extension:ParserFunctions##ifexist|#ifexist]]</code> parser function will no longer register a link to its target page. This will improve the usefulness of [[{{#special:WantedPages}}]], which will eventually only list pages that are the target of an actual red link. This change will happen gradually as the source pages are updated. [https://phabricator.wikimedia.org/T14019] * This week, the Moderator Tools team will launch [[mw:Special:MyLanguage/2025 RecentChanges Language Agnostic Revert Risk Filtering|a new filter to Recent Changes]], starting at Indonesian Wikipedia. This new filter highlights edits that are likely to be reverted. The goal is to help Recent Changes patrollers identify potentially problematic edits. Other wikis will benefit from this filter in the future. * Upon clicking an empty search bar, logged-out users will see suggestions of articles for further reading. The feature will be available on both desktop and mobile. Readers of Catalan, Hebrew, and Italian Wikipedias and some sister projects will receive the change between May 21 and mid-June. Readers of other wikis will receive the change later. The goal is to encourage users to read the wikis more. [[mw:Special:MyLanguage/Reading/Web/Content Discovery Experiments/Search Suggestions|Learn more]]. * Some users of the Wikipedia Android app can use a new feature for readers, [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/TrivaGame|WikiGames]], a daily trivia game based on real historical events. The release has started as an A/B test, available to 50% of users in the following languages: English, French, Portuguese, Russian, Spanish, Arabic, Chinese, and Turkish. * The [[mw:Special:MyLanguage/Extension:Newsletter|Newsletter extension]] that is available on MediaWiki.org allows the creation of [[mw:Special:Newsletters|various newsletters]] for global users. The extension can now publish new issues as section links on an existing page, instead of requiring a new page for each issue. [https://phabricator.wikimedia.org/T393844] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:32}} community-submitted {{PLURAL:32|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * The previously deprecated <code dir=ltr>[[mw:Special:MyLanguage/Manual:Ipblocks table|ipblocks]]</code> views in [[wikitech:Help:Wiki Replicas|Wiki Replicas]] will be removed in the beginning of June. Users are encouraged to query the new <code dir=ltr>[[mw:Special:MyLanguage/Manual:Block table|block]]</code> and <code dir=ltr>[[mw:Special:MyLanguage/Manual:Block target table|block_target]]</code> views instead. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.3|MediaWiki]] '''Meetings and events''' * [[d:Special:MyLanguage/Event:Wikidata and Sister Projects|Wikidata and Sister Projects]] is a multi-day online event that will focus on how Wikidata is integrated to Wikipedia and the other Wikimedia projects. The event runs from May 29 – June 1. You can [[d:Special:MyLanguage/Event:Wikidata and Sister Projects#Sessions|read the Program schedule]] and [[d:Special:RegisterForEvent/1291|register]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/22|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W22"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:04, 26 May 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28788673 --> == Tech News: 2025-23 == <section begin="technews-2025-W23"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/23|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Extension:Chart|Chart extension]] is now available on all Wikimedia wikis. Editors can use this new extension to create interactive data visualizations like bar, line, area, and pie charts. Charts are designed to replace many of the uses of the legacy [[mw:Special:MyLanguage/Extension:Graph|Graph extension]]. '''Updates for editors''' * It is now easier to configure automatic citations for your wiki within the visual editor's [[mw:Special:MyLanguage/Citoid/Enabling Citoid on your wiki|citation generator]]. Administrators can now set a default template by using the <code dir=ltr>_default</code> key in the local <bdi lang="en" dir="ltr">[[MediaWiki:Citoid-template-type-map.json]]</bdi> page ([[mw:Special:Diff/6969653/7646386|example diff]]). Setting this default will also help to future-proof your existing configurations when [[phab:T347823|new item types]] are added in the future. You can still set templates for individual item types as they will be preferred to the default template. [https://phabricator.wikimedia.org/T384709] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Starting the week of June 2, bots logging in using <code dir=ltr>action=login</code> or <code dir=ltr>action=clientlogin</code> will fail more often. This is because of stronger protections against suspicious logins. Bots using [[mw:Special:MyLanguage/Manual:Bot passwords|bot passwords]] or using a loginless authentication method such as [[mw:Special:MyLanguage/OAuth/Owner-only consumers|OAuth]] are not affected. If your bot is not using one of those, you should update it; using <code dir=ltr>action=login</code> without a bot password was deprecated [[listarchive:list/wikitech-l@lists.wikimedia.org/message/3EEMN7VQX5G7WMQI5K2GP5JC2336DPTD/|in 2016]]. For most bots, this only requires changing what password the bot uses. [https://phabricator.wikimedia.org/T395205] * From this week, Wikimedia wikis will allow ES2017 features in JavaScript code for official code, gadgets, and user scripts. The most visible feature of ES2017 is <bdi lang="zxx" dir="ltr"><code>async</code>/<code>await</code></bdi> syntax, allowing for easier-to-read code. Until this week, the platform only allowed up to ES2016, and a few months before that, up to ES2015. [https://phabricator.wikimedia.org/T381537] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.4|MediaWiki]] '''Meetings and events''' * Scholarship applications to participate in the [[m:Special:MyLanguage/GLAM Wiki 2025|GLAM Wiki Conference 2025]] are now open. The conference will take place from 30 October to 1 November, in Lisbon, Portugal. GLAM contributors who lack the means to support their participation can [[m:Special:MyLanguage/GLAM Wiki 2025/Scholarships|apply here]]. Scholarship applications close on June 7th. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/23|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W23"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:55, 2 June 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28819186 --> == Tech News: 2025-24 == <section begin="technews-2025-W24"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/24|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Trust and Safety Product|Trust and Safety Product team]] is finalizing work needed to roll out [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] on large Wikipedias later this month. The team has worked with stewards and other users with extended rights to predict and address many use cases that may arise on larger wikis, so that community members can continue to effectively moderate and patrol temporary accounts. This will be the second of three phases of deployment – the last one will take place in September at the earliest. For more information about the recent developments on the project, [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/Updates|see this update]]. If you have any comments or questions, write on the [[mw:Talk:Trust and Safety Product/Temporary Accounts|talk page]], and [[m:Event:CEE Catch up Nr. 10 (June 2025)|join a CEE Catch Up]] this Tuesday. '''Updates for editors''' * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] The [[mw:Special:MyLanguage/Help:Watchlist expiry|watchlist expiry]] feature allows editors to watch pages for a limited period of time. After that period, the page is automatically removed from your watchlist. Starting this week, you can set a preference for the default period of time to watch pages. The [[Special:Preferences#mw-prefsection-watchlist-pageswatchlist|preferences]] also allow you to set different default watch periods for editing existing pages, pages you create, and when using rollback. [https://phabricator.wikimedia.org/T265716] [[File:Talk pages default look (April 2023).jpg|thumb|alt=Screenshot of the visual improvements made on talk pages|Example of a talk page with the new design, in French.]] * The appearance of talk pages will change at almost all Wikipedias ([[m:Special:MyLanguage/Tech/News/2024/19|some]] have already received this design change, [[phab:T379264|a few]] will get these changes later). You can read details about the changes [[diffblog:2024/05/02/making-talk-pages-better-for-everyone/|on ''Diff'']]. It is possible to opt out of these changes [[Special:Preferences#mw-prefsection-editing-discussion|in user preferences]] ("{{int:discussiontools-preference-visualenhancements}}"). [https://phabricator.wikimedia.org/T319146][https://phabricator.wikimedia.org/T392121] * Users with specific extended rights (including administrators, bureaucrats, checkusers, oversighters, and stewards) can now have IP addresses of all temporary accounts [[phab:T358853|revealed automatically]] during time-limited periods where they need to combat high-speed account-hopping vandalism. This feature was requested by stewards. [https://phabricator.wikimedia.org/T386492] * This week, the Moderator Tools and Machine Learning teams will continue the rollout of [[mw:Special:MyLanguage/2025 RecentChanges Language Agnostic Revert Risk Filtering|a new filter to Recent Changes]], releasing it to several more Wikipedias. This filter utilizes the Revert Risk model, which was created by the Research team, to highlight edits that are likely to be reverted and help Recent Changes patrollers identify potentially problematic contributions. The feature will be rolled out to the following Wikipedias: {{int:project-localized-name-afwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-bnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cywiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hawwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-iswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kkwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-simplewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-trwiki/en}}. The rollout will continue in the coming weeks to include [[mw:Special:MyLanguage/2025 RecentChanges Language Agnostic Revert Risk Filtering|the rest of the Wikipedias in this project]]. [https://phabricator.wikimedia.org/T391964] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * AbuseFilter editors active on Meta-Wiki and large Wikipedias are kindly asked to update AbuseFilter to make it compatible with temporary accounts. A link to the instructions and the private lists of filters needing verification are [[phab:T369611|available on Phabricator]]. * Lua modules now have access to the name of a page's associated thumbnail image, and on [https://gerrit.wikimedia.org/g/operations/mediawiki-config/+/2e4ab14aa15bb95568f9c07dd777065901eb2126/wmf-config/InitialiseSettings.php#10849 some wikis] to the WikiProject assessment information. This is possible using two new properties on [[mw:Special:MyLanguage/Extension:Scribunto/Lua reference manual#added-by-extensions|mw.title objects]], named <code dir=ltr>pageImage</code> and <code dir=ltr>pageAssessments</code>. [https://phabricator.wikimedia.org/T131911][https://phabricator.wikimedia.org/T380122] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.5|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/24|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W24"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:16, 10 June 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28846858 --> == Tech News: 2025-25 == <section begin="technews-2025-W25"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/25|Translations]] are available. '''Updates for editors''' * You can [https://wikimediafoundation.limesurvey.net/359761?lang=en nominate your favorite tools] for the sixth edition of the [[m:Special:MyLanguage/Coolest Tool Award|Coolest Tool Award]]. Nominations are anonymous and will be open until June 25. You can re-use the survey to nominate multiple tools. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:33}} community-submitted {{PLURAL:33|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.6|MediaWiki]] '''In depth''' * Foundation staff and technical volunteers use Wikimedia APIs to build the tools, applications, features, and integrations that enhance user experiences. Over the coming years, the MediaWiki Interfaces team will be investing in Wikimedia web (HTTP) APIs to better serve technical volunteer needs and protect Wikimedia infrastructure from potential abuse. You can [https://techblog.wikimedia.org/2025/06/12/apis-as-a-product-investing-in-the-current-and-next-generation-of-technical-contributors/ read more about their plans to evolve the APIs in this Techblog post]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/25|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W25"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:38, 16 June 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28870688 --> == Tech News: 2025-26 == <section begin="technews-2025-W26"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/26|Translations]] are available. '''Weekly highlight''' * This week, the Moderator Tools and Machine Learning teams will continue the rollout of [[mw:Special:MyLanguage/2025 RecentChanges Language Agnostic Revert Risk Filtering|a new filter to Recent Changes]], releasing it to the third and last batch of Wikipedias. This filter utilizes the Revert Risk model, which was created by the Research team, to highlight edits that are likely to be reverted and help Recent Changes patrollers identify potentially problematic contributions. The feature will be rolled out to the following Wikipedias: {{int:project-localized-name-azwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-lawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mkwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-mrwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nnwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-pawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-swwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-tlwiki/en}}. The rollout will continue in the coming weeks to include [[mw:Special:MyLanguage/2025 RecentChanges Language Agnostic Revert Risk Filtering|the rest of the Wikipedias in this project]]. [https://phabricator.wikimedia.org/T391964] '''Updates for editors''' * Last week, [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] were rolled out on Czech, Korean, and Turkish Wikipedias. This and next week, deployments on larger Wikipedias will follow. [[mw:Talk:Trust and Safety Product/Temporary Accounts|Share your thoughts]] about the project. [https://phabricator.wikimedia.org/T340001] * Later this week, the Editing team will release [[mw:Special:MyLanguage/Help:Edit check#Multi check|Multi Check]] to all Wikipedias (except English Wikipedia). This feature shows multiple [[mw:Special:MyLanguage/Help:Edit check#Reference check|Reference checks]] within the editing experience. This encourages users to add citations when they add multiple new paragraphs to a Wikipedia article. This feature was previously available as an A/B test. [https://analytics.wikimedia.org/published/reports/editing/multi_check_ab_test_report_final.html#summary-of-results The test shows] that users who are shown multiple checks are 1.3 times more likely to add a reference to their edit, and their edit is less likely to be reverted (-34.7%). [https://phabricator.wikimedia.org/T395519] * A few pages need to be renamed due to software updates and to match more recent Unicode standards. All of these changes are related to title-casing changes. Approximately 71 pages and 3 files will be renamed, across 15 wikis; the complete list is in [[phab:T396903|the task]]. The developers will rename these pages next week, and they will fix redirects and embedded file links a few minutes later via a system settings update. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:24}} community-submitted {{PLURAL:24|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was fixed that had caused pages to scroll upwards when text near the top was selected. [https://phabricator.wikimedia.org/T364023] '''Updates for technical contributors''' * Editors can now use Lua modules to filter and transform tabular data for use with [[mw:Special:MyLanguage/Extension:Chart|Extension:Chart]]. This can be used for things like selecting a subset of rows or columns from the source data, converting between units, statistical processing, and many other useful transformations. [[mw:Special:MyLanguage/Extension:Chart/Transforms|Information on how to use transforms is available]]. [https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:Chart/Project/Updates] * The <code dir=ltr>all_links</code> variable in [[Special:AbuseFilter|AbuseFilter]] is now renamed to <code dir=ltr>new_links</code> for consistency with other variables. Old usages will still continue to work. [https://phabricator.wikimedia.org/T391811] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.7|MediaWiki]] '''In depth''' * The latest quarterly [[mw:Special:MyLanguage/Growth/Newsletters/34|Growth newsletter]] is available. It includes: the recent updates for the "Add a Link" Task, two new Newcomer Engagement Features, and updates to Community Configuration. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/26|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W26"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:21, 23 June 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28870688 --> == Tech News: 2025-27 == <section begin="technews-2025-W27"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/27|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents extension]] has been enabled on all Wikipedias. The extension makes it easier to organize and participate in collaborative activities, like edit-a-thons and WikiProjects, on the wikis. The extension has three features: [[m:Special:MyLanguage/Event Center/Registration|Event Registration]], [[m:Special:MyLanguage/CampaignEvents/Collaboration list|Collaboration List]], and [[m:Campaigns/Foundation Product Team/Invitation list|Invitation List]]. To request the extension for your wiki, visit the [[m:Special:MyLanguage/CampaignEvents/Deployment status#How to Request the CampaignEvents Extension for your wiki|Deployment information page]]. '''Updates for editors''' * AbuseFilter maintainers can now [[mw:Special:MyLanguage/Extension:IPReputation/AbuseFilter variables|match against IP reputation data]] in [[mw:Special:MyLanguage/Extension:AbuseFilter|AbuseFilters]]. IP reputation data is information about the proxies and VPNs associated with the user's IP address. This data is not shown publicly and is not generated for actions performed by registered accounts. [https://phabricator.wikimedia.org/T354599] * Hidden content that is within [[mw:Special:MyLanguage/Manual:Collapsible elements|collapsible parts of wikipages]] will now be revealed when someone searches the page using the web browser's "Find in page" function (Ctrl+F or ⌘F) in supporting browsers. [https://phabricator.wikimedia.org/T327893][https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes/hidden#browser_compatibility] * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] A new feature, called [[mw:Special:MyLanguage/Help:TemplateData/Template discovery|Favourite Templates]], will be deployed later this week on all projects (except English Wikipedia, which will receive the feature next week), following a piloting phase on Polish and Arabic Wikipedia, and Italian and English Wikisource. The feature will provide a better way for new and experienced contributors to recall and discover templates via the template dialog, by allowing users to put templates on a special "favourite list". The feature works with both the visual editor and the wikitext editor. The feature is a [[m:Special:MyLanguage/Community Wishlist/Focus areas/Template recall and discovery|community wishlist focus area]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was fixed that had caused some Notifications to be sent multiple times. [https://phabricator.wikimedia.org/T397103] '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.8|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/27|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W27"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:40, 30 June 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28917415 --> == Tech News: 2025-28 == <section begin="technews-2025-W28"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/28|Translations]] are available. '''Weekly highlight''' * [[mw:Special:MyLanguage/Help:Temporary accounts|Temporary accounts]] have been rolled out on 18 large and medium-sized Wikipedias, including German, Japanese, French, and Chinese. Now, about 1/3 of all logged-out activity across wikis is coming from temporary accounts. Users involved in patrolling may be interested in two new documentation pages: [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/Access to IP|Access to IP]], explaining everything related to access to temporary account IP addresses, and [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts/Repository|Repository]] with a list of new gadgets and user scripts. '''Updates for editors''' * Anyone can play an experimental new game, [[mw:Special:MyLanguage/New Engagement Experiments/WikiRun|WikiRun]], that lets you race through Wikipedia by clicking from one article to another, aiming to reach a target page in as few steps and in as little time as possible. The project's goal is to explore new ways of engaging readers. [https://wikirun-game.toolforge.org/ Try playing the game] and let the team know what you think [[mw:Talk:New Engagement Experiments/WikiRun|on the talk page]]. * Users of the Wikipedia Android app in some languages can now play the new [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/TrivaGame|trivia game]]. ''Which came first?'' is a simple history game where you guess which of two events happened earlier on today's date. It was previously available as an A/B test. It is now available to all users in English, German, French, Spanish, Portuguese, Russian, Arabic, Turkish, and Chinese. The goal of the feature is to help engage with new generations of readers. [https://meta.wikimedia.org/wiki/Special:MyLanguage/Tech/News/2025/22] * Users of the iOS Wikipedia App in some languages may see a new tabbed browsing feature that enables you to open multiple tabs while reading. This feature makes it easier to explore related topics and switch between articles. The A/B test is currently running in Arabic, English, and Japanese in selected regions. More details are available on the [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/Tabbed Browsing (Tabs)|Tabbed Browsing project page]]. * Bureaucrats on Wikimedia wikis can now use [[{{#special:VerifyOATHForUser}}]] to check if users have enabled [[mw:Special:MyLanguage/Help:Two-factor authentication|two-factor authentication]]. [https://phabricator.wikimedia.org/T265726] * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] A new feature related to [[m:Special:MyLanguage/Community Wishlist/Focus areas/Template recall and discovery|Template Recall and Discovery]] will be deployed later this week to all Wikimedia projects: a [[mw:Special:MyLanguage/Help:TemplateData/Template discovery#Template categories|template category browser]] will be introduced to assist users in finding templates to put in their “favourite” list. The browser will allow users to browse a list of templates which have been organised into a given category tree. The feature has been requested by the community [[m:Special:MyLanguage/Community Wishlist/Wishes/Select templates by categories|through the Community Wishlist]]. * It is now possible to access watchlist preferences from the watchlist page. Also the redundant button to edit the watchlist has been removed. [https://www.mediawiki.org/wiki/Moderator_Tools/Watchlist] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * As part of [[mw:MediaWiki_1.44|MediaWiki 1.44]] there is now a unified built-in Notifications system that makes it easier for developers to send, manage, and customize notifications. Check out the updated documentation at [[mw:Manual:Notifications|Manual:Notifications]], information about migration in [[phab:T388663|T388663]] and details on deprecated hooks in [[phab:T389624|T389624]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.9|MediaWiki]] '''Meetings and events''' * [[d:Special:MyLanguage/Event:WikidataCon 2025|WikidataCon 2025]], the conference dedicated to Wikidata is now open for [https://pretalx.com/wikidatacon-2025/cfp session proposals] and for [[d:Special:RegisterForEvent/1340|registration]]. This year's event will be held online from October 31 – November 02 and will explore on the theme of "Connecting People through Linked Open Data". '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/28|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W28"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:05, 8 July 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28930584 --> == Tech News: 2025-29 == <section begin="technews-2025-W29"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/29|Translations]] are available. '''Updates for editors''' * [[mw:Special:MyLanguage/Help:TemplateData/Template discovery#Featured templates|Featured templates]], a new feature related to [[m:Special:MyLanguage/Community Wishlist/Focus areas/Template recall and discovery|Template Recall and Discovery]] will be deployed this week to all Wikimedia projects: With this feature, editors will be able to quickly access a list of templates that are likely to be useful. These templates will be displayed in a list, under the "featured" tab of the template discovery interface. Administrators can define the list via the Community Configuration interface. The feature fulfills a request by the community [[m:Special:MyLanguage/Community Wishlist/Wishes/Easy access Templates|through the Community Wishlist]]. [https://phabricator.wikimedia.org/T367428][https://phabricator.wikimedia.org/T392896] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the request to add Malayalam fonts in the [[oldWikisource:Special:MyLanguage/Wikisource:WS Export|Wikisource Book Export Tool]] was resolved and now, the rendering of Malayalam letters in exported Wikisource books are accurate. [https://phabricator.wikimedia.org/T374457] '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.10|MediaWiki]] '''In depth''' * Developers, designers, and all Wikimedians are invited to [https://phabricator.wikimedia.org/project/board/7953/ submit a project idea] for the Wikimania Hackathon 2025. Read [https://diff.wikimedia.org/2025/06/30/call-for-projects-wikimania-hackathon-2025-is-coming-to-nairobi/ this Diff blog post] for more details. '''Meetings and events''' * [[m:WikiIndaba conference 2025|WikiIndaba 2025]] scholarship application and program submission is open until 23:59 GMT on July 20. WikiIndaba is a regional conference for African Wikimedians both on the continent and in the diaspora to unite and grow together. Submit [https://docs.google.com/forms/d/e/1FAIpQLSdJTv68R1OPASXXDfpIl8EWiMLTM-TDwh6_5gNVvFuWccFZ2Q/viewform your scholarship application] and [https://ee.kobotoolbox.org/x/BI3omIfH program proposal] now! * [https://br.wikimedia.org/wiki/WikiCon_Brasil_2025 WikiCon Brasil 2025] will take place on July 19-20 in Salvador, Bahia, Brazil. The Brazilian community members are encouraged to register and attend! '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/29|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W29"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:09, 14 July 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=28980963 --> == Tech News: 2025-30 == <section begin="technews-2025-W30"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/30|Translations]] are available. '''Updates for editors''' * The Translation Suggestions feature in the [[mw:Special:MyLanguage/Content translation|Content Translation tool]] now has another level of article filters added to the "[https://en.wikipedia.org/w/index.php?title=Special:ContentTranslation&filter-type=automatic&filter-id=previous-edits&active-list=suggestions&from=en&to=fi#/ ... More]" category. Translators who use the Suggestions feature can now select and receive article suggestions that are customized to geographical locations of their interest using the new "{{int:Cx-sx-suggestions-filters-tab-regions}}" filter. [https://phabricator.wikimedia.org/T113257] * Administrators can now limit "Add a Link" to newcomers. The [[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|"Add a Link"]] Structured Task [[mw:Special:MyLanguage/Growth/Constructive activation experimentation#Enwiki A/B test & "Add a Link" Improvements (Wiki Experiences 1.2.11 & 1.2.16)|helps new account holders start editing]], but some communities have requested the ability to restrict it to its intended audience: newcomers. Administrators can configure this setting within the [[Special:CommunityConfiguration/GrowthSuggestedEdits|Community Configuration]] feature. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:29}} community-submitted {{PLURAL:29|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * For AbuseFilter editors on [[phab:T392144|some wikis]], it is now possible to filter edits based on the RevertRisk score of the edit being attempted. It is only populated if the action being evaluated is an edit. For more information, please see the [[mw:Special:MyLanguage/Extension:ORES/AbuseFilter variables#What variables are available for use|ORES/AbuseFilter variables]] documentation. * The [[mw:Special:MyLanguage/Beta Cluster|Beta Cluster]] wikis have [[listarchive:list/wikitech-l@lists.wikimedia.org/thread/YDABPV75LADRQCXMJAFWUP256N4EQ25B/|been moved]] from <code dir=ltr>beta.wmflabs.org</code> to <code dir=ltr>beta.wmcloud.org</code>. Users may need to update URLs in any tools, or in their password managers. Any related issues can be [[phab:T289318|reported in the task]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.11|MediaWiki]] '''Meetings and events''' * [[m:Special:MyLanguage/WikiCite 2025|WikiCite 2025]] will take place from 29–31 August, both online and in-person in Bern, Switzerland. The event's goals are to reconnect communities, institutions, and individuals working with open citations, bibliographic data, and the Wikidata/Wikibase ecosystem. Registration is open and the call for proposals will be announced soon. [https://lists.wikimedia.org/hyperkitty/list/wikidata@lists.wikimedia.org/message/KQZUG3ETKLBWPBYSB2YAWZIRPWHS24TG/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/30|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W30"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:42, 21 July 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29005283 --> == Tech News: 2025-31 == <section begin="technews-2025-W31"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/31|Translations]] are available. '''Weekly highlight''' * The Community Tech team will be focusing on wishes related to Watchlists and Recent Changes pages, over the next few months. They are looking for feedback. Please [[m:Special:MyLanguage/Community Wishlist/Updates#July 24, 2025: Watchlists and Recent Changes pages|read the latest update]], and if you have ideas, please [[m:Special:MyLanguage/Community Wishlist|submit a wish]] on the topic. '''Updates for editors''' * The Wikimedia Commons community has decided to block [[:mw:Special:MyLanguage/Upload dialog|cross-wiki uploads]] to Wikimedia Commons, for all users without autoconfirmed rights on that wiki, starting on August 16. This is because of [[:c:Commons:Cross-wiki media upload tool/History|widespread problems]] related to files that are uploaded by newcomers. Users who are affected by this will get an error message with a link to the less restrictive UploadWizard on Commons. Please help translating the [[:c:Special:MyLanguage/MediaWiki:Abusefilter-disallowed-cross-wiki-upload|message]] or give feedback on the message text. Please also update your local help pages to explain this restriction. [https://phabricator.wikimedia.org/T370598] * On wikis with temporary accounts enabled and Meta-Wiki, administrators may now set up a footer for the Special:Contributions pages of temporary accounts, similar to those which can be shown on IP and user-account pages. They may do it by creating the page named <code dir=ltr>MediaWiki:Sp-contributions-footer-temp</code>. [https://phabricator.wikimedia.org/T398347] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:21}} community-submitted {{PLURAL:21|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.12|MediaWiki]] '''Meetings and events''' * [[wmania:Special:MyLanguage/2025:Wikimania|Wikimania 2025]] will run from August 6–9. The [https://wikimedia.eventyay.com/talk/wikimania2025/schedule/ program is available] for you to plan which sessions you want to attend. Most sessions will be live-streamed, with exceptions for those that show the "no camera" icon. If you are joining online to watch live-streams and use the interactive features, please [[wmania:Special:MyLanguage/2025:Registration|register]] for a free virtual ticket. For example, you may be interested in technical sessions such as: ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/KFEFVG/ Temporary Accounts: Enhancing privacy for our unregistered editors] ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/TVCVAB/ Building a Sustainable Future for Wikimedia Contributors] ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/WTRQCJ/ A dozen visions for wikitext!] ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/8YKKP9/ Coordinate Across Stakeholders with the Product and Technology Advisory Council] * The [[mw:Special:MyLanguage/MediaWiki Users and Developers Conference Fall 2025|MediaWiki Users and Developers Conference, Fall 2025]] will be held 28–30 October 2025 in Hanover, Germany. This event is organized by and for the third-party MediaWiki community. You can propose sessions and register to attend. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W31"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:26, 29 July 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29051727 --> == Tech News: 2025-32 == <section begin="technews-2025-W32"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/32|Translations]] are available. '''Updates for editors''' * Editors can now enable the [[mw:Special:MyLanguage/Product Safety and Integrity/Anti-abuse signals/User Info|User Info card]]. This feature adds an icon next to usernames on history pages and similar user-contribution log pages. When you tap or click on the icon, it displays data related to that user account such as the number of edits, reverted edits, blocks, and more. It's part of a broader project to make it easier for moderators to evaluate account trustworthiness. The feature can be enabled in [[testwiki:Special:GlobalPreferences#mw-prefsection-rendering|your global preferences]], and later this week it will be available in local preferences. [https://phabricator.wikimedia.org/T386439] * Everybody is invited to share comments on [[m:Special:MyLanguage/CampaignEvents/Collaborative contributions|Collaborative Contributions]], a project recently launched by the [[m:Special:MyLanguage/Connection Team|Connection team]]. The project aims to create a new way to display the impact of collaborative editing activities (such as edit-a-thons, backlog drives, and WikiProjects) on the wikis. Post your comments on the [[m:Talk:CampaignEvents/Collaborative contributions|project talk page]]. [https://phabricator.wikimedia.org/T378035] * Administrators can now define the default block duration for temporary accounts. To do that, they need to create a page named <code dir=ltr>MediaWiki:Ipb-default-expiry-temporary-account</code> and use a value defined in <code dir=ltr>MediaWiki:Ipboptions</code>. This allows administrators to easily block temporary accounts for 90 days, which is functionally equivalent to an indefinite block. The advantage of this solution is that it does not clutter Special:BlockList. [[mw:Special:MyLanguage/Manual:Block and unblock#Default block duration options|More documentation]] is available. [https://phabricator.wikimedia.org/T398626] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Gadgets can now include <code dir=ltr>.vue</code> files. This makes it easier to develop modern user interfaces using [[mw:Vue.js|Vue.js]], in particular using [[mw:Special:MyLanguage/Codex|Codex]], the official design system of Wikimedia. [[wmdoc:codex/latest/icons/overview.html|Codex icons]] can be loaded through the gadget definition. [[mw:Special:MyLanguage/Extension:Gadgets#Pages|The documentation]] has examples. For user scripts that use Vue.js, an [[mw:API:CodexIcons|API module]] now exists to load Codex icons. [https://phabricator.wikimedia.org/T340460][https://phabricator.wikimedia.org/T311099] * Module developers can now use a [[mw:Help:Extension:Translate/Message Bundles/Lua reference|Lua interface]] to simplify the preparation of Lua modules for translation on Meta-Wiki. This improvement makes it easier for translators to find and edit module strings without dealing with raw Lua code. It helps prevent mistakes that could break the module during translation. Module developers and translators are invited to [[commons:File:Translatable modules video demo July 2025.webm|watch the demo video]], read more about [[mw:Special:MyLanguage/Translatable modules|translatable modules]] to understand how it works, refer to Meta-Wiki's [[m:Module:User Wikimedia project|Module:User Wikimedia project]] for example usage, and [[mw:Talk:Translatable modules|share their feedback]] on how well it addresses the challenges in their workflow. The interface still has some performance issues, so it should not be used in widely used modules yet. [https://phabricator.wikimedia.org/T359918] * Developers of external tools that connect to Wikimedia pages must set a user-agent that complies with [[foundation:Special:MyLanguage/Policy:Wikimedia Foundation User-Agent Policy|the user-agent policy]]. This policy will start to be more strongly enforced in August because of external crawlers that are [[diffblog:2025/04/01/how-crawlers-impact-the-operations-of-the-wikimedia-projects/|overusing]] Wikimedia's resources. Tools that are hosted on Wikimedia's Toolforge or Cloud VPS will not be affected by this for now, but should still set a user-agent. [[phab:T400119|More technical details are available]], and related questions are welcome in that task. * Parsoid Read Views is going to be rolling out to some smaller Wikipedias over the next few weeks, following the successful transition of Wikivoyages and Wiktionaries to Parsoid Read Views. For more information, see the [[mw:Special:MyLanguage/Parsoid/Parser Unification|Parsoid/Parser Unification]] project page. [https://phabricator.wikimedia.org/project/profile/7694/] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.13|MediaWiki]] '''Meetings and events''' * [[wmania:Special:MyLanguage/2025:Wikimania|Wikimania 2025]] will run from August 6–9. The [https://wikimedia.eventyay.com/talk/wikimania2025/schedule/ program is available] for you to plan which sessions you want to attend. Most sessions will be live-streamed, with exceptions for those that show the "no camera" icon. If you are joining online to watch live-streams and use the interactive features, please [[wmania:Special:MyLanguage/2025:Registration|register]] for a free virtual ticket. For example, you may be interested in technical sessions such as: ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/GEH9DH/ Wikimedia’s knowledge infrastructure in a changing internet: Establishing sustainable pathways for content reuse] ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/7ELN9Q/ Wikifunctions is coming soon to a wiki near you!] ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/ZMGVJV/ Shaping the Future of Wikipedia’s Reader Experience] ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/KCKTFZ/ Making Wikipedia More Readable: What Comes Next] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W32"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 03:40, 5 August 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29083927 --> == Tech News: 2025-33 == <section begin="technews-2025-W33"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/33|Translations]] are available. '''Updates for editors''' * The WikiEditor toolbar now includes [[mw:Special:MyLanguage/Help:Extension:WikiEditor#Keyboard shortcuts|its keyboard shortcuts]] in the tooltips for its buttons. This will help to improve the discoverability of this feature. [https://phabricator.wikimedia.org/T400583] * The [[m:Special:MyLanguage/Product and Technology Advisory Council|Product and Technology Advisory Council]] published a set of [[m:Special:MyLanguage/Product and Technology Advisory Council/August 2025 draft PTAC proposals for feedback|proposed experiments]] the Wikimedia Foundation can try to improve communication with community. Feedback on the proposals are welcomed until August 22 on [[m:Talk:Product and Technology Advisory Council/August 2025 draft PTAC proposals for feedback|this talk page]]. * The search bar on the Minerva skin (mobile) has been updated to use the same type-ahead search component that is used on the Vector 2022 skin. There are no changes in search functionality but there are minor visual changes. Specifically, the close-search button has been changed from an "X" to a back arrow. This helps to distinguish it from the other "X" button that is used to clear any text. [https://phabricator.wikimedia.org/T393944] * Editors on some wikis will see a new toggle for "Group results by page" on watchlist, related changes, and recent changes pages. This is [[mw:Special:MyLanguage/Moderator Tools/Watchlist/Experiment|an A/B experiment]] that is planned to start on August 11, and will run for 3–6 weeks on the Bengali, Chinese, Czech, French, Greek, Portuguese, and Urdu Wikipedias. The experiment will examine how making this feature more discoverable might affect editors' ability to find the edits they are looking for. [https://phabricator.wikimedia.org/T396789] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * The multiwiki datasets of [[:wikt:en:Module:Unicode data|Unicode data]] have been moved to [[c:Category:Unicode Module Datasets|Category:Unicode Module Datasets]] on Wikimedia Commons, to follow the idea of "One common data source, multiple local wikis". Most wikis have been updated to use the Commons version. You can ask questions at [[c:Category talk:Unicode Module Datasets|the talkpage]]. [https://en.wiktionary.org/wiki/Module_talk:Unicode_data#Data_from_commons] * Lua code can add warnings when something is wrong, by using the <code dir=ltr>mw.addWarning()</code> function. It is now possible to add more than one warning, instead of new warnings replacing old ones. If you maintain a Lua module that used warnings, you should check it still works as expected. [https://phabricator.wikimedia.org/T398390] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.14|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W33"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:29, 11 August 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29106516 --> == Tech News: 2025-34 == <section begin="technews-2025-W34"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/34|Translations]] are available. '''Updates for editors''' * Later this week, people who are logged-in and have the "[[mw:Special:MyLanguage/Talk pages project/Feature summary|Discussion tools]]" [[Special:Preferences#mw-prefsection-betafeatures|Beta Feature]] enabled will gain the ability to "Thank" individual comments directly from talk pages, rather than needing to navigate to page history. [[mw:Special:MyLanguage/Talk pages project/Feature summary#Comment actions|Learn more about this feature]]. [https://phabricator.wikimedia.org/T400849] * An A/B test comparing two versions of the desktop donate link launched on testwiki on 12 August and on English Wikipedia 14 August for 0.1% of logged out users on the desktop site. The experiment will run for three weeks, ending on 12 September. [https://phabricator.wikimedia.org/T395716] * An A/A test to measure the baseline for reader retention was launched 12 August using [[wikitech:Experimentation Lab|Experimentation Lab]]. This measures the percentage of users who revisit a wiki after their initial visit over a 14-day period. No visual changes are expected. The experiment will run through 31 August. [https://phabricator.wikimedia.org/T399227] * Five new wikis have been created: ** a {{int:project-localized-name-group-wikisource/en}} in [[d:Q34057|Tagalog]] ([[s:tl:|<code>s:tl:</code>]]) [https://phabricator.wikimedia.org/T388639] ** a {{int:project-localized-name-group-wikisource/en}} in [[d:Q36213|Madurese]] ([[s:mad:|<code>s:mad:</code>]]) [https://phabricator.wikimedia.org/T391747] ** a {{int:project-localized-name-group-wikipedia/en}} in [[d:Q3450749|Rakhine]] ([[w:rki:|<code>w:rki:</code>]]) [https://phabricator.wikimedia.org/T392490] ** a {{int:project-localized-name-group-wikibooks/en}} in [[d:Q13324|Minangkabau]] ([[b:min:|<code>b:min:</code>]]) [https://phabricator.wikimedia.org/T395452] ** a {{int:project-localized-name-group-wiktionary/en}} in [[d:Q7598268|Standard Moroccan Amazigh]] ([[wikt:zgh:|<code>wikt:zgh:</code>]]) [https://phabricator.wikimedia.org/T399684] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:46}} community-submitted {{PLURAL:46|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.15|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W34"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:38, 19 August 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29127690 --> == Tech News: 2025-35 == <section begin="technews-2025-W35"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/35|Translations]] are available. '''Updates for editors''' * [[File:Octicons-gift.svg|12px|link=|class=skin-invert|Wishlist item]] [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Template authors can now use additional CSS properties, since the CSS sanitizer used by [[mw:Special:MyLanguage/Help:TemplateStyles|TemplateStyles]] was updated. For example: <code>width: fit-content</code>; <code>ruby-align</code>; relative units such as <code>lh</code>; and custom strings in <code>list-style-type</code>. These improvements are a [[m:Special:MyLanguage/Community Wishlist/Wishes/Allow use of modern CSS in templates by updating the TemplateStyles CSS sanitizer|Community Wishlist wish]]. [https://phabricator.wikimedia.org/T271958][https://phabricator.wikimedia.org/T277755][https://phabricator.wikimedia.org/T293633][https://phabricator.wikimedia.org/T295088][https://phabricator.wikimedia.org/T326906][https://phabricator.wikimedia.org/T340057][https://phabricator.wikimedia.org/T360725][https://phabricator.wikimedia.org/T371809][https://phabricator.wikimedia.org/T375344][https://phabricator.wikimedia.org/T394619] * On large wikis, the default time period to display edits from, within the Special:RecentChanges page, has been changed from 7 days to 1 day. This is part of a performance improvement project. This should have no user-facing impact due to the quantity of edits on these wikis. [https://phabricator.wikimedia.org/T399455] * Administrators can now access the [[{{#special:BlockedExternalDomains}}]] page from the [[{{#special:CommunityConfiguration}}]] list page. This makes it easier to find. [https://phabricator.wikimedia.org/T393240] * Wikimedia Commons videos were not shown in the Videos tab in Google Search. The problem was investigated and reported to Google who have now fixed the issue. [https://phabricator.wikimedia.org/T396168][https://meta.wikimedia.org/wiki/Community_Wishlist/Wishes/Do_something_about_Google_%26_DuckDuckGo_search_not_indexing_media_files_and_categories_on_Commons] * One new wiki has been created: a {{int:project-localized-name-group-wiktionary/en}} in [[d:Q33014|Betawi]] ([[wikt:bew:|<code>wikt:bew:</code>]]) [https://phabricator.wikimedia.org/T402130] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:39}} community-submitted {{PLURAL:39|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Two fields of the [[mw:Special:MyLanguage/Manual:Recentchanges table|recentchanges database table]] are being removed. <code>rc_new</code> and <code>rc_type</code> are being removed in favor of <code>rc_source</code>. Queries to these older fields will start to fail starting this week and developers should use <code>rc_source</code> instead. These older fields were deprecated over 10 years ago and should not be in use. This is part of work to improve the performance and stability of queries to the recentchanges table. [https://phabricator.wikimedia.org/T400696] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.16|MediaWiki]] '''In depth''' * The latest quarterly [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Newsletter/2025/July|Language and Internationalization Newsletter]] is now available. This edition includes: support for new languages in MediaWiki and translatewiki; the start of the Language Onboarding and Development project to help support the growth of new and small wikis; updates on research projects; and more. '''Meetings and events''' * The next [[mw:Special:MyLanguage/Wikimedia Language and Product Localization/Community meetings#29 August 2025|Language Community Meeting]] is happening soon, August 29th at [https://zonestamp.toolforge.org/1756479600 15:00 UTC]. This week's meeting will cover: the Avro keyboard developers from Wikimedia Bangladesh, who were recently awarded a national award for their contributions to this keyboard; and other topics. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W35"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 00:12, 26 August 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29175124 --> == Tech News: 2025-36 == <section begin="technews-2025-W36"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/36|Translations]] are available. '''Weekly highlight''' * The Editing team wants to compile a list of templates, jargon terms, and policies used in edit summaries when a copyright violation is removed. This will help them identify the number of edits reverted due to copyright issues. We invite community members from the following Wikis to list these terms in [[Phab:T402601|T402601]], or to share their list with [[User:Trizek (WMF)|Trizek_(WMF)]]: {{int:project-localized-name-arwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-cswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-dewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-enwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-eswiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-fawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-frwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-hewiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-idwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-itwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-jawiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-kowiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-nlwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-plwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ptwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-trwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-ukwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-viwiki/en}}{{int:comma-separator/en}}{{int:project-localized-name-zhwiki/en}}. This project is open until September 9th 2025. '''Updates for editors''' * The [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents extension]] has been enabled for all Wikisources. The extension makes it easier to organize and participate in collaborative activities, like edit-a-thons and WikiProjects, on the wikis. The extension has three features: [[m:Special:MyLanguage/Event Center/Registration|Event Registration]], [[m:Special:MyLanguage/CampaignEvents/Collaboration list|Collaboration List]], and [[m:Special:MyLanguage/Connection Team/Invitation list|Invitation List]]. To request the extension for your wiki, visit the Deployment information page. [https://meta.wikimedia.org/wiki/CampaignEvents/Deployment_status#How_to_Request_the_CampaignEvents_Extension_for_your_wiki] * The lists in the footer of the editing interface, such as "Templates used on this page," will now be organized into columns when there is enough space. This enhancement minimizes scrolling when editing lengthy articles on Wikipedia. [https://phabricator.wikimedia.org/T401066] * On September 3rd, 2025 we will increase the sampling percentages of our [[mw:Special:MyLanguage/Moderator Tools/Watchlist/Experiment#Scope of the experiment|group by toggle experiment]] of the <code>Special:RecentChanges</code>, <code>Special:Watchlist</code>, and <code>Special:RelatedChanges</code> pages on the Chinese, French, and Portuguese Wikipedias to 100 percent, allowing more editors to be part of this experiment. This adjustment is intended to ensure we have sufficient data to make informed decisions when evaluating the experiment results. [https://phabricator.wikimedia.org/T402958][https://phabricator.wikimedia.org/T396789] * Upon clicking an empty search bar, logged-out users will see suggestions of articles for further reading on English Wikipedia beginning the week of September 22. The feature will be available on both desktop and mobile. All non-English wikis received this change in June and July. The goal is to make it easier for users to find articles. [[mw:Special:MyLanguage/Reading/Web/Content Discovery Experiments/Search Suggestions|Learn more]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:37}} community-submitted {{PLURAL:37|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.17|MediaWiki]] '''In depth''' * Wikifunctions now has a new capability called "lightweight enumeration types", an enumeration type is simply a fixed set of values that's in the type's definition. This capability makes it quick and easy to define such a type, and allows for the reuse of values that are already present in Wikidata. Here is [[f:Special:MyLanguage/Wikifunctions:Status updates/2025-07-19|a newsletter]] to learn more. * The latest [[mw:Special:MyLanguage/Readers/Newsletter updates#August 2025: Newsletter #1|Readers Newsletter]] is now available. This edition includes: the formation of two new teams — Reader Growth and Reader Experience; insights into declining pageviews and account creations; highlights from the Wikimania Nairobi panel on improving the reading experience; upcoming experiments to engage new and existing readers; and more. '''Meetings and events''' * Spotlight on some Wikimania 2025 Sessions: ** Identifying AI-generated text by searching for ISBNs whose checksums fail: Mathias Schindler of WMDE [https://www.youtube.com/watch?v=Dw9o8Lsl974&t=15910s shared tools to help communities search for these]. ** [https://wikimedia.eventyay.com/talk/wikimania2025/talk/TCHZKH/ La durabilité du mouvement Wikimedia face aux défis actuels et futurs]: This session explored how Wikimedia can stay a trusted source of knowledge in the age of generative AI, information overload, and disinformation. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W36"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:50, 1 September 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29196010 --> == Tech News: 2025-37 == <section begin="technews-2025-W37"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/37|Translations]] are available. '''Weekly highlight''' * The Editing team is working on a new check: [[mw:Special:MyLanguage/Paste check|Paste check]]. This check informs newcomers who paste text into Wikipedia that the content might not be accepted. This check is an effort to increase the likelihood that the new content people are adding to Wikipedia is aligned with the Movement's commitment to offering information under a free content license. This check will soon be tested at a few wikis. If your community is interested in this test, please [[phab:T403680|tell us in this task]], or [[mw:Talk:Edit check|contact the team]]. '''Updates for editors''' * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] Later this week, users of the "{{int:codemirror-beta-feature-title}}" [[Special:Preferences#mw-prefsection-betafeatures|beta feature]] will be able to use a [[w:en:Lint (software)|linting tool]] to see errors or other potential problems in wikitext in real time. See the [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Linting|help page for more information]]. [https://phabricator.wikimedia.org/T381577] * [[File:Octicons-tools.svg|12px|link=|class=skin-invert|Advanced item]] When browsing a wiki (like <code dir=ltr>en.wikipedia.org</code>), the software responds in one of two ways: a desktop page, or a redirect to a mobile version on an "m" domain (like <code dir=ltr>en.m.wikipedia.org</code>). Over the next three weeks, MediaWiki will start displaying the mobile version to mobile devices directly on the standard domain, without this redirect. This change does not affect existing m-dot URLs, or the "Desktop view" opt-out. [[mw:Requests for comment/Mobile domain sunsetting/2025 Announcement|Learn more]]. [https://phabricator.wikimedia.org/T214998] * When an edit changes the categories of a page, the changes to the category membership counts are now happening asynchronously. This improves the speed of saving edits, especially when moving many pages to or from the same category, and reduces the risk of site outages, but it means that the counts can show outdated information for a few minutes. [https://phabricator.wikimedia.org/T365303] * Edits on Wikidata to qualifiers (properties and values) and references (properties and values) in a Wikidata item statement will now not add entries to the RecentChanges or Watchlist pages on all other Wikis. This is a temporary change to improve performance while other solutions are created. Wikidata's own pages remain unchanged. [[m:Wikidata For Wikimedia Projects/Reduce change propagation noise#Phase 1: Turn off (temporarily) Qualifiers and References Wikidata edits to the Recent Changes tables|Learn more]]. [https://phabricator.wikimedia.org/T401286][https://phabricator.wikimedia.org/T400698] * Japanese-language wikis have had a major upgrade to the way that search works. The new search should generally give more accurate and more relevant search results. [https://phabricator.wikimedia.org/T318269] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.18|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W37"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 01:14, 9 September 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29238161 --> == Tech News: 2025-38 == <section begin="technews-2025-W38"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/38|Translations]] are available. '''Updates for editors''' * References lists that are made using the <code dir=ltr><nowiki><references/></nowiki></code> [[mw:Special:MyLanguage/Help:Cite#references-tag|tag]] will now automatically display with columns in Vector 2022 when readers are using its 'standard' settings for text-size and page-width. [https://phabricator.wikimedia.org/T334941] * Starting in the week of October 6, on [[gitiles:operations/mediawiki-config/+/a2d2aaab9ace84280dd2f4c70a33bb69cd73850f/dblists/small.dblist|small wikis]] and [[gitiles:operations/mediawiki-config/+/a2d2aaab9ace84280dd2f4c70a33bb69cd73850f/dblists/medium.dblist|medium wikis]] that have the [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents extension]] enabled, all autoconfirmed users will be able to use [[m:Special:MyLanguage/Event Center/Registration|Event Registration]] as an organizer. No changes will be made for [[gitiles:operations/mediawiki-config/+/a2d2aaab9ace84280dd2f4c70a33bb69cd73850f/dblists/large.dblist|large wikis]] unless requested in Phabricator. This change is being made to make it easier for more people to use Event Registration, especially on wikis that are less likely to have policies related to the Event Organizer right. [[m:Special:MyLanguage/CampaignEvents/Proposal to grant autoconfirmed users on small and medium wikis the organizer access to the event registration tool|Learn more]]. * Users that search using regular expressions (regex) can now use additional features including: ** for the <code dir=ltr>intitle:</code> keyword: [[mw:Special:MyLanguage/Help:CirrusSearch#Metacharacters|metacharacters]] for start-of-line (<code dir=ltr>^</code>) and end-of-line (<code dir=ltr>$</code>) anchors [https://phabricator.wikimedia.org/T317599] ** for both <code dir=ltr>intitle:</code> and <code dir=ltr>insource:</code> keywords: shorthand [[mw:Special:MyLanguage/Help:CirrusSearch#Character_Classes|character classes]] for digits (<code dir=ltr>\d</code>), whitespace (<code dir=ltr>\s</code>), and word characters (<code dir=ltr>\w</code>); and [[mw:Special:MyLanguage/Help:CirrusSearch#Escape codes|escape codes]] for line feed (<code dir=ltr>\r</code>), newline (<code dir=ltr>\n</code>), tab (<code dir=ltr>\t</code>), and unicode (e.g. <code dir=ltr>\uHHHH</code>). [https://phabricator.wikimedia.org/T403212] * When you search for text that looks like an IP, the system will now show search results. It used to take you to the contributions for that IP instead of showing search results. [https://phabricator.wikimedia.org/T306325] * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on September 24. This is planned at [https://zonestamp.toolforge.org/1758726000 15:00 UTC]. This is for the datacenter server switchover backup tests which happen twice a year. You can [[diffblog:2025/03/12/hear-that-the-wikis-go-silent-twice-a-year/|read more about the background and details of this process on the Diff blog]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:24}} community-submitted {{PLURAL:24|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug was fixed that affected users who used the page-tabs to switch from wikitext editing of a section into the visualeditor. [https://phabricator.wikimedia.org/T401043] '''Updates for technical contributors''' * The MediaWiki Interfaces team is redesigning the Wikimedia REST API Sandbox with Codex. If you have feedback on improvements for the API documentation or what makes developer experiences smooth (or frustrating), you’re invited to [https://calendar.google.com/calendar/u/0/appointments/schedules/AcZssZ2aZzbXeQvjOF7gB1fJXiwAYemQjKf4sXNaRODPA7_obFyNBwkzNkoVCoTF-aeov89kIjXHbCQm join an upcoming discovery interview], or [[mw:MediaWiki Interfaces Team/Developer Feedback/Wikimedia Web APIs|leave feedback onwiki]]. [[listarchive:list/wikitech-l@lists.wikimedia.org/thread/C4FBAOA57PH6G5ORVMAUF5TGYBLZDU5Q/|Learn more]]. * Edits to Wikidata aliases (an alternative name for an item or a property) will now be shown in RecentChanges and Watchlist entries on other wikis less often, reducing unnecessary notifications. This will reduce the overall quantity of 'noisy' entries. Wikidata's own pages remain unchanged. [[m:Wikidata For Wikimedia Projects/Reduce change propagation noise#Phase 1: More granular Alias tracking|Learn more]]. [https://phabricator.wikimedia.org/T401288] * The new [https://www.unicode.org/versions/Unicode17.0.0/ Unicode 17.0] version has been released. The [[:c:Category:Unicode Module Datasets|datasets on Commons]] for the [[:d:Q39301585|Module:Unicode data]] have been updated. Wikipedias that do not use the Commons datasets should either update their own data or switch to the Commons datasets. * Users of the [[m:Special:MyLanguage/Wikimedia Enterprise|Wikimedia Enterprise]] Structured Contents endpoints can now access [https://enterprise.wikimedia.com/blog/parsed-wikipedia-tables/ Parsed Tables]. The new Parsed Tables feature extracts and represents Wikipedia tables in structured JSON. This improves machine accessibility as part of the [https://enterprise.wikimedia.com/api/structured-contents/ Structured Contents initiative]. Structured Contents output is freely available through the [https://enterprise.wikimedia.com/docs/on-demand/#article-structured-contents-beta On-demand API], or through Wikimedia Cloud Services. * A [https://www.kaggle.com/datasets/wikimedia-foundation/english-wikipedia-people-dataset dataset of English Wikipedia biographical information] from [[m:Special:MyLanguage/Wikimedia Enterprise|Wikimedia Enterprise]] has been published on Kaggle, for evaluation and research. This provides structured data from more than 1.5 million biographies, including birth and death dates, education, affiliations, careers, awards, and more (from a June 2024 snapshot). * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.19|MediaWiki]] '''Meetings and events''' * [[wmania:Special:MyLanguage/2026:Scholarships|Scholarship applications]] for Wikimania 2026 in Paris, France, are open until October 31. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W38"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:07, 15 September 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29263921 --> == Tech News: 2025-39 == <section begin="technews-2025-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/39|Translations]] are available. '''Weekly highlight''' * [https://zonestamp.toolforge.org/1758726000 On September 24th at 15:00 UTC], all Wikimedia sites users will experience a brief read-only period due to a scheduled [[m:Special:MyLanguage/Tech/Server switch|datacenter server switchover]]. The Wikimedia Foundation's Site Reliability Engineering (SRE) team will redirect all traffic from one primary server to its backup. You can listen to the switchover using the [http://listen.hatnote.com/ "Listen to Wikipedia"] tool, where you will hear edits stop for a few minutes during the read-only phase, then resume. This twice-yearly datacenter server switchover ensures reliability by testing the backup datacenter, so that our sites can stay online even if the primary datacenter fails. You can [[diffblog:2025/03/12/hear-that-the-wikis-go-silent-twice-a-year/|read more about the process on the Diff blog]]. '''Updates for editors''' * Editors of [[f:Special:Mylanguage/Wikifunctions:Status updates/2025-09-12#Next round of Wiktionaries to receive embedded Wikifunctions calls|60 more Wiktionaries]] will soon be able to call [[f:Special:MyLanguage/Wikifunctions:Introduction|functions from Wikifunctions]] and integrate them into their pages. A function takes one or more inputs and transforms them into a desired output, like adding numbers, converting miles to meters, calculating elapsed time, or declining a word into a case. They will join the other [[f:Special:MyLanguage/Wikifunctions:Status updates/2025-08-29#Wikifunctions available on 65 Wiktionaries|65 Wiktionary language editions]], which already have access to embedded Wikifunctions calls. Later this year, plans are in place to expand to more Wiktionaries and the Incubator. * A new [[mw:Special:MyLanguage/Help:Magic words#Technical metadata of another page|parser function]] has been added: <code><nowiki>{{#contentmodel}}</nowiki></code>. Template editors and admins can use it to get the localized or canonical name of the [[mw:Special:MyLanguage/Help:ChangeContentModel|content model]] of a specific page. The function makes it easier to create and edit system messages, such as ''MediaWiki:editinginterface'', even when you switch types of pages, like wiki, JavaScript, CSS or JSON page. [https://phabricator.wikimedia.org/T328254] * Adding or editing a <code>DISPLAYTITLE</code> for an article using VisualEditor will no longer be broken. Editors who use VisualEditor mode to modify the <code><nowiki>{{DISPLAYTITLE}}</nowiki></code> would no longer have the literal text "DISPLAYTITLE" or its localized variant added to their articles. A list of pages that may have been affected and might need cleanup is documented in [[phab:P83438|this ticket]]. * Beta users of the Wikipedia Android app can now try the redesigned [[mw:Special:MyLanguage/Wikimedia Apps/Team/Android/Activity Tab Experiment|Activity tab]], which replaces the Edits tab. The new tab offers personalized insights into reading, editing, and donation activity, while simplifying navigation and making app use more engaging. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:12}} community-submitted {{PLURAL:12|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.20|MediaWiki]] '''In depth''' * Wikifunctions users can now import many essential facts involving [[f:Special:MyLanguage/Z6011|geo-coordinates]], [[f:Special:MyLanguage/Z6010|quantities]] and [[f:Special:MyLanguage/Z6064|time]] values from Wikidata. This is made possible by the creation of Wikifunctions types for these values, which makes them available for use by functions in Wikifunctions. Learn more about how this works in [[c:File:ImportingWikidataDatatypesIntoWikifunctions.webm|this video]] and Wikifunctions' [[f:Special:MyLanguage/Wikifunctions:Status updates/2025-08-01#News in Types I: Wikidata quantity|August 1 newsletter]] (for quantities) and [[f:Special:MyLanguage/Wikifunctions:Status updates/2025-08-22#News in Types: Wikidata geo-coordinate|August 22 newsletter]] (for geo-coordinates). '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W39"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 22:55, 22 September 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29305556 --> == Tech News: 2025-40 == <section begin="technews-2025-W40"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/40|Translations]] are available. '''Weekly highlight''' * A major software upgrade has been made to [[phab:|Phabricator]]. The update introduces performance improvements, a refreshed search interface, enhancements to Maniphest task search, updates to user profile pages and project workboards, new Herald automation features, as well as general text input, mobile experience improvements and more. [https://phabricator.wikimedia.org/phame/post/view/321/iterative_improvements_september_2025/] '''Updates for editors''' * The Community Tech team will release the new Community Wishlist extension on October 1, that will improve the way wishes will be submitted. The new extension will allow users to add tags to their wishes to better categorise them, and (in a future iteration) to filter them by status, tags and focus areas. It will also be possible to support individual wishes again, as requested by the community in many instances. The old system will be retired. There will be a brief period of downtime while the extension is deployed and wishes are migrated to the new system. You can read more about this [[:m:Special:MyLanguage/Community Wishlist/Updates|in the latest update]] or you can consult the [[:mw:Special:MyLanguage/Help:Extension:CommunityRequests|current documentation on MediaWiki]]. * As announced [[diffblog:2025/09/02/better-detecting-bots-and-replacing-our-captcha/|on Diff blog]], the production trial of the [[mw:Special:MyLanguage/Product Safety and Integrity/Anti-abuse signals/hCaptcha|hCaptcha]] service for bot detection has begun. The trial is currently using hCaptcha to protect account creation on Chinese, Persian, Portuguese, Indonesian, Japanese, and Turkish Wikipedias, where it will replace our existing [[mw:Special:MyLanguage/Extension:ConfirmEdit#FancyCaptcha|CAPTCHA]] (FancyCaptcha). The goal with the trial is to better block bots while also improving usability and accessibility for users who encounter CAPTCHA challenges. * The [[mw:Special:MyLanguage/Extension:CampaignEvents|CampaignEvents]] extension has been [[m:Special:MyLanguage/CampaignEvents/Deployment status|deployed]] to Wikimedia Commons. The extension makes it easier to organize and participate in collaborative activities, like edit-a-thons and WikiProjects, on the wikis. On Commons, anyone who is a registered user can use it as an event participant. To use it as an organizer, someone needs to have the [[c:Special:MyLanguage/Commons:Event organizers|event organizer right]]. * [[:m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|Sub-referencing]], a new feature to re-use references with different details has been released to German Wikipedia. You can [[:m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#test|test the feature]] on testwiki or [https://en.wikipedia.beta.wmcloud.org/wiki/Sub-referencing on betawiki] as well. Please share your thoughts on [[:m:Talk:WMDE Technical Wishes/Sub-referencing#Templates used in sub-references|using templates in sub-references]] or [[:m:Talk:WMDE Technical Wishes/Sub-referencing#Pilot wikis|volunteer to become a pilot wiki]]. * On wikis using the [[mw:Special:MyLanguage/Help:Growth/Mentorship|Mentorship]] system, communities can now opt experienced editors out of Mentorship through [[{{#special:CommunityConfiguration/Mentorship}}]]. Within this setting, communities may define thresholds, based on edit count and account age, to decide when an editor is considered experienced enough to no longer receive Mentorship. [https://phabricator.wikimedia.org/T403563] * The Editing Team and the Machine Learning Team are working on a new check for newcomers: [[mw:Special:MyLanguage/Edit check/Tone Check|Tone check]]. Using a prediction model, this check will encourage editors to improve the tone of their edits, using artificial intelligence. We invite volunteers to review the first version of the Tone language model for the following languages: Arabic, Czech, German, Hebrew, Indonesian, Dutch, Polish, Russian, Turkish, Chinese, Farsi, Italian, Norwegian, Romanian and Latvian. Users from these wikis interested in reviewing this model are [[mw:Special:MyLanguage/Edit_check/Tone_Check/Model_evaluation|invited to sign up at MediaWiki.org]]. The deadline to sign up is on October 3, which will be the start date of the test. * The rollout of [[:mw:Special:MyLanguage/Help:Manage blocks|multiblocks]] had the side effect that non-active block logs may have been shown on {{#special:Contributions}} and on blocked users' user and user_talk pages. This issue will be fully resolved in a few days. As part of the fix, [{{fullurl:Special:Allmessages|prefix=sp-contributions-blocked-notice}} messages prefixed with <code>sp-contributions-blocked-notice</code>] will be removed and replaced with [{{fullurl:Special:Allmessages|prefix=blocked-notice-logextract}} those prefixed with <code>blocked-notice-logextract</code>] in a few weeks. Please help translate the new messages and update any local overrides if needed. * There was a bug with links added using visual editor if they included characters such as <code dir=ltr><nowiki>[ ] |</nowiki></code> after the fragment identifier (<code><nowiki>#</nowiki></code>). They were not encoded properly creating an incorrect link. This has been fixed. [https://phabricator.wikimedia.org/T404823] * One new wiki has been created: a {{int:project-localized-name-group-wikiquote/en}} in [[d:Q9237|Malay]] ([[q:ms:|<code>q:ms:</code>]]) [https://phabricator.wikimedia.org/T404698] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:21}} community-submitted {{PLURAL:21|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the [[mw:Special:MyLanguage/Product Safety and Integrity/Anti-abuse signals/User Info|User Info Card]] now displays currently active global lock/blocks. [https://phabricator.wikimedia.org/T401128] '''Updates for technical contributors''' * Later this week, editors using Lua modules will be able to use the <code>[[mw:Special:MyLanguage/Extension:Scribunto/Lua reference manual#mw.title.newBatch|mw.title.newBatch]]</code> function to look up the existence of up to 25 pages at once, in a way that only increases the [[mw:Special:MyLanguage/Manual:Parser functions#Expensive parser functions|expensive function]] count once. * A new [[m:Special:MyLanguage/Product and Technology Advisory Council/Unsupported Tools Working Group|Unsupported Tools Working Group]] has been formed as part of ongoing efforts to collectively determine technical work priorities, similar to the [[m:Special:MyLanguage/Product and Technology Advisory Council|Product & Technology Advisory Council]] (PTAC). The working group will help prioritize and review requests for support of unmaintained extensions, gadgets, bots, and tools. For the first cycle, the group will be prioritizing an unsupported Wikimedia Commons tool. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.21|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W40"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:52, 29 September 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29355230 --> == Tech News: 2025-41 == <section begin="technews-2025-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/41|Translations]] are available. '''Weekly highlight''' * [[mw:Special:MyLanguage/Help:Edit check#paste|Paste Check]] is a new Edit Check feature to help avoid and fight copyright violations. When editors paste text into an article, Paste Check prompts them to confirm the origin and licensing of the content. Starting Wednesday, 8 October, [[phab:T403680|22 wikis will test Paste Check]]. Paste Check will help new volunteers understand and follow the policies and guidelines necessary to make constructive contributions to Wikipedia projects. '''Updates for editors''' * Mobile devices will receive mobile articles directly on the standard domain (like <code>en.wikipedia.org</code>), instead of via a redirect to an "m" domain (like <code>en.m.wikipedia.org</code>). This change improves performance. This week it will be enabled on Wikipedias. The existing mobile URLs and the "Desktop view" opt-out remain available. [[mw:Requests for comment/Mobile domain sunsetting/2025 Announcement|Learn more]]. [https://phabricator.wikimedia.org/T214998] * New [[mw:Special:MyLanguage/Help:CirrusSearch#creationdate and lasteditdate|date filters]], <code dir=ltr>creationdate:</code> and <code dir=ltr>lasteditdate:</code>, are now available in the wiki search engine. This allows users to filter search results by a page's first or last revision date. The filters support comparison operators (e.g. <code dir=ltr>>2024</code>) and relative dates (e.g. <code dir=ltr>today-1d</code>), making it easier to find recently updated content or pages within specific age ranges. [https://phabricator.wikimedia.org/T403593] * [[f:|Wikifunctions]] now supports rich text in embedded calls across the 150 wikis where it's enabled. To showcase this, the team created a [[f:Z26333|Latin declination table]] that Wiktionary editors can use to automatically generate noun forms, producing clear, formatted results — see an [[f:Wikifunctions:Embedded function calls/Wiktionary tables demonstration|example output]]. If you need any help or have any feedback, please [[f:Wikifunctions:Project chat|contact the Wikifunctions Team]]. [https://phabricator.wikimedia.org/T397402] * An edit link will now appear inside the categories box on article pages for logged in users, which will directly launch the VisualEditor category dialog. [https://phabricator.wikimedia.org/T291691] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:34}} community-submitted {{PLURAL:34|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, there was a problem downloading pdf files last week and that has been resolved. [https://phabricator.wikimedia.org/T405957] '''Updates for technical contributors''' * The field <code dir=ltr>rev_sha1</code> in the revision database table is being removed in favor of <code dir=ltr>content_sha1</code> in the content database table. See [https://lists.wikimedia.org/hyperkitty/list/cloud@lists.wikimedia.org/thread/2D2M3SP4WHR6BXXKTZ2PBLZQYR3EGQVR/ the announcement] for more information. * The [[mw:Special:MyLanguage/Reading/Web|Reader Experience team]] will roll out [[w:en:Light-on-dark color scheme|Dark Mode]] user interface on all Wikimedia sites on October 29, 2025. All anonymous users of Wikimedia sites will have the option to activate a color scheme that features light-colored text on a dark background. This is designed to provide a more comfortable reading experience, especially in low-light situations. Template authors and technical contributors are encouraged to [[mw:Special:MyLanguage/Reading/Web/Accessibility for reading/Updates/2024-04|learn how to make pages ready for Dark mode]] and address any compatibility issues found in templates in their wiki before the enablement. Please contact the Web team for questions or any support on [[mw:Talk:Reading/Web/Accessibility for reading#|this talk page]] before the enablement. [https://phabricator.wikimedia.org/T395628] * Starting on Monday, October 6, API endpoints under the <code>rest.php</code> path will be rerouted through a new internal API Gateway. Individual wikis will be updated based on the standard release groups, with total traffic increased over time. This change is expected to be non-breaking and non-disruptive. If any issues are observed, please file a Phabricator ticket to the [[phab:tag/serviceops/|Service Ops team board]]. [https://phabricator.wikimedia.org/T400130] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.22|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W41"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:23, 6 October 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29400897 --> == Tech News: 2025-42 == <section begin="technews-2025-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/42|Translations]] are available. '''Weekly highlight''' * Last week, improvements to account security and two-factor authentication (2FA) features were enabled across all wikis. These changes include user interface improvements for [https://auth.wikimedia.org/metawiki/wiki/Special:AccountSecurity Special:AccountSecurity], the support of multiple 2FA methods via authenticator apps and portable security keys (previously users could only enable one method), and a new Recovery Codes module which facilitates fewer account lockouts due to lost two-factor apps and devices. As part of the [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security|Account Security]] project, work is continuing through the rest of 2025 on further user experience improvements, and support for passkeys as an alternate second factor. '''Updates for editors''' * Another part of the Account security project is making 2FA generally available to all users. Along with editors with advanced privileges, such as administrators and bureaucrats, 40% of editors now have access to 2FA. You can check if you have access at [https://auth.wikimedia.org/metawiki/wiki/Special:AccountSecurity Special:AccountSecurity]. Instructions for activation are on the linked page. The plan is to continue increasing availability if it is determined that the user support capabilities are able to support global usage. [https://phabricator.wikimedia.org/T400579] * This week, users at wikis where talk page [[mw:Special:MyLanguage/Talk pages project/Usability|Usability Improvements]] are already available by default (everywhere ''except'' the 12 wikis listed in [[phab:T379264|T379264]]) will gain the ability to Thank a comment directly from the talk page it appears on. Before this change, Thanking could only be done by visiting the revision history of the talk page. You can [[diffblog:2025/10/13/revolutionizing-gratitude-a-new-era-of-thanking-comments/|learn more about this change]]. [https://phabricator.wikimedia.org/T366095] * Users who have not [[Special:Preferences#mw-prefsection-personal-email|verified their email address]] will soon be receiving monthly Notification reminders to do so. This is because users who have verified their email can more easily recover their account. These reminders will not be sent if the user is inactive or removes the unverified email from their account. [https://www.mediawiki.org/wiki/Special:MyLanguage/Help:Email_confirmation][https://phabricator.wikimedia.org/T58074] * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:21}} community-submitted {{PLURAL:21|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a fix was made for an occasional error with saving translated paragraphs in the Content Translation tool, and the related error messages are now easier to see. [https://phabricator.wikimedia.org/T376531] '''Updates for technical contributors''' * The Unsupported Tools Working Group has chosen [[c:Special:MyLanguage/Commons:Video2commons|Video2Commons]] as the first tool for its pilot cycle. The group will explore ways to improve and sustain the tool over the coming months. [[m:Special:MyLanguage/Product and Technology Advisory Council/Unsupported Tools Working Group|Learn more on Meta]]. * [[File:Octicons-sync.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.23|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W42"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:59, 13 October 2025 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29434481 --> == Tech News: 2025-43 == <section begin="technews-2025-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/43|Translations]] are available. '''Updates for editors''' * To optimize how user data is stored in our databases, the saved preferences of users who haven't logged in for over five years and have fewer than 100 edits will be cleared. When those users return, default settings will apply. [https://phabricator.wikimedia.org/T406724] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, there was a broken link from the GlobalContributions interface message to the XTools GlobalContributions page which has now been fixed. [https://phabricator.wikimedia.org/T406415] '''Updates for technical contributors''' * The work to reroute all traffic to API endpoints under the <code dir=ltr><nowiki>rest.php</nowiki></code> route through a common API gateway is now complete. If any issues are observed, please file a phabricator ticket to the [[phab:tag/serviceops/|Service Ops team board]]. * Edits to Wikidata references or qualifiers will now be shown in RecentChanges and Watchlist entries on other wikis less often, reducing unnecessary notifications. This will reduce the overall quantity of 'noisy' entries. Wikidata's own pages remain unchanged. [https://phabricator.wikimedia.org/T401290] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.24|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W43"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:36, 20 October 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29478670 --> == Tech News: 2025-44 == <section begin="technews-2025-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/44|Translations]] are available. '''Updates for editors''' * The Wikipedia iOS app has launched an A/B/C test of improvements made to the tabbed browsing feature for select regions and languages. The test, named “More dynamic tabs”, explores new tab experiences and includes “Did you know” and “Because you read” article recommendations. You can [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/Tabbed Browsing (Tabs)/New Tab Experience and Recommendations Experiment|read more on the project page]]. * Autoconfirmed users on [[gitiles:operations/mediawiki-config/+/a2d2aaab9ace84280dd2f4c70a33bb69cd73850f/dblists/small.dblist|small]] and [[gitiles:operations/mediawiki-config/+/a2d2aaab9ace84280dd2f4c70a33bb69cd73850f/dblists/medium.dblist|medium wikis]] with the CampaignEvents extension can now use [[m:Special:MyLanguage/Event Center/Registration|Event Registration]] without the Event Organizer right. This feature lets organizers enable registration, manage participants, and lets users register with one click instead of signing event pages. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue of flashing colors when holding or pressing the arrow keys under the dark mode settings in Vector 2022 has been fixed. [https://phabricator.wikimedia.org/T402285] '''Updates for technical contributors''' * The CampaignEvents extension will be deployed to all remaining wikis during the week of 17 November 2025. The extension currently includes three features: Event Registration, Collaboration List, and Invitation List. For this rollout, Invitation List will not be enabled on Wikifunctions and MediaWiki unless requested by those communities. [[m:Special:MyLanguage/CampaignEvents/Deployment status|Visit the deployment page to learn more]]. * The SwaggerUI-based REST sandbox experience is now live on all wiki projects. The sandbox can be accessed through the [[{{#special:RestSandbox}}]] page. Please report any issues to the MediaWiki Interfaces team board, or join the discussion on the [[mw:Special:MyLanguage/MediaWiki Interfaces Team/Feature Feedback/REST Sandbox|project launch]] page. [https://phabricator.wikimedia.org/project/board/6931/] * Transform endpoints with a trailing slash path in the MediaWiki REST API are now marked as deprecated. They will remain functional during this time, but removal is expected by the end of January 2026. All API users currently calling them are encouraged to transition to the non-trailing slash versions. Both endpoint variations can be found and tested using the [https://test.wikipedia.org/w/index.php?api=mw-extra&title=Special%3ARestSandbox REST Sandbox]. See the [[mw:API/Deprecation|MediaWiki REST API Deprecation]] page for more detailed information about the API deprecation policies and procedures. * A dedicated [[mw:API:REST API/Changelog|changelog now exists for the MediaWiki REST API]]. The changelog provides an overview of these changes, making it easier for developers to keep track of improvements and iterations. Announcements will also continue to flow through the standard communication channels, including Tech News and email distribution lists, but can now be more easily referenced from a central location. If you have feedback about the style, structure, or content of this changelog, please [[mw:API talk:REST API/Changelog|join the discussion]]. * Administrators can delete the tracking category which was previously added by the JsonConfig extension, as it is no longer used. See the categories linked from [[d:Q130635582#sitelinks-wikipedia|Q130635582]]. It is OK if there are still pages listed in the category as that is just a caching issue, and they will be automatically cleared out the next time each page is edited. [https://phabricator.wikimedia.org/T378352] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.25|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W44"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:31, 27 October 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29513638 --> == Tech News: 2025-45 == <section begin="technews-2025-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/45|Translations]] are available. '''Updates for editors''' * Administrators will now find that [[{{#special:MergeHistory}}]] is now significantly more flexible about what it can merge. It can now merge sections taken from the middle of the history of the source (rather than only the start) and insert revisions anywhere in the history of the destination page (rather than only the start). [https://phabricator.wikimedia.org/T382958] * For users with "{{int:discussiontools-preference-autotopicsub}}" [[Special:Preferences#mw-prefsection-editing|enabled in their preferences]], starting a new topic or adding a reply to an existing topic will now subscribe them to replies to that topic. Previously, this would only happen if the DiscussionTools "{{int:Skin-action-addsection}}" or "{{int:Discussiontools-replybutton}}" widgets were used. When DiscussionTools was originally launched existing accounts were not opted in to automatic topic subscriptions, so this change should primarily affect newer accounts and users who have deliberately changed their preferences since that time. [https://phabricator.wikimedia.org/T290778] * Scribunto modules can now be used to [[mw:Special:MyLanguage/Extension:Scribunto/Lua reference manual#SVG library|generate SVG images]]. This can be used to build charts, graphics and other visualizations dynamically through Lua, reducing the need to compose them externally and upload them as files. [https://phabricator.wikimedia.org/T405861] * Wikimedia sites now provide all anonymous users with the option to enable a dark mode color scheme, featuring light-colored text on a dark background. This enhancement aims to deliver a more enjoyable reading experience, especially in dimly lit environments. [https://phabricator.wikimedia.org/T395628] * Users with large watchlists have long faced timeouts when editing [[Special:EditWatchlist|Special:EditWatchlist]]. The page now loads entries in smaller sections instead of all at once due to a paging update, allowing everyone to edit their watchlists smoothly. As part of the database update, sorting by expiry has been removed because it was over 100× slower than sorting by title. A [https://meta.wikimedia.org/wiki/Community_Wishlist/W454 community wish] has been created to explore alternative ways to restore sort-by-expiry. If this feature is important to you, please support the wish! [https://phabricator.wikimedia.org/T41510] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:31}} community-submitted {{PLURAL:31|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the fixing of the persisting highlighting when using VisualEditor find and replace during a query. [https://phabricator.wikimedia.org/T407318] '''Updates for technical contributors''' * Since 2019 the [[m:Special:MyLanguage/Wikimedia URL Shortener|Wikimedia URL Shortener]] at https://w.wiki is available for all Wikimedia wikis to create short links to articles, permalinks, diffs, etc. It is available in the sidebar as "Get shortened URL". There are 30 wikis that also install an older "ShortUrl" extension. The old extension will soon be removed. This means <code>/s/</code> URLs will not be advertised under article titles via HTML <code dir=ltr>class="title-shortlink"</code>. The <code>/s/</code> URLs will keep working. [https://phabricator.wikimedia.org/T107188] * On Thursday, October 30, the [[:mw:Special:MyLanguage/MediaWiki Interfaces Team|MediaWiki Interfaces]] and [[:mw:Special:MyLanguage/Wikimedia Site Reliability Engineering|SRE Service Operations]] teams began rerouting Action API traffic through a common API gateway. Individual wikis will be updated based on the standard release groups, with total traffic increased over time. This change is expected to be non-breaking and non-disruptive. If any issues are observed, please file a Phabricator ticket to the [https://phabricator.wikimedia.org/tag/serviceops/ Service Ops team] board. * MediaWiki Train deployments will pause for the final two weeks of 2025: 22 December and 29 December. Backport windows will also pause between Monday, 22 December 2025 and Thursday, 2 January 2026. A backport window is a scheduled time to add things like bug fixes and configuration changes. There are seven deployment trains remaining for 2025. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/SMWTEAES4SDLDUSK4HMWNBSKNCXZAWYN/] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.45/wmf.26|MediaWiki]] '''In depth''' * In 2025, the Wikimedia Foundation reported that AI systems and search engines increasingly use Wikipedia content without driving users to the site, contributing to an 8% drop in human pageviews compared to 2024. After detecting bots disguised as humans, Wikimedia updated its traffic data to reflect this shift. Read more about current user trends on Wikipedia in [[diffblog:2025/10/17/new-user-trends-on-wikipedia/|a Diff blog post]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W45"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:34, 3 November 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29552512 --> == Tech News: 2025-46 == <section begin="technews-2025-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/46|Translations]] are available. '''Updates for editors''' [[File:Talk pages default look (April 2023).jpg|thumb|alt=Screenshot of the visual improvements made on talk pages|Example of a talk page with the new design, in French.]] * Starting November 12, users will see a change in the [[m:Special:MyLanguage/Talk pages project/Feature summary#Usability improvements|appearance of talk pages]] on [[Phab:T379264|some Wikipedias]]. Almost [[phab:T392121|all wikis]] have received this design change; [[phab:T409297|English Wikipedia]] will get these changes later. You can read more [[diffblog:2024/05/02/making-talk-pages-better-for-everyone/|on ''Diff'']]. Users can opt out of these changes [[Special:Preferences#mw-prefsection-editing|in their user preferences]] in "{{int:discussiontools-preference-visualenhancements}}". [https://phabricator.wikimedia.org/T379264] * MediaWiki can now display a [[mw:Special:MyLanguage/Help:Protection indicators|page indicator]] automatically while a page is protected. This feature is disabled by default. It can be enabled by [[m:Special:MyLanguage/Requesting wiki configuration changes|community request]]. [https://phabricator.wikimedia.org/T12347] * Using the "{{int:showpreview}}" or "{{int:showdiff}}" buttons in the wikitext editor will now carry over certain URL parameters like '[[mw:Special:MyLanguage/Manual:Parameters to index.php#useskin|useskin]]', '[[mw:Special:MyLanguage/Manual:Parameters to index.php#uselang|uselang]]' and '[[mw:Special:MyLanguage/Help:Section#Editing sections|section]]'. This update also fixes an issue where, if the browser crashed while previewing an edit to a single section, saving this edit could overwrite the entire page with just that section’s content. [https://phabricator.wikimedia.org/T62744][https://phabricator.wikimedia.org/T24029][https://phabricator.wikimedia.org/T155097] * Wikivoyage wikis can use [[mw:Special:MyLanguage/Help:Extension:Kartographer#Markers and counters|colored map markers in the article text]]. The text of these markers will now be shown in contrasting black or white color, instead of always being white. Local workarounds for the problem can be removed. [https://phabricator.wikimedia.org/T369454] * The Activity tab in the Wikipedia Android app is now available for all users. The new tab offers personalized insights into reading, editing, and donation activity, while simplifying navigation and making app use more engaging. [https://www.mediawiki.org/wiki/Wikimedia_Apps/Team/Android/Activity_Tab_Experiment] * The Reader Growth team is launching an experiment called "Image browsing" to test how to make it easier for readers to browse and discover images on Wikipedia articles. This experiment, a mobile-only A/B test, will go live on English Wikipedia in the week of November 17 and will run for four weeks, affecting 0.05% of users on English wiki. The test launched on November 3 on Arabic, Chinese, French, Indonesian, and Vietnamese wikis, affecting up to 10% of users on those wikis. [https://www.mediawiki.org/wiki/Readers/Reader_Growth/WE3.1.3_Image_Browsing] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example the inability to lock accounts on mobile sites has been fixed. [https://phabricator.wikimedia.org/T256185] '''Updates for technical contributors''' * [[wikitech:Help talk:Toolforge/Toolforge standards committee#November 2025 committee nominations|Nominations are open on Wikitech]] for new [[wikitech:Help:Toolforge/Toolforge standards committee|Toolforge standards committee]] members. The committee oversees the Toolforge [[wikitech:Help:Toolforge/Right to fork policy|Right to fork policy]] and [[wikitech:Help:Toolforge/Abandoned tool policy|Abandoned tool policy]] among other duties. Nominations will remain open through 2025-11-28. * The [[w:JSON Web Token#Standard fields|JWT issuer field]] in [[mw:Special:MyLanguage/OAuth/For Developers#OAuth 2|OAuth 2 access tokens]] for [[m:Special:MyLanguage/Help:Unified login|SUL wikis]] has been changed to <code><nowiki>https://meta.wikimedia.org</nowiki></code>. Old access tokens will still work. [https://phabricator.wikimedia.org/T399199] * The [[w:JSON Web Token#Standard fields|JWT subject field]] in [[mw:Special:MyLanguage/OAuth/For Developers#OAuth 2|OAuth 2 access tokens]] will soon change from <code><user id></code> to <code dir=ltr style="white-space:nowrap">mw:<identity type>:<user id></code>, where <code><identity type></code> is typically <code dir=ltr>CentralAuth:</code><!-- not a typo --> (for [[m:Special:MyLanguage/Help:Unified login|SUL wikis]]) or <code dir=ltr style="white-space:nowrap">local:<wiki id></code> (for other wikis). This is to avoid conflicts between different user ID types, and to make OAuth 2 access tokens and the <code>sessionJwt</code> cookie more similar. Old access tokens will still work. [https://phabricator.wikimedia.org/T399199] * MediaWiki's block messages ([[MediaWiki:Blockedtext|blockedtext]], [[MediaWiki:Blockedtext-partial|blockedtext-partial]], [[MediaWiki:Autoblockedtext|autoblockedtext]], [[MediaWiki:Systemblockedtext|systemblockedtext]], [[MediaWiki:Blockedtext-tempuser|blockedtext-tempuser]], [[MediaWiki:Autoblockedtext-tempuser|autoblockedtext-tempuser]]) now support additional parameters indicating whether the user is blocked from editing their own user talk page <code><nowiki>$9</nowiki></code> or emailing other users <code><nowiki>$</nowiki><nowiki>10</nowiki></code>. [https://phabricator.wikimedia.org/T285612] * A <code>REL1_45</code> branch for MediaWiki core and each of the extensions and skins in Wikimedia git has been created. This is the first step in the release process for MediaWiki 1.45.0, scheduled for late November 2025. If you are working on a critical bug fix or working on a new feature, you may need to take note of this change. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/ZUY7TY3Z6XPZWZVAZV63OPO5OW52Q6GE/] * The process for generating CirrusSearch dumps has been updated due to slowing performance. If you encounter any issues migrating to the replacement dumps, please contact the Search Platform Team for support. [https://phabricator.wikimedia.org/T366248][https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/3KQPOR6ACVN6OVLMLZPIBXQSWQKW4E3K/] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.2|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W46"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:38, 10 November 2025 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29606150 --> == Tech News: 2025-47 == <section begin="technews-2025-W47"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/47|Translations]] are available. '''Updates for editors''' * The [[mw:Special:MyLanguage/Readers/Reader Experience|Reader Experience team]] is experimenting with [[mw:Special:MyLanguage/Readers/Reader Experience/WE3.3.4_Reading lists|reading lists on mobile web]], allowing logged-in readers with no edits to save private lists of articles for later. The experiment is running on Arabic, Chinese, French, Indonesian, and Vietnamese Wikipedias since the week of 10 November, and will begin on English Wikipedia the week of 17 November. * Users who can’t receive their email verification code during login can now get help by submitting a form on a new special page. This update is part of the [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security|Account Security]] initiative. If your account has an email address, please make sure you still have access to it. When logging in from a new device or location without 2FA, you may be asked to enter a 6-digit code sent by email to finish logging in. [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security#Why are you requiring me to enter a code from my email to log in? Can I opt out of this?|Learn more]]. * One new wiki has been created: a {{int:project-localized-name-group-wikisource}} in [[d:Q13324|Minangkabau]] ([[s:min:|<code>s:min:</code>]]) [https://phabricator.wikimedia.org/T408317] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * As part of the [[mw:Special:MyLanguage/Parsoid/Parser Unification|Parser Unification]] project, the Content Transform Team rolled out Parsoid as the default parser to many low-traffic Wikipedias and is preparing the next step to high traffic ones. This message is an invitation for you to opt-in to Parsoid, as described in the [[mw:Special:MyLanguage/Help:Extension:ParserMigration|Extension:ParserMigration]] documentation, and identify any issues you might encounter with your own workflow using bots, gadgets, or user scripts. Please, let us know through the ''"Report Visual Bug"'' link in the Tools sidebar or create a phab ticket and tag the [[phab:project/view/5846|Content Transform Team in Phabricator]]. * Unsupported Tools: Several issues with [[:c:Special:MyLanguage/Commons:Video2commons|Video2Commons]] have been fixed, including filename-related upload failures, black-video imports, and retry handling. AV1 support has also been added. Ongoing work focuses on backend stability, ffmpeg errors, subtitle imports, metadata handling, and playlist uploads. To track specific tasks, check the [[phab:tag/video2commons/|Phabricator board]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.3|MediaWiki]] '''Meetings and events''' * Save the date for the next Wikimedia Hackathon happening in Milan, Italy from May 1–3, 2026. Registration will open in January 2026. [https://pretix.eu/wikimedia/Hackathon-2026/ Scholarship applications are currently open], and will close on November 28, 2025. If you have any questions, please email <bdi lang="en" dir="ltr">hackathon@wikimedia.org</bdi>. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/47|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W47"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:26, 17 November 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29627455 --> == Tech News: 2025-48 == <section begin="technews-2025-W48"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/48|Translations]] are available. '''Updates for editors''' * Last week, the [[mw:Special:MyLanguage/Wikimedia Search Platform|Wikimedia Search Team]] recreated the "DWIM" (Do What I Mean) gadget functionality server-side, for Russian and Hebrew Wikipedias. This feature adds cross-keyboard suggestions to the standard search-box suggestions. For example, searching for ''<span lang="und" dir="ltr">cxfcnmt</span>'' on Russian Wikipedia will now add suggestions for ''<span lang="ru" dir="ltr">счастье</span>'' ("happiness") that the user probably intended. They plan to enable this feature for other Russian and Hebrew wikis this week. [https://phabricator.wikimedia.org/T408734] * Later this week, users of the "{{int:codemirror-beta-feature-title}}" [[Special:Preferences#mw-prefsection-betafeatures|beta feature]] will have syntax highlighting available in [[mw:Special:MyLanguage/Help:DiscussionTools|DiscussionTools]]. This requires that the "{{int:discussiontools-preference-sourcemodetoolbar}}" preference be set. [https://phabricator.wikimedia.org/T407918] * [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|Campaign events extension]] – the set of tools for coordinating events and other on-wiki collaborations has now been deployed to all Wikimedia wikis. A new feature known as [[m:Special:MyLanguage/CampaignEvents/Collaborative contributions|Collaborative contribution]] to help organizers and participants see the impact of activities has also been added. Join the upcoming [[m:Special:MyLanguage/Event:Connection learning session 3|learning session]] to see the new feature in action and share your feedback. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:24}} community-submitted {{PLURAL:24|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the bug which stopped CodeReviewBot from working, has now been fixed. [https://phabricator.wikimedia.org/T410417] '''Updates for technical contributors''' * Users of Wikimedia API can join a usability study to help validate the new design of Wikimedia REST API sandboxes. Interested participants should fill the [https://wikimediafoundation.limesurvey.net/487662 recruitment survey]. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/IREJRRWTZTGCYWQHDMSNJFTQAEPOOAE3/] * The MediaWiki Interfaces team is deprecating XSLT stylesheets within the Action API. Support for <code dir=ltr>format=xml'''&xlst={stylesheet}'''</code> will be removed from Wikimedia projects by the end of November, 2025. In addition, it will soon be disabled by default in MediaWiki release versions: v1.43 (LTS), v1.44, and v1.45. Support for XSLT stylesheets will be fully removed from MediaWiki v1.46 (expected to release between April and May 2026). [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/5AX7UWAVVUNUSBOIRHMNOKWOZ5EZI3JX/] * The WDQS legacy endpoint ([https://query-legacy-full.wikidata.org/ query-legacy-full.wikidata.org]) will be decommissioned at the end of December 2025, and finally closed down on 7th January 2026. After this date, users should expect requests to query.wikidata.org that require the full graph to fail or return invalid results if they are not rewritten to use SPARQL federation. The team encourages users to ensure that tools and workflows use the supported WDQS endpoints (<span dir=ltr><nowiki>https://query.wikidata.org/</nowiki></span> - Main graph or <span dir=ltr><nowiki>https://query-scholarly.wikidata.org/</nowiki></span> - Scholarly graph). For support with migrating use cases, please review the [[d:Special:MyLanguage/Wikidata:Data_access|Data Access]] and [[d:Wikidata:Request_a_query|Request a Query]] pages for details and assistance on alternative access methods. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.4|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/48|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W48"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 15:56, 24 November 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29702226 --> == Tech News: 2025-49 == <section begin="technews-2025-W49"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/49|Translations]] are available. '''Updates for editors''' * The Wikipedia Year in Review 2025 will be available on December 2 for users of iOS and Android Wikipedia apps, featuring new personalized insights, updated reading highlights, and refreshed designs. Learn more on the review's [[mw:Special:MyLanguage/Wikimedia Apps/Team/Wikipedia Year in Review/Updates|project page]]. * The Growth team is working on improving the text and presentation of the Verification Email sent to new users to make them more welcoming, useful and informative. Some new text have been drafted for A/B testing and you can help by translating them. See [[phab:T396155|Phabricator]]. * [[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]] will now be deployed at Japanese, Urdu and Chinese Wikipedias on December 2. Add a link is based on a prediction model that suggests links to be added to articles. While this feature has already been available on most Wikipedias, the prediction model could not support certain languages. A new model has now been developed to handle these languages, and it will be gradually rolled out to other Wikipedias over time. If you would like to know more, please contact [[mw:user:Trizek (WMF)|Trizek (WMF)]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:34}} community-submitted {{PLURAL:34|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where search boxes on some Commons pages showed no results due to switch from SpecialSearch to MediaSearch, has now been fixed. [https://phabricator.wikimedia.org/T399476] * Two new wikis have been created: ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q36846|Toki Pona]] ([[w:tok:|<code>w:tok:</code>]]) [https://phabricator.wikimedia.org/T404457] ** a {{int:project-localized-name-group-wikiquote}} in [[d:Q33655|Nigerian Pidgin]] ([[q:pcm:|<code>q:pcm:</code>]]) [https://phabricator.wikimedia.org/T408318] '''Updates for technical contributors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.5|MediaWiki]] '''In depth''' * The Wikimedia Foundation is in the early stages of exploring approaches to '''Article guidance'''. The initiative aims to identify interventions that could help new editors easily understand and apply existing Wikipedia practices and policies when creating an article. The project is in the exploration and early experimental design phase. All community members are encouraged to [[mw:Special:MyLanguage/Article guidance|learn more]] about the project, and share their thoughts on [[mw:Special:MyLanguage/Talk:Article guidance|the talk page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/49|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W49"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:57, 1 December 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29732328 --> == Tech News: 2025-50 == <section begin="technews-2025-W50"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/50|Translations]] are available. '''Weekly highlight''' * Anybody who wishes to secure their user account can now use [[m:Special:MyLanguage/Help:Two-factor authentication|two-factor authentication]] (2FA). This is available to all registered users of all Wikimedia projects. This is part of the [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security|Account Security]] initiative. Later, 2FA will be required for all users who can take security- or privacy-sensitive actions. '''Updates for editors''' * Following last week's deployments, the [[mw:Special:MyLanguage/Help:Growth/Tools/Add a link|Add a link]] feature, which allows editors to add suggested links during editing, will be available to an additional [[Phab:T410469|33 Wikipedias]] starting on 9 December. This expansion is possible thanks to the new prediction model that now supports all languages, including those that were previously not covered. While the feature has been available on most Wikipedias for some time, this rollout brings us closer to using the improved model everywhere. If you have any questions or would like more details please contact [[mw:user:Trizek (WMF)|Trizek (WMF)]]. * Last week, the [[mw:Special:MyLanguage/Wikimedia Search Platform|Search Platform team]] added [[w:en:Transliteration|transliterated]] as-you-type search suggestions to Georgian wikis. If there are only a few regular search suggestions, then queries in Latin or Cyrillic script [[phab:T127003|are now rewritten into Georgian script]] to look for more matches. For example, searching for either <bdi lang="ka-Latn" dir="ltr">''bedniereba''</bdi> or <bdi lang="ka-Cyrl" dir="ltr">''бедниереба''</bdi> will now suggest the existing article about <bdi lang="ka" dir="ltr">ბედნიერება</bdi> ("happiness"). You can recommend other languages where transliterated suggestions would be useful [[phab:T375215|on Phabricator]] for future development. * Later this week, a controlled experiment will begin for editors on the 100 largest Wikipedias who are editing a section in the mobile web visual editor. 50% of these editors will notice a new "Edit full page" button that will enable them to expand their editing session to the whole page. This feature is intended to make it easier for people on mobile web to edit any article section, regardless of which section-edit icon they tapped to begin. The experiment will last ~4 weeks. You can find [[phab:T409112|more details]] about the project. * Later this week, the [[mw:Special:MyLanguage/Readers/Reader Growth|Reader Growth team]] will launch a [[mw:Special:MyLanguage/Readers/Reader Growth/WE3.1.14 Expanded Mobile Sections|mobile web experiment]] to expand all article sections by default (currently they are collapsed by default) and pin the section header the user is currently reading to the top of the page. The experiment will affect 10% of users on Arabic, Chinese, French, Indonesian, and Vietnamese Wikipedias. [https://phabricator.wikimedia.org/T409485] * The [[mw:Special:MyLanguage/Wikimedia Apps/Team/Wikipedia Year in Review/2025 Year in Review|Wikipedia Year in Review 2025]], a feature in the Wikipedia mobile apps (iOS and Android) that provides users with a personalised summary of their engagement with Wikipedia over the year, is now available on the iOS and Android apps. This edition includes expanded personalised insights, improved reading highlights, new donor messaging, and updated designs. Open the app to view your Year in Review and explore your reading journey from 2025. * A recent software bug caused edits made with VisualEditor to make unintended changes to wikitext, including removing whitespace and replacing spaces with underscores in wikilinks inside citations. This was partially fixed last week, and further fixes are in progress. Editors who used VisualEditor between November 28 and December 2 should review their edits for unexpected modifications. [https://phabricator.wikimedia.org/T411238] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the incorrect handling of URLs copied from the address bar of Microsoft Edge users, has been resolved. [https://phabricator.wikimedia.org/T341281] '''Updates for technical contributors''' * Starting this week, users of the "{{int:codemirror-beta-feature-title}}" [[Special:Preferences#mw-prefsection-betafeatures|beta feature]] will have [[mw:Special:MyLanguage/Help:Extension:CodeMirror|CodeMirror]] as the editor for Lua, JavaScript, CSS, JSON and Vue content models, instead of [[mw:Special:MyLanguage/Extension:CodeEditor|CodeEditor]]. With this, the [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Linting|linters]] will be upgraded. This is part of a larger effort to eventually replace CodeEditor and provide a consistent code editing experience. [https://phabricator.wikimedia.org/T373711] * Developers are encouraged to take the [https://wikimediafoundation.limesurvey.net/552643 2025 Developer Satisfaction Survey], which remains open until 5 January 2026. If you build software for the Wikimedia ecosystem and would like to share your experiences or feedback, your participation is greatly appreciated. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/W4WBKO6Q55UWWCCSFWQATKEXBEHP3QNR/] * There is no new MediaWiki version this week. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/50|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W50"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:45, 8 December 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29738112 --> == Tech News: 2025-51 == <section begin="technews-2025-W51"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/51|Translations]] are available. '''Updates for editors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:18}} community-submitted {{PLURAL:18|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, one of the fixes addressed an issue for temporary accounts adding an external URL, which triggered an hCaptcha request in more cases than intended, and did not display the required popup on the first attempt to publish the edit. [https://phabricator.wikimedia.org/T411927] '''Updates for technical contributors''' * To improve database and site performance, external links to Wikimedia projects will no longer be stored in the database. This means they will not be searchable in [[{{#special:LinkSearch}}]], will not be checked by the Spam Blacklist or AbuseFilter as new links, and will not be in the <code dir=ltr>externallinks</code> table on database replicas. In the future this may be extended to other highly-linked trusted websites on a per-wiki basis, such as Creative Commons links on Wikimedia Commons. [https://phabricator.wikimedia.org/T405005] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.7|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/51|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W51"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:03, 15 December 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29796010 --> == Tech News: 2025-52 == <section begin="technews-2025-W52"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2025/52|Translations]] are available. '''Updates for editors''' * From January, edit filters [[mw:Special:MyLanguage/Extension:AbuseFilter/Access flags|can be set]] to automatically suppress their details such as rules and list of attempted edits and actions. This will help oversighters use edit filters to prevent doxxing or other suppressible material. [https://phabricator.wikimedia.org/T290324] * The next issue of Tech News will be sent out on 12 January 2026 because of the end of year holidays. Thank you to all of the translators, and people who submitted content or feedback, this year. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:16}} community-submitted {{PLURAL:16|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the crash that occurred when tapping "First Steps" in the Wikipedia Android Year in Review has now been fixed, and the feature opens as expected. [https://phabricator.wikimedia.org/T411546] '''Updates for technical contributors''' * Interface elements such as diffs and categories generated by MediaWiki used to have the attribute <code dir=ltr>data-mw="interface"</code> to distinguish from wiki content. The attribute has been replaced with <code dir=ltr>data-mw-interface=""</code>, to avoid potential conflicts with other <code dir=ltr>data-mw</code> attributes, which are generated by Parsoid. [https://phabricator.wikimedia.org/T409187] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] There is no new MediaWiki version this week or next week. '''Meetings and events''' * The [[mw:Wikimedia Hackathon Northwestern Europe 2026|Wikimedia Hackathon Northwestern Europe 2026]] will take place on 13-14 March 2026 in Arnhem, the Netherlands. Applications just opened mid-December and will close in mid-January or earlier if capacity is reached. With space for approximately 100 participants, early application is encouraged. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2025/52|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2025-W52"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:45, 22 December 2025 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29831856 --> == Tech News: 2026-03 == <section begin="technews-2026-W03"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/03|Translations]] are available. '''Weekly highlight''' * The Wikimedia Foundation has shared some guiding questions for the July 2026–June 2027 Annual Plan on [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2026-2027/Product & Technology OKRs|Meta]] and ''[[diffblog:2025/12/10/shaping-wikimedia-foundations-2026-2027-annual-goals-key-questions-for-the-wikimedia-movement/|Diff]]''. These focus on global trends, faster and healthier experimentation, better support for newcomers, strengthening editors and advanced users, improving collaboration across projects, and growing and retaining readership. Feedback and ideas are welcome on the [[m:Talk:Wikimedia Foundation Annual Plan/2026-2027|talk page]]. '''Updates for editors''' * As part of the current work of Community Tech team on the [[m:Special:MyLanguage/Community Wishlist/W372|Multiple watchlists]] project, the display of [[Special:EditWatchlist|EditWatchlist]] will be updated as a first step towards multiple watchlists. Additionally, the pagination on [[Special:Search|Search]] will be updated too, as a part of the work on the [[m:Special:MyLanguage/Community Wishlist/W186|Revamp pagination / page navigation]] wish. [https://phabricator.wikimedia.org/T411596] * [[m:Special:GlobalWatchlist|The Global Watchlist]] is a MediaWiki [[mw:Special:MyLanguage/Extension:GlobalWatchlist|extension]] that lets you see your watchlists from different wikis on the same page. It was recently updated to look more like the regular [[Special:Watchlist|Watchlist]], such as preparing it for temporary accounts in IP masking (including rerouting user links to contributions pages), making page titles bold, and opening links in edit summaries and tags in new browser tabs. [https://phabricator.wikimedia.org/T398361][https://phabricator.wikimedia.org/T298919][https://phabricator.wikimedia.org/T273526][https://phabricator.wikimedia.org/T286309] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where global blocks did not have the option to disable sending emails, has now been fixed, and will be available for use in the week of January 13. [https://phabricator.wikimedia.org/T401293] '''Updates for technical contributors''' * The [[mw:Special:MyLanguage/VisualEditor/Citation tool|VisualEditor citation tool]] and [[mw:Special:MyLanguage/Help:Reference Previews|Reference Previews]] now support "map" as a reference type. [https://phabricator.wikimedia.org/T411083] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.10|MediaWiki]]/[[mw:MediaWiki 1.46/wmf.11|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/03|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W03"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:33, 12 January 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29907192 --> == Tech News: 2026-04 == <section begin="technews-2026-W04"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/04|Translations]] are available. '''Updates for editors''' * The tray shown on [[Special:Diff|Special:Diff]] in mobile view has been redesigned. It is now collapsed by default, and incorporates a link to undo the edit being viewed, making it easier for mobile editors and reviewers to take action while keeping the interface uncluttered. [https://phabricator.wikimedia.org/T402297] * [[m:Special:GlobalWatchlist|The Global Watchlist]] lets you view your watchlists from multiple wikis on one page. The [[mw:Special:MyLanguage/Extension:GlobalWatchlist|extension]] continues to improve — it now automatically determines the text direction (ensuring correct display of sites with unusual domain names) and shows detailed descriptions for log actions. Later this week, a new permanent link for page creations and CSS classes for each entry element will be added. [https://phabricator.wikimedia.org/T412505][https://phabricator.wikimedia.org/T287929][https://phabricator.wikimedia.org/T262768][https://phabricator.wikimedia.org/T414135] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:32}} community-submitted {{PLURAL:32|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the previously observed issue in Vector 2022, where anchor link targets were obscured by the sticky header, has now been addressed. [https://phabricator.wikimedia.org/T406114] '''Updates for technical contributors''' * As mentioned in the [[m:Special:MyLanguage/Tech/News/2025/44|October 2025 deprecation announcement]], MediaWiki Interfaces team will begin sunsetting all transform endpoints containing a trailing slash from the MediaWiki REST API the week of January 26. Changes are expected to roll out to all wikis on or before January 30th. All API users currently calling them are encouraged to transition to the non-trailing slash versions. Both endpoint variations can be found, compared, and tested using the [https://test.wikipedia.org/wiki/Special:RestSandbox REST Sandbox]. If you have questions or encounter any problems, please file a ticket in Phabricator to the [https://phabricator.wikimedia.org/project/view/6931/ #MW-Interfaces-Team board]. * Interactive reference documentation for the [[mw:Special:MyLanguage/Wikimedia REST API|Wikimedia REST API]] has moved. Requests to API docs previously hosted through [[mw:Special:MyLanguage/RESTBase|RESTBase]] (e.g.: <code dir=ltr>https://en.wikipedia.org/api/rest_v1/</code>) are now redirected to the [[w:en:Special:RestSandbox|REST Sandbox]]. * The [[mw:Special:MyLanguage/Wikidata Platform|WMF Wikidata Platform team]] (WDP) has published its [[d:Special:MyLanguage/Wikidata:Wikidata Platform team/Newsletter|January 2026 newsletter]]. It includes updates on the legacy full-graph endpoint decommissioning, the User-Agent policy change, the monthly Blazegraph migration office hours, and efforts to reduce regressions caused by the legacy endpoint shutdown. As a reminder, you can [[m:Special:MyLanguage/Global message delivery/Targets/WDP team updates|subscribe to the WDP newsletter]]! * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.12|MediaWiki]] '''Meetings and events''' * The [[mw:Wikimedia Hackathon Northwestern Europe 2026|Wikimedia Hackathon Northwestern Europe 2026]] will take place on 13-14 March 2026 in Arnhem, the Netherlands. Applications opened mid-December and will close soon or when capacity is reached. It's a two-day, technically oriented hackathon bringing together Wikimedians from the region. Hope to see you there! '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/04|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W04"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:29, 19 January 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29943403 --> == Tech News: 2026-05 == <section begin="technews-2026-W05"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/05|Translations]] are available. '''Updates for editors''' * Wikimedia Foundation invites comments on [[m:Special:MyLanguage/Product and Technology Advisory Council/Year1 Reflections and Proposed Way Forward 2026 Update|proposed future]] of the [[:m:Special:MyLanguage/Product and Technology Advisory Council|Product and Technology Advisory Council]] until 28 February. * All users with registered accounts can now use passkeys for [[m:Special:MyLanguage/Help:Two-factor authentication|two-factor authentication]] (2FA). Passkeys are a simple way to log in without using a second device. They verify the user's identity using a fingerprint, face scan, or a PIN code. To set up a passkey, first set up a regular 2FA method. Currently, to log in with a passkey, users must also use a password. Later this quarter, passwordless login will allow users to log in with a single click and a passkey. Users with advanced rights will also be required to have 2FA enabled. This is part of the [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security|Account Security]] project. * Unregistered contributors on blocked IPs or blocked IP ranges can now interact on-wiki to appeal a block by creating a temporary account to appeal a block on the user talk page, unless the "prevent this user from editing their own talk page" is enabled. This solves the problem of logged-out users unable to use the default unblock process via user talk page. [https://phabricator.wikimedia.org/T398673] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the Two-Factor Authentication (2FA) methods description on the management page has been updated. It is now clearer and easier for users to understand and make use of. [https://phabricator.wikimedia.org/T332385] '''Updates for technical contributors''' * A new AbuseFilter variable, <code>account_type</code>, has been added to provide a reliable way to determine the account type being created in the <code>createaccount</code> and <code>autocreateaccount</code> actions. As part of this change, the variable <code>accountname</code> has been renamed to <code>account_name</code>, and <code>accountname</code> is now deprecated. Edit filter managers should update any filters that use hardcoded account type checks or the deprecated variable. [https://phabricator.wikimedia.org/T414049] * Image thumbnails that are requested in non-standard sizes, and using non-standard methods such as direct requests to <code dir=ltr><nowiki>upload.wikimedia.org/…</nowiki></code> will stop working in the near future. This change is to prevent ongoing external abuse by web-scrapers and bots. Some users with custom CSS/JS, Interface Admins who can fix gadgets and local skins, and Tool-authors, will need to update their code to use standard thumbnail sizes. [[phab:T414805|Details, search-links, and examples of how to fix them, are available in the task]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.13|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/05|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W05"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:17, 26 January 2026 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=29969530 --> == Tech News: 2026-06 == <section begin="technews-2026-W06"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/06|Translations]] are available. '''Updates for editors''' * The "{{int:pageinfo-toolboxlink}}" feature, which gives validating information about a page ([{{fullurl:{{FULLPAGENAME}}|action=info}} example]), now automatically includes a table of contents. If there is a local [[{{ns:8}}:Pageinfo-header]] page created by individual users, it can now be removed. [https://phabricator.wikimedia.org/T363726] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:21}} community-submitted {{PLURAL:21|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, VisualEditor previously added bold or italic formatting inside link descriptions, making the wikicode complex. This has now been fixed. [https://phabricator.wikimedia.org/T409669] '''Updates for technical contributors''' * There was no XML dump on 20 January. Additionally, from now on, dumps will be generated once per month only. [https://phabricator.wikimedia.org/T414389] * The MediaWiki Interfaces team removed support for all transform endpoints containing a trailing slash from the [https://www.mediawiki.org/wiki/Special:MyLanguage/API:REST%20API MediaWiki REST API]. All API users currently calling those endpoints are encouraged to transition to the non-trailing slash versions. If you have questions or encounter any problems, please file a ticket in phabricator to the [https://phabricator.wikimedia.org/project/view/6931/ #MW-Interfaces-Team board]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.14|MediaWiki]] '''Weekly highlight''' * Users are reminded that the Wikimedia Foundation has shared some guiding questions for the July 2026–June 2027 Annual Plan on [[m:Special:MyLanguage/Wikimedia Foundation Annual Plan/2026-2027/Product & Technology OKRs|Meta]] and ''[[diffblog:2025/12/10/shaping-wikimedia-foundations-2026-2027-annual-goals-key-questions-for-the-wikimedia-movement/|Diff]]''. These focus on global trends, faster and healthier experimentation, better support for newcomers, strengthening editors and advanced users, improving collaboration across projects, and growing and retaining readership. Feedback and ideas are welcome on the [[m:Talk:Wikimedia Foundation Annual Plan/2026-2027|talk page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/06|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W06"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:43, 2 February 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30000986 --> == Tech News: 2026-07 == <section begin="technews-2026-W07"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/07|Translations]] are available. '''Updates for editors''' * [[File:Maki-gift-15.svg|12px|link=|class=skin-invert|Wishlist item]] Logged-in contributors who manage large or complex watchlists can now organise and filter watched pages in ways that improve their workflows with the new [[mw:Special:MyLanguage/Help:Watchlist labels|Watchlist labels]] feature. By adding custom labels (for example: pages you created, pages being monitored for vandalism, or discussion pages) users can more quickly identify what needs attention, reduce cognitive load, and respond more efficiently. This improves watchlist usability, especially for highly active editors. * A new feature available on [[Special:Contributions|Special:Contributions]] shows [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts|temporary accounts]] that are likely operated by the same person, and so makes patrolling less time-consuming. Upon checking contributions of a temporary account, users with access to temporary account IP addresses can now see a view of contributions from the related temporary accounts. The feature looks up all the IPs associated with a given temporary account within the data retention period and shows all the contributions of all temporary accounts that have used these IPs. [[mw:Special:MyLanguage/Trust and Safety Product/Temporary Accounts#February 2026: Improvements to the patroller tooling|Learn more]]. [https://phabricator.wikimedia.org/T415674] * When editors preview a wikitext edit, the reminder box that they are only seeing a preview (which is shown at the top), now has a grey/neutral background instead of a yellow/warning background. This makes it easier to distinguish preview notes from actual warnings (for example, edit conflicts or problematic redirect targets), which will now be shown in separate warning or error boxes. [https://phabricator.wikimedia.org/T414742] * The [[m:Special:GlobalWatchlist|Global Watchlist]] lets you view your watchlists from multiple wikis on one page. The [[mw:Special:MyLanguage/Extension:GlobalWatchlist|extension]] continues to improve — it now properly supports more than one Wikibase site, for example both [[d:|Wikidata]] and [[testwikidata:|testwikidata]]. In addition, issues regarding text direction have been fixed for users who prefer Wikidata or other Wikibase sites in right-to-left (RTL) languages. [https://phabricator.wikimedia.org/T415440][https://phabricator.wikimedia.org/T415458] * The automatic "magic links" for ISBN, RFC, and PMID numbers have been [[mw:Special:MyLanguage/Help:Magic links|deprecated in wikitext since 2021]] due to inflexibility and difficulties with localization. Several wikis have successfully replaced RFC and PMID magic links with equivalent external links, but a template was often required to replace the functionality of the ISBN magic link. There is now a new [[mw:Special:MyLanguage/Help:Magic words#isbn|built-in parser function]] <code dir=ltr><nowiki>{{#isbn}}</nowiki></code> available to replace the basic functionality of the ISBN magic link. This makes it easier for wikis who wish to migrate off of the deprecated magic link functionality to do so. [https://phabricator.wikimedia.org/T145604] * Two new wikis have been created: ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q35401|Jju]] ([[w:kaj:|<code>w:kaj:</code>]]) [https://phabricator.wikimedia.org/T413283] ** a {{int:project-localized-name-group-wikipedia}} in [[d:Q1186896|Nawat]] ([[w:ppl:|<code>w:ppl:</code>]]) [https://phabricator.wikimedia.org/T413273] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * A new global user group has been created: [[{{int:grouppage-local-bot}}|{{int:group-local-bot}}]]. It will be used internally by the software to allow community bots to bypass rate limits that are applied to abusive [[w:en:Web scraping|web scrapers]]. Accounts that are approved as bots on at least one Wikimedia wiki will be automatically added to this group. It will not change what user permissions the bot has. [https://phabricator.wikimedia.org/T415588] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.15|MediaWiki]] '''Meetings and events''' * The [[mw:Special:MyLanguage/MediaWiki Users and Developers Conference Spring 2026|MediaWiki Users and Developers Conference, Spring 2026]] will be held March 25–27 in Salt Lake City, USA. This event is organized by and for the third-party MediaWiki community. You can propose sessions and register to attend. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/AZBWVI46SDEB65PGR5J6E4TYOQQEZXM7/] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/07|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W07"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 23:30, 9 February 2026 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30026671 --> == Tech News: 2026-08 == <section begin="technews-2026-W08"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/08|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Wikimedia Site Reliability Engineering|SRE Team]] will be performing a cleanup of Wikimedia's [[m:Special:MyLanguage/Etherpad|Etherpad]] instance, the web-based editor for real-time collaborative document editing. All pads will be permanently deleted after 30 April, 2026 – if there are still migration projects in progress at that point the team can revisit the date on a case by case basis. Please create local backups of any content you wish to keep, as deleted data cannot be recovered. This cleanup helps reduce database size and minimize infrastructure footprint. Etherpad will continue to support real-time collaboration, but long-term storage should not be expected. Additional cleanups may occur in the future without prior notice. [https://phabricator.wikimedia.org/T415237] '''Updates for editors''' * The Information Retrieval team will be launching an [[mw:Special:MyLanguage/Readers/Information Retrieval/Phase 1|Android mobile app experiment]] that tests hybrid search capabilities which can handle both semantic and keyword queries. The improvement of on-platform search will enable readers to find what they’re looking for directly on Wikipedia more easily. The experiment will first be launched on Greek Wikipedia in late February, followed by English, French, and Portuguese in March. [https://diff.wikimedia.org/2026/01/08/semantic-search-making-it-easier-to-find-the-information-readers-want/ Read more] on Diff blog. [https://www.mediawiki.org/wiki/Readers/Information_Retrieval] * The Reader Growth team will run [[mw:Special:MyLanguage/Readers/Reader Growth/WE3.10.2 Mobile Table of Contents|an experiment]] for mobile web users, that adds a table of contents and automatically expands all article sections, to learn more about navigation issues they face. The test will be available on Arabic, Chinese, English, French, Indonesian, and Vietnamese Wikipedias. * Previously, site notices ([[{{ns:8}}:Sitenotice]] and [[{{ns:8}}:Anonnotice]]) would only render on the desktop site. Now, they will render on all platforms. Users on mobile web will now see these notices and be informed. Site administrators should be prepared to test and fix notices on mobile devices to avoid interference with articles. To opt out, interface admins can add <code dir="ltr">#siteNotice { display: none; }</code> to [[{{ns:8}}:Minerva.css]]. [https://phabricator.wikimedia.org/T138572][https://phabricator.wikimedia.org/T416644] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:19}} community-submitted {{PLURAL:19|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue on [[Special:RecentChanges|Special:RecentChanges]] has been fixed. Previously, clicking hide in the active filters caused the "view new changes since…" button to disappear, though it should have remained visible. The button now behaves as expected. [https://phabricator.wikimedia.org/T406339] '''Updates for technical contributors''' * New documentation is now available to help editors debug on-site search features. It supports troubleshooting when pages do not appear in results, when ranking seems unexpected, and when you need to inspect what content is being indexed, helping make search behavior easier to understand and analyze. [[mw:Help:CirrusSearch/Debug|Learn more]]. [https://phabricator.wikimedia.org/T411169] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.16|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/08|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W08"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:17, 16 February 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30086330 --> == Tech News: 2026-09 == <section begin="technews-2026-W09"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/09|Translations]] are available. '''Weekly highlight''' * [[mw:Special:MyLanguage/Edit check/Reference Check|Reference Check]] has been deployed to English Wikipedia, completing its rollout across all Wikipedias. The feature prompts newcomers to add a citation before publishing new content, helping reduce common citation-related reverts and improve verifiability. In A/B testing, the impact was substantial: newcomers shown Reference Check were approximately 2.2 times more likely to include a reference on desktop and about 17.5 times more likely on mobile web. [https://analytics.wikimedia.org/published/reports/editing/reference_check_ab_test_report_final_2025.html] '''Updates for editors''' * The [[mw:Special:MyLanguage/Extension:InterwikiSorting|InterwikiSorting extension]], which allowed for the [[m:Special:MyLanguage/Interwiki sorting order|sorting of interwiki links]], has been undeployed from Wikipedia. As a result, editors who had enabled interwiki link sorting in non-compact mode (full list format) will now see links reordered. The links moving forward will be listed in the alphabetical order of language code. [https://phabricator.wikimedia.org/T253764] * Later this week, people who are editing a page-section using the mobile visual editor, will notice a new "Edit full page" button. When tapped, you will be able to edit the entire article. This helps when the change you want to make is outside the section you initially opened. [https://phabricator.wikimedia.org/T387175][https://phabricator.wikimedia.org/T409112] * [[mw:Special:MyLanguage/Readers/Reader Experience|The Reader Experience team]] is inviting editors to assess whether dark mode should still be considered "beta" on their wiki, based on their experience of how well it functions on desktop and mobile. If the feature is deemed mature, editors can update the interface messages in <code dir=ltr>MediaWiki:skin-theme-description</code> and <code dir=ltr>MediaWiki:Vector-night-mode-beta-tag</code> to indicate that dark mode is ready and no longer considered beta. * The improved [[mw:Wikimedia_Apps/Team/iOS/Activity_Tab|Activity tab]] which displays user-insights is now available to all users of the Wikipedia iOS app (version 7.9.0 and later). Following earlier A/B testing that showed higher account creation among users with access to the feature, it has been rolled out to 100% of users along with some updates. The Activity tab now shows your edited articles in the timeline, offers editing impact insights like contribution counts and article view trends, and customization options to improve in-app experience for users. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:21}} community-submitted {{PLURAL:21|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, a bug that prevented [[mw:Special:MyLanguage/Extension:DiscussionTools|DiscussionTools]] from working on mobile has now been fixed, restoring full functionality. [https://phabricator.wikimedia.org/T415303] '''Updates for technical contributors''' * The [[m:Special:GlobalWatchlist|Global Watchlist]] lets you view your watchlists from multiple wikis on one page. The [[mw:Special:MyLanguage/Extension:GlobalWatchlist|extension]] that makes this possible continues to improve. The latest upgrade is the inclusion of a [[mw:Extension:GlobalWatchlist#hook|new hook]], <code dir=ltr>ext.globalwatchlist.rebuild</code>, which fires after each watchlist rebuild. This allows you to run gadgets and user scripts for the Special page. [https://phabricator.wikimedia.org/T275159] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.17|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/09|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W09"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:03, 23 February 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30119102 --> == Tech News: 2026-10 == <section begin="technews-2026-W10"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/10|Translations]] are available. '''Weekly highlight''' * Wikipedia 25 [[m:Special:MyLanguage/Wikipedia 25/Easter egg experiments|Birthday mode]] is now live on Betawi, Breton, Chinese, Czech, Dutch, English, French, Gorontalo, Indonesian, Italian, Luxembourgish, Madurese, Sicilian, Spanish, Thai, and Vietnamese Wikipedias! This limited-time campaign feature celebrates 25 years of Wikipedia with a birthday mascot, Baby Globe. When turned on, Baby Globe is shown on [[m:Special:MyLanguage/Wikipedia 25/Easter egg experiments/article configuration|~2,500 articles]], waiting to be discovered by readers. Communities can choose to turn Birthday mode on by getting consensus from their community and asking an admin to enable the feature and customize it via [[m:Special:MyLanguage/Wikipedia 25/Easter egg experiments#Community Configuration Demo|community configuration]] on the local wiki. '''Updates for editors''' * [[:m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|Sub-referencing]], a new feature to re-use references with different details has been released to Swedish Wikipedia, Polish Wikipedia and [[:phab:T418209|a couple of other wikis]]. You can [[:m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#test|try the feature]] on these projects or on testwiki and [https://en.wikipedia.beta.wmcloud.org/wiki/Sub-referencing betawiki]. Learnings from the first pilot wiki German Wikipedia have been [[:m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing/Learnings|published in a report]]. Reach out to the Wikimedia Deutschland team if you are [[:m:Talk:WMDE Technical Wishes/Sub-referencing#Pilot wikis|interested in becoming a pilot wiki]]. * [[mw:Special:MyLanguage/Help:Edit check#Paste check|Paste Check]] will become available at all Wikipedias this week. The feature prompts newcomers who are pasting text they are not likely to have written into VisualEditor to consider whether doing so risks a copyright violation. Paste Check [[mw:Special:MyLanguage/Edit check/Tags|tags]] all edits where it is shown for potential review. Local administrators can configure various aspects of the feature via [[{{#special:EditChecks}}]]. [[mw:Special:MyLanguage/Edit check/Paste Check#A/B Experiment|Research]] across 22 wikis found that Paste Check resulted in an 18% decrease in relative reverted-edits compared to the control group. Translators can [https://translatewiki.net/w/i.php?title=Special%3ATranslate&group=ext-visualeditor-ve-mw-editcheck&filter=&optional=1&action=translate help to localize] this and related features. * The [[mw:Special:MyLanguage/Readers/Reader Experience|Reader Experience team]] will be standardizing the user menu in the top right for all mobile users so that it is closer to the desktop experience. Currently this user menu is only visible to users with Advanced Mobile Controls (AMC) turned on. The only change is that a couple buttons previously in the left-side menu will move to the top right for users who do not have AMC turned on. This change is expected to go out March 9 and seeks to improve the user interface. [https://phabricator.wikimedia.org/T413912] * Starting in the week of March 2, the emails sent out when an email address was added, removed, or changed for an account will switch to a substantially nicer and clearer HTML email from the prior plaintext one. [https://phabricator.wikimedia.org/T410807] * Notifications are currently limited to 2,000 historic entries per user, and extend back to 2013 when the feature was released. This is going to be changed to only store Notifications from the last 5 years, but up to 10,000 of them. This will help with long-term infrastructure health and help to prevent more recent notifications from disappearing too soon. [https://phabricator.wikimedia.org/T383948] * The [[m:Special:GlobalWatchlist|Global Watchlist]] which lets you view your watchlists from multiple wikis on a single page continues to see improvements. The latest update improves label usage experience. The [[mw:Special:MyLanguage/Extension:GlobalWatchlist|extension]] now allows activating the [[mw:Special:MyLanguage/Manual:Language#Fallback languages|language fallback system]] for Wikidata items without labels in the viewed language, and showing those labels in the user’s preferred Wikidata language if no <code dir=ltr>uselang=</code> URL parameter is provided. [https://phabricator.wikimedia.org/T373686][https://phabricator.wikimedia.org/T416111] * The Wikipedia Android team has started a beta test of [[mw:Special:MyLanguage/Readers/Information Retrieval/Phase 1|hybrid search]] on Greek Wikipedia. Hybrid search capabilities can handle both semantic and keyword queries enabling readers to find what they’re looking for directly on Wikipedia more easily. * For security reasons, members of certain user groups are [[m:Special:MyLanguage/Mandatory two-factor authentication for users with some extended rights|required to have two-factor authentication]] (2FA) enabled. Currently, 2FA is required to use the group, but not to be a member of it. Given that this model still has some vulnerabilities, the situation will [[phab:T418580|gradually change in March]]. Members of these groups will be unable to disable last 2FA method on their account, and it will be impossible to add users without 2FA to these groups. Users will still be able to add new authentication methods or remove them, as long as at least one method is continuously enabled. In the second half of March, users without 2FA will be removed from these groups. This applies to: CentralNotice administrators, checkusers, interface administrators, suppressors, Wikidata staff, Wikifunctions staff, WMF Office IT and WMF Trust & Safety. Nothing will change for other users. See the linked task for deployment schedule. [https://phabricator.wikimedia.org/T418580] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue preventing users from creating an instance in [https://www.wikibase.cloud/ Wikibase.cloud] has now been fixed. [https://phabricator.wikimedia.org/T416807] '''Updates for technical contributors''' * To help ensure [[mw:Special:MyLanguage/MediaWiki Product Insights/Responsible Reuse|fair use of infrastructure]], over the next month the Wikimedia Foundation will implement global API rate limits across our APIs. In early March, stricter limits will be applied to unidentified requests from outside Toolforge/WMCS and API requests that are made from web browsers. In April, higher limits will be applied to identified traffic. These limits are intentionally set as high as possible to minimise impact on the community. Bots running in Toolforge/WMCS or with the bot user right on any wiki should not be affected for now. However, all developers are advised to follow updated best practices. For more information, see [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits|Wikimedia APIs/Rate limits]]. * The Wikidata Query Service Linked Data Fragment (LDF) endpoint will be decommissioned in February. This endpoint served limited traffic, which was successfully migrated to other data access methods that were better suited to support existing use cases. The hardware used to support the LDF endpoint will be reallocated to support the ongoing backend migration efforts. [https://phabricator.wikimedia.org/T415696] * The new Parsoid parser [[mw:Special:MyLanguage/Parsoid/Parser Unification/Updates|continues to be deployed to additional wikis]], improving platform sustainability and making it easier to introduce new reading and editing features. Parsoid is now the default parser on 488 WMF wikis (268 Wikipedias), now covering more than 10% of all Wikipedia page views. * The process and criteria for [[Special:MyLanguage/Wikimedia Enterprise#Access|requesting exceptional access]] to the high volume feed of the ''Wikimedia Enterprise'' APIs (at no cost for mission-aligned usecases), [[m:Talk:Wikimedia Enterprise#Exceptional access criteria|have now been published]]. This is to provide more thorough and clearer documentation for users. * [https://techblog.wikimedia.org/ Tech Blog], the blog dedicated to the Wikimedia technical community [https://techblog.wikimedia.org/2026/02/24/a-tech-blog-diff/ will be migrating] to [[diffblog:|Diff]], the community news and event blog. The migration should be complete in April 2026, after which new posts will be accepted for publishing. Readers will be able to access posts – old and new – on the landing page at https://diff.wikimedia.org/techblog. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.18|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/10|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W10"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 17:51, 2 March 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30137798 --> == Tech News: 2026-11 == <section begin="technews-2026-W11"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/11|Translations]] are available. '''Weekly highlight''' * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on Wednesday, 25 March 2026 at [https://zonestamp.toolforge.org/1774450800 15:00 UTC]. This is for the datacenter server switchover backup tests, [[wikitech:Deployments/Yearly calendar|which happen twice a year]]. During the switchover, all Wikimedia website traffic is shifted from one primary data center to the backup data center to test availability and prevent service disruption even in emergencies. * Last week, all wikis had 2 hours of read-only time, and extended unavailability for user-scripts and gadgets. This was due to a security incident which has since been resolved. Work is ongoing to prevent re-occurrences. For current information please see the [[m:Steward's noticeboard#Statement on Meta about today's user script security incident|post on the Stewards' noticeboard]] ([[m:Special:MyLanguage/Wikimedia Foundation/Product and Technology/Product Safety and Integrity/March 2026 User Script Incident|translations]]). '''Updates for editors''' * Users facing multiple blocks on mobile will now see the reasons for each block separately, instead of a generic message. This helps them understand why they are blocked and what steps they can take to resolve the issue. For example, users affected for using common VPNs (such as [[Special:MyLanguage/Apple iCloud Private Relay|iCloud Private Relay]]) will receive clearer guidance on what they need to do to start editing again. [https://phabricator.wikimedia.org/T357118] * Later this week, [[mw:Special:MyLanguage/VisualEditor/Suggestion Mode|Suggestion Mode]] will become available as a beta feature within the visual editor at all Wikipedias. This feature proactively suggests various types of actions that people can consider taking to improve Wikipedia articles, and learn about related guidelines. The feature is locally configurable, and can also be locally expanded with custom Suggestions. Current settings can be seen at [[Special:EditChecks]] and there are [[mw:Special:MyLanguage/Help:Suggestion mode#For administrators %E2%80%93 local customization|instructions for how administrators can customize]] the links to point to local guidelines. The feature is connected to [[mw:Special:MyLanguage/Help:Edit check|Edit check]] which suggests improvements while someone is writing new content. In the future, the Editing team plans to evaluate the feature's impact with newcomers through a controlled experiment. [https://phabricator.wikimedia.org/T404600] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where the cursor became misaligned during the use of CodeMirror’s syntax highlighting, which makes wikitext and code easier to read, has now been fixed. This problem specifically affected users who defined a font rule in a custom stylesheet while creating a new topic with DiscussionTools. [https://phabricator.wikimedia.org/T418793] '''Updates for technical contributors''' * API rate limiting update: To help ensure [[mw:Special:MyLanguage/MediaWiki Product Insights/Responsible Reuse|fair use of infrastructure]], global API rate limits will be applied this week to requests without a compliant User-Agent that originate from outside Toolforge/WMCS and to unauthenticated requests made from web browsers. Higher limits will be applied to identified traffic in April. Bots running in Toolforge/WMCS or with the bot user right on any wiki should not be affected for now. However, all developers are advised to follow updated best practices. For more information, see [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits|Wikimedia APIs/Rate limits]]. * The new GraphQL API has been released. The API was developed as a flexible alternative to select features of the Wikidata Query Service (WDQS), to improve developer experience and foster adaptability, and efficient data access. Try it out and [[d:Wikidata:Wikibase GraphQL#Feedback and development|give feedback]]. You can also [https://greatquestion.co/wikimediadeutschland/GraphQLAPI/apply sign up for usability tests]. * The [[m:Special:MyLanguage/Product and Technology Advisory Council/Unsupported Tools Working Group|PTAC Unsupported Tools Working Group]] continued improvements to [[commons:Special:MyLanguage/Commons:Video2commons#|Video2Commons]] in February, with fixes addressing authentication errors, large-file handling, task queue visibility, and clearer upload behavior. Work is still ongoing in some areas, including changes related to deprecated server-side uploads. Read [[m:Special:MyLanguage/Product and Technology Advisory Council/Unsupported Tools Working Group#February 2026|this update]] to learn more. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.19|MediaWiki]] '''In depth''' * The Article Guidance team invites experienced Wikipedia editors from selected [[mw:Special:MyLanguage/Article guidance/Pilot wikis and collaborators#Collaborators|pilot wikis]] and interested contributors from other Wikipedias to fill out this questionnaire which is available in [https://docs.google.com/forms/d/e/1FAIpQLSfmLeVWnxmsCbPoI_UF2jyRcn73WRGWCVPHzerXb4Cz97X_Ag/viewform English], [https://docs.google.com/forms/d/e/1FAIpQLSd6rzr4XXQw8r4024fE3geTPFe13M_6w7Mitj-YJi0sOlWTAw/viewform?usp=header Arabic], [https://docs.google.com/forms/d/e/1FAIpQLSdok3-RfB18lcugYTUMGkpwmqG_8p760Wv4dCXitOXOszjUDw/viewform?usp=header Bengali], [https://docs.google.com/forms/d/e/1FAIpQLSfjTfYp4jEo0akA4B1e-Nfg3QZPCudUjhJzHzzDi6AHyAaMGA/viewform?usp=header Japanese], [https://docs.google.com/forms/d/e/1FAIpQLScteVoI29Aue4xc72dekk-6RYtvmMgQxzMI900UOawrFrSTWg/viewform?usp=header Portuguese], [https://docs.google.com/forms/d/e/1FAIpQLSetdxnYwL3ub2vqA7awCg5hJZPMIYcDPaiTe12rY9h0GYnVlw/viewform?usp=header Persian], and [https://docs.google.com/forms/d/e/1FAIpQLScNvfJF-Ot-4pzA4qAN771_0QDJ4Li19YcUsaTgSKW8Nc7U_Q/viewform?usp=header Turkish]. Your answers will help the team customize guidance for less experienced editors and help them learn community policies and practices while creating an article. Learn more [[mw:Special:MyLanguage/Article guidance|on the project page]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/11|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W11"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:53, 9 March 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30213008 --> == Tech News: 2026-12 == <section begin="technews-2026-W12"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/12|Translations]] are available. '''Updates for editors''' * The [[mw:Special:MyLanguage/Help:Extension:CodeMirror|{{int:codemirror-beta-feature-title}}]] beta feature, also known as [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror 6]], has been used for wikitext syntax highlighting since November 2024. It will be promoted out of beta by May 2026 in order to bring improvements and new [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Features|features]] to all editors who use the standard syntax highlighter. If you have any questions or concerns about promoting the feature out of beta, [[mw:Special:MyLanguage/Help talk:Extension:CodeMirror|please share]]. [https://phabricator.wikimedia.org/T259059] * Some changes to local user groups are performed by stewards on Meta-Wiki and logged there only. Now, interwiki rights changes will be logged both on Meta-Wiki and the wiki of the target user to make it easier to access a full record of user's rights changes on a local wiki. Past log entries for such changes will be backfilled in the coming weeks. [https://phabricator.wikimedia.org/T6055] * On wikis using [[m:Special:MyLanguage/Flagged Revisions|Flagged Revisions]], the number of pending changes shown on [[{{#Special:PendingChanges}}]] previously counted pages which were no longer pending review, because they have been removed from the system without being reviewed, e.g. due to being deleted, moved to a different namespace, or due to wiki configuration changes. The count will be correct now. On some wikis the number shown will be much smaller than before. There should be no change to the list of pages itself. [https://phabricator.wikimedia.org/T413016] * Wikifunctions composition language has been rewritten, resulting in a new version of the language. This change aims to increase service stability by reducing the orchestrator's memory consumption. This rewrite also enables substantial latency reduction, code simplification, and better abstractions, which will open the door to later feature additions. Read more about [[f:Special:MyLanguage/Wikifunctions:Status updates/2026-03-11|the changes]]. * Users can now sort search results alphabetically by page title. The update gives an additional option to finding pages more easily and quickly. Previously, results could be sorted by Edit date, Creation date, or Relevance. To use the new option, open 'Advanced Search' on the search results page and select 'Alphabetically' under 'Sorting Order'. [https://phabricator.wikimedia.org/T403775] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the bug that prevented UploadWizard on Wikimedia Commons from importing files from Flickr has now been fixed. [https://phabricator.wikimedia.org/T419263] '''Updates for technical contributors''' * A new special page, [[{{#special:LintTemplateErrors}}]], has been created to list transcluded pages that are flagged as containing lint errors to help users discover them easily. The list is sorted by the number of transclusions with errors. For example: [[{{#special:LintTemplateErrors}}/night-mode-unaware-background-color]]. [https://phabricator.wikimedia.org/T170874] * Users of the [[mw:Special:MyLanguage/Help:Extension:CodeMirror|{{int:codemirror-beta-feature-title}}]] beta feature have been using [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror]] instead of [[mw:Special:MyLanguage/Extension:CodeEditor|CodeEditor]] for syntax highlighting when editing JavaScript, CSS, JSON, Vue and Lua content pages, for some time now. Along with promoting CodeMirror 6 out of beta, the plan is to replace CodeEditor as the standard editor for these content models by May 2026. [[mw:Special:MyLanguage/Help talk:Extension:CodeMirror|Feedback or concerns are welcome]]. [https://phabricator.wikimedia.org/T419332] * The [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror]] JavaScript modules will soon be upgraded to CodeMirror 6. Leading up to the upgrade, loading the <code dir=ltr>ext.CodeMirror</code> or <code dir=ltr>ext.CodeMirror.lib</code> modules from gadgets and user scripts was deprecated in July 2025. The use of the <code dir=ltr>ext.CodeMirror.switch</code> hook was also deprecated in March 2025. Contributors can now make their scripts or gadgets compatible with CodeMirror 6. See the [[mw:Special:MyLanguage/Extension:CodeMirror#Gadgets and user scripts|migration guide]] for more information. [https://phabricator.wikimedia.org/T373720] * The MediaWiki Interfaces team is expanding coverage of REST API module definitions to include [[mw:Special:MyLanguage/API:REST API/Extensions|extension APIs]]. REST API modules are groups of related endpoints that can be independently managed and versioned. Modules now exist for [https://phabricator.wikimedia.org/T414470 GrowthExperiments] and [https://phabricator.wikimedia.org/T419053 Wikifunctions] APIs. As we migrate extension APIs to this structure, documentation will move out of the main MediaWiki OpenAPI spec and REST Sandbox view, and will instead be accessible via module-specific options in the dropdown on the [https://test.wikipedia.org/wiki/Special:RestSandbox REST Sandbox] (i.e., [[{{#Special:RestSandbox}}]], available on all wiki projects). * The [[mw:Special:MyLanguage/Extension:Scribunto|Scribunto]] extension provides different pieces of information about the wiki where the module is being used via the [[mw:Special:MyLanguage/Extension:Scribunto/Lua reference manual|mw.site]] library. Starting last week, the library also provides a [[mw:Special:MyLanguage/Extension:Scribunto/Lua reference manual#mw.site.wikiId|way]] of accessing the [[mw:Special:MyLanguage/Manual:Wiki ID|wiki ID]] that can be used to facilitate cross-wiki module maintenance. [https://phabricator.wikimedia.org/T146616] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.20|MediaWiki]] '''In depth''' * The [[m:Special:MyLanguage/Coolest Tool Award|2026 Coolest Tool Award]] celebrating outstanding community tools, is now open for nominations! Nominate your favorite tool using the [https://wikimediafoundation.limesurvey.net/435684?lang=en nomination survey] form by 23 March 2026. For more information on privacy and data handling, please see the [[foundation:Special:MyLanguage/Legal:Coolest_Tool_Award_2026_Survey_Privacy_Statement|survey privacy statement]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/12|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W12"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:35, 16 March 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30260505 --> == Tech News: 2026-13 == <section begin="technews-2026-W13"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/13|Translations]] are available. '''Weekly highlight''' * Wikimedia site users can now log in without a password using passkeys. This is a secure method supported by fingerprint, facial recognition, or PIN. With this change, all users who opt for passwordless login will find it easier, faster, and more secure to log in to their accounts using any device. The new passkey login option currently appears as an autofill suggestion in the username field. An additional [[phab:T417120|"Log in with passkey" button]] will soon be available for users who have already registered a passkey. This update will improve security and user experience. The [[c:File:Passwordless_login_screencast.webm|screen recording]] demonstrates the passwordless login process step by step. * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on Wednesday, 25 March 2026 at [https://zonestamp.toolforge.org/1774450800 15:00 UTC]. This is for the datacenter server switchover backup tests, [[wikitech:Deployments/Yearly calendar|which happen twice a year]]. During the switchover, all Wikimedia website traffic is shifted from one primary data center to the backup data center to test availability and prevent service disruption even in emergencies. '''Updates for editors''' * Wikimedia site users can now export their notifications older than 5 years using a [[toolforge:echo-chamber|new Toolforge tool]]. This will ensure that users retain their important notifications and avoid them being lost based on the planned change to delete notifications older than 5 years, as previously announced. [https://phabricator.wikimedia.org/T383948] * Wikipedia editors in Indonesian, Thai, Turkish, and Simple English now have access to Special:PersonalDashboard. This is an [[mw:Special:MyLanguage/Moderator Tools/Dashboard|early version of an experience]] that introduces newer editors to patrolling workflows, making it easier for them to move from making edits to participating in more advanced moderation work on their project. [https://phabricator.wikimedia.org/T402647] * The [[Special:Block]] now has two minor interface changes. Administrators can now easily perform indefinite blocks through a dedicated radio button in the expiry section. Also, choosing an indefinite expiry provides a different set of common reasons to select from, which can be changed at: [[MediaWiki:Ipbreason-indef-dropdown]]. [https://phabricator.wikimedia.org/T401823] * Mobile editors [[mw:Special:MyLanguage/Contributors/Account Creation Experiments#Logged-out|at several wikis]] can now see an improved logged-out edit warning, thanks to the recent updates from the Growth team. These changes released last week are part of ongoing efforts and tests to enhance [[mw:Special:MyLanguage/Contributors/Account Creation Experiments|account creation experience on mobile]] and then increase participation. [https://phabricator.wikimedia.org/T408484] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:36}} community-submitted {{PLURAL:36|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the bug that prevented mobile web users from seeing the block information when affected by multiple blocks has been fixed. They can now see messages of all the blocks currently affecting them when they access Wikipedia. '''Updates for technical contributors''' * Images built using Toolforge will soon get the upgraded buildpacks version, bringing support for newer language versions and other upstream improvements and fixes. If you use Toolforge Build Service, review the recent [https://lists.wikimedia.org/hyperkitty/list/cloud-announce@lists.wikimedia.org/thread/EMYTA32EV2V5SQ2JIEOD2CL66YFIZEKV/ cloud-announce email] and update your build configuration as necessary to ensure your tools are compatible. [https://wikitech.wikimedia.org/w/index.php?title=Help:Toolforge/Building_container_images&oldid=2392097#Buildpack_environment_upgrade_process][https://phabricator.wikimedia.org/T380127] * The [https://api.wikimedia.org/wiki/Main_Page API Portal] documentation wiki will shut down in June 2026. API keys created on the API Portal will continue to work normally. api.wikimedia.org endpoints will be deprecated gradually starting in July 2026. Documentation on the API Portal is moving to [[mw:Wikimedia APIs|mediawiki.org]]. Learn more on the [[wikitech:API Portal/Deprecation|project page]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.21|MediaWiki]] '''In depth''' * [[m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]] is considering improvements to [[m:WMDE Technical Wishes/References/VisualEditor automatic reference names|automatically generated reference names in VisualEditor]]. Please check out the [[m:WMDE Technical Wishes/References/VisualEditor automatic reference names#Proposed solutions|proposed solutions]] and participate in the [[m:Talk:WMDE Technical Wishes/References/VisualEditor automatic reference names#Request for comment|request for comment]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/13|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W13"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:51, 23 March 2026 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30268305 --> == Tech News: 2026-14 == <section begin="technews-2026-W14"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/14|Translations]] are available. '''Weekly highlight''' * The Beta version of [[abstract:|Abstract Wikipedia]] a new Wikimedia project which is language-independent, was launched last week. The project allows communities to build Wikipedia articles in their native language, which can be readily accessed by other users in their own languages. The wiki is powered by instructions from Wikifunctions and also based on structured content from Wikidata. [[:f:Special:MyLanguage/Wikifunctions:Status updates/2026-03-26|Read more]]. '''Updates for editors''' * The Growth team is running an A/B test to evaluate a clearer, more user-friendly message that promotes account creation on wikis. Currently when logged-out mobile users begin editing, they see a jarring warning message that can feel abrupt and discouraging. This also presents temporary account editing as the default rather than encouraging account creation. The test is running on ten Wikipedias, including Arabic, French, Spanish and German. [[mw:Special:MyLanguage/Contributors/Account Creation Experiments#2. Improve logged-out warning message (T415160)|Read more]]. * The Wikimedia Apps team is inviting feedback on [[mw:Special:MyLanguage/Wikimedia Apps/Team/Future of Editing on the Mobile Apps|how editing should work on the Wikipedia mobile apps]]. The discussion focuses on improving how users access editing tools when they tap "Edit". This is part of a broader effort to convert readers who develop an interest in editing, to access a more user-friendly pathway to start contributing. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:45}} community-submitted {{PLURAL:45|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where citation fetching from the large newspaper archive [https://www.newspapers.com Newspapers.com] was no longer working, due to a block in [[mw:Special:MyLanguage/Citoid|Citoid]] requests, has now been fixed. [https://phabricator.wikimedia.org/T419903] '''Updates for technical contributors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.22|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/14|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W14"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:25, 30 March 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30329462 --> == Tech News: 2026-15 == <section begin="technews-2026-W15"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/15|Translations]] are available. '''Updates for editors''' * The [[mw:Special:MyLanguage/Help:Extension:CampaignEvents|CampaignEvents extension]] now includes a new group goal-setting feature, enabling organizers to set and track event goals such as the number of articles created and participating contributors in real time. Similarly, participants can work toward shared targets and see their collective impact as the event unfolds. The feature is now available on all Wikimedia wikis. Learn more in [[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Registration/Collaborative contributions#Goal setting|the documentation]]. * [[File:Maki-gift-15.svg|12px|link=|class=skin-invert|Wishlist item]] The new [[mw:Special:MyLanguage/Help:Watchlist labels|watchlist labels]] feature (announced in [[m:Special:MyLanguage/Tech/News/2026/07|Tech News 2026-07]]) is now available via VisualEditor, the source editor, and the 'watchstar' (or watch link, for skins that don't have a star icon). Previously it was only possible to assign labels via [[Special:EditWatchlist|EditWatchlist]]. In all three places it is a new field following the expiry field. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where talk pages on mobile with Parsoid are unusable after empty section headers, has now been fixed. [https://phabricator.wikimedia.org/T419171] '''Updates for technical contributors''' * The [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|sub-referencing feature]], which lets editors add details to an existing reference without duplicating it, will be gradually rolled out to [[phab:T414094|more wikis]] later this year. Wikis using the [[mw:Special:MyLanguage/Reference Tooltips|Reference Tooltips]] gadget are encouraged to update their version (typically at [[m:MediaWiki:Gadget-ReferenceTooltips.js|MediaWiki:Gadget-ReferenceTooltips.js]] as shown [https://en.wikipedia.org/w/index.php?diff=1344408362 here]) to ensure compatibility. Other reference-related gadgets may also be affected. [https://phabricator.wikimedia.org/T416304] * All Wikinews editions will be closed and switched to read-only mode on 4 May 2026. Content will remain accessible, but no new edits or articles can be added. This closure was approved by the Board of Trustees of the Wikimedia Foundation following extended discussions. [[m:Wikimedia Foundation Board noticeboard#Board of Trustees Approves Closure of Wikinews|Read more]]. * The [[:mw:Special:MyLanguage/API:Action API|Action API]] has had several formats for requested output. One of them, <bdi lang="zxx" dir="ltr"><code><nowiki>format=php</nowiki></code></bdi>, is being removed soon. Please ensure your scripts or bots use the [[mw:Special:MyLanguage/API:Data formats#Output|JSON format]]. This removal should affect very few scripts and bots. [https://phabricator.wikimedia.org/T118538] * The [[Special:NamespaceInfo|Special:NamespaceInfo]] page now includes namespace aliases. For example "WP" for the "Project" ("Wikipedia") namespace on the German Wikipedia. [https://phabricator.wikimedia.org/T381455] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.23|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/15|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W15"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:19, 6 April 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30362761 --> == Tech News: 2026-16 == <section begin="technews-2026-W16"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/16|Translations]] are available. '''Weekly highlight''' * Experienced editors are invited to [https://b24e11a4f1.catalyst.wmcloud.org/wiki/Main_Page test] the [[mw:Special:MyLanguage/Article guidance|Article guidance]] feature, designed to help less-experienced editors create well-structured, policy-compliant Wikipedia articles. Testing instructions are [[mw:Special:MyLanguage/Article guidance/Test feature guide|available]]. Also, after reviewing [https://b24e11a4f1.catalyst.wmcloud.org/wiki/Category:Pages_using_article_guidance the outlines], please provide feedback on the [[mw:Talk:Article guidance|project talk page]]. Based on your input, the feature will be refined and transferred to the pilot Wikipedias to translate and adapt. Check out [[c:File:Article Guidance workflow demo - April 2026.webm|the video]] explaining the feature. '''Updates for editors''' * On most wikis, all autoconfirmed users can now use [[Special:ChangeContentModel|Special:ChangeContentModel]] page to [[mw:Special:MyLanguage/Help:ChangeContentModel|create new pages with custom content models]], such as mass message lists, making custom page formats more accessible. Check [[Special:ListGroupRights|Special:ListGroupRights]] for the status of your wiki. [https://phabricator.wikimedia.org/T248294] * The Growth team has launched an [[mw:Special:MyLanguage/Contributors/Account_Creation_Experiments|account creation experiment]] to evaluate whether adding an account creation button to the mobile web header increases new account registrations and encourages more mobile users to contribute to the wikis. The experiment is currently live on Hindi, Indonesian, Bengali, Thai, and Hebrew Wikipedia, and targets 10% of logged-out mobile web users. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where VisualEditor could get stuck loading on Windows devices with animations turned off, has now been fixed. [https://phabricator.wikimedia.org/T382856] '''Updates for technical contributors''' * Starting later this week, {{int:group-abusefilter}} who have the [[mw:Special:MyLanguage/Help:Extension:CodeMirror|{{int:codemirror-beta-feature-title}}]] beta feature enabled will have [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror]] instead of [[mw:Special:MyLanguage/Extension:CodeEditor|CodeEditor]] as the editor at [[Special:AbuseFilter|Special:AbuseFilter]]. This is part of the broader effort to make the user experience more consistent across all editors. [https://phabricator.wikimedia.org/T399673][https://phabricator.wikimedia.org/T419332] * Tools and bots that access the [[mw:Special:MyLanguage/Notifications/API|Notifications API]] (<bdi lang="zxx" dir="ltr"><code><nowiki>action=query&meta=notifications</nowiki></code></bdi>) will need to update their OAuth or BotPassword grants to also include access to private notifications. [https://phabricator.wikimedia.org/T421991] * Due to a library upgrade, listings on category pages may be displayed out of order starting on Monday, 20th April. A migration script will be run to correct this, and will take hours to days depending on the size of the wiki (up to a week for English Wikipedia). [https://phabricator.wikimedia.org/T422544] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.24|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/16|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W16"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 15:19, 13 April 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30380527 --> == Tech News: 2026-17 == <section begin="technews-2026-W17"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/17|Translations]] are available. '''Weekly highlight''' * After two years of development, [[mw:Special:MyLanguage/Help:Extension:CodeMirror|{{int:codemirror-beta-feature-title}}]], also known as [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror 6]], is to be promoted out of beta on Tuesday, April 21. It brings better code and wikitext readability, reduction in typing errors, and other [[mw:Special:MyLanguage/Help:Extension:CodeMirror|benefits]] to all users of the standard syntax highlighter. A huge thank you to volunteer [https://phabricator.wikimedia.org/p/Bhsd/ Bhsd] who developed many of the new features, including [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Code folding|code folding]], [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Autocompletion|autocompletion]], and [[mw:Special:MyLanguage/Help:Extension:CodeMirror#Linting|linting]]. [https://phabricator.wikimedia.org/T259059] * A major update to the Wikipedia app for iOS is now rolling out, redesigning the interface to align with Apple's latest "Liquid Glass" visual design. [https://apps.apple.com/us/app/wikipedia/id324715238 Download the latest version] and explore the update. '''Updates for editors''' * [[mw:Special:MyLanguage/Readers/Reader Experience/WE3.3.4 Reading lists|Reading lists]] is a feature which allows readers to save articles to a list for reading later. This feature is now in beta on Arabic, French, Indonesian, Vietnamese, and Chinese Wikipedias and by default for all new accounts on all Wikipedias. * An experiment which explores extending [[mw:Special:MyLanguage/Readers/Reader Growth/Mobile page previews|Page Previews to mobile web]] will be launched in the week of April 20 on Arabic, English, French, Italian, Polish, and Vietnamese Wikipedias. Page Previews are pop-ups that display a thumbnail, lead paragraph, and a link to open the full article of a blue link, thereby improving content discovery. The feature is already available on desktop and in the apps. [[m:Special:MyLanguage/List of experiments in Product and Technology#Template|Read more about this experiment and others]]. * On several wikis, logged-in editors who haven't [[mw:Special:MyLanguage/Help:Email confirmation|confirmed their email addresses]] can now see a banner encouraging them to do so. Having the email address confirmed allows a user to restore access to the account if they lose it. [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security#Encouraging users to confirm their email addresses|Learn more]]. [https://phabricator.wikimedia.org/T421366] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:15}} community-submitted {{PLURAL:15|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where editing very large wiki pages in the 2017 wikitext editor caused slow loading, preview and scrolling lag, and performance issues when selecting, cutting, or pasting content, has now been fixed. [https://phabricator.wikimedia.org/T184857] '''Updates for technical contributors''' * As part of the promotion of [[mw:Special:MyLanguage/Help:Extension:CodeMirror|CodeMirror]] from a beta feature, all users will use [[mw:Special:MyLanguage/Extension:CodeMirror|CodeMirror]] instead of [[mw:Special:MyLanguage/Extension:CodeEditor|CodeEditor]] for syntax highlighting when editing JavaScript, CSS, JSON, Vue and Lua content pages. [https://phabricator.wikimedia.org/T419332] * The <code>mirrors.wikimedia.org</code> service for Debian and Ubuntu users will sunset and stop working on May 15. The resources for the service will be replaced with new and better options. Some users may need to switch to a different server which should take about a minute. [https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/LJYRIS4WB66HIRCAO4GIDTXCMDVZRBMA/ You can read more]. [https://phabricator.wikimedia.org/T416707] * The <bdi lang="zxx" dir="ltr"><code><nowiki>image</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>oldimage</nowiki></code></bdi> table will be removed from [[wikitech:Help:Wiki Replicas|wikireplicas]]. If your tools or queries access <bdi lang="zxx" dir="ltr"><code><nowiki>image</nowiki></code></bdi> or <bdi lang="zxx" dir="ltr"><code><nowiki>oldimage</nowiki></code></bdi> directly, please update them to use the <bdi lang="zxx" dir="ltr"><code><nowiki>file</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>filerevision</nowiki></code></bdi> table before 28 May. [https://phabricator.wikimedia.org/T28741] * Following the recent implementation of global API rate limits on unidentified traffic, the Wikimedia Foundation will continue efforts to ensure [[mw:Special:MyLanguage/MediaWiki Product Insights/Responsible Reuse|fair use of infrastructure]] by applying global limits to identified API traffic beginning the last week of April. These limits are intentionally set as high as possible to minimise impact on the community. Bots running in Toolforge/WMCS or with the bot user right on any wiki should not be affected for now. However, all developers are advised to follow updated best practices. For more information, see [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits|Wikimedia APIs/Rate limits]] and [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits/FAQ|Frequently Asked Questions]]. * The [[mw:Special:MyLanguage/Attribution API|Attribution API]] is now available as a [[mw:Special:MyLanguage/Wikimedia APIs/Stability policy|beta]]. The API fetches information for crediting Wikimedia articles and media files wherever they are used. Reference documentation is available through the REST Sandbox special page available on all Wikimedia wikis (such as the [https://en.wikipedia.org/w/index.php?api=attribution.v0-beta&title=Special%3ARestSandbox REST sandbox on English Wikipedia]). Share your feedback on the [[mw:Talk:Attribution API|project talk page]]. * There is no new MediaWiki version this week. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/17|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W17"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 15:00, 20 April 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30432763 --> == Tech News: 2026-18 == <section begin="technews-2026-W18"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/18|Translations]] are available. '''Updates for editors''' * There is a change in how new users are autoconfirmed that will improve anti-vandalism protection. Currently, users who have had an account for a few days and made a few edits are automatically added to the [[{{int:grouppage-autoconfirmed/{{CONTENTLANGUAGE}}}}|{{int:group-autoconfirmed}}]] group. This configuration tends to be exploited by some vandals, who create accounts and start to use them only after some time. To mitigate this, the configuration will be updated next week so that – for the purpose of becoming autoconfirmed – the account age will be counted from their first edit, instead of registration date. The numeric value of the age threshold will remain the same. This change will be deployed only to wikis which require at least one edit as part of the autoconfirmation conditions. [https://phabricator.wikimedia.org/T418484] * All Wikipedia users with new accounts and those who activated the "automatically enable most beta features" option in their preference can now use the [[mw:Special:MyLanguage/Readers/Reader Experience/WE3.3.4 Reading lists|reading lists]] beta feature to save articles for later reading. This helps organize reading interests in one place for convenient access. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where infobox images have huge padding in Firefox, has been fixed. [https://phabricator.wikimedia.org/T423676] '''Updates for technical contributors''' * As a reminder, the global API rate limits will be applied this week to identified API traffic. This is to help ensure [[mw:MediaWiki Product Insights/Responsible Reuse|fair use of infrastructure]]. Bots running in Toolforge/WMCS or with the bot user right on any wiki should not be affected for now. However, all developers are advised to follow updated best practices. For more information, including the actual rate limits, see [[mw:Wikimedia APIs/Rate limits|Wikimedia APIs/Rate limits]] and [[mw:Wikimedia APIs/Rate limits/FAQ|Frequently Asked Questions]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.26|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/18|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W18"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:06, 27 April 2026 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30458046 --> == Tech News: 2026-19 == <section begin="technews-2026-W19"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/19|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Article guidance|Article guidance]] team invites experienced editors of [[mw:Special:MyLanguage/Article guidance/Pilot wikis and collaborators|pilot Wikipedias]]—Arabic, Bangla, Japanese, Portuguese, Persian, Turkish, Simple English, Spanish, and French—to help translate and adapt [https://b24e11a4f1.catalyst.wmcloud.org/wiki/Category:Pages_using_article_guidance sample outlines]. These outlines will guide editors in creating clear, well-structured, and policy-compliant articles when using [https://b24e11a4f1.catalyst.wmcloud.org/wiki/Special:NewArticle the feature] once it is launched in May 2026. [[mw:Special:MyLanguage/Article guidance#Adapting a sample outline in a Wikipedia|Simple instructions]] on how to translate and adapt the outlines are available. '''Updates for editors''' * The [[:m:Special:MyLanguage/Product and Technology Advisory Council|Product and Technology Advisory Council]] has published [[:m:Special:MyLanguage/Product and Technology Advisory Council/May 2026 draft PTAC recommendation for feedback|draft recommendations]] on a model that affiliates can follow when contributing to the technical space. Community members are invited to provide feedback on the recommendation until May 8th [[:m:Talk:Product and Technology Advisory Council/May 2026 draft PTAC recommendation for feedback|on the talk page]]. * The number of available thumbnail size preferences in MediaWiki is being reduced to three standardized options—Small (180px), Regular (250px), and Large (400px), as part of ongoing efforts to improve performance and reduce strain on thumbnail services. As a result, existing preferences will be mapped to the nearest new size (for example, smaller selections like 120px or 150px will render at 180px, while larger ones like 300px or 360px will render at 400px). The preferences interface will soon be updated to reflect these changes, and users who wish to opt out or provide feedback can do so. [https://phabricator.wikimedia.org/T424909] * From now on, even when a permission expires automatically, users will receive an Echo notification similar to the standard notification for permission changes. There is a difference between this and [[m:Special:MyLanguage/Global reminder bot|Global reminder bot]] in that the latter reminds users a week ''before'' the rights are due to expire, so that they can renew the rights. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:32}} community-submitted {{PLURAL:32|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the problem where the ULS language selector in [[m:Special:Translate|Special:Translate]] would scroll vertically when it shouldn't, has been resolved. Previously, when users opened the "Translate to English" dropdown and typed certain inputs, the dialog would scroll vertically by a few pixels even when there was enough space to display all results. The dropdown no longer shifts unnecessarily when filtering languages. [https://phabricator.wikimedia.org/T358864] * The [[m:Special:GlobalWatchlist|Global Watchlist]], which lets you view your watchlists from multiple wikis on a single page, continues to improve. For example, watchlists for Wikibase sites such as [[:d:|Wikidata]] now support [[mw:Special:MyLanguage/Extension:EntitySchema|EntitySchema]] elements for better tracking. The Live Updates mode now refreshes the special page every 60 seconds to comply with the updated [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits|global API rate limits]] for improved real-time responsiveness. Additionally, a directionality bug that displayed links as "changes 3" instead of "3 changes" in mixed-direction lists has been fixed. [https://phabricator.wikimedia.org/T415450][https://phabricator.wikimedia.org/T424422][https://phabricator.wikimedia.org/T418091] '''Updates for technical contributors''' * The second phase of [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits|global API rate limits]] has been rolled out to reduce the [[diffblog:2026/03/26/quo-vadis-crawlers-progress-and-whats-next-on-safeguarding-our-infrastructure/|impact of AI crawlers]] and ensure fair, sustainable access to Wikimedia resources, prioritising human and mission-aligned traffic. [[mw:Special:MyLanguage/Wikimedia APIs/Rate limits#Limits|Limits]] have been shifted from per-hour to per-minute, producing smoother traffic patterns and more predictable API load. Community users are not expected to be affected, and no action is required. Early indications show some User-Agent-based requestors are adjusting behaviour, and around 64% of automated API traffic has been identified. Monitoring continues, and Wikimedia Enterprise remains available for commercial support. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.46/wmf.27|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/19|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W19"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:43, 4 May 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30498077 --> == Tech News: 2026-20 == <section begin="technews-2026-W20"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/20|Translations]] are available. '''Weekly highlight''' * Community Tech has published [[m:Special:MyLanguage/Community Wishlist/How to write a good wish|new guidance]] explaining how wishes on Community Wishlist are triaged and prioritized. The documentation is intended to help contributors write stronger proposals by clarifying the factors that influence prioritization decisions. Beyond vote counts, the guidance highlights considerations such as potential impact on the community when determining which wishes move forward. '''Updates for editors''' * The Reader Growth team is launching an experiment to test a new [[mw:Special:MyLanguage/Readers/Reader_Growth/Share_Card|Share Card feature]] that allows readers to create visually engaging cards from Wikipedia articles or selected article sections and share them online, with each card linking back to the original article to help expand readership and article discovery. The mobile-only A/B test will be available to a portion of readers on Arabic, Chinese, French, Vietnamese, and English Wikipedia to better understand reading and sharing habits, and is scheduled to begin the week of May 18 and run for four weeks. * The Android and iOS Wikipedia apps recently released the [[mw:Special:MyLanguage/Wikimedia_Apps/Team/25th_Birthday_Reading_Challenge|25-day reading challenge]] into Beta, as part of efforts to drive reader engagement by encouraging users to complete reading milestones. To track their reading streak during the challenge, App users can add a widget featuring Baby Globe to their home screen. The challenge officially begins May 11. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:17}} community-submitted {{PLURAL:17|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the global preference for enabling syntax highlighting in wikitext could unexpectedly disable itself after being turned on, has now been fixed. [https://phabricator.wikimedia.org/T425286] '''Updates for technical contributors''' * [[File:Octicons-tools.svg|12px|link=|alt=|Advanced item]] The ResourceLoader module <bdi lang="zxx" dir="ltr"><code><nowiki>mediawiki.ui.input</nowiki></code></bdi>, deprecated since [[m:Special:MyLanguage/Tech/News/2023/39|September 2023]], will be removed this week. There is a [[mw:Special:MyLanguage/Codex/Migrating_from_MediaWiki_UI|guide for migrating from MediaWiki UI to Codex]] for any tools that use it. [https://phabricator.wikimedia.org/T420125] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.2|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/20|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W20"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:20, 11 May 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30524429 --> == Tech News: 2026-21 == <section begin="technews-2026-W21"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/21|Translations]] are available. '''Weekly highlight''' * The Abstract Wikipedia team has identified five potential pilot wikis to assess their interest in adopting abstract articles on their wikis. The pilots are Malayalam, Bengali, Dagbani, Arabic, and Indonesian Wikipedia. The feedback period will be open until May 22. If your community is interested in becoming a pilot, [[m:Talk:Abstract Wikipedia|let us know on Meta]]. '''Updates for editors''' * An experiment to show [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]] to logged-out readers on mobile web will launch on May 18 across German, Spanish, Italian, Portuguese, Polish, Dutch, Turkish, and Urdu Wikipedias, and will run for one month. The effort supports broader goals of helping readers save and organize articles for later reading, while encouraging habits that could lead to future Wikipedia contributions. * To support a bookmark button in the Reading List beta feature, the "Tools > Action" menu has been updated to display icons, including the watch star indicator that helps editors identify temporarily watched articles. The icons now also match those used on mobile, improving consistency across platforms. The change is currently limited to the actions menu and mainly affects editors with privileged user rights. [https://phabricator.wikimedia.org/T426008] * [[mw:Special:MyLanguage/VisualEditor/Suggestion Mode|Suggestion Mode]] was released as an [[w:en:A/B test|A/B test]] for newcomer editors on the mobile website at [[phab:T421189|~15 Wikipedias]]. The experiment will measure the impact that Suggestion Mode has on the proportion of newcomer mobile web edit sessions that result in constructive (un-reverted) article edits. The experiment will also evaluate the feature's impact on editor retention, and monitor changes in revert and block rates. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:27}} community-submitted {{PLURAL:27|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue in the Wikipedia Android app where images could sometimes fail to load after opening a recommended reading list notification, has now been fixed. [https://phabricator.wikimedia.org/T418231] '''Updates for technical contributors''' * The [[mw:Special:MyLanguage/Wikidata Platform|Wikidata Platform team]] has published its [[d:Special:MyLanguage/Wikidata:SPARQL query service/WDQS backend update/Backend Replacement|backend replacement recommendation]] and accompanying [[wikitech:Wikidata Query Service/WDQS Architecture re-design|technical architecture]] for the migration of the Wikidata Query Service (WDQS) away from Blazegraph. Feedback is invited until May 25th 2026, especially on potential gaps and impacts on advanced use cases. Wikidata community members and WDQS users are also encouraged to help identify high-impact tools and workflows that may need attention on [[d:Wikidata:SPARQL query service/WDQS backend update/High-Impact Use Cases|this page]]. Feedback can be shared on the [[d:Wikidata talk:SPARQL query service/WDQS backend update|Migration talk page]] or during the [[d:Special:MyLanguage/Wikidata:Blazegraph Migration Office Hours|next office hour]]. See the [[d:Special:MyLanguage/Wikidata:Wikidata Platform team/Newsletter|WDP team newsletter]] for more details. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.3|MediaWiki]] '''In depth''' * On English, French, Japanese, and a few other Wikipedias, there was a [[diffblog:2025/09/02/better-detecting-bots-and-replacing-our-captcha/|trial of hCaptcha]], a third-party bot detection service. The trial showed that hCaptcha effectively detects and deters some bad-faith automated activity, on its own and by giving [[w:en:Wikipedia:Village pump (technical)/Archive 225#Introducing SuggestedInvestigations|checkusers and stewards]] signals to look into. Because the results were positive, hCaptcha will be rolled out across all wikis over the next few weeks. [[mw:Special:MyLanguage/Product Safety and Integrity/Anti-abuse signals/hCaptcha|See the hCaptcha project page]] for technical information about the implementation and privacy protections. [[diffblog:2026/05/04/better-detecting-bots-and-replacing-our-captcha-part-2/|Learn more]]. * The latest Community Tech update is now available, with progress across several Community Wishlist initiatives, including Reading Lists expansion from the mobile app to the website, new language support for "Who Wrote That" and the Personal Dashboard, improvements to 3D rendering and Charts, and upcoming work on talk page sorting, audio playback, and editing workflows. The update also shares current priorities, wishlist status trends, and opportunities for community feedback on future focus areas and the Wikimedia Foundation’s 2026–2027 Annual Plan. [[m:Special:MyLanguage/Community Wishlist/Updates#May 13, 2026: Latest updates from the Community Tech team|Read the full newsletter for details]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/21|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W21"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:21, 18 May 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30539262 --> == Tech News: 2026-22 == <section begin="technews-2026-W22"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/22|Translations]] are available. '''Weekly highlight''' * Following a [[mw:Special:MyLanguage/Contributors/Account Creation Experiments#LOWM|successful account creation experiment]], an improved logged-out edit warning message will be deployed to all Wikimedia wikis in the first week of June. The change will only affect logged-out users on mobile web who open an editing session. The updated experience is designed to encourage account creation more clearly, while still allowing users to edit with temporary accounts. Results from the experiment showed a significant increase in account creation, with a 27% relative lift among users shown the updated message. As expected, as more people funnel into account creation, temporary accounts decreased by a relative 16%. The experiment did not show any significant changes in constructive edit rates or other monitored contributor metrics. [https://phabricator.wikimedia.org/T424595] '''Updates for editors''' * For security reasons, members of certain user groups are [[m:Special:MyLanguage/Mandatory two-factor authentication for users with some extended rights|required to have two-factor authentication]] (2FA) enabled. Members of these groups will be unable to disable the last 2FA method on their account, and it will be impossible to add users without 2FA to these groups. Users will still be able to add new authentication methods or remove them, as long as at least one method is continuously enabled. In the next few weeks, users without 2FA will be removed from these groups. Notably, this applies to bureaucrats. See the linked tasks for deployment schedules. [https://phabricator.wikimedia.org/T423119][https://phabricator.wikimedia.org/T423120] * [[m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]] will run an [[w:en:A/B testing|A/B test]] on [[:phab:T415904|10 wikis]], testing [[m:WMDE Technical Wishes/References/Reference Previews|potential improvements for Reference Previews]]. The experiment will run for ~2 weeks at the end of May / beginning of June and will affect 10% of desktop readers on the participating wikis. * After two successful experiments, the Reader Growth team is rolling out an [[mw:Special:MyLanguage/Readers/Reader Growth/Image Browsing|Image Browsing]] beta feature for all Wikipedias on mobile on May 25. This means that anyone who has all beta features on by default will start to see this feature, and others can check the box to turn it on in their preferences. The beta feature will include a carousel of all an article's images at the top of the article, with controls for editors to [[mw:Readers/Reader_Growth/Image_Browsing#Phase_2.1_beta_feature|exclude images from the article's carousel or to exclude an article from the feature entirely]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, three dimensional STL files were being rendered incorrectly by the media viewer 3D extension which is now fixed. [https://phabricator.wikimedia.org/T416723] '''Updates for technical contributors''' * The legacy CSS classes <bdi lang="zxx" dir="ltr"><code><nowiki>tleft</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>tright</nowiki></code></bdi> have been replaced with <bdi lang="zxx" dir="ltr"><code><nowiki>floatleft</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>floatright</nowiki></code></bdi> as the former do not work consistently across all MediaWiki platforms, notably mobile web and mobile apps. Projects relying on these classes are encouraged to review related usage and plan for migration. Please note that <bdi lang="zxx" dir="ltr"><code><nowiki>floatleft</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>floatright</nowiki></code></bdi> may also be deprecated in future, although there are currently no plans to do so. [[phab:T426452|Read more]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.4|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/22|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W22"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:52, 25 May 2026 (UTC) <!-- Message sent by User:Quiddity (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30584502 --> == Tech News: 2026-23 == <section begin="technews-2026-W23"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/23|Translations]] are available. '''Updates for editors''' * The [[mw:Special:MyLanguage/Readers/Reader Experience|Reader Experience team]] is conducting an experiment to show the [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|reading lists]] feature, which is still in development, to logged-out mobile readers to test whether it encourages account creation at a higher rate compared to the watchstar button. The [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists#Experiment timeline|experiment]] was launched on May 18th on German, Spanish, Italian, Portuguese, Polish, Dutch, Turkish, and Urdu wikis, and it will run for a month. * The Wikimedia Apps team released [[mw:Special:MyLanguage/Wikimedia Apps/Team/Explore Feed Refresh/Phase 1|Phase 1]] of the redesigned Home Feed to the Android Beta app. The new Home Feed includes a refreshed "Community" tab and a personalized "For You" tab featuring daily updated reading recommendations. The redesign is part of a broader effort to improve content discovery and create more engaging learning experiences in the Wikipedia apps. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:18}} community-submitted {{PLURAL:18|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where images could fail to load for some suggested edits on [[w:Special:Homepage|Special:Homepage]], leaving the thumbnail stuck in a loading state, has now been fixed. [https://phabricator.wikimedia.org/T424048] '''Updates for technical contributors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.5|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/23|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W23"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:08, 1 June 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30613639 --> == Tech News: 2026-24 == <section begin="technews-2026-W24"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/24|Translations]] are available. '''Weekly highlight''' * Wikimedia Enterprise has increased the free usage limits for its API offerings. The monthly request limit for the On-demand API has increased from 5,000 to 50,000 requests, while the Snapshot API limit has increased from 15 to 30 requests per month. In addition, Structured Contents snapshots are now available for free accounts. These changes expand access to Wikimedia Enterprise data for developers, researchers, and organizations using Wikimedia content. [https://enterprise.wikimedia.com/blog/enhanced-free-api] '''Updates for editors''' * The [[mw:Special:MyLanguage/Wikimedia_Apps/Team/Explore Feed Refresh/Phase 1|refreshed Explore Feed]], now called the Home Feed, is rolling out to 50% of users of the Wikipedia Android app. The Home Feed helps readers discover relevant content through two new tabs: ''Community'' and ''For You''. The Community tab provides a scrollable feed of curated content and updates from the broader Wikimedia community and movement, while the ''For You'' tab offers a full-screen, swipeable experience that shows content tailored to a user's interests. The redesign is part of a broader effort to improve discovery and enhance the learning experience in the Wikipedia app. * The [[mw:Special:MyLanguage/Wikimedia Apps/Team/iOS/"Which came first?" Game|Which came first?]] daily trivia game is now available in the beta version of the Wikipedia iOS app in English, German, French, Portuguese, Russian, Spanish, Arabic, Chinese, and Turkish. The game uses historical events from Wikipedia's "On This Day" content and challenges readers to guess which of two events happened first. The game was previously released on Android. Communities interested in making the game available in their languages can [[mw:Special:MyLanguage/Wikimedia_Apps/Team/Games#Game availability by language|read the instructions and requirements]]. * [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|Sub-referencing]], a new MediaWiki feature that allows editors to reuse references with different details, will begin rolling out to Wikimedia wikis following a successful pilot phase. Deployment will start on 8 June for most [[wikitech:Deployments/Train#Wednesday|Group 1 wikis]] and French Wikipedia, with additional Wikipedia language editions receiving the feature over the coming months. Communities are encouraged to prepare by checking for [https://translatewiki.net/w/i.php?title=Special%3ATranslate&group=ext-cite&language=en&action_source=search&filter=%21translated&optional=1&action=translate untranslated Cite extension messages] in their language and reviewing any use of [[mw:Special:MyLanguage/Reference Tooltips|Reference Tooltips]], which may require [[:phab:T416304#11668731|updates]] to support the new functionality. Wikis using [[mw:Special:MyLanguage/Help:Reference Previews|Reference Previews]] do not need to take any action. Communities may also wish to create the ''cite-tracking-category-ref-details'' [[Special:TrackingCategories|tracking category]] as a hidden category using <code><nowiki>__HIDDENCAT__</nowiki></code> (or a dedicated template), and connect it to the corresponding Wikidata item [[d:Q129764848]]. [https://phabricator.wikimedia.org/T425662] * The [[mw:Special:MyLanguage/Readers/Reader Growth/Mobile page previews#Experimentation|Page Previews experiment]] on mobile web has concluded. The team decided not to roll out the feature after the results showed no statistically significant impact on reader retention, as the primary success metric was retention improvement. Page Previews, which are already available on desktop and in the apps, display a thumbnail, lead paragraph, and link to the full article when readers tap a blue link. The experiment tested this experience on mobile web across six Wikipedias. * The [[mw:Special:MyLanguage/Codex/Design/Icons|user interface icon library]] will be [[phab:T399175|updated later this week or next week]]. Most of the ~300 icons have been slightly refined and ~30 new icons have been added. These changes improve the icons to make them more consistent and comprehensible, and provide more visual balance when they are used in groups. * The [[mw:Special:MyLanguage/Universal Language Selector|Universal Language Selector]] (ULS) interface in MediaWiki, which helps users select content in other languages, has been updated. The new version improves speed and accessibility, and users of Wikimedia projects can now pin languages for quicker language switching. The deployment to Wikimedia sites will happen gradually in the coming weeks. You can test it now as a beta feature by selecting [[Special:Preferences#mw-prefsection-betafeatures|beta features]] in your profile preferences and share your feedback on [[mw:Special:MyLanguage/Universal Language Selector/New ULS|the project page]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:21}} community-submitted {{PLURAL:21|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the Pageviews Analysis dashboard on pageviews.wmcloud.org stopped updating graph data in May 2026, affecting all users, has been fixed. [https://phabricator.wikimedia.org/T427171] '''Updates for technical contributors''' * The function signature for <bdi lang="zxx" dir="ltr"><code><nowiki>mw.util.addPortletLink()</nowiki></code></bdi> has been simplified. Developers can now pass a configuration object instead of a list of positional parameters when creating portlet links. The previous function signature remains supported for backwards compatibility. For example, instead of: <bdi lang="zxx" dir="ltr"><code><nowiki>mw.util.addPortletLink('p-cactions', '#', 'Stub', 'ca-stubtag', 'Add a stub tag to this page');</nowiki></code></bdi> use <bdi lang="zxx" dir="ltr"><code><nowiki>mw.util.addPortletLink('p-cactions', { href: '#', text: 'Stub', id: 'ca-stubtag', tooltip: 'Add a stub tag to this page' });</nowiki></code></bdi>. Script maintainers are encouraged to review existing uses of <bdi lang="zxx" dir="ltr"><code><nowiki>addPortletLink()</nowiki></code></bdi> and update them where appropriate. This change will be available on all wikis from 11 June. Thanks to community volunteer Gerges for contributing this improvement. [https://phabricator.wikimedia.org/T427945] * '''Community Wishlist discussion''': Product & Technology [[m:Special:MyLanguage/Community Wishlist/Updates#May 20, 2026: Community Tech becomes a program|introduced changes]] meant to increase the number and complexity of wishes fulfilled, including the disbanding of the Community Tech team. They are [[m:Special:MyLanguage/Community Wishlist/Updates|engaging in discussions]] about a [[m:Talk:Community Wishlist#Proposed direction for Wishlist|proposed direction for the wishlist]] from community members. Includes ways to structure annual voting, better tracking of wishes, removing focus areas, and [[m:Special:MyLanguage/Community Wishlist/Updates|staffing updates]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.6|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/24|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W24"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:30, 8 June 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30650573 --> == Tech News: 2026-25 == <section begin="technews-2026-W25"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/25|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Readers/Reader Growth|Reader Growth team]] has launched an [[mw:Special:MyLanguage/Readers/Reader Growth/Image Browsing|Image Browsing]] beta feature on the mobile web version of all Wikipedias. The feature shows an image carousel at the top of articles with 3 or more images. Editors can configure this feature with the following controls: to hide a specific image from a page, either use <code>class=notpageimage</code> excluding it from thumbnail previews, or <code>class=noviewer</code> excluding it from MediaViewer. The carousel can also be disabled from a page entirely, with the magic word <code><nowiki>__NOMEDIAVIEWERCAROUSEL__</nowiki></code>. To submit feedback or flag bugs, please visit the [[mw:Talk:Readers/Reader Growth/Image Browsing|project page]]. * [[mw:Special:MyLanguage/Help:Tables#class="wikitable"|Wikitables]] can now be [[mw:Special:MyLanguage/Help:Sortable tables#Forcing the initial sort direction|sorted in descending order]] on the first click by adding <code dir=ltr>data-sort-order="desc"</code> to the header cell. Previously, by default, clicking a column header for the first time sorts it in ascending order. This addition to a Wikitable gives it more control and flexibility, while the default behavior for subsequent clicks remains unchanged. [https://phabricator.wikimedia.org/T398416] '''Updates for editors''' * The [[mw:Special:MyLanguage/Article guidance|Article guidance]] feature is currently being tested with some editors creating new articles on the Simple English, French, and Turkish Wikipedias. The experiment will soon begin on the Arabic and Bangla Wikipedias as well. [[w:simple:Special:NewArticle|This feature]] gives editors community-curated guidance to help them create articles that follow community standards. Experienced editors can continue creating or adapting outlines for specific article types that are commonly created by less experienced contributors. The outlines guide less experienced editors in creating high-quality articles. A quick guide to markups used in outlines can be found on [[mw:Special:MyLanguage/Article guidance/Test feature guide#Markups in outlines|this page]]. [[w:simple:Wikipedia:Article Guidance|Example outlines]] that can be adapted and instructions for how to adapt them are on [[mw:Special:MyLanguage/Article guidance#Adapting a sample outline in a Wikipedia|this section]] of the project page. * Wikis that wish to replace the "indefinitely" button in Special:Block for temporary accounts (for example, wikis that block temporary users only until account expiration) will be able to do so by creating [[MediaWiki:ipb-indefinite-expiry-temporary-account]] with the block duration they want. [https://phabricator.wikimedia.org/T427125] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:41}} community-submitted {{PLURAL:41|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * By the end of June, a valid user-agent string will be required for automated dumps downloads from the dumps.wikimedia.org website. Automated requests that provide a generic or empty user-agent will be blocked. This [[phab:T400119|extends enforcement]] of the long standing [[foundation:Special:MyLanguage/Policy:Wikimedia Foundation User-Agent Policy|user-agent policy]]. Access to dumps through Wikimedia Cloud Services will not change. * The roll out of global [[mw:Wikimedia APIs/Rate limits|API rate limits]] is now complete, with limits enforced across all APIs and at the documented levels for all groups. Bots running in Toolforge/WMCS or with the bot user right on any wiki remain exempt. All bots should continue to follow the documented best practices to avoid being rate limited. * The [https://api.wikimedia.org/wiki/Main_Page API Portal wiki] will be read only starting this week (June 15-18). The following week (June 22-25), all API Portal wiki URLs will redirect to [[mw:Wikimedia APIs|Wikimedia APIs on mediawiki.org]]. Learn more on the [[wikitech:API Portal/Deprecation|project page]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.7|MediaWiki]] '''Meetings and events''' * On June 17th at 6pm UTC the WMF will be holding Discord call focused on a code review. We've heard through the [[mw:Special:MyLanguage/Developer Satisfaction Survey/2026|Developer Satisfaction Survey]] that volunteers are struggling with code review and we'd like to discuss these experiences with the goal of surfacing workable solutions. You can join the call [https://discord.gg/wikipedia?event=1514727511102062664 via the Wikimedia Community Discord server]. * The [[m:Special:MyLanguage/Conferencia Wikimedia de América Latina 2026|Latin American Wikimedia Conference]] will host a regional hackathon that will bring together the Wikimedia movement’s technical community including developers, system administrators, data scientists, and users with extended rights. Interested technical contributors can [https://docs.google.com/forms/d/e/1FAIpQLSf4osJzTHBJjQbYJk7TMVEJjTEQv7IgtsUDfP-o-qTgeRQQxw/viewform apply for a scholarship] to participate until June 21 at midnight (Bolivia time, UTC-4). * Sign up for Wikimania Team Challenges to join this special event. The Team challenges will take place online and in person from July 21 to 22, before Wikimania conference. Everyone is welcome, regardless of skills or Wikimania registration. Teams will work on 10 important challenges supporting the Wikimedia community. For details, visit [[wmania:Special:MyLanguage/2026:Team challenges|the Team Challenges page]] and [https://wikimedia.eventyay.com/wm/teamchallenges/ register there]. Registration closes on June 20th at 11pm UTC. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/25|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W25"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:48, 15 June 2026 (UTC) <!-- Message sent by User:UOzurumba (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30689604 --> == Tech News: 2026-26 == <section begin="technews-2026-W26"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/26|Translations]] are available. '''Weekly highlight''' * [[mw:Special:MyLanguage/Growth/Feature summary|Growth features]] are [[phab:T418115|now available at Wikidata]]. This update enables access to Mentorship ([[mw:Special:MyLanguage/Help:Growth/Mentorship|if configured]]), Impact module, the Help Panel, and a simplified Newcomer Homepage (without Suggested Edits). Wikidata administrators are still configuring the features through Community Configuration. '''Updates for editors''' * The special page [[{{#special:RangeCalculator}}]] has been created. It allows users to find an IP range without needing to rely on external tools. Until now, this tool was only available to CheckUsers. [https://phabricator.wikimedia.org/T268429] * [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|Sub-referencing]] is a new MediaWiki feature that allows editors to reuse references with different details. It will be deployed to most small and medium-sized Wikipedia language versions on June 23. The [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#deployment|FAQ]] lists possible actions to take on your wiki to support the deployment. Check the [[:phab:T414094|rollout plan]] for the next deployment steps. [https://phabricator.wikimedia.org/T428902] * Starting next week, users will get a notification when they are blocked or unblocked from editing, or if this block changes. [https://phabricator.wikimedia.org/T100974] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:32}} community-submitted {{PLURAL:32|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * Starting next week, abuse filters that are set to "require CAPTCHA verification" will begin to also affect users with the <code>skipcaptcha</code> right, which includes most autoconfirmed users. Bots are exempted. This change only affects edits that trigger an abuse filter. The <code>skipcaptcha</code> right will continue to exempt users from having to solve CAPTCHAs in the ordinary course of using the wikis. [https://phabricator.wikimedia.org/T402595] * Reference documentation for the [[wikitech:Machine_Learning/LiftWing/API|Lift Wing API]] has moved from the API Portal to the interactive [https://wikitech.wikimedia.org/w/index.php?api=lift-wing&title=Special%3ARestSandbox REST Sandbox]. * The API Portal wiki is now closed. For API documentation, see [[mw:Special:MyLanguage/Wikimedia_APIs|Wikimedia APIs on mediawiki.org]]. All API Portal wiki URLs (https://api.wikimedia.org/wiki/) will redirect to the mediawiki.org page starting June 22. [https://phabricator.wikimedia.org/T427537] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.8|MediaWiki]] '''Meetings and events''' * Join an online call on 25 June at 2:30pm UTC to meet the current Wikimedia interns for [[mw:Google_Summer_of_Code/2026|Google Summer of Code]] and [[mw:Outreachy/Round_32|Outreachy]]. Interns will provide an overview of their projects and a brief demo of their work so far. Attendees are encouraged to [[mw:event:Google_Summer_of_Code/Summer_2026_June_Internship_open_session|share ideas and connections in their community]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/26|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W26"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 13:05, 23 June 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30722494 --> == Tech News: 2026-27 == <section begin="technews-2026-W27"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/27|Translations]] are available. '''Updates for editors''' * As part of the [[mw:Special:MyLanguage/Contributors/Account Creation Experiments|Account Creation Experiments]], the Growth team tested adding a user account icon in the mobile web header for logged-out users, providing direct access to "Create account" and "Log in" actions. The experiment increased account creation by about 20% without negatively affecting edit quality or constructive edit rates. The feature will now be rolled out to all Wikimedia Foundation wikis on mobile web in the first week of July. [https://phabricator.wikimedia.org/T428220] * After a [[phab:T426248|successful experiment]], logged-in users who did not [[mw:Special:MyLanguage/Help:Email_confirmation|confirm their email address]] when their account was created see a new banner asking them to complete that process. This helps reduce the risk that users get locked out of their account, and makes account email addresses overall more reliable. This is part of the [[mw:Special:MyLanguage/Product Safety and Integrity/Account Security|Account Security]] project. [https://phabricator.wikimedia.org/T428292] * An update to [[Special:Search|Search]] is refining how the <bdi lang="zxx" dir="ltr"><code><nowiki>-prefix:</nowiki></code></bdi> behaves when used to exclude results. Previously, using <bdi lang="zxx" dir="ltr"><code><nowiki>-prefix:</nowiki></code></bdi> with negation could unintentionally broaden search results by adding the namespaces included in the search scope, leading to confusing behavior for users expecting a straightforward exclusion filter. With the update, <bdi lang="zxx" dir="ltr"><code><nowiki>-prefix:</nowiki></code></bdi> will now strictly exclude matching page titles as intended and may display a warning if the relevant namespace has not been explicitly selected. The behavior of <bdi lang="zxx" dir="ltr"><code><nowiki>prefix:</nowiki></code></bdi> without negation however remains unchanged. [https://phabricator.wikimedia.org/T427443] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:33}} community-submitted {{PLURAL:33|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where reviewers using the Page Curation toolbar were not automatically subscribed to talk page discussions they started has now been fixed. Reviewers will now receive notifications when someone replies to those discussions. [https://phabricator.wikimedia.org/T329346] '''Updates for technical contributors''' * Starting June 29th, automated downloads from the dumps.wikimedia.org website will be subject to the [[Foundation:Special:MyLanguage/Policy:Wikimedia Foundation User-Agent Policy|user-agent policy]]. Automated requests that provide a generic or empty user-agent will be blocked. Access to dumps through Wikimedia Cloud Services remains unaffected. This is a follow up to the announcement made in the [[m:Special:MyLanguage/Tech/News/2026/25|2026/25 issue of Tech News]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.9|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/27|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W27"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 11:48, 29 June 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30744833 --> == Tech News: 2026-28 == <section begin="technews-2026-W28"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/28|Translations]] are available. '''Updates for editors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:34}} community-submitted {{PLURAL:34|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the search bar results on Wikidata, showed English results instead of using the correct language fallback for users of language variants, has now been fixed. Search suggestions will now follow the expected language fallback chain. [https://phabricator.wikimedia.org/T429769] '''Updates for technical contributors''' * In preparation for [[m:Special:MyLanguage/Event:Celebrate Women|Celebrate Women campaign]] planned for March 2027, the Wikimedia Foundation’s [[m:Special:MyLanguage/Wikimedia Foundation/Advancement/Community Growth/Content Enablement|Content Enablement team]] has launched a 22-question survey to better understand technical contributions by women+ (anyone who identifies as a woman) across Wikimedia projects. The survey takes approximately 15–20 minutes to complete and will remain open until 20 July 2026. The [[m:Special:MyLanguage/Celebrate Women/Technical contributions survey|questions]] are also available on-wiki for review in advance. * The [[mw:Special:MyLanguage/Extension:Score|Score extension]] now supports rendering music scores as SVG images in addition to PNG, addressing a long-standing [[:phab:T49578|feature request]] and resolving historical image quality issues. Both formats are now provided to clients, with PNG in the <bdi lang="zxx" dir="ltr"><code><nowiki>src</nowiki></code></bdi> attribute and SVG in the <bdi lang="zxx" dir="ltr"><code><nowiki>srcset</nowiki></code></bdi> attribute. * The new [[wikitech:Parsoid|Parsoid]] parser [[mw:Special:MyLanguage/Parsoid/Parser_Unification/Updates|continues to be deployed to additional wikis]], making it easier to introduce new reading and editing features. It was enabled on French Wikipedia, bringing total progress to covering 78.9% of Wikipedia page views. Rollout to English Wikipedia desktop will progress through this week. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.10|MediaWiki]] '''In depth''' * The Wikimedia Hackathon 2026 [[diffblog:2026/06/29/wikimedia-hackathon-2026-building-collaborating-and-shaping-the-future-together/|recap blog post]] is now live. It highlights the projects, sessions, and social activities from this year’s event, and shares initial plans for the 2027 Wikimedia Hackathon. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/28|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W28"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 13:57, 6 July 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30773578 --> == Tech News: 2026-29 == <section begin="technews-2026-W29"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/29|Translations]] are available. '''Updates for editors''' * [[mw:Special:MyLanguage/Growth/Revise_Tone|Revise Tone]] helps newcomers identify passages in Wikipedia articles that may contain non-encyclopedic language and encourages them to consider revising the tone. The feature was [[w:en:A/B_testing|A/B tested]] on the Arabic, English, French, and Portuguese Wikipedias, where newcomer task completion rates [[mw:Special:MyLanguage/Growth/Revise_Tone#Experiment_Results|increased by 38.7%]] compared to the default Copyedit task, with no decrease in edit quality. The test ended on July 9, and the feature is now available for everyone on these wikis, configurable via Community Configuration. [[phab:T426364|The plan]] is to release Revise Tone to more wikis. * The community configuration that allows [[mw:Special:MyLanguage/Help:Growth/Mentorship#Automated mentor list cleanup|automatic removal of inactive mentors]] based on configurable criteria will be enabled on Thursday 16, [[mw:Special:MyLanguage/Growth/Deployment|on some wikis]] to keep mentor lists up to date. Mentors are experienced contributors who opt in to help new users on-wiki through the [[mw:Special:MyLanguage/Growth/Feature summary|Growth Features]]. Administrators can now prepare the settings via [[w:Special:CommunityConfiguration/Mentorship|Special:CommunityConfiguration/Mentorship]]; they will take effect starting Thursday. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:38}} community-submitted {{PLURAL:38|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where some users of the Wikipedia Android app were logged out immediately after signing in, preventing them from staying logged in and editing pages, has now been fixed. [https://phabricator.wikimedia.org/T316916] '''Updates for technical contributors''' * Editing a page via user scripts or gadgets was causing watchlist labels that the user had assigned to that page to reset. This has now been fixed. [https://phabricator.wikimedia.org/T423778] * To work around a Safari bug (see [[phab:T425211]]), on Parsoid-enabled wikis, wikilink hrefs now use absolute urls instead of protocol-relative urls. REST API output remains unchanged and continue to use protocol-relative urls. Gadgets, user scripts, bots, and CSS might need to be adapted if they relied on the presence of protocol-relative urls in wikilink hrefs. [https://phabricator.wikimedia.org/T431358] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.11|MediaWiki]] '''In depth''' * The Wikimedia Foundation’s Experiment Platform Team has published a blog post reflecting on its first year of structured experimentation. It highlights successful experiments such as Paste Check, Reference Check, and Tone Check, which improved editing outcomes and have been rolled out to more users, as well as experiments that did not lead to product changes. [[diffblog:2026/07/07/moving-the-needle-how-we-test-new-ideas-across-wikimedia-projects|Read more]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/29|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W29"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 16:11, 13 July 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30804401 --> == Tech News: 2026-31 == <section begin="technews-2026-W31"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/31|Translations]] are available. '''Updates for editors''' * [[File:Maki-gift-15.svg|12px|link=|class=skin-invert|Wishlist item]] [[mw:Special:MyLanguage/ContentTranslation|Content Translation]] now supports dark mode, fulfilling a [[m:Community Wishlist/W544|Community Wishlist request]]. This brings the tool in line with the accessibility features available in the Vector 2022 and Minerva skins, helping reduce visual fatigue for users translating content. [https://phabricator.wikimedia.org/T367077] * DiscussionTools' source mode and the 2017 wikitext editor will now offer autocomplete for links (<bdi lang="zxx" dir="ltr"><code><nowiki>[[</nowiki></code></bdi>), templates (<bdi lang="zxx" dir="ltr"><code><nowiki>{{</nowiki></code></bdi>), HTML and parser tags (<bdi lang="zxx" dir="ltr"><code><nowiki><</nowiki></code></bdi>), and magic words (<bdi lang="zxx" dir="ltr"><code><nowiki>__</nowiki></code></bdi>), making it quicker and easier to insert links, templates, and other wiki markup while editing. [https://phabricator.wikimedia.org/T432400] * The [[mw:Special:MyLanguage/Readers/Reader Growth/Mobile page previews|Readers Growth team]] has concluded its experiment with mobile page previews and will not roll out the feature. Page Previews are a pop-up bottom sheet that appears when readers tap a blue link, showing a thumbnail, lead paragraph, and an option to open the article. The experiment showed flat retention and negative indicator metrics, suggesting that mobile web readers preferred navigating directly to linked articles rather than using page previews. * The Reader Experience team has seen encouraging early results from the [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists feature]], with 93% of participating users reporting that it was useful. Reading Lists help active readers save articles for future reading and support their learning goals on Wikimedia projects. The team plans further improvements before expanding the feature to more users. * The [[mw:Special:MyLanguage/Wikimedia Apps/Team/Explore Feed Refresh|Explore Feed Refresh]] initiative was tested with new and casual Wikipedia app readers. The refreshed feed helps readers discover new and relevant content. After a 10.5% increase in engagement with the feed, Wikimedia Apps team has decided to scale the Home Feed redesign to iOS with the learnings from the Android release applied. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:23}} community-submitted {{PLURAL:23|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where subject names in the Article Guidance feature were displayed with incorrect capitalization on French Wikipedia, has now been fixed. Subject names will now follow the correct capitalization rules for the language. [https://phabricator.wikimedia.org/T427201] '''Updates for technical contributors''' * After running several [[mw:Special:MyLanguage/Contributors/Account Creation Experiments|Account Creation Experiments]] to improve registration completion rates, a new version of the username field on [[Special:CreateAccount|Create Account]] has been rolled out. It includes [[:c:File:Create account - July 2026 updates.png|a popover summarizing the username policy]] to provide clearer guidance during account creation. As part of this change, the messages <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-helpusername</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-help</nowiki></code></bdi> that several communities have configured will no longer be used. If communities want to customize the guidance shown in the new popover, they can instead edit the following messages: <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-policy-popover-bullet1</nowiki></code></bdi>, <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-policy-popover-bullet2</nowiki></code></bdi>, and <bdi lang="zxx" dir="ltr"><code><nowiki>createacct-username-policy-popover-bullet3</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T430604] * Later this week, the [[mw:Special:MyLanguage/Help:Extension:CodeMirror|CodeMirror syntax highlighter]] will offer [[w:en:Theme (computing)|themes]]. The themes can be picked from a dropdown menu in the full [[mw:Special:MyLanguage/Help:Extension:CodeMirror#CodeMirror preferences|CodeMirror preferences]] dialog. For wikitext, available themes are default, colorblind-friendly (previously the colorblind preference option on [[Special:Preferences#mw-prefsection-editing]]) and no-highlighting. For code languages (i.e., CSS/JavaScript/JSON/Vue/Lua), there are several themes available. These same themes will eventually be available for wikitext, too. [https://phabricator.wikimedia.org/T163533] * From now on, wikis can restrict editing in the "User" namespace to only the page owner and certain user groups. [[mw:Special:MyLanguage/Manual:$wgRestrictUserPageEditing|Read the configuration documentation]] to learn more. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.14|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/31|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W31"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:49, 27 July 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30856308 --> == Tech News: 2026-32 == <section begin="technews-2026-W32"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/32|Translations]] are available. '''Updates for editors''' * The [[mw:Special:MyLanguage/Readers/Reader Experience|Reader Experience team]] has developed a [https://82db7c8d4b.catalyst.wmcloud.org/w/index.php?title=Regent%27s_Park&uselang=de patch demo] that wraps the page toolbar onto two lines when there is not enough horizontal space for all the buttons. This aims to reduce crowding in the Vector 2022 toolbar, which can occur on some language Wikipedias at certain screen widths. [https://phabricator.wikimedia.org/T429518] * The Reader Experience team is planning to launch [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]], a [[m:Special:MyLanguage/Community Wishlist Survey 2021/Mobile and apps/Have Apps reading lists available on Destop/Mobile|Community Wishlist item]], which is currently available to try in beta, as a full feature in September. Before then, volunteer translator help is needed for [https://translatewiki.net/w/i.php?title=Special%3ATranslate&group=ext-readinglists&filter=&action=translate string translations] into a number of languages. The feature supports reading and learning goals on Wikipedia. * Next week, the table of contents on Wikimedia Commons file pages will be improved by consolidating the file page table of contents with the page table of contents. This will make it easier to understand a file page’s structure, navigate to specific sections, and share links to individual sections. [https://phabricator.wikimedia.org/T332644] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:24}} community-submitted {{PLURAL:24|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where some [[w:TIFF|TIFF]] images failed to load after clicking their thumbnail, causing a broken image to be displayed instead of the full-size image, has now been fixed. [https://phabricator.wikimedia.org/T429326] '''Updates for technical contributors''' * The variable and function selector in AbuseFilter has been updated to support search and autocomplete. It will allow filter maintainers to find the desired variable or function more quickly. [https://phabricator.wikimedia.org/T323698] * The MJPEG and VP8 formats are removed from the video player. The MP4 format (MPEG-4 Part 2) is added instead, which provides higher quality videos to older iPhone devices. It may take a few weeks to retroactively update all existing videos. The default format for modern devices stays the same (VP9/WebM). [https://phabricator.wikimedia.org/T358266] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.15|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/32|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W32"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 19:46, 3 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30872536 --> == Tech News: 2026-33 == <section begin="technews-2026-W33"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/33|Translations]] are available. '''Updates for editors''' * [[File:Maki-gift-15.svg|12px|link=|class=skin-invert|Wishlist item]] A new ChartWizard is [[c:Special:ChartWizard/Data:Example.Pie.chart|now available on Wikimedia Commons]] for users interested in creating charts from their own data. The wizard makes the [[mw:Special:MyLanguage/Extension:Chart|Chart extension]] more beginner-friendly by allowing editors to create charts, such as bar and pie charts, without needing to use JSON. Users can still switch to the JSON editor if they prefer. Feedback on the new tool is welcome on the [[m:Talk:Community Wishlist/W414|wish talk page]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:19}} community-submitted {{PLURAL:19|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the Wikipedia iOS app’s Picture of the Day widget displayed the same image every day instead of updating daily, has now been fixed. [https://phabricator.wikimedia.org/T430692] '''Updates for technical contributors''' * [[mw:Special:MyLanguage/Extension:Math|Math formula]] SVG images will soon be generated in the browser instead of on the server. MathML continues to be generated on the server and renders in the browser without JavaScript. Wikibooks will see this change on 12 August, Wikisource on 19 August and Wikipedia from 20-27 August. You can try this by selecting "{{int:Mw-math-mathjax}}" in your preferences. This change is part of [[mw:Special:MyLanguage/RESTBase/deprecation|deprecating RESTBase]] and [[phab:T431372|deprecating Mathoid]]. [https://phabricator.wikimedia.org/T271001] * Category pages will soon support sorting entries by the time they are added to a category. This will make it easier to find recently or long-standing categorized pages. It will also improve workflows for maintenance categories such as deletion backlogs and other time-based review tasks. You can use <bdi lang="zxx" dir="ltr"><code><nowiki>cldsort=timestamp</nowiki></code></bdi> URL argument in category view to sort the entries. [https://phabricator.wikimedia.org/T433768] * [[mw:Special:MyLanguage/Extension:Gadgets|Gadgets]] and user scripts on Wikimedia wikis may now use [[phab:T395347|ES2018 features]] and [[phab:T419142|ES2019 features]] in JavaScript code. Previously, the platform only allowed up to ES2017. MediaWiki validates the source code to protect functionality from syntax errors and to ensure scripts are valid in all [[mw:Special:MyLanguage/Compatibility#Browser_support_matrix|supported browsers]]. [https://phabricator.wikimedia.org/T419142] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.16|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/33|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W33"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:45, 10 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30901051 --> == Tech News: 2026-34 == <section begin="technews-2026-W34"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/34|Translations]] are available. '''Weekly highlight''' * The [[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Registration/Worklist|Worklist feature]] for the Event Registration tool is now live on all Wikimedia wikis. With Worklist, event organizers can add the articles their event will focus on directly to the event page. The Worklist also powers [[mw:Special:MyLanguage/Help:Extension:CampaignEvents/Registration/Worklist#How Event Pathways uses the worklist|Event Pathways]] which notifies other editors of the upcoming or ongoing event when they edit an article featured in the event's Worklist. This is the minimum viable version (MVP), and feedback is welcome. Organizers are encouraged to try the feature. A hands-on [[m:Special:MyLanguage/Event:Worklist Setup Workshop: Get Your Event Ready|Worklist Setup Workshop]] will take place on 18 August at 16:00 UTC and 19 August at 11:00 UTC. '''Updates for editors''' * [[Special:ShortPages]] displays short pages by their size, but in many cases it gets filled with disambiguations and soft redirects, making it harder to find the short articles themselves. Starting this weekend, you will be able to choose not to include an article in the special page by adding the magic word <bdi lang="zxx" dir="ltr"><code><nowiki>__EXPECTSHORTPAGE__</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T433203] * One new wiki has been created: a {{int:project-localized-name-group-wikipedia/en}} in [[d:Q3436680|Bole]] ([[w:bol:|<bdi lang="zxx" dir="ltr"><code><nowiki>w:bol:</nowiki></code></bdi>]]) [https://phabricator.wikimedia.org/T429921] * Starting the week of August 17, the page toolbar will wrap onto two lines when there is not enough horizontal space for all the buttons. This is a [[phab:T429518|fully merged patch from the Reader Experience team]] which aims to reduce crowding in the Vector 2022 toolbar, that may occur on some language Wikipedias at certain screen widths. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:16}} community-submitted {{PLURAL:16|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, uploading large files to Wikimedia Commons has become more stable and less prone to failure following some fixes related to the “Could not acquire lock” upload error. [https://phabricator.wikimedia.org/T386640] '''Updates for technical contributors''' * Debian Bullseye will reach the end of its Long Term Support on 31 August 2026. [[phab:T434103|Some Cloud VPS projects]] still have instances running Debian Bullseye. Maintainers of those projects are encouraged to migrate to Debian Bookworm or Debian Trixie. A [[wikitech:Help:Cloud VPS instance operating system migration|migration guide]] is available to help with the process, and users may also want to consider whether their workload is better suited to Toolforge. If you need help or cannot complete the migration by 31 August, please contact the Cloud VPS admins as soon as possible. [[listarchive:list/cloud-announce@lists.wikimedia.org/thread/RVIPQSYLKMSL5M46JP6NEJVGVE6I2RXQ/|Read more]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.16|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/34|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W34"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 21:03, 17 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30922806 --> == Tech News: 2026-35 == <section begin="technews-2026-W35"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/35|Translations]] are available. '''Updates for editors''' * The [[Special:CreateAccount|Special:CreateAccount]] page has been simplified as part of ongoing work to modernize the account creation experience. The panel showing project statistics no longer appears next to the form on desktop and mobile web. Multiple account creation experiments show that a simpler form helps newcomers complete registration. [https://phabricator.wikimedia.org/T433783] * In order to improve page performance, images now load when they are viewed. This means images lower down an article will not load if a reader never scrolls to that part of the page, which may affect some image-related metrics. [https://phabricator.wikimedia.org/T148047] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:42}} community-submitted {{PLURAL:42|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where image thumbnails in Abstract Wikipedia could fail to display after the corresponding file was moved on Wikimedia Commons, has now been fixed. Thumbnails will now update correctly when files are moved. [https://phabricator.wikimedia.org/T433448] '''Updates for technical contributors''' * User Info card is a feature that helps patrollers see information about user accounts. So far, it has been available only in places such as page history, logs and recent changes. Now, it's possible to [[mw:Special:MyLanguage/Help:Extension:CheckUser#User_Info_card_in_page_content|place it in the page content]] as well, using the <bdi lang="zxx" dir="ltr"><code><nowiki>{{#uic:}}</nowiki></code></bdi> parser function. It can be particularly useful in templates like [[:en:Template:Userlinks|<bdi lang="zxx" dir="ltr"><code><nowiki>{{Userlinks}}</nowiki></code></bdi>]] (or their specialized variants), as it will make it easier to see the context about a user on various noticeboard pages. The card will be displayed only to users who have it enabled in their [[Special:Preferences#mw-input-wpcheckuser-userinfocard-enable|preferences]]. [https://phabricator.wikimedia.org/T424466] * Due to user security and privacy risks, we have disabled access to <bdi lang="zxx" dir="ltr"><code><nowiki>Special:MyPage</nowiki></code></bdi> URLs when specifically using <bdi lang="zxx" dir="ltr"><code><nowiki>action=raw</nowiki></code></bdi>. If you are impacted by this, consider whether you can use an alternative approach. <bdi lang="zxx" dir="ltr"><code><nowiki>Special:MyPage</nowiki></code></bdi> URLs can still be accessed and used without <bdi lang="zxx" dir="ltr"><code><nowiki>action=raw</nowiki></code></bdi>. Specified user page URLs (e.g. <bdi lang="zxx" dir="ltr"><code><nowiki>User:Myusername</nowiki></code></bdi>) can still be used with <bdi lang="zxx" dir="ltr"><code><nowiki>action=raw</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T120386] * Due to an update, the thumbnailing software has been improved. This includes upgrading <bdi lang="zxx" dir="ltr"><code><nowiki>librsvg</nowiki></code></bdi> to 2.60 and <bdi lang="zxx" dir="ltr"><code><nowiki>ImageMagick</nowiki></code></bdi> to 7, as well as resolving a number of long-standing thumbnailing bugs like rendering errors. [https://phabricator.wikimedia.org/T419815#12222841] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.17|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/35|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W35"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:45, 24 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30961208 --> == Tech News: 2026-36 == <section begin="technews-2026-W36"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/36|Translations]] are available. '''Weekly highlight''' * A new format for the Community Wishlist is open for feedback. You can [[m:Special:MyLanguage/Community Wishlist/Community Wishlist 2027|read the proposed ideas on Meta]]. This new process plans to improve how wishes are triaged, voted on, and prioritized in a way that is transparent and balanced across project families and language editions. This consultation is open for two weeks. '''Updates for editors''' * The latest release of the Wikipedia Android app includes updates to the Saved feature, bringing the app’s saving experience closer to iOS and Web. The update redesigns the Saved tab with an “All articles” view, removes the default “Saved” reading list, renames reading lists to “Collections,” and modernizes the article-saving experience. [https://phabricator.wikimedia.org/T420788] * The [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]] feature was enabled for all logged-in users on Bengali, Chinese, Czech and Vietnamese Wikipedias on August 25, after several months as a beta feature. Reading Lists will be available to all logged-in users on Arabic, French and Indonesian Wikipedias on September 1, followed by English Wikipedia on September 14, and all other Wikipedia wikis on September 28. * At the end of the month, some logged-out readers on Bengali, Czech, Persian, English, and Polish Wikipedias using the Minerva skin on mobile will see an [[mw:Special:MyLanguage/Readers/Reader_Growth/Minimal_Minerva|updated navigation bar]] in an [[w:A/B test|A/B test]]. The test will compare the current navigation bar with a new version designed to make it easier to find information more quickly. The goal is to determine whether these changes encourage readers to return more often. This experiment will not change the experience for logged-in readers and/or editors. * Editors who maintain redirects, templates, and categories used on redirect pages now have improved ways for finding and curating redirects. Previously, redirects pages could not be searched. Two new search keywords, <bdi lang="zxx" dir="ltr"><code><nowiki>onlyredirects:</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>withredirects:</nowiki></code></bdi>, now allow redirects to be searched directly and can be combined with existing keywords such as <bdi lang="zxx" dir="ltr"><code><nowiki>incategory:</nowiki></code></bdi>, <bdi lang="zxx" dir="ltr"><code><nowiki>intitle:</nowiki></code></bdi>, and <bdi lang="zxx" dir="ltr"><code><nowiki>insource:</nowiki></code></bdi>. [https://phabricator.wikimedia.org/T204089] * The ISBN lookup tools for generating citations were recently not working because of external service problems. Developers are working on solutions. [https://phabricator.wikimedia.org/T435179] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:30}} community-submitted {{PLURAL:30|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where searching for pages by category using <bdi lang="zxx" dir="ltr"><code><nowiki>deepcat</nowiki></code></bdi> could return no results or unrelated results has now been fixed. [https://phabricator.wikimedia.org/T414859] '''Updates for technical contributors''' * The domain of URLs for thumbnails is changing from upload.wikimedia.org to thumb.wikimedia.org. The old URLs will continue to work for the foreseeable future but MediaWiki will advertise the new domain instead. URLs to other types of media such as original files, videos and transcodes will still be served from upload.wikimedia.org. [https://phabricator.wikimedia.org/T427465] * The Wikimedia [https://www.mediawiki.org/w/index.php?api=wmf-math%2Fv1&title=Special%3ARestSandbox Math API] is now deprecated. These endpoints will be fully sunset by the end of September 2026. Developers who call these endpoints should transition to alternative math rendering solutions, such as the native [https://developer.mozilla.org/en-US/docs/Web/MathML MathML] or [https://www.mathjax.org/ MathJax]. Third-party MediaWiki installations that utilize the Math extension for formula rendering are required to upgrade to v1.43+ to avoid disruption of service. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.18|MediaWiki]] '''In depth''' * Read more about [[mw:Special:MyLanguage/Edit_check/TextMatch|TextMatch]] in a Diff post titled, [[diffblog:2026/08/28/custom-edit-suggestions-for-every-wiki-how-communities-are-shaping-suggestion-mode-with-textmatch/|Custom edit suggestions for every wiki: How communities are shaping Suggestion Mode with TextMatch]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/36|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W36"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 20:53, 31 August 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=30990659 --> == Tech News: 2026-37 == <section begin="technews-2026-W37"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/37|Translations]] are available. '''Updates for editors''' * [[mw:Special:MyLanguage/Help:Growth/Tools/Add_a_link|Add a Link]] has been upgraded for English Wikipedia users with improved detection of links that have different capitalization. This will help reduce ambiguous suggestions caused by differences in capitalization in article titles, including articles about cultural goods. A second phase of improvements is planned, which will also prepare the feature for release in other languages. [https://phabricator.wikimedia.org/T435526#12240876] [https://phabricator.wikimedia.org/T434259] * The [[mw:Special:MyLanguage/Article_guidance|Article guidance]] feature will be enabled by default for junior editors on Simple English and Turkish Wikipedia starting 10 September 2026 following [[mw:Special:MyLanguage/Article_guidance/Updates#Summary_of_experiment_result|an experiment]]. Junior editors with 0 to 99 edits will automatically see the feature when they click a red link or use the "[[tr:Vikipedi:Madde_sihirbazı|Madde oluşturto]]" option on Turkish Wikipedia to create a new article. The change is intended to help junior editors create higher-quality articles that meet each Wikipedia’s standards. [[phab:maniphest/query/z3tcTjmLMxk5/#R|Additional improvements]] will continue based on the experiment results and community feedback. * The [https://pageviews.wmcloud.org Pageviews Analysis] tool which allows users to compare pageviews across multiple pages, turns 10 years old this year and several new features have been added. They include [[toolforge:wikinav|WikiNav]] which provides insights into how readers of Wikipedia explore the content, editing stats in [https://pageviews.wmcloud.org/siteviews?range=latest-30&sites=en.wikipedia.org Siteviews], the ability to [https://pageviews.wmcloud.org/massviews?source=wikiproject&project=en.wikipedia.org lookup articles belonging to a WikiProject], and support for dark mode. [https://phabricator.wikimedia.org/T378549] * A [[mw:Special:MyLanguage/Readers/Reader_Growth/Minimal_Minerva|visually simplified Minerva]] navigation bar is being tested for logged-out readers using mobile web on the Bengali, Czech, English, Farsi, and Polish Wikipedias. The experiment aims to determine whether simplifying the navigation improves reader retention. The test will run from August 31 to September 28, and no action is required from users. * [[m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]] is working on improving [[en:Wikipedia:VisualEditor/Named references|auto-generated reference names in VisualEditor]]. Editors will only notice a slight change starting this week. When adding automatic reference names the numbering will start at <bdi lang="zxx" dir="ltr"><code><nowiki>:1</nowiki></code></bdi> instead of <bdi lang="zxx" dir="ltr"><code><nowiki>:0</nowiki></code></bdi>. Read more on the [[m:WMDE Technical Wishes/References/VisualEditor automatic reference names|project page]]. [https://gerrit.wikimedia.org/r/c/VisualEditor/VisualEditor/+/1332704] * All wikis will be [[m:Special:MyLanguage/Tech/Server switch|read-only for a few minutes]] on September 23. This is planned at 14:00 UTC. More information will be published in Tech News and will also be posted on individual wikis in the coming weeks. [https://phabricator.wikimedia.org/T433363] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:25}} community-submitted {{PLURAL:25|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where [[mw:Special:MyLanguage/Parsoid|Parsoid]] could mishandle nested nowiki tags, causing content to be lost and displaying unwanted text has now been fixed. [https://phabricator.wikimedia.org/T435116] '''Updates for technical contributors''' * Interface administrators can configure gadgets from [[MediaWiki:Gadgets-definition]]. The definition format has been updated and no longer requires the <bdi lang="zxx" dir="ltr"><code><nowiki>ResourceLoader</nowiki></code></bdi> option, as gadgets are always loaded through <bdi lang="zxx" dir="ltr"><code><nowiki>ResourceLoader</nowiki></code></bdi>. This simplifies gadget configuration by removing an option that is no longer necessary, making gadget definitions easier for administrators. [https://phabricator.wikimedia.org/T298199] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.19|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/37|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W37"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:44, 7 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31008437 --> == Tech News: 2026-38 == <section begin="technews-2026-W38"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/38|Translations]] are available. '''Weekly highlight''' * The Future Audiences team has started a [[en:Special:MyLanguage/Wikipedia:Village pump (proposals)#New proposed experiment to let readers know about “Google preferred sources”|discussion on English Wikipedia]] about a proposed new experiment to show a temporary notice about the new [https://blog.google/products-and-platforms/products/search/original-high-quality-content-search/ Google Preferred Sources] feature to Wikipedia readers coming from Google. The experiment is to test whether this notice makes visitors come back to Wikipedia more often. Preferred Sources feature lets users choose websites they trust so Google can highlight content from those sources more prominently in Search and AI experiences. We are interested in testing this on other languages that Google supports and would welcome assistance with starting conversations on other wikis. If interested, please reach out to Future Audiences on the [[m:Special:MyLanguage/Future Audiences/Preferred sources|talk page]]. '''Updates for editors''' * The chat platform Discord is releasing a new self-service framework that websites can use to specify how their links should look when shared on Discord. The Future Audiences team is planning to start using this new framework to improve how Wikipedia links look when shared on Discord, giving better attribution and credit to contributors. The link appearance and behavior won't change in the first phase of this project as we want to first collect some baseline data to assess the impact of future changes. However, if community members who are active on Discord spot any issues, they can reach out on [[phab:tag/future-audiences/|Phabricator]] or [[m:Special:MyLanguage/Future Audiences|Metawiki]]. * The Reader Growth team will be running an experiment to test whether [[mw:Special:MyLanguage/Readers/Reader_Growth/Compact Lead|compacting article lead sections on mobiles]] with the addition of a "read more" button improves reader retention. The test will begin on September 17 on Arabic, Spanish, French, Indonesian, Italian, Japanese, Portuguese, Vietnamese, and Chinese Wikipedias and will run for four weeks. * All wikis will be [[m:Special:MyLanguage/Tech/Server switch|read-only for a few minutes]] on September 23. This is planned at 14:00 UTC. More information will be published in Tech News and will also be posted on individual wikis in the coming week. [https://phabricator.wikimedia.org/T433363] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where [https://wikistats.wmcloud.org/ Wikistats] for Wikipedias was returning an HTTP 500 error and could not be reached, has now been fixed. [https://phabricator.wikimedia.org/T435959] '''Updates for technical contributors''' * Developers who maintain a tool that queries the Wikimedia Commons links tables need to update their code to connect to the new x4 database cluster. The links tables have been moved from the s4 cluster to x4, and will no longer receive updates on s4. The page and redirect tables remain available on both clusters. A wiki replica for the x4 cluster will be set up afterwards. The change is being made because the s4 cluster has grown too large to operate efficiently. You can [[wikitech:Special:MyLanguage/News/2026 Commons links tables database split|read more]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.20|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/38|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W38"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 15:31, 14 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31039826 --> == Tech News: 2026-39 == <section begin="technews-2026-W39"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/39|Translations]] are available. '''Weekly highlight''' * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on Wednesday, 23 September 2026 at [https://zonestamp.toolforge.org/1790172000 14:00 UTC]. This is for the datacenter server switchover backup tests, [[wikitech:Special:MyLanguage/Deployments/Yearly calendar|which happen twice a year]]. During the switchover, all Wikimedia website traffic is shifted from one primary data center to the backup data center to test availability and prevent service disruption even in emergencies. [https://phabricator.wikimedia.org/T433363] '''Updates for editors''' * The Growth team tested a new post-edit notice designed to [[mw:Special:MyLanguage/Contributors/Account Creation Experiments#4. Encourage Temporary Accounts to Register|encourage Temporary Account holders to register for a permanent account]]. The new notice replaced multiple dialogs and a simultaneous welcome notification with a single message highlighting the benefits of creating an account. The experiment increased permanent account creation from 1.94% to 3.66%, an 87% relative increase. The change will now be released to all wikis. [https://phabricator.wikimedia.org/T433551] * For Wikipedia editors using the [[Special:Preferences#mw-prefsection-betafeatures|"Suggestion mode" Beta Feature]], there is a [[Special:Preferences#mw-input-wpvisualeditor-editcheck-experimental|new opt-in user preference]] for showing "experimental" edit checks and suggestions. These types are listed at [[Special:EditChecks#experimental-checks|Special:EditChecks]], and are intended for early developer-testing and for gathering feedback from experienced users. Administrators can change the [[mw:Special:MyLanguage/Edit check/Configuration|configuration details]] for each suggestion as usual. Administrators can also [[mw:Special:MyLanguage/Help:Suggestion mode#Experimental Suggestions|use this feature]] to help test their community's ideas for locally created checks and suggestions. Experimental types will have a more distinct visual style later this week. [[mw:Talk:VisualEditor/Suggestion Mode|Feedback is welcome]]. * The [[m:CEE Technical Village Pump|CEE Technical Village Pump]] has been launched as a space for technical discussions and collaboration among Wikimedia communities in Central and Eastern Europe. * A new tool, [[mw:Special:MyLanguage/Language Onboarding and Development/Starter kit|Starter Kit]], is now available for new and small language Wikipedia communities. It brings together guided tasks, tools, and resources to help communities get started, monitor their progress, and collaborate with the broader Wikimedia community. Starter Kit is hosted on Wikimedia Toolforge and is designed for Wikipedias with fewer than 50,000 articles. Learn more about how Starter Kit works and how communities have been using it in [[diffblog:2026/09/18/introducing-starter-kit-for-new-and-small-language-wikipedias/|this Diff blog post]]. * The Reader Growth team is launching a retest of the [[mw:Special:MyLanguage/Readers/Reader Growth/Image Browsing|image carousel experiment]]. The retest will use three new versions of the design, updated based on community feedback. The team will assess results and determine with communities whether or not to proceed with the feature. The experiment will begin the week of September 28 and will run on Arabic, Bengali, Chinese, Czech, English, Farsi, French, German, Indonesian, Japanese, Polish, Portuguese, Spanish, Swedish, and Vietnamese Wikipedias. * After successful rollouts to Arabic, Bengali, Chinese, Czech, English, French, Indonesian, and Vietnamese Wikipedias, the [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists feature]] from the Reader Experience team will be available to all logged-in users on all Wikipedia wikis starting September 28. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where the mentor status script repeatedly updated mentors’ status even when nothing had changed, creating unnecessary Recent Changes entries, has now been fixed. [https://phabricator.wikimedia.org/T436659] '''Updates for technical contributors''' * The <bdi lang="zxx" dir="ltr"><code><nowiki>abusefilters</nowiki></code></bdi> list query API, used to retrieve specific details about active or historical abuse filters configured on a wiki, has been updated to support the <bdi lang="zxx" dir="ltr"><code><nowiki>formatversion=2</nowiki></code></bdi> configuration parameter, thereby leading to breaking changes to the API response. All users who maintain user-scripts or other code need to check if they use the <bdi lang="zxx" dir="ltr"><code><nowiki>abusefilters</nowiki></code></bdi> list query API, and respond to any breaking changes. [https://phabricator.wikimedia.org/T435828] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.21|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/39|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W39"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 11:56, 27 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31085309 --> == Tech News: 2026-40 == <section begin="technews-2026-W40"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/40|Translations]] are available. '''Updates for editors''' * Users of default skins on desktop and mobile web (Vector 2022 and Minerva respectively) will now be informed if the search suggestions displayed as they type into Search come from page redirects. Previously, users could get confused when the top search suggestions did not match exactly what they had typed. The new redirect notice clarifies that these suggestions are not random, but related to the search. The suggested pages may be redirects to the most relevant destination articles being searched for. [https://phabricator.wikimedia.org/T303013] * Logged-out Wikipedia users on mobile web will begin to see a bookmark button for saving articles to their [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|reading lists]] instead of the current Watchstar button. When clicked, the bookmark button prompts users to log in or create an account to save an article for later. An earlier experiment found that the bookmark icon was four times more likely than the Watchstar button to encourage logged-out users to create an account. This change is part of efforts to encourage more readers to become account holders and use features that help them save and return to content. [https://phabricator.wikimedia.org/T438769] * An experiment will begin on September 29 on Spanish, Arabic, English, and French Wikipedias to simplify the experience users encounter immediately after account creation. The test will explore whether removing friction from the current Welcome Survey helps new users understand what to do next more easily. The experiment will run through the end of October. [https://phabricator.wikimedia.org/T430058] * The [[m:Special:MyLanguage/Product and Technology Advisory Council|Product and Technology Advisory Council]] has put out a call for the community to suggest topics that it should consider and discuss with the Wikimedia Foundation. Editors and technical contributors are invited to add topics to [[m:Talk:Product and Technology Advisory Council|the council's talk page]]. * Later this week, it will be possible for communities to configure [[mw:Special:MyLanguage/Help:Edit check|Edit Checks and Suggestions]] so that they are [[mw:Special:MyLanguage/Edit check/Configuration#extraNamespaces|shown within additional namespaces]], such as a <bdi lang="zxx" dir="ltr"><code><nowiki>Draft:</nowiki></code></bdi> namespace. [[mw:Talk:VisualEditor/Suggestion Mode|Feedback is welcome]]. * A bug in the [[m:Special:GlobalWatchlist|Global Watchlist]] is causing the page to fail to load for users that have unseen changes on Wikimedia Commons. Developers are working on a fix. Until then, affected users can follow the workarounds described in the [[mw:Special:MyLanguage/Extension:GlobalWatchlist#GlobalWatchlist temporarily broken for users with Wikimedia Commons|relevant]] help section. * New magic words <bdi lang="zxx" dir="ltr"><code><nowiki>{{CATEGORYSORT:TIMESTAMP}}</nowiki></code></bdi> and <bdi lang="zxx" dir="ltr"><code><nowiki>{{CATEGORYSORT:RTIMESTAMP}}</nowiki></code></bdi> are now available for use. They are able to change the default sorting of categories to be based on timestamp of categorization. [https://phabricator.wikimedia.org/T433768] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:20}} community-submitted {{PLURAL:20|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where [https://wikistats.wmcloud.org/ Wikistats] for Wikipedias was not reachable has now been fixed. [https://phabricator.wikimedia.org/T435959] '''Updates for technical contributors''' * The datacenter switchover, scheduled on September 23, has been postponed. [[diffblog:2025/03/12/hear-that-the-wikis-go-silent-twice-a-year/|The equinox exercise]] revealed capacity issues, preventing the switch of all services to the other datacenter. The process has been paused, prioritizing investigating that issue, to ensure that we continue to be able to serve our users reliably. A new exercise will be scheduled. Meanwhile, all traffic and edits continue to work as usual. * On September 23, a power loss briefly affected all wikis, creating intermittent issues on both reading and editing modes. This also affected Gerrit. This is unrelated to the datacenter switchover postponement. [https://www.wikimediastatus.net/incidents/9fm19t8qykk8] * [[mw:Special:MyLanguage/Help:Extension:Produnto|Produnto]] has been deployed to mediawiki.org and [[phab:T421436|some Indic language wikis]]. We want to hear your feedback on this experimental product. Produnto allows users to use Lua modules hosted in [[gitlab:repos/lua|Wikimedia's GitLab]]. It simplifies the sharing of Lua code between wikis. Instead of copying each individual Lua module from one wiki to another, users will be able to easily share packages across all wikis. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.22|MediaWiki]] '''Meetings and events''' * A [[m:Event:Cross-wiki Code Collaboration Workshop|Cross-wiki code collaboration workshop]] will be held online on October 2 at 12:30 UTC, bringing together South Asian technical contributors to learn about Produnto and begin piloting it on Hindi, Punjabi, Odia, Telugu, and Malayalam Wikipedias. Produnto is a package manager for deploying Lua modules hosted on GitLab to Wikimedia wikis, and was recently deployed on some pilot wikis. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/40|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W40"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 10:49, 28 September 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31092225 --> == Tech News: 2026-41 == <section begin="technews-2026-W41"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/41|Translations]] are available. '''Weekly highlight''' * The process for this year’s Community Wishlist [[m:Special:MyLanguage/Community Wishlist/Community Wishlist 2027#Updated Community Wishlist Process 2027/2028|has been published]], incorporating community feedback. The wish submission process will [[m:Special:MyLanguage/Community Wishlist/FAQ#What is the deadline for submitting wishes?|end on November 8]]. This year, [[m:Special:MyLanguage/Community Wishlist/Community Wishlist 2027/Working group|a working group (open for volunteering)]] that includes community members familiar with the technical aspect of our wikis alongside Wikimedia Foundation staff, will take care of the [[m:Special:MyLanguage/Community Wishlist/FAQ#What is triage?|triage process]]. The triage is expected to be completed by late November. Votes for wishes will start in January. '''Updates for editors''' * Editors using the [[mw:Special:MyLanguage/VisualEditor|visual editor]] will now see a warning when they paste text that is likely to have initially been copied from one of five external generative AI chatbots into Wikipedia. This feature is known as [[mw:Special:MyLanguage/Edit check/LLM Paste Check|LLM Paste Check]]. It is a type of [[mw:Special:MyLanguage/Edit check|Edit Check]] that is community configurable. The check looks for markers in the copied HTML and is not using content watermark detection. Edits will also [[mw:Special:MyLanguage/Edit check/LLM Paste Check#Edit tags|be tagged]] so that patrollers can review them more closely. The feature helps newcomers add content that respects Wikipedia’s policies and makes it easier for experienced editors to identify problematic edits. Communities with local policies about LLM usage can [[mw:Special:MyLanguage/Edit check/LLM Paste Check#Configuration|adjust the wording and policy that is linked]]. The team [[listarchive:list/translators-l@lists.wikimedia.org/message/EVHKWJ4IERZELMPIWNH3XUVUSQV5KOO4/|apologizes]] that this was rolled out without a delay for translations. * Editors can now easily [[mw:Special:MyLanguage/Wikimedia Apps/Team/Future of Editing on the Mobile Apps|access the web visual editor directly from the iOS and Android apps]]. When opening the editor, users will be given a choice between visual editing and source editing. If they choose visual editing, they will be sent to a mobile web window in their phone's browser. After completing their edit, a banner will give them the option to return to the app. This enables readers to make quick contributions while casually reading. * Users of the Wikipedia Android and iOS apps will now see a one-time account creation prompt after they have used the app for two consecutive weeks. This prompt explains the benefits of having an account. It is intended to help more casual readers become logged-in users who return to the apps regularly. [https://phabricator.wikimedia.org/T434847] * Editors on [[wmnoc:conf/dblists/group1.dblist|group1 wikis]], including Wikiquote, Wikibooks, Wikiversity, Wikivoyage, and Wikisource, will no longer see notifications on [[mw:Special:MyLanguage/Help:Recent changes|Recent Changes]] and [[mw:Special:MyLanguage/Help: Watching pages|Watchlist]] when a link to another language version of a page is added, removed, or changed in its Wikidata item. This change will begin on October 5 at 07:00 UTC as a two-week trial to reduce high-volume, low-value notifications and make important changes easier to identify. Editors who rely on these notifications can read more on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project page]] and share feedback or concerns on the [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]]. [https://phabricator.wikimedia.org/T439415] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:36}} community-submitted {{PLURAL:36|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where mentors who removed themselves from the mentorship program could still have mentees assigned to them and receive questions, has now been fixed. Mentees will now be reassigned when a mentor leaves the program. [https://phabricator.wikimedia.org/T418194] '''Updates for technical contributors''' * Wikimedia Brasil has published its [[m:Special:MyLanguage/Wikimedia Brasil/Arcabouço de Boas Práticas de Desenvolvimento|Development Best Practices Framework]] (ABPD). It is a guide for staff, contractors and volunteers building technical tools and projects. It covers the project lifecycle, security, accessibility, personal data protection and responsible AI use, and explains how movement-wide guidelines were adapted to a local context. They encourage other affiliates to reuse it and adapt it. Read more in the [[wmfblog:2026/09/26/wikimedia-brasils-development-best-practices-framework-technical-sustainability-as-an-organizational-responsibility|Diff post]]. * A new, canonical base URL for Wikimedia APIs will soon be introduced. The new canonical route follows a <bdi lang="zxx" dir="ltr"><code><nowiki>{projectName}/api/</nowiki></code></bdi> pattern and will act as an alternative path for current REST APIs (for example: <bdi lang="zxx" dir="ltr"><code><nowiki>{projectName}/w/rest.php/</nowiki></code></bdi>). Both versions will be callable for all existing APIs, but the new structure will be the preferred path for newly created API modules. This change will be non-breaking for most users. The existing pathways will remain available for all existing endpoint requests. However, some endpoints may return URLs following the new pattern in response bodies. Changes will be available on test wiki first, with the rollout expected to cover all wikis by the end of October. [https://phabricator.wikimedia.org/T433535] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.23|MediaWiki]]. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/41|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W41"/> 18:52, 5 October 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31098825 --> == Tech News: 2026-42 == <section begin="technews-2026-W42"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/42|Translations]] are available. '''Weekly highlight''' * Starting October 13, wikis can change the default pattern for [[:en:Wikipedia:VisualEditor/Named references|auto-generated reference names in VisualEditor]] (currently <syntaxhighlight lang="wikitext" inline><ref name=":1" /></syntaxhighlight>). They will be able to use human-readable, content-based reference names that are more helpful to contributors using the source editor (e.g. <syntaxhighlight lang="wikitext" inline><ref name="Miller2026-1" /></syntaxhighlight>). VisualEditor reference name patterns can be defined using MediaWiki system messages, JSON, templates and modules ([[:mw:Special:MyLanguage/Help:Cite/VisualEditor reference names|more information]]). Admins can enable these changes via [[Special:CommunityConfiguration/Cite-VisualEditor-Autonames|community configuration]]. This is a [[:m:Special:MyLanguage/Community_Wishlist/W17|community wish]] implemented by [[:m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]]. [https://phabricator.wikimedia.org/T436255] * [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing|Sub-referencing]] is a new MediaWiki feature that allows editors to reuse references with different details. It will be deployed to English Wikipedia on October 14 and to remaining Wikimedia Foundation wikis by end of October (likely October 21). The [[m:Special:MyLanguage/WMDE Technical Wishes/Sub-referencing#deployment|FAQ]] lists possible actions to take on your wiki to support the deployment. This is a [[:m:WMDE Technical Wishes/Sub-referencing/History|long-standing community wish]] implemented by [[:m:Special:MyLanguage/WMDE Technical Wishes|WMDE Technical Wishes]]. [https://phabricator.wikimedia.org/T440243][https://phabricator.wikimedia.org/T440304] '''Updates for editors''' * [[mw:Special:MyLanguage/Moderator Tools|Moderator Tools]] will be removing the list view of the Watchlist and defaulting everyone to the changelog view. Previously, there were two versions of how the Watchlist is shown to mobile web users: the list view, where editors could see watched articles in a list format, and the changelog view, where editors could see changes to watched articles in a log format, controlled by a user's Advanced Mobile Control settings. This has created issues for code-base maintenance: two different displays means two sets of code to manage. By defaulting to the changelog view, we are simplifying the codebase and avoiding the likelihood of missing bugs. * The Wikipedia Android app is testing a way to listen to article introductions in the “For you” feed. A text-to-speech model reads the existing article text aloud without rewriting it or adding any content. The 30-day experiment will begin in the Wikipedia Beta app during the third week of September, then move to the regular Wikipedia Android app in October for a limited group of eligible users. A small portion of app users (those with English feeds and at least one topic interest) will have access to the feature. This experiment is part of broader efforts to give app readers options in how they consume content in order to deepen engagement and user retention. [[mw:Special:MyLanguage/Readers/Listening to Wikipedia/Phase 1|Learn more]] and [[mw:Talk:Readers/Listening to Wikipedia|share feedback]]. * [[mw:Special:MyLanguage/Help:Extension:CodeMirror|CodeMirror syntax highlighting]] was [[phab:T288161|enabled]] by default for all logged out and newly registered users on the English Wikipedia on September 14. With no signs of adverse effects, the same change is being proposed to be made globally across all wikis in a few weeks. If you have concerns or feedback, or if your wiki would like to opt out, [[mw:Special:MyLanguage/Help talk:Extension:CodeMirror#Enabling CodeMirror by default on all WMF wikis for newbies|please see the help page]]. [https://phabricator.wikimedia.org/T440077] * [[d:Wikidata:Usability_and_usefulness/Item_editing_experience/Mobile_editing_of_statements|Wikidata mobile statement editing]] of all datatypes will be officially launched on October 13, when it will be removed from Wikidata [[d:Special:Preferences#mw-prefsection-betafeatures|beta features]] and become available to all editors. Users can [[d:Wikidata_talk:Usability_and_usefulness/Item_editing_experience/Mobile_editing_of_statements|report bugs and share feedback]]. * Last week, language link changes were removed from [[Special:RecentChanges|Recent Changes]] and [[Special:Watchlist|Watchlist]] feeds on Wikivoyage, Wikisource, Wikiversity, Wikiquote and Wiktionary. As no adverse effects have been observed, the [[m:Wikidata_For_Wikimedia_Projects|Wikidata For Wikimedia Projects]] plans to roll out this change globally to all Wikipedias. This is scheduled for October 13 at 07:00 UTC, after which editors will no longer see when a link to ''another'' language version of a page is added, removed, or changed in its Wikidata item. Editors who rely on these notifications can read more on the [[m:Wikidata For Wikimedia Projects/Clearer Wikidata Edit Summaries/Hide Language Link edits|project page]] and share feedback or ask to opt out their wiki on the [[m:Talk:Wikidata_For_Wikimedia_Projects/Clearer_Wikidata_Edit_Summaries/Hide_Language_Link_edits|talk page]]. [https://phabricator.wikimedia.org/T440698] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:28}} community-submitted {{PLURAL:28|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where accidentally touching the graph while scrolling on the Pageviews tool on mobile could unintentionally zoom in has now been fixed. Click-and-drag zoom is now disabled on touch devices. [https://phabricator.wikimedia.org/T440075] '''Updates for technical contributors''' * There are three major changes coming to dumps: the legacy content dumps [https://lists.wikimedia.org/hyperkitty/list/xmldatadumps-l@lists.wikimedia.org/thread/E6D5EU4PMSTSOI2J7A46HJ3YW2W554CS/ deprecated in January 2026] will now be sunset, the replacement [https://wikitech.wikimedia.org/wiki/MediaWiki_Content_File_Exports MediaWiki Content File Exports] will be delayed to implement a “safety buffer”, and they are now also available as 7zip-compressed files. Users will need to switch the URL they download their dump from. For more information, timeline and migration instructions, see [https://wikitech.wikimedia.org/wiki/Legacy_content_dumps_sunset Legacy content dumps sunset]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.47/wmf.24|MediaWiki]] '''In depth''' * The Wikimedia Foundation discovered unauthorized activity by OpenAI agents on Wikimedia projects, including edits to wikis, attempts to exploit a public note-taking tool, and heavy automated traffic. [[diffblog:2026/10/05/openai-rogue-agent-activities-found-on-wikimedia-projects/|Read the blog post on Diff]] for more details about the activity and the Foundation’s response. '''Meetings and events''' * Save the date for the next Wikimedia Hackathon! We’ll be meeting in lovely Tirana, Albania for the [https://www.mediawiki.org/wiki/Wikimedia%20Hackathon%202027 2027 Wikimedia Hackathon] from April 9–11, 2027. Scholarship and staff sponsorship applications are currently being [https://pretix.eu/wikimedia/Hackathon-2027/ accepted through Pretix] and will close on October 30, 2026. General registration will open in January 2027. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/42|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W42"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 07:40, 13 October 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31142468 --> == Tech News: 2026-43 == <section begin="technews-2026-W43"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/43|Translations]] are available. '''Updates for editors''' * To measure the impact of incorporating some [[mw:Special:MyLanguage/Readers/Reader_Growth/Image_Browsing#November 2025: Ideas and feedback|community-requested features]] on logged-out reader retention, a test for [[mw:Special:MyLanguage/Readers/Reader_Growth/Image_Browsing|Image Carousel]] will be pushed to logged-out readers. With the Image Carousel feature, readers browse community-uploaded images, selected by editors as relevant to specific articles. The test starts on November 20. * An experimental notice will be pushed to 0.5% of logged-out mobile readers who come to English Wikipedia from Google, asking them to add Wikipedia as a [https://blog.google/products-and-platforms/products/search/preferred-sources/ Google Preferred Source]. The test is to see if this notice increases reader retention and encourages people who use Google Search to visit Wikipedia more often. It will run from October 15–29 and will be assessed for its impact on retention and referrals. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:26}} community-submitted {{PLURAL:26|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where [[quarry:|Quarry]] returned an “Access denied” error when users tried to run SQL queries, preventing queries from running normally, has now been fixed. [https://phabricator.wikimedia.org/T440966] '''Updates for technical contributors''' * [[File:Cog-icon-grey.svg|12px|link=|class=skin-invert|Advanced item]] Due to a long-standing bug, applications that use the [[mw:Special:MyLanguage/OAuth/For_Developers|OAuth 2]] client credentials flow to act on their owners’ behalf are treated as if they are logged out. This will be fixed for new applications registered on or after Monday, October 19. Some affected applications need to re-register. [https://phabricator.wikimedia.org/T420297] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.1|MediaWiki]] '''Meetings and events''' * A proposal to hold the Wikimedia Hackathon every three years, with regional hackathons in between, [[mw:Wikimedia Hackathon/Community Proposal 2026|has been shared]]. It explores making the event more accessible to technical communities in different regions. Share your feedback on the proposal’s [[mw:Talk:Wikimedia Hackathon/Community Proposal 2026|talk page]] before November 6. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/43|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W43"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:38, 19 October 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31178499 --> == Tech News: 2026-44 == <section begin="technews-2026-W44"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/44|Translations]] are available. '''Weekly highlight''' * An experiment launched on September 29 is testing [[mw:Special:MyLanguage/Readers/Reader_Experience/Reading_recommendations|article recommendations]] for new account holders who also identify as readers. By suggesting articles to read, similar to recommendations in the Wikipedia app for logged-in readers, the experiment aims to encourage new account holders to read and return to the website regularly, with the goal of increasing internal referrals by 1%. See the related [[m:Community Wishlist/W505|Community Wishlist]] proposal. * Several Wikimedia services were taken offline last week because of a [https://www.php.net/archive/2026.php#2026-10-20-1 security vulnerability in PHP]. This is because they need to be updated before they are safe to put back online. This is not a problem just for the Wikimedia movement but affects a lot of websites. You can follow updates on [[wikitech:Incidents/2026-10-21 PHP security update/Community|Wikitech]]. Cloud VPS and Toolforge will take longer to bring back online. This is to make sure that applications which run on Cloud VPS or Toolforge are not affected. Tool developers can see updates and more information on the [https://lists.wikimedia.org/postorius/lists/cloud-announce.lists.wikimedia.org/ Cloud-announce mailing list]. [https://diff.wikimedia.org/2026/10/21/impact-of-php-vulnerabilities-on-wikimedia-tools-and-services/][https://diff.wikimedia.org/2026/10/21/impact-of-php-vulnerabilities-on-wikimedia-cloud-services/] * [[m:Special:MyLanguage/Tech/News/2026/43|Last week we shared]] that to measure the impact of incorporating some community-requested features on logged-out reader retention, a test for the [[mw:Special:MyLanguage/Readers/Reader Growth/Image Browsing|Image Carousel]] feature would be pushed to logged-out readers. Due to an issue, we will be restarting the test, but it will be live on October 26, not November 20 as initially announced. '''Updates for editors''' * A new [[wikitech:KAPOW|bot detection system]] to better identify automated traffic that disguises itself as human visitors, is coming to the Wikimedia wikis. This might cause sudden changes to visitor statistics starting from 26 October, going back to 20 June 2026. * The [[mw:Special:MyLanguage/Extension:Score|Score extension]] which renders musical notation inside wiki pages, has been temporarily disabled on all wikis due to a security issue. Affected pages will display a notice instead of musical scores, but the underlying code remains intact. No action is needed from editors, and a fix is in progress. A separate announcement will follow when the extension is re-enabled. Read more on [[phab:T441579|Phabricator]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:18}} community-submitted {{PLURAL:18|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, the issue where CodeMirror syntax highlighter appears to have been enabled in error for existing editors has been fixed. [https://phabricator.wikimedia.org/T441308] '''Updates for technical contributors''' * [[m:Special:MyLanguage/Tech/Server switch|All wikis will be read-only]] for a few minutes on Wednesday, October 28 2026 at [https://zonestamp.toolforge.org/1793199600 15:00 UTC]. This is for the datacenter server switchover backup tests, [[wikitech:Deployments/Yearly calendar|which happen twice a year]]. During the switchover, all Wikimedia website traffic is shifted from one primary data center to the backup data center to test availability and prevent service disruption even in emergencies. [https://phabricator.wikimedia.org/T439703] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.2|MediaWiki]] '''Meetings and events''' * Scholarship and sponsorship applications for the [https://www.mediawiki.org/wiki/Wikimedia%20Hackathon%202027 2027 Wikimedia Hackathon] will close on Friday, October 30th. Submit your application [https://pretix.eu/wikimedia/Hackathon-2027/ through Pretix] before the deadline! '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/44|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W44"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 18:56, 26 October 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31199592 --> == Tech News: 2026-45 == <section begin="technews-2026-W45"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/45|Translations]] are available. '''Weekly highlight''' * Many Wikimedia tools were taken offline last week because of a [[:w:PHP2Shell|security vulnerability in PHP]]. This affected many websites worldwide. [[m:Special:MyLanguage/Toolforge|Toolforge]] and [[m:Special:MyLanguage/Wikimedia Cloud Services|Cloud VPS]] have been back up since October 22. Many important tools have been gradually restored. Some tools need the respective volunteer maintainers to restart them. Others still need to upgrade to a patched PHP version. Some tools were using older versions of PHP which are not supported by the recent security patches. They will require maintainers to upgrade to a more recent version. This might require additional effort. You can follow the work [[:wikitech:Talk:Incidents/2026-10-21 PHP security update/Community#Exceptions|on Wikitech]]. '''Updates for editors''' * A new optional search experiment is running in the Wikipedia Android and iOS apps for Arabic, French, and Japanese Wikipedias. Participating readers can search inside articles and open quoted passages directly in their source articles, no answers or summaries are generated. This is the first of four experiments in [[mw:Special:MyLanguage/Readers/Information%20Retrieval/Phase%202|Phase 2 of Semantic Search]]. It began on October 22 and runs for 20 days. Feedback is welcome on the project’s [[mw:Special:MyLanguage/Talk:Readers/Information%20Retrieval/Phase%202|discussion page]]. * The [[m:Special:MyLanguage/Future_Audiences|Future Audiences]] team is planning to bring [[m:Special:MyLanguage/Future_Audiences/Share_card|Share Cards]] to Wikipedia on mobile. This feature gives users the option to share a visually appealing card with friends, based on the article they are reading. The card contains the article’s title, image, opening text, and related attribution, and links back to the article for full reading. Editors are invited to try out this feature by adding <code dir="ltr">?useformat=mobile&sharecard=1</code> to any article URL from October 29 to November 8. Share any thoughts on the [[m:Talk:Future_Audiences/Share_card| project talk page]] and report any bugs on [[phab:T439161|Phabricator]]. * The default renderer for math formulas will change on November 2. After the change, the server sends the formula as MathML, and your browser uses MathJax to show it. This is the last step towards the Mathoid/RESTBase deprecation process, for sustainability and security reasons. You can [[w:en:Wikipedia:WikiProject Mathematics/MathFormattingBugs|ask questions or report problems]]. [https://phabricator.wikimedia.org/T375238] * Do you have an idea for a new feature, or a bug that needs fixing? [[m:Special:MyLanguage/Community Wishlist|Submit your suggestion for the community wish list by November 8!]] * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:41}} community-submitted {{PLURAL:41|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. '''Updates for technical contributors''' * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.3|MediaWiki]] '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/45|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W45"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 14:23, 3 November 2026 (UTC) <!-- Message sent by User:Trizek (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31236748 --> == Tech News: 2026-46 == <section begin="technews-2026-W46"/><div class="plainlinks"> Latest '''[[m:Special:MyLanguage/Tech/News|tech news]]''' from the Wikimedia technical community. Please tell other users about these changes. Not all changes will affect you. [[m:Special:MyLanguage/Tech/News/2026/46|Translations]] are available. '''Weekly highlight''' * The Wikipedia Apps team is preparing to launch Year in Review in early December. Year in Review gives app users a personalized recap of how they read and engaged with Wikipedia throughout the year. The team is looking for volunteers to help make it available in as many languages as possible. Translators can contribute through [https://translatewiki.net/ translatewiki.net]. For [https://translatewiki.net/w/i.php?title=Special:Translate&action=translate&group=out-wikimedia-mobile-wikipedia-android-strings&filter=%21translated Android], search for <bdi lang="zxx" dir="ltr"><code><nowiki>yir</nowiki></code></bdi> under the "Untranslated" tab, and for [https://translatewiki.net/w/i.php?title=Special:Translate&action=translate&group=out-wikimedia-mobile-wikipedia-ios&filter=%21translated&optional=1 iOS], search for <bdi lang="zxx" dir="ltr"><code><nowiki>year-in-review</nowiki></code></bdi> under the "Untranslated" tab. * The [[mw:Special:MyLanguage/Article guidance|Article guidance]] feature that helps editors create articles that follow a Wikipedia’s policies, is now available on all Wikipedias. Administrators and interface admins can configure and expose it for editors to use via [[Special:CommunityConfiguration/ArticleGuidance]]. A [[mw:Special:MyLanguage/Article guidance/Community Configuration|configuration guide is available]]. Visit [[mw:Talk:Article guidance|the project talk page]] to ask any questions. '''Updates for editors''' * Following the release of [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists|Reading Lists]] to all Wikipedias in September, logged-in users will soon be able to [[mw:Special:MyLanguage/Readers/Reader Experience/Reading lists#October/November 2026: Custom collections and call to action|organize articles saved in their lists into customizable categories]]. This will enable readers to create collections and revisit saved articles based on their interests, potentially encouraging frequent visits to Wikipedia. The update will roll out to all Wikipedia users between November 9 and 16. * The Wikipedia Apps team is preparing to launch the first of two notification experiments for English Wikipedia readers on Android who have opted in to notifications. The three-week experiment will send notifications suggesting personalized Discover reading lists which are collections of Wikipedia articles recommended based on articles the reader has previously viewed. The goal is to understand whether these recommendations help readers discover relevant content and encourage them to return to the app. No action is required, and users can manage their notification preferences in the app settings. [[mw:Wikimedia Apps/Team/Notifications|Learn more and share feedback]]. * A bug in the [[m:Special:GlobalWatchlist|Global Watchlist]] was causing the page to fail to load for users who have unseen changes on Wikimedia Commons. The bug has now been fixed. If you temporarily removed <bdi lang="zxx" dir="ltr"><code><nowiki>commons.wikimedia.org</nowiki></code></bdi> from your personal [[m:Special:GlobalWatchlistSettings|Global Watchlist settings]] due to the bug, you can restore it there. [https://phabricator.wikimedia.org/T439203] * A new Beta feature called "Home" will be [[mw:Special:MyLanguage/Home/Deployment|deployed to 10 Wikipedias]] for a limited test. This new feature aims to replace <bdi lang="zxx" dir="ltr"><code><nowiki>Special:Homepage</nowiki></code></bdi> for newcomers, with additional modules planned for the future to improve upon the current experience. If you want to participate in the test, please [[mw:Talk:Home|sign up]]. "Home" will be released to all users later this month. * On English and Russian Wikipedias, [[m:User:Alaexis/Source Verifier|Source Verification]] is now available as an experimental Suggestion for experienced editors within [[mw:Special:MyLanguage/VisualEditor/Suggestion_Mode|Suggestion Mode]]. It uses an LLM hosted on [[wikitech:Machine_Learning/LiftWing|LiftWing]] to try to check whether a cited source supports the claim it’s attached to. To try it out, please [[phab:T426359|see these testing instructions]]. If you are at another language Wikipedia and your community is interested in trying it out, please [[m:User talk:Alaexis/Source Verifier|express your interest]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] View all {{formatnum:35}} community-submitted {{PLURAL:35|task|tasks}} that were [[m:Special:MyLanguage/Tech/News/Recently resolved community tasks|resolved last week]]. For example, an issue where dates passed as blank parameters to functions in wikitext were incorrectly interpreted using the month-day-year format instead of the day-month-year format, has now been fixed. [https://phabricator.wikimedia.org/T403884] '''Updates for technical contributors''' * Starting on 1 December 2026, hCaptcha will be required for edits made via the API by non-autoconfirmed users. If your tool, gadget, or user script makes edits on behalf of newcomer users, [[mw:Special:MyLanguage/Product Safety and Integrity/hCaptcha#November 2026: Completing hCaptcha rollout|see how to update it]]. * [[wikitech:Help talk:Toolforge/Toolforge standards committee#November 2026 committee nominations|Nominations are open on Wikitech]] for new [[wikitech:Help:Toolforge/Toolforge standards committee|Toolforge standards committee]] members. The committee oversees the Toolforge [[wikitech:Help:Toolforge/Right to fork policy|Right to fork policy]] and [[wikitech:Help:Toolforge/Abandoned tool policy|Abandoned tool policy]] among other duties. Nominations close on 22 November 2026. * Toolforge has introduced two new beta features. "Toolforge alerts" send email notifications when a tool becomes unavailable, returns errors, or restarts frequently. "Extended logging" makes it easier to investigate problems by providing logs for events such as job creation, deletion, and deployment failures through the <bdi lang="zxx" dir="ltr"><code><nowiki>toolforge logs</nowiki></code></bdi> command. Both features are opt-in and help tool maintainers become aware of and resolve problems with their tools more quickly. Maintainers can [[wikitech:Help:Toolforge/Alerts|enable alerts]] and learn how to [[wikitech:Help:Toolforge/Running_jobs#Toolforge_logs|access extended logs]]. They are also encouraged to try the features and [[wikitech:Help:Cloud_Services_communication|provide feedback]]. * [[File:Reload icon with two arrows.svg|12px|link=|class=skin-invert|Recurrent item]] Detailed code updates later this week: [[mw:MediaWiki 1.48/wmf.4|MediaWiki]] '''Meetings and events''' * A proposal to change how we currently organize the Wikimedia Hackathon [[mw:Special:MyLanguage/Wikimedia Hackathon/Community Proposal 2026|has been shared]]. It explores making the event more accessible to technical communities in different regions. Share your feedback on the proposal’s [[mw:Special:MyLanguage/Talk:Wikimedia Hackathon/Community Proposal 2026|talk page]]; the deadline has been extended to November 13th. '''''[[m:Special:MyLanguage/Tech/News|Tech news]]''' prepared by [[m:Special:MyLanguage/Tech/News/Writers|Tech News writers]] and posted by [[m:Special:MyLanguage/User:MediaWiki message delivery|bot]]&nbsp;• [[m:Special:MyLanguage/Tech/News#contribute|Contribute]]&nbsp;• [[m:Special:MyLanguage/Tech/News/2026/46|Translate]]&nbsp;• [[m:Tech|Get help]]&nbsp;• [[m:Talk:Tech/News|Give feedback]]&nbsp;• [[m:Global message delivery/Targets/Tech ambassadors|Subscribe or unsubscribe]].'' </div><section end="technews-2026-W46"/> <bdi lang="en" dir="ltr">[[User:MediaWiki message delivery|MediaWiki message delivery]]</bdi> 10:34, 9 November 2026 (UTC) <!-- Message sent by User:STei (WMF)@metawiki using the list at https://meta.wikimedia.org/w/index.php?title=Global_message_delivery/Targets/Tech_ambassadors&oldid=31249348 --> ctpjhchv37741sqn3lfupihkn0hqp3m 0 264381 2844920 2842887 2026-11-09T01:13:38Z Scogdill 1331941 2844920 wikitext text/x-wiki [[File:Viscount Mandeville Vanity Fair 1882-04-22.jpg|alt=Old drawing for a magazine of an aristocratic man in a formal suit|thumb|"Kim," Viscount Mandeville, 1882]] == Overview == === Kim Montagu, Viscount Mandeville, 8th Duke of Manchester === The Mandeville who was in a relationship with music-hall and vaudeville star Bessie Bellwood was Kim (George Victor Drogo) Montagu, 8th Duke of Manchester (17 June 1853 – 18 August 1892). He was Viscount Mandeville from 18 August 1855 (when his grandfather died) to 22 March 1890 (when his father died).<ref name=":1" /> His father was the 7th Duke and his mother was [[Social Victorians/People/Louisa Montagu Cavendish|Louise Cavendish]], "double Duchess" of [[Social Victorians/People/Manchester|Manchester]] and then [[Social Victorians/People/Devonshire|Devonshire]]. In 1882 Viscount Mandeville (right) was "Man of the Day" (#255) for ''Vanity Fair'', drawn by Leslie Ward ("Spy").<ref>"Viscount Mandeville Vanity Fair 1882-04-22.jpg." Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Viscount_Mandeville_Vanity_Fair_1882-04-22.jpg (retrieved 8 September 2026).</ref> Kim Montagu, Lord Mandeville ended the relationship with Bessie Bellwood sometime during 1890, presumably after acceding to the dukedom. In November of 1890, his son secretly married Helena Zimmerman. === Consuelo Yznaga, Viscountess Mandeville, Duchess of Manchester === Consuelo Yznaga, Viscountess of Mandeville was an American heiress, daughter of a Cuban diplomat and businessman and a white southern aristocrat, and the first of 3 Iznaga sisters to marry a British peer. She took fees for getting Americans presented at court and for getting them introduced to the Prince of Wales, in whose social network she took active part. She does not appear to have attended the [[Social Victorians/1897 Fancy Dress Ball|Duchess of Devonshire's 1897 fancy-dress ball at Devonshire House]], although her mother in law was hostess and her eldest son was present. == Also Known As == *Family name: Montagu *The title Viscount Mandeville is a courtesy title for the heir apparent and eldest son of the [[Social Victorians/People/Manchester |Duke of Manchester]]. This title is one of only 2 (for the heir apparent of a duke) that is below the rank of Earl (the other is the heir apparent of the Duke of Somerset). (Is Mandeville a toponym?) *Viscount Mandeville **"Kim" (George Victor Drogo) Montagu [8th Duke], (18 August 1855 – 22 March 1890) **[[Social Victorians/People/William Angus Drogo Montagu|William Angus Drogo Montagu]], 9th Duke (22 March 1890 – 18 August 1892) **Alexander George Francis Drogo Montagu (2 October 1902 – 9 February 1947)<ref>{{Cite journal|date=2020-10-15|title=Alexander Montagu, 10th Duke of Manchester|url=https://en.wikipedia.org/w/index.php?title=Alexander_Montagu,_10th_Duke_of_Manchester&oldid=983660353|journal=Wikipedia|language=en}}</ref> *Viscountess Mandeville **Consuelo Iznaga y Clement Montagu [8th Duchess] (22 May 1876 – 22 March 1890) **Helena Zimmerman Montagu (14 November 1890 – 18 August 1892) *Lord Kimbolton (Baron Kimbolton of Kimbolton is the courtesy title for the heir presumptive, the heir apparent's eldest son, so the son of Viscount Mandeville<ref>{{Cite journal|date=2026-09-21|title=Duke of Manchester|url=https://en.wikipedia.org/w/index.php?title=Duke_of_Manchester&oldid=1375987697|journal=Wikipedia|language=en}}</ref>) ** [[Social Victorians/People/William Angus Drogo Montagu|William Angus Drogo Montagu]], 9th Duke (1877 – 22 March 1890) == Acquaintances, Friends and Enemies == === "Kim" Montagu, 8th Duke, Lord Mandeville until 1890 === ==== Friends ==== * Edward Russell, 24th Baron de Clifford * Derrick Westenra, 5th Baron Rossmore * Francis Needham, 3rd Earl of Kilmorey === Consuelo Iznaga y Clement Montagu === ==== Friends ==== *Consuelo Iznaga y Clement Montagu was in the intimate circle of [[Social Victorians/People/Albert Edward, Prince of Wales |Albert Edward, Prince of Wales]]. ==Organizations== === "Kim" Montagu, 8th Duke, Lord Mandeville until 1890 === * Eton<ref name=":1" /> === Consuelo Iznaga y Clement Montagu === * Consuelo Iznaga y Clement Montagu was a member of the New York City social set called the Buccaneers when she was a teenager.<ref name=":0">{{Cite journal|date=2020-10-06|title=Consuelo Montagu, Duchess of Manchester|url=https://en.wikipedia.org/w/index.php?title=Consuelo_Montagu,_Duchess_of_Manchester&oldid=982192002|journal=Wikipedia|language=en}}</ref> Edith Wharton is said to have taken details from the 8th Duke's marriage for her novel ''The Buccaneers''.<ref name=":1">{{Cite journal|date=2020-10-06|title=George Montagu, 8th Duke of Manchester|url=https://en.wikipedia.org/w/index.php?title=George_Montagu,_8th_Duke_of_Manchester&oldid=982188929|journal=Wikipedia|language=en}}</ref> == Timeline == '''1855 August 18''', the 6th Duke died. The families "placed in mourning" were the following, as listed in the ''Edinburgh Evening Post and Scottish Record'':<blockquote>He is succeeded in the Dukedom by his eldest son, Viscount Mandeville, M.P. By the melancholy event the families of the Marquess and Marchioness of Tweeddale, the Duchess of Wellington, the Duke of Montrose, Lord and Lady Olivia Ossulston [?], Lady Eliza [Elisa?] Steele, the Duke of Richmond, the Countess of St Germans, Lady Sophia Cecil, and many others of rank, are placed in mourning.<ref>"Death of the Duke of Manchester." ''Edinburgh Evening Post and Scottish Standard'' 22 August 1855, Wednesday: 2 [of 4], Col. 5c [of 8]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001177%2F18550822&page=2&article=025&stringtohighlight=mandeville+viscount. Print title ''Edinburgh Evening Post and Scottish Record''; n.p.</ref></blockquote>'''1855 October 11, Wednesday''', H. I. Cridland says in a "Notice,"<blockquote>I will hold Audit Days at Lyttelton, on Wednesday, 11th October, for the receipt of rents and other monies due to the 25th of September, on account of the Soames, Jackson, Ecclesiastical, and Lyttelton Trust Estates, the lands of Lord Mandeville, Lady Emily Bathurst, Lady Olivia Sparrow, Rev. J. P. Rhoades, Rev. Charles Hodge, Dr. Merrion C. T. Maunsell, George Hart, late William Draper, and J. E. Fitz Gerald, Esqrs. ... Tenants are requested to present their last receipt.<ref>"Notice." ''Lyttelton Times'' 6 October 1855, Saturday: 1 [of 10], Col. 3c [of 3]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0003346%2F18551006&page=1&article=004&stringtohighlight=mandeville+viscount. Newspaper title ''The Lyttelton Times'', n.p. </ref></blockquote>This notice was repeated in the ''Lyttelton Times'' on 29 December 1855. '''1855 October 20, Saturday''', the [[Social Victorians/People/Wilton|Earl and Countess of Wilton]] hosted a [[Social Victorians/Timeline/1850s#1855 October 20, Saturday|house party at Heaton Hall]], with a visit to a silk mill in town. [[Social Victorians/People/Louisa Montagu Cavendish|Luise, Duchess of Manchester]] was present with the Duke and their son Lord Mandeville (Kim, later 8th Duke), who was 2 years old. '''1876 May 22''', Consuelo Iznaga y Clement and "Kim" (George Victor Drogo, 8th Duke) Montagu married in Grace Church, New York City.<ref name=":0" /> === 1880s === '''1889 December 23''', Lord Mandeville attended a [[Social Victorians/Boxing/Smith-Slavin 1889-12-23|boxing match in Bruges, Belgium between British Champion Jem Smith and Australian Champion Frank Slavin]]. The English boxer Smith had "roughs" to make sure he did not lose the fight, so it ended dishonestly and with violence. The social fallout was enormous. Besides attacking Slavin, the "ruffians" also threatened men in the audience: "One rough made a rush for Lord Mandeville just before the close, but 'Kim' soon showed he could hold his own with the 'boy,' who beat a hasty retreat at the 'sight' of six-inch 'Jack.'"<ref name=":2">"The Great Fight. Smith & Slavin for £1000. Disorderly Proceedings. Brutal Attack on Slavin. Smith Knocked Down Repeatedly. He Leaves the Ring. A Draw Declared after 14 Rounds." ''The Sportsman'' 24 December 1889, Tuesday: 3 [of 4], Col. 1a – 4, Col. 6c [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001055%2F18891224&page=3&article=057&stringtohighlight=mandeville+viscount. Same print title and p.</ref> (4, Col. 1a) One man who attended the fight described this to a reporter for ''The Sportsman'': "One rough, more venturesome than the others, "framed" [sic double quotes] up to a familiar figure at boxing tournaments, but on the latter producing a long bowie knife, accompanied with a few words of a somewhat emphatic nature, the villain rejoined his party."<ref name=":2" /> (4, Col. 2b) [The "jack" is apparently a knife, suggesting that Mandeville carried a 6-inch blade with him sometimes.] === 1890s === '''1890 January 1, Wednesday, New Year's Day''', the [[Social Victorians/Timeline/1890#Marchioness of Londonderry's "At Home"|Marchioness of Londonderry]] [[Social Victorians/Timeline/1890#Marchioness of Londonderry's "At Home"|hosted an "At Home" on New Year's Day for 700–800 people]], including people from local neighborhoods. Lady Mandeville was invited, but the Viscount's name is not listed. '''1890 January 5, Sunday''', Viscount Mandeville is mentioned in a [[Social Victorians/Timeline/1890#"A Very Bad Lot"|rant in Reynolds's Newspaper called "A Very Bad Lot,"]] talking about immoral practices in the aristocracy. '''1890 January 6, Monday''', Lady Mandeville was present at [[Social Victorians/Timeline/1890#11 January 1890, Saturday|Merton with a small party and the Prince of Wales]] during the funeral of Empress Augusta. Also on Monday, 6 January 1890, Viscount Mandeville took part in a [[Social Victorians/Timeline/1890#Amicable Gathering of Boxers and Sportsmen|gathering to see "Parson" Davies off on his trip to the US]]. The gathering was amicable, Slavin was there. '''1890 January 10, Friday''', Lady Mandeville was invited to a [[Social Victorians/1890-01-10 Ulster Club Ball|ball at the Ulster Club, Belfast]]. The article in the ''Lady's Pictorial'' says the "principal families in the north of Ireland were invited,"<ref>"Court and Society Notes." ''Lady's Pictorial'' 18 January 1890, Saturday: 44 [of 60], Col. 1b [of 3]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0005980%2F18900118&page=44. Same print title, p. 94.</ref> but Lord Mandeville is not mentioned. '''1890 January 13, Monday''', Lord Mandeville was an organizer of a [[Social Victorians/Timeline/1890#Wallace-Camp Boxing Match|boxing match between "Nunc" (Edwin) Wallace and George Camp]]. This match was important and Wallace was very important in the history of this sport. Lord Mandeville was also reported to be at an [[Social Victorians/Boxing/Smith-Slavin 1889-12-23|unfair and notorious match in Bruges between a British and an Australian fighter]] that occurred on 23 December 1889. '''1890 January 14, Tuesday, probably, or January 7''', Lord Mandeville was "attacked" in a restaurant by a boxer:<blockquote>The "Evening Post" states that Charles Mitchell, the pugilist, attacked Lord Mandeville and Mr Abington at a West-End restaurant on Tuesday night. They were immediately separated.<ref>''Aberdeen Press and Journal'' 15 January 1890, Wednesday: 6 [of 8], Col. 4b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000032%2F18900115&page=6&article=097&stringtohighlight=mandeville+viscount. Print title: ''The Aberdeen Weekly Journal'', p. 6.</ref></blockquote>'''1890 January 21, Tuesday''', on or about, Lady Mandeville attended the [[Social Victorians/Timeline/1890#1890 January 21, Tuesday|wedding of Baron S. Alfred Oppenheim and Miss Florence Hutchins]]. '''1890 January 28, Tuesday''', Lady Mandeville attended what was supposed to be [[Social Victorians/People/Lily Langtry#1890 January 28, Tuesday|Lily Langtry's opening-night performance at the St. James's]] with the Prince of Wales and some of his circle. Also on this date, the ''Dundee Evening Telegraph'' reported that Lady Mandeville [[Social Victorians/Timeline/1890#1890 January 28, Tuesday|had bought 30 "Exploration" shares]], which funded exploration expeditions with the possibility of rights to minerals or resources or the development of monopolies for goods that were "discovered."<ref>"Notes — Mainly Personal." ''Dundee Evening Telegraph'' 28 January 1890, Tuesday: 2 [of 4], Col. 2b [of my 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000453%2F18900128&page=2&article=001&stringtohighlight=mandeville+viscount. Print title: ''Evening Telegraph'', n.p.</ref> Her mother in law, [[Social Victorians/People/Louisa Montagu Cavendish|Louisa, Duchess of Manchester]] also had bought 30 shares, both small amounts compared to some others. '''1890 January 29, Wednesday''', Consuelo Lady Mandeville was a guest at the house party around the [[Social Victorians/Santurce Murrieta Wedding 1890-01-29|wedding of Miss Clarita de Murietta and the Duc de Santona]]. She had her eldest son with her, Lord Kimbolton (the 9th Duke of Manchester). Her mother in law, [[Social Victorians/People/Louisa Montagu Cavendish|Louise, Duchess of Manchester]] was also present. '''1890 February 6, Thursday''' '''(shortly before 6 February)''', Lord Mandeville attended a [[Social Victorians/Timeline/1890#1890 February 6, Thursday|boxing match fought by the prize-fighter Pete Jackson]] at the New Pelican Club. '''1890 January 30, Thursday, through at least February 8, Saturday''', Lord Mandeville was among the [[Social Victorians/Timeline/1890#1890 February 8, Saturday|recent arrivals at Brighton]] although apparently after the most notable had already left. Certainly he does not appear to have been at the party the next evening that the Prince of Wales attended. '''1890 February 9, Sunday''', the Prince of Wales came after one of Consuelo's dinner parties:<blockquote>Lady Mandeville, who has been giving a series of small dinners in her house in Cumberland Place, had a dinner on Sunday. The Prince of Wales came in after dinner to meet a small party.<ref>"Society Gossip. (From ''The World''.)." ''Leighton Buzzard Observer and Linslade Gazette'' 11 February 1890, Tuesday: 6 [of 8], Col. 6b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001091%2F18900211&page=6&article=106&stringtohighlight=mandeville+viscount. Print title: ''The Leighton Buzzard Observer'', p. 6. </ref></blockquote>'''1890 February 24, Monday''', Consuelo Lady Mandeville attended [[Social Victorians/Timeline/1890#24 February 1890, Monday|Lilly Langtry's performance as Rosalind in As You Like It at the St. James's Theatre]]. '''1890 February 25, Tuesday''', Consuelo Lady Mandeville attended a [[Social Victorians/Timeline/1890#25 February 1890, Tuesday|party hosted by Mrs. Adair]]. Viscount Mandeville is not listed among those who attended. '''1890 March 4, Wednesday''', Consuelo's brother Fernando Yznaga married New York "beauty and society leader" Miss Mabel Wright.<ref>"Personal." ''American Register'' 22 March 1890, Saturday: 5 [of 8], Col. 5a [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0003338%2F18900322&page=5&article=070&stringtohighlight=mandeville+viscount. Same print title and p.</ref> Presumably at least Consuelo was there? '''1890 March 10, Monday''', the Prince and Princess of Wales gave a [[Social Victorians/Timeline/1890#10 March 1890, Monday10 March 1890, Monday|dance at Marlborough House in honor of their wedding anniversary]]. The Viscountess Mandeville is listed among the guests invited, but the Viscount is not mentioned. '''1890 March 22, Saturday''', the Portsmouth ''Evening News'' expressed outrage about a man with a reputation like Lord Mandeville's becoming 8th Duke of Manchester and joining the House of Lords:<blockquote>While the House of Commons were debating the necessity for a House of Lords, the Duke of Manchester was on his death bed in Naples. There is more in the incident than appears at first sight, for Viscount Mandeville succeeds to the Dukedom, with the attendant rights of presentation to seven livings and the privilege of mutilating or rejecting Bills demanded by the people and passed by their representatives in the Commons. {{Paragraph break}} It will hardly be urged by the moat zealous advocate of the Upper Chamber, as at present constituted, that the new Duke of Manchester, ''nee'' Viscount Mandeville, will bring much dignity, wisdom, or weight to the House of irresponsible legislators. This nobleman has had a merry time. The one sensible thing he did was to marry a charming and accomplished American lady, who, by consenting to share the name of Mandeville has kept its head above water. Viscount Mandeville himself has a weakness for bankruptcy proceedings, rows with cabmen, which music hall ladies come forward to take his part, and the class of events generally which do not approve themselves to the minds of the ordinary Briton. It is possible that Lord Mandeville may now discover that he has sown his wild oats, and may settle down with his beautiful and popular wife to the enjoyment of his 25,000 acres of land and £38,000 a-year. We have not to do with what Lord Mandeville may be. Our simple duty is to point out that it is an outrage on common decency and common sense that a man bearing the reputation of Lord Mandeville should have the right to step into the House of Lords whenever a vote is needed to swell the prejudice or sustain the selfishness that find among the Peers their natural home.<ref>"To-Day." ''Portsmouth Evening News'' 22 March 1890, Saturday: 2 [of 4], Col. 1c [of 6]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000290%2F18900322&page=2&article=001&stringtohighlight=mandeville+viscount. Print title: ''The Evening News'', n.p.</ref></blockquote>The ''Birmingham Daily Mail'' had a similar opinion, though perhaps slightly more optimistic:<blockquote>The Duke of Manchester, who expired last night at Naples, cannot be said to have been much of a public man. He led a quiet, retired life, and the announcement of his death would, if Lord Mandeville were not heir to the title, arouse but little interest. Lord Mandeville is, unfortunately for himself, more widely known than his father was. He developed tastes for gambling, with disastrous financial results, as the details of his bankruptcy made public last year, and more recently, his name has been publicly associated with those of prizefighters and music-hall singers. Altogether, he can hardly be termed a credit to the aristocracy of England, but the higher position to which he will now attain may cause him to alter his ways and try redeem the errors of the past.<ref>"Notes and News." ''Birmingham Mail'' 22 March 1890, Saturday: 2 [of 4], Col. 3a [of 8]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000644%2F18900322&page=2&article=027&stringtohighlight=mandeville+viscount. Print title: ''Birmingham Daily Mail'', n.p.</ref></blockquote>On the same day, Consuelo's brother and new wife were reported to apparently be immigrating to the UK:<blockquote>Among the immigrants, says a London lady correspondent, is a New York belle who has just been married to Mr. Ferdinand Yznaga, brother to Lady Mandeville and of Lady Lister-Kaye. Young Mrs. Yznaga will enter London society under the wing of her sister-in-law, Lady Mandeville, and is expected to make as great a furore as did Mrs. Langtry a few seasons ago. Mr. Yznaga married a sister-in-law of Mr. Vanderbilt, who divorced him two years ago.<ref>"An American Belle." ''Huddersfield and Holmfirth Examiner'' 22 March 1890, Saturday: 6 [of 16], Col. 4a [of 6]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0003869%2F18900322&page=6&article=006&stringtohighlight=mandeville+viscount. Print title: ''The Huddersfield Examiner'', p. 6.</ref></blockquote>'''1890 November 14''', William Angus Drogo Montagu (9th Duke) and Helena Zimmerman married secretly, in London. '''1897 July 2''', the Duke and Duchess of Devonshire ( [[Social Victorians/People/Louisa Montagu Cavendish|Luise Friederike Auguste Gräfin von Alten Montagu Cavendish]] and [[Social Victorians/People/Spencer Compton Cavendish|Spencer Cavendish]]) hosted the [[Social Victorians/1897 Fancy Dress Ball|Duchess of Devonshire's fancy-dress ball]] at Devonshire House. Lord Charles Montagu, likely Charles William Augustus Montagu, attended, as did [[Social Victorians/People/William Angus Drogo Montagu|William Angus Drogo Montagu]], the 9th Duke, who was 20 at the time. But Consuelo, Duchess of Manchester did not attend? Even though she had been so intimate with the Prince of Wales? The 8th Duke, Kim Montagu (Louisa's son), died in 1892. == Demographics == ===Nationality=== *Consuelo Iznaga y Clement was Cuban-American. *Helena Zimmerman was American. *George, William and Alexander Montagu were British. === Residences === * 1890: "The family estates — 27,312 acres, with a nominal rent-roll of £40,000 — were chiefly situated in Huntingdonshire and Armagh."<ref>"Men and Things." (London) ''Echo'' 22 March 1890, Saturday: 1 [of 4], Col. 6b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0004596%2F18900322&page=1&article=010&stringtohighlight=mandeville+viscount. Same print title, n.p.</ref> * In 1890 at the death of the 7th Duke, Kimbolton Castle: <blockquote>The [7th] Duke of Manchester... He was an old-fashioned Tory, and a man of simple tastes, whose chief interests were military and agricultural rather than political. Kimbolton Castle is a magnificent place, and the Duke's horses and troop of yeomanry were always the admiration of the Prince of Wales, the Marquis of Hartington, and many other visitors. Lord Hartington, it may be mentioned, was at Kimbolton when the news came of the  breaking out of the war between France and Germany [1871], he being a member of the Cabinet. The Duke had travelled much as a young man, and was familiar with the Continent, as also with South Africa, of which he was very fond. There is a private chapel at Kimbolton Castle, connected with which is a very extensive library containing some theological and historical volumes of great value. Notwithstanding his somewhat bluff manner the Duke was liked by the tenantry and poor from the kindly interest he took in their concerns. Even the poachers had a good word for his Grace. The feature, however, of the Duke's career was the marked contrast between his pursuits and those of the Duchess. The Duke loved every blade of grass, every tree and flower on his ancestral domain, and cared nothing for London life in its modern developments. Lord Mandeville [the 8th Duke] succeeds to the title, but the estates are heavily mortgaged.<ref>"Death of the Duke of Manchester." ''Pall Mall Gazette'' 22 March 1890, Saturday: 6 [of 8], Col. 2b [of 3]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000098%2F18900322&page=6&article=014&stringtohighlight=mandeville+viscount. Same print title and p. </ref></blockquote> == Family == *Consuelo (María Consuelo) Iznaga y Clement Montagu, Duchess of Manchester (1853 – 20 November 1909), née Doña María Consuelo Iznaga y Clement<ref name=":0" /> *"Kim" (George Victor Drogo) Montagu, 8th Duke of Manchester (17 June 1853 – 18 August 1892)<ref name=":1" /> #William Angus Drogo Montagu, 9th Duke of Manchester (3 March 1877 – 9 February 1947) #Jacqueline Mary Alva Montagu (27 November 1879 – 15 March 1895). #Alice Eleanor Louise Montagu (27 November 1879 – 10 January 1900) *[[Social Victorians/People/William Angus Drogo Montagu|William Angus Drogo Montagu]], 9th Duke of Manchester (3 March 1877 – 9 February 1947)<ref>{{Cite journal|date=2020-10-08|title=William Montagu, 9th Duke of Manchester|url=https://en.wikipedia.org/w/index.php?title=William_Montagu,_9th_Duke_of_Manchester&oldid=982513036|journal=Wikipedia|language=en}}</ref> *Helena Zimmerman Montagu (25 September 1878 – 15 December 1971)<ref>{{Cite journal|date=2020-10-08|title=Helena, Countess of Kintore|url=https://en.wikipedia.org/w/index.php?title=Helena,_Countess_of_Kintore&oldid=982513630|journal=Wikipedia|language=en}}</ref> #Mary Alice Montagu Gregory (26 October 1901 – 9 October 1962) #Alexander George Francis Drogo Montagu, 10th Duke of Manchester (2 October 1902 – 23 November 1977) #Edward Eugene Fernando Montagu (26 July 1906 – 4 May 1954/1956) #Ellen Millicent Louise Montagu Hofer Shairp (5 January 1908 – 2 August 1948) === Relations === The three Iznaga y Clement sisters were prominent in London "Society": *Consuelo (María Consuelo) Iznaga Montagu, Duchess of Manchester (1853 – 20 November 1909) *Emilie Iznaga y Clement () *Natividad (Natica) Iznaga y Clement Lister-Kaye () == Questions and Notes == *In a ''British Newspaper Archive'' search for name=mandeville keyword=#viscount for 18 August 1855–22 March 1890 (September 2026), first did "Publication date oldest first," but Kim was 2 years old when his grandfather died and his father acceded to the dukedom, so on p. 57 of the search results (the page containing 1 January 1856) I switched to "Publication date newest first." Decided it would be more fruitful to work backwards. == Papers, Memoirs and Biographies == * Personal correspondence: in the archive at Chatsworth House (group <code>CS8</code>) * The papers of Louise Cavendish, Duchess of Devonshire DF14 contains correspondence to and from the 7th Duke and Duchess of Manchester. * Archives Hub: https://archiveshub.jisc.ac.uk/ (for records of UK archives, including Northern Ireland, but not the Republic of Ireland) ** Chatsworth House: https://archiveshub.jisc.ac.uk/search/locations/6e07905a-1893-3adb-93fa-6966fcfaf57e ** Louise Cavendish papers: https://archiveshub.jisc.ac.uk/search/archives/7f2209dd-e364-3318-8a5e-62e0533d7a4c ** Devonshire Collection Archives: Family papers: https://www.chatsworth.org/visit-chatsworth/chatsworth-estate/art-archives/access-the-collection/archives-and-library/family-papers-guide/ == Footnotes == {{reflist}} 4kgb0rtw4v83rgr90e501gsht3giwxj 0 264898 2844864 2687582 2026-11-08T12:13:16Z ~2026-59322-88 3114003 /* Derby Day at Epsom Downs */ Correction 2844864 wikitext text/x-wiki =Derby Day at Epsom Downs= ==Logistics== The Epsom Derby has been run regularly since 1780:<blockquote>Initially, the Derby was run on a Thursday in late May or early June, depending on when Easter occurred. In 1838 the race was moved to a Wednesday to fit in with the railways' timetables, but still followed the moveable feast of Easter.<ref name=":0">{{Cite journal|date=2024-08-30|title=Epsom Derby|url=https://en.wikipedia.org/wiki/Epsom_Derby|journal=Wikipedia|language=en}} https://en.wikipedia.org/wiki/Epsom_Derby.</ref></blockquote>It was run generally on Wednesdays throughout much of the 19th and 20th centuries, being changed to Saturday in 1994.<ref name=":0" /> The racecourse is near the town Epsom and the races were originally sponsored by the [[Social Victorians/People/Derby|Earl of Derby]].<ref name=":0" /> Derby Day was the one of several days of horse racing, the one most carnival-like socially speaking, and one of the most prestigious races in the UK. The racing at Epsom Downs was actually a number of races, with Derby Day being the most important. In the late 19th century, the racing began on Tuesday and lasted through Friday. Also, by the end of the century, races occurred on other days of the year and attracted "the fashionable people."<ref>"Hints for Ladies. Fashion at Derby Races." ''Derby Mercury'' 24 November 1897, Wednesday: 6 [of 8], Col. 5a [of 7]. British Newspaper Archive <nowiki>https://www.britishnewspaperarchive.co.uk/viewer/bl/0000052/18971124/050/0006</nowiki>.</ref> Oak Day was the day after Derby Day at Epsom Downs. ==Dates of Derby Day== * Wednesday, 24 May 1871, [[Social Victorians/People/Rothschild Family|Baron Rothschild]]'s Favonius won. The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] attended. * Wednesday, 29 May 1872 * Wednesday, 28 May 1873 * Wednesday, 3 June 1874 * Wednesday, 26 May 1875 * Wednesday, 31 May 1876 * Wednesday, 30 May 1877 * Wednesday, 5 June 1878 * Wednesday, 28 May 1879 * Wednesday, 26 May 1880 * Wednesday, 1 June 1881 * Wednesday, 24 May 1882 * Wednesday, 23 May 1883 * Wednesday, 28 May 1884 * Wednesday, 3 June 1885 * Wednesday, 26 May 1886 * Wednesday, 25 May 1887 * Wednesday, 30 May 1888 * Wednesday, 5 June 1889 * Wednesday, 4 June 1890 * Wednesday, 27 May 1891 * Wednesday, 31 May 1893 * Wednesday, 6 June 1894 * Wednesday, 29 May 1895 * Wednesday, 3 June 1896 * Wednesday, 2 June 1897 * Wednesday, 25 May 1898 * Wednesday, 31 May 1899 * Wednesday, 30 May 1900 ==Related Events== * The night after the running of the Derby at Epsom Downs (although not the one on this list?), [[Social Victorians/People/Louisa Montagu Cavendish | Luisa Friederike Auguste Montagu Cavendish]], Duchess of Manchester and, after 16 August 1892, Duchess of Devonshire, hosted her famous [[Social Victorians/1897 Fancy Dress Ball |1897 fancy-dress ball]]. ===Who Was Present=== # The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] often attended the Epsom Down races accompanied by a large retinue of friends. ==Questions and Notes== # ==Bibliography== * Murphy, Sophia. The Duchess of Devonshire's Ball. London: Sidgwick & Kackson, 1984. == References == 2q9sh9quieugvzmbfp95o71nsuukfzr 2844865 2844864 2026-11-08T13:13:14Z ~2026-59322-88 3114003 /* Derby Day at Epsom Downs */ Additional information 2844865 wikitext text/x-wiki =Derby Day at Epsom Downs= ==Logistics== The Epsom Derby has been run regularly since 1780:<blockquote>Initially, the Derby was run on a Thursday in late May or early June, depending on when Easter occurred. In 1838 the race was moved to a Wednesday to fit in with the railways' timetables, but still followed the moveable feast of Easter.<ref name=":0">{{Cite journal|date=2024-08-30|title=Epsom Derby|url=https://en.wikipedia.org/wiki/Epsom_Derby|journal=Wikipedia|language=en}} https://en.wikipedia.org/wiki/Epsom_Derby.</ref></blockquote>It was run generally on Wednesdays throughout much of the 19th and 20th centuries, being changed to Saturday in 1994.<ref name=":0" /> The racecourse is near the Surrey town of Epsom and the races were originally sponsored by the [[Social Victorians/People/Derby|Earl of Derby]].<ref name=":0" /> Derby Day was the one of several days of horse racing, the one most carnival-like socially speaking, and one of the most prestigious races in the UK. The racing at Epsom Downs was actually a number of races, with Derby Day being the most important. In the late 19th century, the racing began on Tuesday and lasted through Friday. Also, by the end of the century, races occurred on other days of the year and attracted "the fashionable people."<ref>"Hints for Ladies. Fashion at Derby Races." ''Derby Mercury'' 24 November 1897, Wednesday: 6 [of 8], Col. 5a [of 7]. British Newspaper Archive <nowiki>https://www.britishnewspaperarchive.co.uk/viewer/bl/0000052/18971124/050/0006</nowiki>.</ref> Oak Day was the day after Derby Day at Epsom Downs. ==Dates of Derby Day== * Wednesday, 24 May 1871, [[Social Victorians/People/Rothschild Family|Baron Rothschild]]'s Favonius won. The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] attended. * Wednesday, 29 May 1872 * Wednesday, 28 May 1873 * Wednesday, 3 June 1874 * Wednesday, 26 May 1875 * Wednesday, 31 May 1876 * Wednesday, 30 May 1877 * Wednesday, 5 June 1878 * Wednesday, 28 May 1879 * Wednesday, 26 May 1880 * Wednesday, 1 June 1881 * Wednesday, 24 May 1882 * Wednesday, 23 May 1883 * Wednesday, 28 May 1884 * Wednesday, 3 June 1885 * Wednesday, 26 May 1886 * Wednesday, 25 May 1887 * Wednesday, 30 May 1888 * Wednesday, 5 June 1889 * Wednesday, 4 June 1890 * Wednesday, 27 May 1891 * Wednesday, 31 May 1893 * Wednesday, 6 June 1894 * Wednesday, 29 May 1895 * Wednesday, 3 June 1896 * Wednesday, 2 June 1897 * Wednesday, 25 May 1898 * Wednesday, 31 May 1899 * Wednesday, 30 May 1900 ==Related Events== * The night after the running of the Derby at Epsom Downs (although not the one on this list?), [[Social Victorians/People/Louisa Montagu Cavendish | Luisa Friederike Auguste Montagu Cavendish]], Duchess of Manchester and, after 16 August 1892, Duchess of Devonshire, hosted her famous [[Social Victorians/1897 Fancy Dress Ball |1897 fancy-dress ball]]. ===Who Was Present=== # The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] often attended the Epsom Down races accompanied by a large retinue of friends. ==Questions and Notes== # ==Bibliography== * Murphy, Sophia. The Duchess of Devonshire's Ball. London: Sidgwick & Kackson, 1984. == References == gs4njpq40ifc26fiv5zpgy2vdrbrter 2844866 2844865 2026-11-08T13:15:30Z ~2026-59322-88 3114003 /* Derby Day at Epsom Downs */ Correction of date 2844866 wikitext text/x-wiki =Derby Day at Epsom Downs= ==Logistics== The Epsom Derby has been run regularly since 1780:<blockquote>Initially, the Derby was run on a Thursday in late May or early June, depending on when Easter occurred. In 1838 the race was moved to a Wednesday to fit in with the railways' timetables, but still followed the moveable feast of Easter.<ref name=":0">{{Cite journal|date=2024-08-30|title=Epsom Derby|url=https://en.wikipedia.org/wiki/Epsom_Derby|journal=Wikipedia|language=en}} https://en.wikipedia.org/wiki/Epsom_Derby.</ref></blockquote>It was run generally on Wednesdays throughout much of the 19th and 20th centuries, being changed to Saturday in 1995.<ref name=":0" /> The racecourse is near the Surrey town of Epsom and the races were originally sponsored by the [[Social Victorians/People/Derby|Earl of Derby]].<ref name=":0" /> Derby Day was the one of several days of horse racing, the one most carnival-like socially speaking, and one of the most prestigious races in the UK. The racing at Epsom Downs was actually a number of races, with Derby Day being the most important. In the late 19th century, the racing began on Tuesday and lasted through Friday. Also, by the end of the century, races occurred on other days of the year and attracted "the fashionable people."<ref>"Hints for Ladies. Fashion at Derby Races." ''Derby Mercury'' 24 November 1897, Wednesday: 6 [of 8], Col. 5a [of 7]. British Newspaper Archive <nowiki>https://www.britishnewspaperarchive.co.uk/viewer/bl/0000052/18971124/050/0006</nowiki>.</ref> Oak Day was the day after Derby Day at Epsom Downs. ==Dates of Derby Day== * Wednesday, 24 May 1871, [[Social Victorians/People/Rothschild Family|Baron Rothschild]]'s Favonius won. The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] attended. * Wednesday, 29 May 1872 * Wednesday, 28 May 1873 * Wednesday, 3 June 1874 * Wednesday, 26 May 1875 * Wednesday, 31 May 1876 * Wednesday, 30 May 1877 * Wednesday, 5 June 1878 * Wednesday, 28 May 1879 * Wednesday, 26 May 1880 * Wednesday, 1 June 1881 * Wednesday, 24 May 1882 * Wednesday, 23 May 1883 * Wednesday, 28 May 1884 * Wednesday, 3 June 1885 * Wednesday, 26 May 1886 * Wednesday, 25 May 1887 * Wednesday, 30 May 1888 * Wednesday, 5 June 1889 * Wednesday, 4 June 1890 * Wednesday, 27 May 1891 * Wednesday, 31 May 1893 * Wednesday, 6 June 1894 * Wednesday, 29 May 1895 * Wednesday, 3 June 1896 * Wednesday, 2 June 1897 * Wednesday, 25 May 1898 * Wednesday, 31 May 1899 * Wednesday, 30 May 1900 ==Related Events== * The night after the running of the Derby at Epsom Downs (although not the one on this list?), [[Social Victorians/People/Louisa Montagu Cavendish | Luisa Friederike Auguste Montagu Cavendish]], Duchess of Manchester and, after 16 August 1892, Duchess of Devonshire, hosted her famous [[Social Victorians/1897 Fancy Dress Ball |1897 fancy-dress ball]]. ===Who Was Present=== # The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] often attended the Epsom Down races accompanied by a large retinue of friends. ==Questions and Notes== # ==Bibliography== * Murphy, Sophia. The Duchess of Devonshire's Ball. London: Sidgwick & Kackson, 1984. == References == jwp3mggyfzoa7ht2vj3pwdhuz74qzo0 2844867 2844866 2026-11-08T13:16:00Z ~2026-59322-88 3114003 /* Derby Day at Epsom Downs */ 2844867 wikitext text/x-wiki =Derby Day at Epsom Downs= ==Logistics== The Epsom Derby has been run regularly since 1780:<blockquote>Initially, the Derby was run on a Thursday in late May or early June, depending on when Easter occurred. In 1838 the race was moved to a Wednesday to fit in with the railways' timetables, but still followed the moveable feast of Easter.<ref name=":0">{{Cite journal|date=2024-08-30|title=Epsom Derby|url=https://en.wikipedia.org/wiki/Epsom_Derby|journal=Wikipedia|language=en}} https://en.wikipedia.org/wiki/Epsom_Derby.</ref></blockquote>It was run generally on Wednesdays throughout much of the 19th and 20th centuries, being changed to Saturdays in 1995.<ref name=":0" /> The racecourse is near the Surrey town of Epsom and the races were originally sponsored by the [[Social Victorians/People/Derby|Earl of Derby]].<ref name=":0" /> Derby Day was the one of several days of horse racing, the one most carnival-like socially speaking, and one of the most prestigious races in the UK. The racing at Epsom Downs was actually a number of races, with Derby Day being the most important. In the late 19th century, the racing began on Tuesday and lasted through Friday. Also, by the end of the century, races occurred on other days of the year and attracted "the fashionable people."<ref>"Hints for Ladies. Fashion at Derby Races." ''Derby Mercury'' 24 November 1897, Wednesday: 6 [of 8], Col. 5a [of 7]. British Newspaper Archive <nowiki>https://www.britishnewspaperarchive.co.uk/viewer/bl/0000052/18971124/050/0006</nowiki>.</ref> Oak Day was the day after Derby Day at Epsom Downs. ==Dates of Derby Day== * Wednesday, 24 May 1871, [[Social Victorians/People/Rothschild Family|Baron Rothschild]]'s Favonius won. The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] attended. * Wednesday, 29 May 1872 * Wednesday, 28 May 1873 * Wednesday, 3 June 1874 * Wednesday, 26 May 1875 * Wednesday, 31 May 1876 * Wednesday, 30 May 1877 * Wednesday, 5 June 1878 * Wednesday, 28 May 1879 * Wednesday, 26 May 1880 * Wednesday, 1 June 1881 * Wednesday, 24 May 1882 * Wednesday, 23 May 1883 * Wednesday, 28 May 1884 * Wednesday, 3 June 1885 * Wednesday, 26 May 1886 * Wednesday, 25 May 1887 * Wednesday, 30 May 1888 * Wednesday, 5 June 1889 * Wednesday, 4 June 1890 * Wednesday, 27 May 1891 * Wednesday, 31 May 1893 * Wednesday, 6 June 1894 * Wednesday, 29 May 1895 * Wednesday, 3 June 1896 * Wednesday, 2 June 1897 * Wednesday, 25 May 1898 * Wednesday, 31 May 1899 * Wednesday, 30 May 1900 ==Related Events== * The night after the running of the Derby at Epsom Downs (although not the one on this list?), [[Social Victorians/People/Louisa Montagu Cavendish | Luisa Friederike Auguste Montagu Cavendish]], Duchess of Manchester and, after 16 August 1892, Duchess of Devonshire, hosted her famous [[Social Victorians/1897 Fancy Dress Ball |1897 fancy-dress ball]]. ===Who Was Present=== # The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] often attended the Epsom Down races accompanied by a large retinue of friends. ==Questions and Notes== # ==Bibliography== * Murphy, Sophia. The Duchess of Devonshire's Ball. London: Sidgwick & Kackson, 1984. == References == oar7zx9iqsf41t8koo6aaer73v4e1d4 2844868 2844867 2026-11-08T13:16:37Z ~2026-59322-88 3114003 /* Derby Day at Epsom Downs */ Correction 2844868 wikitext text/x-wiki =Derby Day at Epsom Downs= ==Logistics== The Epsom Derby has been run regularly since 1780:<blockquote>Initially, the Derby was run on a Thursday in late May or early June, depending on when Easter occurred. In 1838 the race was moved to a Wednesday to fit in with the railways' timetables, but still followed the moveable feast of Easter.<ref name=":0">{{Cite journal|date=2024-08-30|title=Epsom Derby|url=https://en.wikipedia.org/wiki/Epsom_Derby|journal=Wikipedia|language=en}} https://en.wikipedia.org/wiki/Epsom_Derby.</ref></blockquote>It was run generally on Wednesdays throughout much of the 19th and 20th centuries, being changed to Saturdays in 1995.<ref name=":0" /> The racecourse is near the Surrey town of Epsom and the races were originally sponsored by the [[Social Victorians/People/Derby|Earl of Derby]].<ref name=":0" /> Derby Day was the one of several days of horse racing, the one most carnival-like socially speaking, and one of the most prestigious races in the UK. The racing at Epsom Downs was actually a number of races, with Derby Day being the most important. In the late 19th century, the racing began on Tuesday and lasted through Friday. Also, by the end of the century, races occurred on other days of the year and attracted "the fashionable people."<ref>"Hints for Ladies. Fashion at Derby Races." ''Derby Mercury'' 24 November 1897, Wednesday: 6 [of 8], Col. 5a [of 7]. British Newspaper Archive <nowiki>https://www.britishnewspaperarchive.co.uk/viewer/bl/0000052/18971124/050/0006</nowiki>.</ref> Oaks Day was the day after Derby Day at Epsom Downs. ==Dates of Derby Day== * Wednesday, 24 May 1871, [[Social Victorians/People/Rothschild Family|Baron Rothschild]]'s Favonius won. The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] attended. * Wednesday, 29 May 1872 * Wednesday, 28 May 1873 * Wednesday, 3 June 1874 * Wednesday, 26 May 1875 * Wednesday, 31 May 1876 * Wednesday, 30 May 1877 * Wednesday, 5 June 1878 * Wednesday, 28 May 1879 * Wednesday, 26 May 1880 * Wednesday, 1 June 1881 * Wednesday, 24 May 1882 * Wednesday, 23 May 1883 * Wednesday, 28 May 1884 * Wednesday, 3 June 1885 * Wednesday, 26 May 1886 * Wednesday, 25 May 1887 * Wednesday, 30 May 1888 * Wednesday, 5 June 1889 * Wednesday, 4 June 1890 * Wednesday, 27 May 1891 * Wednesday, 31 May 1893 * Wednesday, 6 June 1894 * Wednesday, 29 May 1895 * Wednesday, 3 June 1896 * Wednesday, 2 June 1897 * Wednesday, 25 May 1898 * Wednesday, 31 May 1899 * Wednesday, 30 May 1900 ==Related Events== * The night after the running of the Derby at Epsom Downs (although not the one on this list?), [[Social Victorians/People/Louisa Montagu Cavendish | Luisa Friederike Auguste Montagu Cavendish]], Duchess of Manchester and, after 16 August 1892, Duchess of Devonshire, hosted her famous [[Social Victorians/1897 Fancy Dress Ball |1897 fancy-dress ball]]. ===Who Was Present=== # The [[Social Victorians/People/Albert Edward, Prince of Wales |Prince of Wales]] often attended the Epsom Down races accompanied by a large retinue of friends. ==Questions and Notes== # ==Bibliography== * Murphy, Sophia. The Duchess of Devonshire's Ball. London: Sidgwick & Kackson, 1984. == References == njla0diq95bxluxa6qzspcljv95uwz2 0 264910 2844897 2835394 2026-11-08T21:56:35Z Jtneill 10242 /* References */ Alderfer, C. P. (1969). An empirical test of a new theory of human needs. ''Organizational Behavior & Human Performance'', ''4''(2), 142–175. https://doi.org/10.1016/0030-5073(69)90004-X 2844897 wikitext text/x-wiki {{Motivation and emotion/Tutorials|Tutorial 4: Psychological needs|fourth}} {{Motivation and emotion/Tutorials/Complete2}} <!-- {{Motivation and emotion/Tutorials/Complete2}} --> <!-- {{Motivation and emotion/Tutorials/In development}} --> ==Overview== This tutorial facilitates interactive discussion about two aspects of [[self-determination theory]]: # basic psychological needs # taxonomy of motivation (intrinsic-extrinsic motivation) ==Needs== Brainstorm and discuss: {{collapse box|'''What are needs?'''|Needs are ''requirements'' (essential) for surviving (biological needs) and thriving (psychological needs).}} {{collapse box|'''How do needs differ from desires, wants, likes etc.?'''|Needs are ''essential'' for survival (e.g., warmth, transport) and well-being whereas desires, wants, likes etc. are motivations for ''non-essential'' stimuli (e.g., an umbrella in the rain, a new car).}} {{collapse box|'''What types of needs are there?'''|'''2-factor''': deficit-based (biological) needs (e.g., thirst, hunger, sleep) and growth-based (psychological) needs (e.g., autonomy, competence, relatedness).<br>'''3-factor''': The Alderfer ERG theory refers to existence, relatedness, and growth needs.<br>'''5-factor''': Maslow's hierarchy of needs has five needs: Physiological, Safety, Belonging & love, Esteem, Self-actualisation}} {{collapse box|'''What are the basic psychological needs?'''|According to self-determination theory:<br>autonomy, competence, and relatedness}} ==Taxonomy of motivation== Discuss: {{collapse box|'''What characterises [[extrinsic motivation]]? Examples?'''| * External (environmental) reasons for behaving * Caused by carrots (incentives and rewards e.g., praise) or sticks (threats and punishments e.g., insults).}} {{collapse box|'''What characterises [[intrinsic motivation]]? Examples?'''| * Internal reasons for behaving * Involves volition (i.e., ''I want to'') and enjoyment (e.g., hobbies) * External influences are absent.}} {{collapse box|'''Advantages of the I-E motivation distinction?'''| * Breaks motivation down into types * Simple and easy to understand * Helps with research designs}} {{collapse box|'''Disadvantages of the I-E motivation distinction?'''| * A dichotomous distinction is overly simplistic * Motivational sources are often complex and dynamic, involving aspects of both intrinsic and extrinsic motivation}} {{collapse box|'''Types of motivation described by Deci and Ryan (2000)'''| * Amotivation * Extrinsic motivation ** External regulation ** Introjection ** Identification ** Integration * Intrinsic motivation }} <!-- Handout a [https://drive.google.com/file/d/0B2N4zSp4hmN9WHEwSmoyUWhOZm8/view?usp=sharing blanked version of Deci and Ryan's taxonomy] and facilitate the class to define, discuss, and generate examples for each of the components:--> == Quiz: Identify the type of motivation == This 12-item quiz tests your knowledge of Deci and Ryan's taxonomy of motivation. [[/Quiz|Go to quiz]]. Alternative (advenced) exercise: What strategies can motivate exercise behaviours? * Brainstorm ways of motivating healthy exercise behaviours. * Allocate each of these strategies along the taxonomy of motivation, including amotivation, the four types of extrinsic motivation, and intrinsic motivation. '''Table 1'''. What Might Someone With Each of These Six Types of Motivation Say about Their Reasons for Exercising? {| class="wikitable" style="margin: auto;" ! Type !! Example reason |- | '''Amotivation''' | " ......... ? ......... " |- | '''External regulation''' | " ......... ? ......... " |- | '''Introjection''' | " ......... ? ......... " |- | '''Identification''' | " ......... ? ......... " |- | '''Integration''' | " ......... ? ......... " |- | '''Intrinsic motivation''' | " ......... ? ......... " |} For examples, see Table 2. ==Answers== '''Table 2'''. Examples of Reasons to Engage in Healthy Exercise Based on the Taxonomy of Motivation (Deci & Ryan, 2000) {| class="wikitable" style="margin: auto;" ! Type !! Example reason |- | '''Amotivation''' | "I don't see any point in exercising because it doesn't make a difference." |- | '''External regulation''' | "My doctor told me I have to exercise." |- | '''Introjection''' | "I feel guilty when I don't exercise." |- | '''Identification''' | "Being fit is important to me." |- | '''Integration''' | "Taking care of my body is part of who I am." |- | '''Intrinsic motivation''' | "I exercise because I genuinely enjoy being active." |} ==Topic development feedback== * '''Check your feedback and marks''' ** Check the marks on [[Motivation and emotion/Assessment/Topic|UCLearn]] ** For written feedback, consult: *** [[Motivation and emotion/Assessment/Topic/Feedback|Topic development - General feedback]] *** Topic-specific feedback on the topic's [[Motivation and emotion/Assessment/Topic|discussion (talk) page]] for written feedback ** Follow up if you do not understand the feedback * '''Align the topic structure''' ** Ensure clear alignments across '''title/sub-title → focus questions → headings''' ** Make sure each heading directly addresses the topic and contributes to answering the focus questions ** Avoid too much general background information: '''focus directly on the topic and cut to the chase''' * '''Balance theory and research''' ** Balance coverage of '''theory and research''', ideally integrating them rather than treating them as separate sections ** Identify and use the '''best psychological science on the topic''', particularly systematic reviews and/or meta-analyses ** Avoid relying too heavily on theory and too little on relevant empirical research * '''Embed links to related information''' ** As a learning feature, add relevant links on first mention of key words to: *** Other [[Motivation and emotion/Book|book chapters]] *** [[Wikipedia]] articles *** Other useful sources of information where appropriate * '''Acknowledge generative AI use''' ** Acknowledge use of generative AI in '''edit summaries''' by including a '''shared link to the ChatGPT conversation''' ** Follow the [[Motivation and emotion/Assessment/Using generative AI|using generative AI guidelines]] for academic honesty and transparency ===Messy middle=== We are now in the "messy middle" of the [[Motivation and emotion/Assessment/Chapter|book chapter]] development: * '''Motivational pattern''' (consistent with motivational science about the trajectory of motivation) ** Strong at '''start''' (excitement, newness) ** Strong at '''end''' (deadline pressure, completion goals) ** Dips in '''middle''' (novelty fades, finish feels long, distractions increase) * '''Strategies for the middle''' ** Make '''small, regular edits''' → steady progress ** Use '''scaffolding''' → build on [[Motivation and emotion/Assessment/Topic|topic development]] feedback and work towwards [[Motivation and emotion/Assessment/Chapter|chapter guidelines]] ** Seek clarification; follow up if unsure * '''Key idea''' ** Keep '''momentum''' alive in the “messy middle”—in this case, by doing small edits regularly to move from Topic Development → Book Chapter ==Recording== * [https://au-lti.bbcollab.com/recording/56e88f2f9a5a4977972c3adcf0b116fb Tutorial 4] (2026)<!-- * [https://au-lti.bbcollab.com/recording/fecbd3c2b9c94ee8bf7aaf6730226a53 Tutorial 4] (2025) * [https://au-lti.bbcollab.com/recording/9717613592cf458099da1b8e021fe13f Tutorial 4] (2024) * [https://au-lti.bbcollab.com/recording/5a95256f932d4e228992199adcb6c094 Tutorial 4] (2023) * [https://au-lti.bbcollab.com/recording/8eeaa7d6c18c4efbafc2c28984bfbaca Tutorial 4] (2022) * [https://au-lti.bbcollab.com/recording/ee193c24a6414276b3d47acba500d433 Tutorial 4] (2021) --> ==See also== * [[/Instructor notes/]] ;Additional tutorial material * [[/Example of self-determination theory: Child cleaning teeth/|Example of SDT: Child cleaning teeth]] * [[../Needs/Implicit motives/|Implicit motives]] * [[../Needs/Models which provide organisation of needs/|Models which organise needs]] * [[/Self-determination theory/]] <!-- ;Book chapters --> <!-- ;Wikipedia --> ; Lecture * [[Motivation and emotion/Lectures/Extrinsic motivation and psychological needs|Extrinsic motivation and psychological needs]] ;Tutorials * [[{{#titleparts:{{PAGENAME}}|2}}/Physiological needs|Physiological needs]] (Previous tutorial) * [[Motivation and emotion/Tutorials/Functionalist theory and self-tracking|Functionalist theory and self-tracking]] (Next tutorial) <!-- ;Admin * [[/Instructor notes/]] --> ==References== {{Hanging indent|1= Alderfer, C. P. (1969). An empirical test of a new theory of human needs. ''Organizational Behavior & Human Performance'', ''4''(2), 142–175. https://doi.org/10.1016/0030-5073(69)90004-X Deci, R. M., & Ryan, E. L. (2000). Intrinsic and extrinsic motivations: Classic definitions and new directions. ''Contemporary Educational Psychology'', ''25''(1), 54–67. https://doi.org/10.1006/ceps.1999.1020 [https://www.sciencedirect.com/science/article/pii/S0361476X99910202/pdf?md5=b9e2589a068cf7f9529c1bff165ddd55&pid=1-s2.0-S0361476X99910202-main.pdf PDF]}} ==External links== * [http://www.youtube.com/watch?v=VGrcets0E6I Promoting motivation, health, and excellence] (Ed Deci, 2012, TEDx, YouTube 14:05 mins) * [https://selfdeterminationtheory.org/ Self-determination theory] (selfdeterminationtheory.org) <noinclude>{{Motivation and emotion/Tutorials/Navigation}}</noinclude> [[Category:Motivation and emotion/Tutorials/Psychological needs]] amthxeqgohlwusgdifhztjy7d6zol0y 0 269370 2844881 2844733 2026-11-08T17:06:26Z James500 297601 /* Japan */ Add 2844881 wikitext text/x-wiki {{Bibliography}} See also [[Universal Bibliography/Geography|Geography]]. See [[w:Category:Bibliographies of countries or regions]] and [[w:Category:Works about countries]]. This part of the [[Universal Bibliography]] is a bibliography of countries (including former countries). ==Countries== *Bateman and Egan (eds). The Encyclopedia of World Geography: A Country by Country Guide. 1993. Revised 1997. *Peter Stalker. Handbook of the World. 2000. A Guide to Countries of the World. (Oxford Guide to Countries of the World. 2nd Ed: 2004, 2nd Revised Ed: 2007 [https://books.google.co.uk/books?id=GtztAAAAMAAJ], 3rd Ed: 2010 [https://books.google.co.uk/books?id=gvKvfxkbZ1AC&pg=PP1#v=onepage&q&f=false] *Countries of the World and Their Leaders Yearbook. Gale. [https://books.google.co.uk/books?id=5etKAAAAYAAJ] [https://books.google.co.uk/books?id=p41OAAAAIAAJ] *Hutchinson Guide to Countries of the World [https://books.google.co.uk/books?id=GgpjUe4kN_IC] *The World Guide: Global Reference, Country by Country. 11th Ed: 2007 [https://books.google.co.uk/books?id=EoWoLgAACAAJ] *Spence. The World Today: A Nation-by-Nation Guide. Cassell. 1994. 1999. [https://books.google.com/books?id=Ub8qOQAACAAJ] *Worldmark Encyclopedia of the Nations [https://books.google.co.uk/books?id=I0oYAQAAMAAJ] *Kurian. Encyclopedia of the World's Nations. Facts on File. Reviews: [https://books.google.co.uk/books?id=Y1EnAQAAIAAJ] [https://books.google.co.uk/books?id=lz0RAQAAMAAJ] *Michael O'Mara. Facts about the World's Nations. 1999. [https://books.google.co.uk/books?id=mygYAAAAIAAJ] *Status of the World's Nations. 1965 [https://books.google.co.uk/books?id=sftEyRbAXMUC&pg=PP1#v=onepage&q&f=false]. 1973 [https://books.google.co.uk/books?id=kw2U_Cg2gKYC&pg=PP3#v=onepage&q&f=false]. *[[s:Author:John Alexander Hammerton|Hammerton, John Alexander]] (ed). Countries of the World. Published at the Fleetway House. 6 vols. [https://books.google.co.uk/books?id=e6IaAQAAMAAJ] [https://books.google.co.uk/books?id=K5oaAQAAMAAJ] *[[s:Author:Robert Brown (1842-1895)|Brown, Robert]]. The Countries of the World. [https://books.google.co.uk/books?id=nO0DAAAAQAAJ&pg=PP13#v=onepage&q&f=false] *A Morely Dell. The Countries of the World. (Harrap's New Geographical Series). 1932. (School certificate). Reviews: [https://books.google.co.uk/books?id=oSS9PB_Jf7AC] [https://books.google.co.uk/books?id=BicVAAAAIAAJ] [https://books.google.co.uk/books?id=5qBOAAAAIAAJ] [https://books.google.co.uk/books?id=YbwcAQAAIAAJ] [https://books.google.co.uk/books?id=sc1AAAAAIAAJ] General series: *National Geographic Countries of the World [https://books.google.co.uk/books?id=IT2wfzVIPykC] *Countries of the World. Evans Brothers. (GCSE) [https://books.google.co.uk/books?id=a3sZvWc7E1EC&pg=PA1#v=onepage&q&f=false] *One Europe. Longman. [https://search.worldcat.org/en/title/west-germany-adapted-by-lj-russon-from-the-original-german-by-sylvia-lof-ingrid-mallberg-dietrich-rosenthal/oclc/561591761] *Collier's Nations of the World. The Nations of the World: An Historical Series. [https://books.google.co.uk/books?id=VJY-AAAAYAAJ&pg=PP8#v=onepage&q&f=false] *Collier's History of Nations. The History of Nations. [https://books.google.co.uk/books?id=fmSUfTY5E80C] *The Story of the Nations. T Fisher Unwin. *The World and Its Peoples. (The Illustrated Library of the World and Its Peoples). Greystone Press, New York. *World and Its Peoples. Marshall Cavendish. [https://books.google.co.uk/books?id=oms5xjI7ba0C&pg=PA141#v=onepage&q&f=false] ==England== ===Counties=== See [[s:Portal:Counties]] * Harrison, "County Bibliography" (1886) 3 Library Chronicle [https://books.google.co.uk/books?id=Wz9FAAAAYAAJ&pg=PA49#v=onepage&q&f=false 49] General series *Victoria County History *Oxford County Histories *Pinnock's County Histories *Shire County Guides. Shire Publications. *Cambridge County Geographies *Pike's New Century Series *[[s:Page:County Churches of Cornwall.djvu/6|County Churches]]. G Allen. Avon *Moore. Avon Local History Handbook. Phillimore. 1979. [https://books.google.co.uk/books?id=h0kjAAAAMAAJ] Bibliography, p 102 Bedfordshire *Conisbee, Lewis Ralph. A Bedfordshire Bibliography. Bedfordshire Historical Record Society. Bedford. 1962. Supplements 1967, 1971, 1978. Third supplement by Threadgill. Review: 6 Archives 52 [https://books.google.co.uk/books?id=oOMZAAAAYAAJ]. See also [https://books.google.co.uk/books?id=MjspAAAAYAAJ] [https://books.google.co.uk/books?id=PejgAAAAMAAJ] *Godber. History of Bedfordshire. 1969. 1984. [https://books.google.co.uk/books?id=jdvwPQAACAAJ] *Pinnock. The History and Topography of Bedfordshire [https://books.google.co.uk/books?id=9bJYAAAAcAAJ&pg=PR3#v=onepage&q&f=false] *Parry. Select Illustrations, Historical and Topographical, of Bedfordshire [https://books.google.co.uk/books?id=UTUJAAAAQAAJ&pg=PP7#v=onepage&q&f=false] *Blyth. The History of Bedford and Visitor's Guide. 1873 [https://books.google.co.uk/books?id=IuIGAAAAQAAJ&pg=PP5#v=onepage&q&f=false] *Cambridge County Geographies [https://books.google.co.uk/books?id=kTc8AAAAIAAJ&pg=PP1#v=onepage&q&f=false] Buckinghamshire *Reed. A History of Buckinghamshire. 1993 [https://books.google.co.uk/books?id=BtkWAQAAIAAJ] Cambridgeshire *Carter. History of the County of Cambridge [https://books.google.co.uk/books?id=jXpbAAAAQAAJ&pg=PR3#v=onepage&q&f=false] *Babington. Ancient Cambridgeshire [https://books.google.co.uk/books?id=DPrCAwAAQBAJ&pg=PP1#v=onepage&q&f=false] Devon *Ravenhill and Rowe. Devon Maps and Map-makers [https://books.google.co.uk/books?id=tjf2yAEACAAJ] *Wright. A Plea for a Devonshire Bibliography. 1885 [https://books.google.co.uk/books?id=8ZUDAAAAQAAJ] Derbyshire *Woore. A Catalogue of Local Maps of Derbyshire, C.1528-1800. 2012. [https://books.google.co.uk/books?id=oWmCMwEACAAJ] *O'Neal. A Bibliography of Derbyshire Lead Mining. 1961 Essex *Cunnington. Catalogue of Books, Maps and Manuscripts, relating to or connected with the County of Essex. 1902 [https://books.google.co.uk/books?id=oIcqpibGE4MC] *"The Bibliography of Essex" (1882) 1 Antiquarian Magazine & Bibliographer [https://books.google.co.uk/books?id=dEkEAAAAQAAJ&pg=PA72#v=onepage&q&f=false 72]. See also [https://books.google.co.uk/books?id=dEkEAAAAQAAJ&pg=PA283#v=onepage&q&f=false p 283]. *"The Bibliography of Essex" (1891) 5 The Essex Naturalist 30 [https://books.google.co.uk/books?id=iIo1AQAAMAAJ] *Moon. Essex Literature. 1900. Review: 61 Literary World 438 [https://books.google.co.uk/books?id=2T0ZAAAAYAAJ] See also [https://books.google.co.uk/books?id=1Y4UAQAAIAAJ] [https://books.google.co.uk/books?id=C_pEAAAAMAAJ] *Fenn and Lowery, "An Essex Bibliography", Journal of the South West Essex Technical College, vols 2 & 3 *Victoria County History bibliography. 1959 [https://books.google.co.uk/books?id=F2EJAQAAIAAJ] *O'Leary, John Gerard. A Supplement to the Essex Bibliography. Dagenham. 1962. *A Bibliography of Essex Archaeology & History *Essex and Dagenham: A Catalogue of Books, Pamphlets and Maps. Dagenham. 1961 *Essex Archaeology and History: The Transactions of the Essex Society for Archaeological and History [https://books.google.co.uk/books?id=CtFAAAAAYAAJ] *Essex Naturalist: Being the Journal of the Essex Field Club *Wright. The History and Topography of the County of Essex [https://books.google.co.uk/books?id=SgQVAAAAQAAJ&pg=PP9#v=onepage&q&f=false] *Ogborne, The History of Essex [https://books.google.co.uk/books?id=IeVSAAAAcAAJ&pg=PP5#v=onepage&q&f=false] *Suckling. Memorials of the Antiquities and Architecture, Family History and Heraldry of the County of Essex [https://books.google.co.uk/books?id=bcw_AAAAcAAJ&pg=PP7#v=onepage&q&f=false] *Hunter, The Essex Landscape: A Study of Its Form and History [https://books.google.co.uk/books?id=w9kWAQAAIAAJ] *Cambridge County Geography [https://books.google.co.uk/books?id=GPHa_X_0qo0C&pg=PR3#v=onepage&q&f=false] *Sokoll. Essex  Pauper Letters, 1731-1837 [https://books.google.co.uk/books?id=rCLia7XlqtMC&pg=PP1#v=onepage&q&f=false] *Morant. The History and Antiquities of Colchester in the County of Essex [https://books.google.co.uk/books?id=DDgtAAAAYAAJ&pg=PP9#v=onepage&q&f=false] *Wallen. The History and Antiquities of the Round Church at Little Maplestead, Essex [https://books.google.co.uk/books?id=FPYVAAAAYAAJ&pg=PR1#v=onepage&q&f=false] Kent *Smith. Bibliotheca Cantiana. 1837. [https://books.google.co.uk/books?id=1dJDAAAAYAAJ&pg=PP11#v=onepage&q&f=false] Leicestershire *Kirkby, C V (compiler). Catalogue of the books, pamphlets, &c., relating to Leicestershire in the Central Reference Library. Leicester Free Public Libraries. 1893. Reviews: [https://books.google.co.uk/books?id=3boqAQAAIAAJ&pg=PA84#v=onepage&q&f=false] [https://books.google.co.uk/books?id=UcHnAAAAMAAJ&pg=PA728#v=onepage&q&f=false] *Leicestershire and Rutland Bibliography, 1963-65 (1966) [https://books.google.co.uk/books?id=-OhVAAAAYAAJ 40] Leicestershire Archaeological and Historical Society: Transactions (1964/5) 92. Available as pdf from University of Leicester. *Leicestershire and Rutland Bibliography, 1961-63. Available as pdf from University of Leicester. *Leicestershire and Rutland Bibliography, 1960-61. Available as pdf from University of Leicester. *A Bibliography of the Small Towns in Leicestershire and Rutland, 1600–1850. (Dissertation). [https://repository.lboro.ac.uk/articles/educational_resource/A_bibliography_of_the_small_towns_in_Leicestershire_and_Rutland_1600_1850/9414200] *Loughborough's Heritage: A Bibliography of the Holdings of Leicestershire Libraries and Information Service and Record Office. [https://books.google.co.uk/books?id=Bwx2zgEACAAJ] *Keith Ambrose and Frank Williams, "Bibliography of the Geology of Leicestershire and Rutland: Part 2: 1971-2003" (2004) [https://books.google.co.uk/books?id=U-tQAQAAIAAJ 16] The Mercian Geologist 5. Available as pdf from East Midlands Geological Society. *Parsons and Brandwood. A Bibliography of Leicestershire Churches. 1978. *Education in Leicestershire: A Bibliography. [https://books.google.co.uk/books?id=X6EfzQEACAAJ] Sussex *Brent, Fletcher and McCann. Sussex in the 16th and 17th Centuries: A Bibliography. 2nd Ed [https://books.google.co.uk/books?id=I7UtAAAAYAAJ] *Farrant. Sussex in the 18th and 19th Centuries: A Bibliography. 1st Ed: 1973, 2nd Ed: 1977 [https://books.google.co.uk/books?id=MLUtAAAAYAAJ], 3rd Ed: 1979 ==France== Bibliography: *Bibliographie de la France. Commentary: Encyclopedia of Library and Information Science, vol 37, supplement 2, [https://books.google.co.uk/books?id=10rgjNvOV8oC&pg=PA145#v=onepage&q&f=false p 145]; The Bookseller, 6 January 1881, [https://books.google.co.uk/books?id=4dsiAQAAMAAJ&pg=PA10#v=onepage&q&f=false p 10]; Stein, Manuel de bibliographie générale, [https://books.google.co.uk/books?id=lJYPyKjV1qYC&pg=PA23#v=onepage&q&f=false p 23]. *Girault de Saint-Fargeau. Bibliographie historique et topographique de la France. 1845 [https://books.google.co.uk/books?id=kClB9CQNZoMC&pg=PP9#v=onepage&q&f=false] *Catalogue d'une collection d'ouvrages sur l'histoire des provinces de la France. 1842 [https://books.google.co.uk/books?id=qQBX5WZouzAC&pg=PP1#v=onepage&q&f=false] Landscape: *Beaujeu-Garnier. France. (The World's Landscapes). 1975. [https://books.google.com/books?id=nwxDAQAAIAAJ] Agenais: *Andrieu. Bibliographie générale de l’Agenais et des parties du Condomois et du Bazadais. 1886 to 1891. Reprinted 1969. Alsace: *Ristelhuber. Bibliographie alsacienne. 1869 to 1873 [https://books.google.co.uk/books?id=0mhLAQAAMAAJ&pg=PP13#v=onepage&q&f=false] *Bibliographie alsacienne: Revue critique des publications concernant l'Alsace. 1918 to 1936 *Ritter. Répertoire bibliographique des livres imprimés en Alsace aux XVe et XVIe siècles [https://books.google.co.uk/books?id=DewaAQAAMAAJ] Angoumois: *Castaigne. Essai d'une bibliothèque historique de l'Angoumois, ou Catalogue raisonné des principaux ouvrages qui traitent des différentes branches de l'histoire de cette province. 1847 [https://books.google.co.uk/books?id=R-UanmmlvAEC&pg=PP7#v=onepage&q&f=false] Anjou: *Braguier and Braguier. Archéologie en Anjou: bibliographie. 1984 [https://books.google.co.uk/books?id=LvsmAQAAIAAJ] Auvergne: *Gonot. Catalogue des ouvrages imprimés et manuscrits concernant l'Auvergne, extrait du catalogue général de la Bibliotlèque de Clermont-Fd (Puy-de-Dome). 1849. [https://books.google.co.uk/books?id=yCFtbObRCbUC&pg=PP13#v=onepage&q&f=false] *Catalogue des livres et estampes concernant l'ancienne Province d'Auvergne (Puy-de-Dôme, Cantal, Haute-Loire) réunis par feu M. G. Desbouis. 1865. [https://books.google.co.uk/books?id=Ui4S8_D0N74C&pg=PP7#v=onepage&q&f=false] Béarn *"Bibliographie Béarnaise", Revue de Pau et du Béarn [https://books.google.co.uk/books?id=FuZnAAAAMAAJ] Commentary: [https://books.google.co.uk/books?id=FQYqvPo9D9IC&pg=PA158#v=onepage&q&f=false] [https://books.google.co.uk/books?id=RL9VAAAAYAAJ] Brittany *Sacher. Bibliographie de la Bretagne, ou Catalogue général des ouvrages historiques, littéraires et scientifiques parus sur la Bretagne, avec la liste des revues publiées en cette province, les prix approximatifs des volumes rares, etc. 1881 [https://archive.org/details/bibliographiede00sach] Burgundy: *Milsand. Bibliographie bourguignonne; ou, Catalogue méthodique d'ouvrages relatifs à la Bourgogne: Sciences - Arts - Histoire. 1885 [https://archive.org/details/bibliographiebo00milsgoog] [https://archive.org/details/bibliographiebo00sciegoog] [https://books.google.co.uk/books?id=CxIIAAAAQAAJ] *Catalogue des manuscrits de la Bibliothèque royale des ducs de Bourgogne. 1842 [https://books.google.co.uk/books?id=FX5MAAAAcAAJ&pg=PR3#v=onepage&q&f=false] *The Companion Guide to Burgundy [https://books.google.co.uk/books?id=NraRP0AkDT0C&pg=PP3#v=onepage&q&f=false] *Lecat. The Golden Book of Burgundy. (The Golden Book) [https://books.google.co.uk/books?id=FyzR9qU1Zl4C&lpg=PP1&pg=PP1#v=onepage&q&f=false] *Gwynn. Burgundy: With Chapters on the Jura and Savoy. (Kitbag Travel Books). 1935 [https://books.google.co.uk/books?id=ny1LAAAAMAAJ] *Bazin. Wonderful Burgundy. 1988. 1997 [https://books.google.co.uk/books?id=Yt1CRdICWCUC] *Bailey. Burgundy. (Insight Guides). 1993 [https://books.google.co.uk/books?id=Q69a1dMW2NQC] *Dunlop. Burgundy. Hamilton.1990 [https://books.google.co.uk/books?id=S_1OAAAAMAAJ] Champagne: *Lhermitte. Ouvrages sur la Champagne: contribution à la bibliographie champenoise. 1992. [https://books.google.co.uk/books?id=jbPfAAAAMAAJ] Dauphiné: *Mélanges biographiques et bibliographiques relatifs à l'histoire littéraire du Dauphiné par Colomb de Batines et Ollivier Jules. 1837 [https://books.google.co.uk/books?id=2F5MAAAAcAAJ&pg=PR3#v=onepage&q&f=false] Lorraine: *Bibliographie lorraine. Académie nationale de Metz [https://books.google.co.uk/books?id=n-DfAAAAMAAJ] Maine: *Desportes. Bibliographie du Maine, précédée de la description topographique et hydrographique du diocése du Mans, Sarthe et Mayenne. 1844. [https://books.google.co.uk/books?id=hSk-AAAAYAAJ&pg=PR3#v=onepage&q&f=false] Normandy: *Frère. Manuel du bibliographe Normand ou dictionnaire bibliographique et historique. 1858 to 1860. [https://books.google.co.uk/books?id=dp6geJClg1YC&pg=PP13#v=onepage&q&f=false vol 1] ==Japan== Bibliography and literature *Hideo Kaneko. "Japanese Literature and Bibliography". Kent, Lancour and Daily (eds). Encyclopedia of Library and Information Science. Marcel Dekker. 1977. vol 21. pp [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA131#v=onepage&q&f=false 131] to 176. Bibliography *Jozef Rogala. A Collector's Guide to Books on Japan in English: An Annotated List of Over 2500 Titles with Subject Index. 2001. [https://books.google.co.uk/books?id=7KI9ao-w2FEC&pg=PP1#v=onepage&q&f=false] *Ria Koopmans-de Bruijn. Area Bibliography of Japan. (Scarecrow Area Bibliographies). Scarecrow Press. 1998. [https://books.google.co.uk/books?id=Hlx2OMjgUi0C&pg=PR1#v=onepage&q&f=false] *Frank Joseph Shulman. Japan. (World Bibliographical Series, vol 103). Clio Press. 1989. [https://books.google.co.uk/books?id=LsoUAQAAIAAJ] *Eibun Nihon Kankei Tosho Mokuroku, 1945-1981. (Japanese: 英文日本関係図書目録, 1945-1981). (English: Catalogue of Books in English on Japan, 1945-1981). Japan Foundation. Tokyo. 1986. *Japan: analytical bibliography: with supplementary research aids: and selected data on Okinawa . . . Department of the Army. Washington. 1972. [https://books.google.co.uk/books?id=h4d4nYxrxtMC&pg=PP7#v=onepage&q&f=false] *Books on Japan in Western Languages. The International Christian University Library. 1971. [https://books.google.co.uk/books?id=F2bQAAAAMAAJ] *Books on Japan: A List of Acquisitions, 1955-1970. International House of Japan Library. 1971. [https://books.google.co.uk/books?id=F8sWAQAAIAAJ] *Fukuda. Union Catalog of Books on Japan in Western Languages. 1968. [https://books.google.co.uk/books?id=HKYyAQAAIAAJ] *A Classified List of Books in Western Languages Relating to Japan. University of Tokyo Press. 1965. [https://books.google.co.uk/books?id=U8MUAQAAIAAJ] *Katsuji Yabuki (ed). Japan Bibliographic Annual. Published by the Hokuseido Press for the Japan Writers Society. 1956 and 1957. **Japan Bibliographic Annual 1956. [https://books.google.co.uk/books?id=9XLQAAAAMAAJ] **Japan Bibliographic Annual 1957. [https://books.google.co.uk/books?id=vesSAAAAIAAJ]. Reviews: (1957) 13 Monumenta Nipponica 166 (April-July) [https://books.google.co.uk/books?id=8S1yb-iwrOwC] (1957) 25 The Oriental Economist 212 (April) [https://books.google.co.uk/books?id=QELoAAAAMAAJ] *Haring. Books on Japan: A Reference List. 1955. [https://books.google.co.uk/books?id=RbDoAAAAMAAJ] *Borton. A Selected List of Books and Articles on Japan in English, French, and German. 1940: [https://books.google.co.uk/books?id=YYIsAAAAYAAJ]. Revised and enlarged. Harvard University Press. 1954: [https://books.google.co.uk/books?id=F8O2VwJUPUkC]. **A Selected List of Books on Japan in Western Languages (1945-1960). (Studies on Asia Abroad, vol 1). The Information Centre of Asian Studies, The Toyo Bunko. 1964. [https://books.google.co.uk/books?id=i1_QAAAAMAAJ] *Oskar Nachod. Bibliography of the Japanese Empire 1906-1926. 1928. [https://archive.org/details/bibliographyofja0001oska/page/n8/mode/1up vol 1]. [https://archive.org/details/bibliographyofja0002oska/page/n6/mode/1up vol 2]. *Fr. von Wenckstern. A Bibliography of the Japanese Empire: being a Classified List of All Books, Essays and Maps in European Languages relating to Dai Nihon (Great Japan) published in Europe, America and in the East from 1859-93 . . . 1895. vol 1. [https://books.google.co.uk/books?id=dcVAAAAAYAAJ&pg=PR1#v=onepage&q&f=false] [https://books.google.co.uk/books?id=v7lO4ddqDywC&pg=PR3#v=onepage&q&f=false] **Volume 2, from 1894 to the middle of 1906. 1907. [https://archive.org/details/bibliographyofja0002frvo/page/n6/mode/1up] *Hyman Kublin. What Shall I Read on Japan? An Introductory Guide. Japan Society, New York. 1971. [https://books.google.co.uk/books?id=yRRUAAAAYAAJ] *Henri Cordier. Bibliotheca Japonica: Dictionnaire Bibliographique des Ouvrages Relatifs a L'Empire Japonais. 1912. [https://archive.org/details/bibliothecajapon0008henr/page/n8/mode/1up] Japanese studies *An Introductory Bibliography for Japanese Studies. The Japan Foundation. [https://books.google.co.uk/books?id=53O6AAAAIAAJ] *Richard Perren. Japanese Studies from Pre-History to 1990: A Bibliographical Guide. 1992. [https://books.google.co.uk/books?id=CN9RAQAAIAAJ&pg=PP1#v=onepage&q&f=false]. "Bibliographies" at pp 1 to 3. *K.B.S. Bibliography of Standard Reference Books for Japanese Studies, with Descriptive Notes. University of Tokyo Press. [https://books.google.co.uk/books?id=95wbAAAAMAAJ] *[[w:en:Monumenta Nipponica|Monumenta Nipponica]] *[[w:en:Japan Forum|Japan Forum]]. British Association for Japanese Studies. [https://www.tandfonline.com/journals/rjfo20] *Japanese Studies. Japanese Studies Association of Australia. ISSN 1037-1397. [https://www.tandfonline.com/journals/cjst20] *[[w:en:The Journal of Japanese Studies|The Journal of Japanese Studies]]. University of California Press. *Nichibunken Newsletter. [[w:en:International Research Center for Japanese Studies|International Research Center for Japanese Studies]]. [https://books.google.co.uk/books?id=5TnjAAAAMAAJ] [https://www.nichibun.ac.jp/en/publications/data/news/] [https://newsletter.nichibun.ac.jp/en/] History and culture *John W Dower. Japanese History & Culture from Ancient to Modern Times: Seven Basic Bibliographies. 1986. [https://books.google.co.uk/books?id=NX67AAAAIAAJ&pg=PP1#v=onepage&q&f=false]. "Bibliographies & Research Guides" at chapter 6. Research guides *Mindy L Kotler. Information Gathering on Japan: A Primer. Search Associates. 1988. ISBN 9780962546006. Catalogue: [https://search.worldcat.org/zh-cn/title/Information-gathering-on-Japan-Joho-:-a-primer/oclc/20530148]. Review: (1989) [https://books.google.co.uk/books?id=NZLiAAAAMAAJ 27] Choice 82 Encyclopedias See also [[w:ja:Japanese encyclopedias]] *Louis Frédéric. [[w:Japan Encyclopedia|Japan Encyclopedia]]. Translated by Käthe Roth. 2002. [https://books.google.co.uk/books?id=p2QnPijAEmEC&pg=PP1#v=onepage&q&f=false] **Louis Frédéric. Le Japon: Dictionnaire et Civilisation. Robert Lafont. Paris. 1996. ISBN 2-221-06764-9. *Japan: An Illustrated Encyclopedia. Kodansha. 1993. **Japan: Profile of a Nation. Kodansha. 1995. Revised Edition. 1999. *[[w:Kodansha Encyclopedia of Japan|Kodansha Encyclopedia of Japan]]. 1983. Supplement. 1986. [https://books.google.co.uk/books?id=WvApAQAAMAAJ] *Dorothy Perkins. Encyclopedia of Japan: Japanese History and Culture, from Abacus to Zori. Facts on File. A Roundtable Press Book. 1991. [https://books.google.co.uk/books?id=JLKGAAAAIAAJ] *Pictorial Encyclopedia of Modern Japan. Gakken. 1986. [https://books.google.co.uk/books?id=0FgKAQAAIAAJ] *Boye Layfayette De Mente. Japan Encyclopedia. 1995. [https://books.google.co.uk/books?id=f9c7AAAAMAAJ] **Boye De Mente. Everything Japanese. [The Authoritave Reference on Japan Today]. 1989. [https://books.google.co.uk/books?id=Duku89bARgoC] Biographical dictionaries *Wispelway. Japanese Biographical Index [https://books.google.co.uk/books?id=4UkhAAAAQBAJ&pg=PR3#v=onepage&q&f=false] *Seiichi Iwao. Biographical Dictionary of Japanese History. Kodansha International. 1978.[https://books.google.co.uk/books?id=TkQOAQAAMAAJ] *Senʼichi Hisamatsu. Biographical Dictionary of Japanese Literature. Kodansha International. 1976. [https://books.google.com/books?id=X3lkAAAAMAAJ] *Yutaka Tazawa (ed). Biographical Dictionary of Japanese Art. Kodansha International. 1981. [https://books.google.com/books?id=7ozrAAAAMAAJ] *Japan Biographical Encyclopedia & Who's Who. 1958. Review: [https://books.google.co.uk/books?id=lV_VAAAAMAAJ 25] Contemporary Japan 280 **Japan Biographical Encyclopedia & Who's Who (2nd Edition) 1961. The Japan Biographical Research Department, The Rengo Press Ltd. Preface dated October 1960. Commentary: [https://books.google.co.uk/books?id=-SZSAAAAMAAJ] ***1961 Supplement. December 1961. *Shunjiro Kurita. [[w:ja:Who's Who in Japan|Who's Who in Japan]]. [https://archive.org/details/WhosWhoInJapan1913/page/n24/mode/1up 2nd Ed]. Catalogue: [https://cir.nii.ac.jp/crid/1971712334741056302]. **[[w:ja:石川安次郎|Yasujiro Ishikawa]] (ed). Fifth Annual Edition. The Who's Who in Japan Publishing Department: The Keiseisha. No 15, 2-chome, Owari-cho, Ginza, Kyobashi-ku, Tokyo. Preface dated May 1916. [https://books.google.co.uk/books?id=joBJAAAAYAAJ]. Yasujiro Ishikawa's biography "Ishikawa Yasujiro" is on p 213. Reference books *Nihon No Sanko Tosho. Volume 1: 1965. Volume 2: 1972. **Guide to Japanese Reference Books. American Library Association. Chicago. 1966: [https://books.google.co.uk/books?id=0rflAAAAMAAJ]. Supplement. 1979: [https://books.google.co.uk/books?id=j05_F9OHzkQC]. Commentary: Encyclopedia of Library and Information Science, vol 21, [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA149#v=onepage&q&f=false p 149]. Media *[https://www.bbc.com/news/world-asia-pacific-15217593 Japan media guide]. News. BBC. 20 March 2023. *Masaaki Kasagi. Mass Media in Japan. (Orientation seminars on Japan, number 14). 1983. [https://books.google.co.uk/books?id=odkgAAAAIAAJ] *Routledge Handbook of Japanese Media [https://books.google.co.uk/books?id=zilKDwAAQBAJ&pg=PA1#v=onepage&q&f=false] Publishers *[https://www.publishersweekly.com/pw/by-topic/international/international-book-news/article/99729-get-to-know-these-japanese-publishing-companies.html Get to Know These Japanese Publishing Companies]. Publishers Weekly. 20 February 2026. Press and journalism *[https://reutersinstitute.politics.ox.ac.uk/digital-news-report/2025/japan Japan]. Reuters Institute for the Study of Journalism. 17 June 2025. *Marjane Aalam and Philippe Régnier. The Japanese Press and Information System. The Graduate Institute of International Studies. Geneva. [https://books.google.co.uk/books?id=RTcbAQAAIAAJ] *The Japanese Press: Past and Present. Japan Newspaper Publishers' and Editors' Association. [https://books.google.co.uk/books?id=5tcQAAAAIAAJ 1949]. *Anthony Rausch. Japanese Journalism and the Japanese Newspaper: A Supplemental Reader. [https://books.google.co.uk/books?id=mZrToQEACAAJ] *Frank L Martin. The Journalism of Japan. 1918. [https://books.google.com/books?id=ruYzAQAAMAAJ] *William De Lange. A History of Japanese Journalism. Japan Library. 1998. [https://books.google.co.uk/books?id=Rd5tb0cuz8QC&pg=PP1#v=onepage&q&f=false] *Kanesada Hanazono. The Development of Japanese Journalism. Osaka. 1924. [https://books.google.co.uk/books?id=z99ZAAAAMAAJ] *Kanesada Hanazono. Journalism in Japan and Its Early Pioneers. 1926. [https://books.google.co.uk/books?id=IGTFfLc4bq0C] *César Castellvi. A Sociology of Journalism in Japan: The Last Empire of the Press. 2024. [https://books.google.co.uk/books?id=a2z8EAAAQBAJ&pg=PR4#v=onepage&q&f=false] *"Japan". Christopher H Sterling (ed). Encyclopedia of Journalism. A Sage Reference Publication. 2009. ISBN 9780761929574. vol 3. pp [https://books.google.co.uk/books?id=ZQhDq8fPj2IC&pg=PA809#v=onepage&q&f=false 809] to 815. Press annuals *The Japanese Press. (Nihon Shinbun Kyokai). [https://books.google.co.uk/books?id=AfvyAAAAMAAJ 1979] [https://books.google.co.uk/books?id=Au3yAAAAMAAJ 1998] Summaries of the press *Daily Summary of Japanese Press Foreign correspondents *Foreign Correspondents in Japan: Reporting a Half Century of Upheavals, from 1945 to the Present. Tuttle. 1998. [https://books.google.co.uk/books?id=YI3TAgAAQBAJ&pg=PP1#v=onepage&q&f=false] Periodicals *G Raymond Nunn (comp). Japanese Periodicals and Newspapers in Western Languages: An International Union List. Mansell. 1979. [https://books.google.co.uk/books?id=jEROAQAAIAAJ] *Japan Periodicals. Keizai Koho Center. 3rd Ed [https://books.google.co.uk/books?id=ATm0AAAAIAAJ]. Japan Periodicals, 1982. [https://books.google.co.uk/books?id=PkMyAAAAMAAJ] *Japanese Periodicals Index **Humanities and Social Sciences [https://books.google.co.uk/books?id=nXX_RpPGf3AC] **Natural Sciences [https://books.google.co.uk/books?id=FCJIAAAAYAAJ] *Current Japanese Periodicals [https://books.google.co.uk/books?id=FjO5AAAAIAAJ] *Check-list of Japanese Periodicals Held in British University and Research Libraries. [https://books.google.co.uk/books?id=VZgsAAAAYAAJ] *Union List of Current Japanese Periodicals in the East Asian Libraries of Columbia, Harvard, Princeton, and Yale Universities. [https://books.google.co.uk/books?id=yw7kAAAAMAAJ] *List of Japanese Periodicals in the Library of the School of Oriental & African Studies. [https://books.google.co.uk/books?id=RREjAQAAIAAJ] *Gianni Simone. [https://www.japantimes.co.jp/community/2011/04/26/issues/english-mags-approach-milestone-crossroads/ English mags approach milestone, crossroads]. The Japan Times. 26 April 2011. *Japan Report (1955 onwards) (Consulate General of Japan, Japan Information Center). Vol 39 published in 1993. [https://books.google.co.uk/books?id=MX4BN_frv4IC&pg=PP7#v=onepage&q&f=false] editions:jYuMSMIQC-AC **Japan Information *Japan Now [https://books.google.co.uk/books?id=Nul7DRQaexMC&pg=PP7#v=onepage&q&f=false] *Japan Quarterly. (Asahi Shimbun). 1954 to 2001. [https://books.google.co.uk/books?id=nZMMAQAAMAAJ] [https://books.google.co.uk/books?id=_RwVAAAAMAAJ] 189 issues. *Japan Illustrated: The Japan Times Quarterly [Pictorial] Magazine (October 1963 to Summer 1977) 15 vols [https://books.google.co.uk/books?id=D7UThOmE8T4C] *[[w:Japan Spotlight|Japan Spotlight]]. Economy, Culture & History: Japan Spotlight: Bimonthly. [https://books.google.co.uk/books?id=i7C0AAAAIAAJ] *Focus Japan. (Japan External Trade Organization, JETRO). [https://books.google.co.uk/books?id=2fG2hsEZpRkC] *The Japan Journal [https://books.google.co.uk/books?id=2V3hAAAAMAAJ] [https://books.google.co.uk/books?id=CJwoAQAAMAAJ] *Japan Magazine. Muromachi Publicity Corporation. (vols 1 to 5: 1957 to 1963). [https://books.google.co.uk/books?id=Swd18PnVeUgC] *The Japan Magazine: A Representative Monthly of Things Japanese [https://books.google.co.uk/books?id=ubGKo-p6O_0C] [https://archive.org/details/jm-1914-v4.9-5.2/mode/1up] *Transactions and Proceedings of the Japan Society, London [https://books.google.co.uk/books?id=B75nnph5qHgC&pg=PP5#v=onepage&q&f=false] **Bulletin. [Bulletin of the Japan Society, London.] [https://books.google.co.uk/books?id=Pd9KvyhnpjMC] **The Japan Society of London Bulletin [https://books.google.co.uk/books?id=XxlxAAAAMAAJ] *About Japan. Japan Society, New York. [https://books.google.co.uk/books?id=Nf5OAQAAIAAJ] **News Bulletin [https://archive.org/details/bub_gb_QcA3AQAAIAAJ/page/n2/mode/1up] *[[w:en:Metropolis (free magazine)|Metropolis]] (metropolisjapan.com) *[[w:en:Tokyo Weekender|Tokyo Weekender]] (トーキョー・ウィークエンダー) [https://www.tokyoweekender.com/japan-life/news-and-opinion/nhk-world-features-the-tokyo-weekender-magazine/] *The Japan Gazette [https://books.google.co.uk/books?id=WSopAAAAYAAJ&pg=PA1#v=onepage&q&f=false] *The Tokio Times [https://books.google.co.uk/books?id=UDfiFBu0vB4C&pg=PA1#v=onepage&q&f=false] *[[w:en:Look Japan|Look Japan]]. (Look Japan Ltd). [https://books.google.co.uk/books?id=QnO6AAAAIAAJ]. Commentary: Gale Directory of Publications and Broadcast Media [https://books.google.co.uk/books?id=ve4dAQAAMAAJ] *[[w:en:Japan Echo|Japan Echo]]. 1974 to 2010. [https://books.google.co.uk/books?id=Cmq6AAAAIAAJ] [https://books.google.co.uk/books?id=fpmEPpl-85UC] *PHP Intersect. (Where Japan Meets Asia and the World). PHP Institute. [https://books.google.co.uk/books?id=i74TAQAAMAAJ] **Intersect Japan [https://books.google.co.uk/books?id=sL8TAQAAMAAJ] *Japan Digest [https://books.google.co.uk/books?id=8AcOAQAAMAAJ] *Speaking of Japan [https://books.google.co.uk/books?id=U7S0AAAAIAAJ]. [Speeches.] *The Hansei Zasshi: A Monthly Magazine [https://books.google.co.uk/books?id=6qBhfHZo7Q0C&pg=PP5#v=onepage&q&f=false][https://books.google.co.uk/books?id=dyIsvnYjpwEC&pg=PP6#v=onepage&q&f=false] **The Orient. 1899 onwards [https://books.google.co.uk/books?id=nS1omYYnnd4C&pg=PP5#v=onepage&q&f=false] *Today's Japan. Orient/West Incorporated. [https://books.google.co.uk/books?id=g2ASAAAAMAAJ] *Japan Review: Bulletin of the International Research Center for Japanese Studies. [https://books.google.co.uk/books?id=GggOAQAAMAAJ] *[https://www.bloomberg.com/account/newsletters/next-japan Next Japan]. Bloomberg. *Niponica. [https://books.google.co.uk/books?id=X2scKgfQS5oC] Newspapers See also [[w:List of newspapers in Japan]] *Haruhara Akihiko, "English-language newspapers in Japan" (1994) 41 Japan Quarterly [https://www.proquest.com/openview/8e2b760f2a2fa37ba164ea675c095353/1 474] (Issue 4: October 1994) *James Charles Tanner. English Language Newspapers in Bakumatsu Japan. 1977. [https://books.google.co.uk/books?id=Bn2zgzZy_3oC] *[https://www.japantimes.co.jp/news/2009/03/03/reference/newspapers-here-soldiering-on/ Newspapers here soldiering on]. The Japan Times. 3 March 2009. *[[w:The Japan Times|The Japan Times]] **The Japan Times: Weekly Edition [https://books.google.co.uk/books?id=KoQ-AQAAMAAJ] [https://books.google.co.uk/books?id=yYQ-AQAAMAAJ&pg=PA1#v=onepage&q&f=false] *Japan Daily Mail *Japan Weekly Mail *The Japan Chronicle **Weekly Edition [https://books.google.co.uk/books?id=vXdRAQAAIAAJ&pg=PA1#v=onepage&q&f=false] *The Japan News. (The Japan News by The Yomiuri Shimbun) **Yomiuri Japan News (from 1955) **The Yomiuri (from 1958) **The Daily Yomiuri (from 1970) *The Asahi Shimbun: Asia & Japan Watch. [https://www.asahi.com/sp/ajw/] **Asahi Evening News (from 1954) ***Tokyo Evening News (1952 to 1954) [https://ndlsearch.ndl.go.jp/books/R100000002-I000000145073] *The Mainichi. [https://mainichi.jp/english/] **Mainichi Daily News (1922 to 2001) [https://www.nytimes.com/2001/02/27/business/worldbusiness/IHT-tech-briefstop-the-presses.html] [https://ndlsearch.ndl.go.jp/books/R100000002-I000000144910] Sports newspapers; sports dailies *Louise do Rosario, "News-stand stars" in "Japan" (1992) [https://books.google.co.uk/books?id=T_GzAAAAIAAJ 155] [[w:en:Far Eastern Economic Review|Far Eastern Economic Review]], 24 to 31 December 1992, p 21 *[[w:ja:岡崎満義|Mitsuyoshi Okazaki]], "Unsportsmanlike Journalism: Japan's sports dailies may be popular, but are they sporting?" in "Sport", [[w:en:Look Japan|Look Japan]], [https://books.google.co.uk/books?id=lD3tAAAAMAAJ January 1995], p 39 News *[[w:en:Japan Today|Japan Today]] (ジャパントゥデイ). GPlusMedia. Gakken Holdings. Annuals and year books *This is Japan. Asahi Shimbun. 1954 to 1971. [https://books.google.co.uk/books?id=2X9DAQAAIAAJ]. Commentary: A Victorian Sailor's Grave in the Seto Inland Sea, p 244 [https://books.google.co.uk/books?id=OegkAgAAQBAJ&pg=PA244#v=onepage&q&f=false] *The Japan Year Book. The Japan Year Book Office. 1905 onwards. [https://archive.org/details/bub_gb_arFPAAAAMAAJ/page/n10/mode/1up 1906]. [https://archive.org/details/in.ernet.dli.2015.553496/page/n27/mode/1up 1915]. *The "Japan Gazette" Japan Year Book. The Japan Gazette. [https://archive.org/details/japan-year-book-1913-1914/page/n15/mode/1up 1913-14] *The Japan Times Year Book *New Japan. Mainichi Newspapers. [https://books.google.co.uk/books?id=gRFCAQAAIAAJ] Almanacs *Asahi Shimbun Japan Almanac. [https://books.google.co.uk/books?id=SEEEAQAAIAAJ 1995]. *Japan Almanac. (The Mainichi Newspapers). [https://books.google.co.uk/books?id=ufAIAQAAIAAJ 1972]. [https://books.google.co.uk/books?id=X4eXWRkbtFsC 1973]. [https://books.google.co.uk/books?id=7rMrAAAAIAAJ] [https://books.google.co.uk/books?id=krMrAAAAIAAJ] *[[w:Boyé Lafayette De Mente|Boye De Mente]]. Passport's Japan Almanac. [https://books.google.co.uk/books?id=741wAAAAMAAJ] General *Japan: A Country Study. (Area Handbook series). 4th Ed: 1983: [https://books.google.co.uk/books?id=HkM5N3JNc5IC]. 5th Ed: 1992: [https://books.google.co.uk/books?id=ze-wupXxpvEC] *Area Handbook for Japan. 2nd Ed: 1964: [https://books.google.co.uk/books?id=WucdAAAAMAAJ&pg=PR1#v=onepage&q&f=false]. 3rd Ed: 1974: [https://books.google.co.uk/books?id=LG2aoq1U_eoC&pg=PR1#v=onepage&q&f=false] (DA Pam 550-30). *Colin Simpson. Picture of Japan. **Japan: An Intimate View. A S Barnes. [https://books.google.co.uk/books?id=3hkeAAAAMAAJ] **This is Japan. Angus & Robertson. [https://books.google.co.uk/books?id=HJEJAQAAIAAJ] *Japan. (The World and Its Peoples). Greystone Press, New York. 1964. Volume 1: [https://books.google.co.uk/books?id=yysUAQAAMAAJ]. Volume 2 "Japan Korea", including Korea: [https://books.google.co.uk/books?id=uQAUAQAAMAAJ]. See pp 1 to 375 for Japan, and pp 376 to 379 for Ryukyu and Bonin Islands. *Japan. (World and its Peoples: Eastern and Southern Asia, volume 8). Marshall Cavendish. 2008. ISBN 9780761476412. *Edward Seidensticker. This Country, Japan. Kodansha International. 1979. ISBN 9780870112294. [https://books.google.co.uk/books?id=88wwAQAAIAAJ] *Hall and Beardsley. Twelve Doors to Japan. McGraw-Hill. New York. 1965. [https://books.google.co.uk/books?id=0KpxAAAAMAAJ] *"Japan". Louis Barron (ed). "Asia & Australasia". Moshe Y Sachs (ed and pub). Worldmark Encyclopedia of the Nations. Worldmark Press, Inc. Harper & Row New York. 1963. pp 145 to 160. [https://books.google.co.uk/books?id=I0oYAQAAMAAJ] **"Japan". Asia & Oceania. 7th Ed: 1988. ISBN 0-471 62406-3. vol 4. pp 153 to 168. **"Japan". Asia & Oceania. 8th Ed: 1995. Gale Research Inc. ISBN 0-8103-9882-6. vol 4. pp 203 to 220. *James E Hoare. "Japan". East and Southeast Asia. The World Today Series 2023–2024. pp [https://books.google.co.uk/books?id=3GfQEAAAQBAJ&pg=PA107#v=onepage&q&f=false 107] to 133. *Japan. (Library of Nations). Time Life Books. 1985. ISBN 0809453347. ISBN 0705408485. [https://books.google.co.uk/books?id=P1NJwcWAnboC] [https://books.google.co.uk/books?id=Ui2CvuyM4JkC] Handbooks *Patrick Heenan (ed). The Japan Handbook. (Regional Handbooks of Economic Development). 1998. [https://books.google.co.uk/books?id=IMG2AgAAQBAJ&pg=PP1#v=onepage&q&f=false] Introduction *Introducing Japan Through Books: A Selected Bibliography. Public Information Bureau, Ministry of Foreign Affairs, Japan. 1968. [https://books.google.co.uk/books?id=FvsyAQAAIAAJ]. 2nd Ed: 1973: [https://books.google.co.uk/books?id=Vj0XAQAAMAAJ]. *Donald Ritchie. Introducing Japan. 1st Ed: 1978. Revised Ed: 1986. 6th printing: 1989: [https://books.google.co.uk/books?id=FE-nxxoKayQC]. 2nd Revised Ed: 1990. 2nd printing: 1991: [https://books.google.co.uk/books?id=hz4UAQAAIAAJ]. 1994: [https://books.google.co.uk/books?id=FMvT6m4SgIQC&pg=PP1#v=onepage&q&f=false]. *Herschel Webb. An Introduction to Japan. Columbia University Press. 2nd Ed: 1957: [https://books.google.co.uk/books?id=YQ8MAQAAIAAJ]. *Introducing Modern Japan. A publication of the Japan Information and Culture Center, Embassy of Japan. Today and yesterday *Ray Downs. Japan Yesterday and Today. Praeger Publishers. 1970. [https://books.google.co.uk/books?id=PwKxAAAAIAAJ] Today *Roger Buckley. Japan Today. Cambridge University Press. 3rd Ed [https://books.google.co.uk/books?id=thyqBtJp2DcC&pg=PP1#v=onepage&q&f=false] Contemporary *Routledge Handbook of Contemporary Japan. 2021. [https://books.google.co.uk/books?id=yfH3DwAAQBAJ&pg=PA2011#v=onepage&q&f=false] *Duncan McCargo. Contemporary Japan. 3rd Ed: 2012. [https://books.google.co.uk/books?id=8I5KEAAAQBAJ&pg=PP1#v=onepage&q&f=false] *Jeff Kingston. Contemporary Japan: History, Politics, and Social Change since the 1980s. 2011. [https://books.google.co.uk/books?id=enJQZA3R4FMC&pg=PP1#v=onepage&q&f=false] [Series] *Routledge Contemporary Japan Series Modern *Hugh Cortazzi. Modern Japan: A Concise Survey. Palgrave Macmillan. 1993. [https://books.google.co.uk/books?id=Cf--DAAAQBAJ&pg=PP1#v=onepage&q&f=false] The Japanese *Peter Tasker. The Japanese: Portrait of a Nation. 1989 [https://books.google.com/books?id=Q1N8ld78wwQC] **The Japanese: A Major Exploration of Modern Japan. [https://books.google.co.uk/books?id=CW-6AAAAIAAJ] **Inside Japan: Wealth, Work and Power in the New Japanese Empire. 1987. [https://books.google.co.uk/books?id=2OJuAAAAMAAJ] *Edwin O Reischauer. The Japanese. The Belknap Press of Harvard University Press. [https://books.google.co.uk/books?id=zrEqAAAAYAAJ] *Edwin O Reischauer and Marius B Jansen. The Japanese Today: Change and Continuity. 1995. [https://books.google.co.uk/books?id=BTPNlLIy2soC&pg=PP1#v=onepage&q&f=false] Japaneseness *Ray T. Donahue (ed). Exploring Japaneseness: On Japanese Enactments of Culture and Consciousness. Ablex Publishing. 2002. [https://books.google.co.uk/books?id=V_NwAAAAMAAJ] *Yoji Yamakuse. Japaneseness: A Guide to Values and Virtues. 2016. [https://books.google.co.uk/books?id=tB0iDAAAQBAJ&pg=PP1#v=onepage&q&f=false] Travel books *DK Eyewitness Travel: Japan. Reprinted with revisions. 2015: [https://books.google.co.uk/books?id=g2NaBgAAQBAJ&pg=PP1#v=onepage&q&f=false]. 2017: [https://books.google.co.uk/books?id=vg15DQAAQBAJ&pg=PP1#v=onepage&q&f=false]. *Dodd and Richmond. The Rough Guide to Japan. 2nd Ed: 2001: [https://books.google.co.uk/books?id=pRGq95ytWZoC&pg=PP1#v=onepage&q&f=false]. *Frommer's Japan. 5th Ed: 2000: [https://books.google.co.uk/books?id=-QC8mVyvPa8C]. *Fodor's Japan YYYY. 1984. [https://books.google.co.uk/books?id=aH2Ow27HUQ0C 1986]. [https://books.google.co.uk/books?id=3gTTf6nbv20C 1987]. 1988. **Fodor's YY Japan. [https://books.google.co.uk/books?id=9QMHllzldlYC 91]. 92. 93. **Fodor's Japan. 13th Ed: 1996: [https://books.google.co.uk/books?id=cZxZAAAAYAAJ] *The New Official Guide: Japan. Japan Travel Bureau. 1966. [https://books.google.co.uk/books?id=HoxxAAAAMAAJ] *Here is Japan. Asahi Broadcasting Corporation. [https://books.google.co.uk/books?id=8QXRCTMNG7MC] *Japan. (Nagel Travel Guide Series, vol 32). 1964. [https://books.google.co.uk/books?id=QsbXAAAAMAAJ] *Clark. All the Best in Japan: with Manila, Hong Kong, and Macao. ("All the Best" series). 1959. Reprinted 1964. [https://books.google.co.uk/books?id=yUq4YaaryrwC]. Reviews: [https://archive.dartmouthalumnimagazine.com/article/1958/6/1/all-the-best-in-japan] (1958) 110 Travel 51 [https://books.google.co.uk/books?id=UVwXAQAAMAAJ] 3 Bulletin of the Japan Society, London, No 11: June 1960, p 25 [https://books.google.co.uk/books?id=2oy74hRRXk4C] **All the Best in Japan and the Orient. 1967. Night *[[w:ja:Taizo Fujimoto|Taizo Fujimoto]]. The Nightside of Japan. T Werner Laurie. Essex Street, Strand, London. 1914. [https://archive.org/details/nightsideofjapan00fujirich/page/n6/mode/1up] Exhibitions *Patricia Morison. "Fun and games with Japanese angst". The Financial Times. Weekend 21/22 September 1991. No 31562. Section II: "Weekend FT". Weekend 21/22 September 1991. Page xx. ["Visions of Japan" exhibition, Victoria and Albert Musuem, ending 5 January 1992.] Languages See [[Universal Bibliography/Languages/Japanese|Japanese]] Literature See [[Universal Bibliography/Literature#Japanese|Japanese literature]] Music See [[Universal Bibliography/Music#Japanese and Japan|Music of Japan]] Cinema See [[Universal Bibliography/Cinema#Japanese|Cinema of Japan]] Television See [[Universal Bibliography/Television#Japanese|Japanese television]] Architecture See [[Universal Bibliography/Architecture|Japanese architecture]] Culture See [[Universal Bibliography/Culture#Japanese|Culture of Japan]] Economy *MERI's Monthly Circular: Survey of Economic Conditions in Japan (1923 to 2025) Mitsubishi Economic Research Institute [https://books.google.co.uk/books?id=4QDtAAAAMAAJ] [https://www.meri.or.jp/en/mc.html] Tokyo *J S Eades. Tokyo. (World Bibliographical Series, vol 214). CLIO Press. 1999. ISBN 1-85109-292-7. [https://books.google.co.uk/books?id=TrkUAQAAIAAJ] ==Korea== *Korea Journal [https://books.google.co.uk/books?id=O6XfBexsp6gC] Bibliography and literature *Thomas H Kang. "Korean Literature and Bibliography". Kent, Lancour and Daily (eds). Encyclopedia of Library and Information Science. Marcel Dekker. 1977. vol 21. pp [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA176#v=onepage&q&f=false 176] to 240. [[Category:Countries]] 9ziz8idkq9x4wlo7lkm8b6o3o1byd1z 2844883 2844881 2026-11-08T17:07:34Z James500 297601 /* Japan */ Add 2844883 wikitext text/x-wiki {{Bibliography}} See also [[Universal Bibliography/Geography|Geography]]. See [[w:Category:Bibliographies of countries or regions]] and [[w:Category:Works about countries]]. This part of the [[Universal Bibliography]] is a bibliography of countries (including former countries). ==Countries== *Bateman and Egan (eds). The Encyclopedia of World Geography: A Country by Country Guide. 1993. Revised 1997. *Peter Stalker. Handbook of the World. 2000. A Guide to Countries of the World. (Oxford Guide to Countries of the World. 2nd Ed: 2004, 2nd Revised Ed: 2007 [https://books.google.co.uk/books?id=GtztAAAAMAAJ], 3rd Ed: 2010 [https://books.google.co.uk/books?id=gvKvfxkbZ1AC&pg=PP1#v=onepage&q&f=false] *Countries of the World and Their Leaders Yearbook. Gale. [https://books.google.co.uk/books?id=5etKAAAAYAAJ] [https://books.google.co.uk/books?id=p41OAAAAIAAJ] *Hutchinson Guide to Countries of the World [https://books.google.co.uk/books?id=GgpjUe4kN_IC] *The World Guide: Global Reference, Country by Country. 11th Ed: 2007 [https://books.google.co.uk/books?id=EoWoLgAACAAJ] *Spence. The World Today: A Nation-by-Nation Guide. Cassell. 1994. 1999. [https://books.google.com/books?id=Ub8qOQAACAAJ] *Worldmark Encyclopedia of the Nations [https://books.google.co.uk/books?id=I0oYAQAAMAAJ] *Kurian. Encyclopedia of the World's Nations. Facts on File. Reviews: [https://books.google.co.uk/books?id=Y1EnAQAAIAAJ] [https://books.google.co.uk/books?id=lz0RAQAAMAAJ] *Michael O'Mara. Facts about the World's Nations. 1999. [https://books.google.co.uk/books?id=mygYAAAAIAAJ] *Status of the World's Nations. 1965 [https://books.google.co.uk/books?id=sftEyRbAXMUC&pg=PP1#v=onepage&q&f=false]. 1973 [https://books.google.co.uk/books?id=kw2U_Cg2gKYC&pg=PP3#v=onepage&q&f=false]. *[[s:Author:John Alexander Hammerton|Hammerton, John Alexander]] (ed). Countries of the World. Published at the Fleetway House. 6 vols. [https://books.google.co.uk/books?id=e6IaAQAAMAAJ] [https://books.google.co.uk/books?id=K5oaAQAAMAAJ] *[[s:Author:Robert Brown (1842-1895)|Brown, Robert]]. The Countries of the World. [https://books.google.co.uk/books?id=nO0DAAAAQAAJ&pg=PP13#v=onepage&q&f=false] *A Morely Dell. The Countries of the World. (Harrap's New Geographical Series). 1932. (School certificate). Reviews: [https://books.google.co.uk/books?id=oSS9PB_Jf7AC] [https://books.google.co.uk/books?id=BicVAAAAIAAJ] [https://books.google.co.uk/books?id=5qBOAAAAIAAJ] [https://books.google.co.uk/books?id=YbwcAQAAIAAJ] [https://books.google.co.uk/books?id=sc1AAAAAIAAJ] General series: *National Geographic Countries of the World [https://books.google.co.uk/books?id=IT2wfzVIPykC] *Countries of the World. Evans Brothers. (GCSE) [https://books.google.co.uk/books?id=a3sZvWc7E1EC&pg=PA1#v=onepage&q&f=false] *One Europe. Longman. [https://search.worldcat.org/en/title/west-germany-adapted-by-lj-russon-from-the-original-german-by-sylvia-lof-ingrid-mallberg-dietrich-rosenthal/oclc/561591761] *Collier's Nations of the World. The Nations of the World: An Historical Series. [https://books.google.co.uk/books?id=VJY-AAAAYAAJ&pg=PP8#v=onepage&q&f=false] *Collier's History of Nations. The History of Nations. [https://books.google.co.uk/books?id=fmSUfTY5E80C] *The Story of the Nations. T Fisher Unwin. *The World and Its Peoples. (The Illustrated Library of the World and Its Peoples). Greystone Press, New York. *World and Its Peoples. Marshall Cavendish. [https://books.google.co.uk/books?id=oms5xjI7ba0C&pg=PA141#v=onepage&q&f=false] ==England== ===Counties=== See [[s:Portal:Counties]] * Harrison, "County Bibliography" (1886) 3 Library Chronicle [https://books.google.co.uk/books?id=Wz9FAAAAYAAJ&pg=PA49#v=onepage&q&f=false 49] General series *Victoria County History *Oxford County Histories *Pinnock's County Histories *Shire County Guides. Shire Publications. *Cambridge County Geographies *Pike's New Century Series *[[s:Page:County Churches of Cornwall.djvu/6|County Churches]]. G Allen. Avon *Moore. Avon Local History Handbook. Phillimore. 1979. [https://books.google.co.uk/books?id=h0kjAAAAMAAJ] Bibliography, p 102 Bedfordshire *Conisbee, Lewis Ralph. A Bedfordshire Bibliography. Bedfordshire Historical Record Society. Bedford. 1962. Supplements 1967, 1971, 1978. Third supplement by Threadgill. Review: 6 Archives 52 [https://books.google.co.uk/books?id=oOMZAAAAYAAJ]. See also [https://books.google.co.uk/books?id=MjspAAAAYAAJ] [https://books.google.co.uk/books?id=PejgAAAAMAAJ] *Godber. History of Bedfordshire. 1969. 1984. [https://books.google.co.uk/books?id=jdvwPQAACAAJ] *Pinnock. The History and Topography of Bedfordshire [https://books.google.co.uk/books?id=9bJYAAAAcAAJ&pg=PR3#v=onepage&q&f=false] *Parry. Select Illustrations, Historical and Topographical, of Bedfordshire [https://books.google.co.uk/books?id=UTUJAAAAQAAJ&pg=PP7#v=onepage&q&f=false] *Blyth. The History of Bedford and Visitor's Guide. 1873 [https://books.google.co.uk/books?id=IuIGAAAAQAAJ&pg=PP5#v=onepage&q&f=false] *Cambridge County Geographies [https://books.google.co.uk/books?id=kTc8AAAAIAAJ&pg=PP1#v=onepage&q&f=false] Buckinghamshire *Reed. A History of Buckinghamshire. 1993 [https://books.google.co.uk/books?id=BtkWAQAAIAAJ] Cambridgeshire *Carter. History of the County of Cambridge [https://books.google.co.uk/books?id=jXpbAAAAQAAJ&pg=PR3#v=onepage&q&f=false] *Babington. Ancient Cambridgeshire [https://books.google.co.uk/books?id=DPrCAwAAQBAJ&pg=PP1#v=onepage&q&f=false] Devon *Ravenhill and Rowe. Devon Maps and Map-makers [https://books.google.co.uk/books?id=tjf2yAEACAAJ] *Wright. A Plea for a Devonshire Bibliography. 1885 [https://books.google.co.uk/books?id=8ZUDAAAAQAAJ] Derbyshire *Woore. A Catalogue of Local Maps of Derbyshire, C.1528-1800. 2012. [https://books.google.co.uk/books?id=oWmCMwEACAAJ] *O'Neal. A Bibliography of Derbyshire Lead Mining. 1961 Essex *Cunnington. Catalogue of Books, Maps and Manuscripts, relating to or connected with the County of Essex. 1902 [https://books.google.co.uk/books?id=oIcqpibGE4MC] *"The Bibliography of Essex" (1882) 1 Antiquarian Magazine & Bibliographer [https://books.google.co.uk/books?id=dEkEAAAAQAAJ&pg=PA72#v=onepage&q&f=false 72]. See also [https://books.google.co.uk/books?id=dEkEAAAAQAAJ&pg=PA283#v=onepage&q&f=false p 283]. *"The Bibliography of Essex" (1891) 5 The Essex Naturalist 30 [https://books.google.co.uk/books?id=iIo1AQAAMAAJ] *Moon. Essex Literature. 1900. Review: 61 Literary World 438 [https://books.google.co.uk/books?id=2T0ZAAAAYAAJ] See also [https://books.google.co.uk/books?id=1Y4UAQAAIAAJ] [https://books.google.co.uk/books?id=C_pEAAAAMAAJ] *Fenn and Lowery, "An Essex Bibliography", Journal of the South West Essex Technical College, vols 2 & 3 *Victoria County History bibliography. 1959 [https://books.google.co.uk/books?id=F2EJAQAAIAAJ] *O'Leary, John Gerard. A Supplement to the Essex Bibliography. Dagenham. 1962. *A Bibliography of Essex Archaeology & History *Essex and Dagenham: A Catalogue of Books, Pamphlets and Maps. Dagenham. 1961 *Essex Archaeology and History: The Transactions of the Essex Society for Archaeological and History [https://books.google.co.uk/books?id=CtFAAAAAYAAJ] *Essex Naturalist: Being the Journal of the Essex Field Club *Wright. The History and Topography of the County of Essex [https://books.google.co.uk/books?id=SgQVAAAAQAAJ&pg=PP9#v=onepage&q&f=false] *Ogborne, The History of Essex [https://books.google.co.uk/books?id=IeVSAAAAcAAJ&pg=PP5#v=onepage&q&f=false] *Suckling. Memorials of the Antiquities and Architecture, Family History and Heraldry of the County of Essex [https://books.google.co.uk/books?id=bcw_AAAAcAAJ&pg=PP7#v=onepage&q&f=false] *Hunter, The Essex Landscape: A Study of Its Form and History [https://books.google.co.uk/books?id=w9kWAQAAIAAJ] *Cambridge County Geography [https://books.google.co.uk/books?id=GPHa_X_0qo0C&pg=PR3#v=onepage&q&f=false] *Sokoll. Essex  Pauper Letters, 1731-1837 [https://books.google.co.uk/books?id=rCLia7XlqtMC&pg=PP1#v=onepage&q&f=false] *Morant. The History and Antiquities of Colchester in the County of Essex [https://books.google.co.uk/books?id=DDgtAAAAYAAJ&pg=PP9#v=onepage&q&f=false] *Wallen. The History and Antiquities of the Round Church at Little Maplestead, Essex [https://books.google.co.uk/books?id=FPYVAAAAYAAJ&pg=PR1#v=onepage&q&f=false] Kent *Smith. Bibliotheca Cantiana. 1837. [https://books.google.co.uk/books?id=1dJDAAAAYAAJ&pg=PP11#v=onepage&q&f=false] Leicestershire *Kirkby, C V (compiler). Catalogue of the books, pamphlets, &c., relating to Leicestershire in the Central Reference Library. Leicester Free Public Libraries. 1893. Reviews: [https://books.google.co.uk/books?id=3boqAQAAIAAJ&pg=PA84#v=onepage&q&f=false] [https://books.google.co.uk/books?id=UcHnAAAAMAAJ&pg=PA728#v=onepage&q&f=false] *Leicestershire and Rutland Bibliography, 1963-65 (1966) [https://books.google.co.uk/books?id=-OhVAAAAYAAJ 40] Leicestershire Archaeological and Historical Society: Transactions (1964/5) 92. Available as pdf from University of Leicester. *Leicestershire and Rutland Bibliography, 1961-63. Available as pdf from University of Leicester. *Leicestershire and Rutland Bibliography, 1960-61. Available as pdf from University of Leicester. *A Bibliography of the Small Towns in Leicestershire and Rutland, 1600–1850. (Dissertation). [https://repository.lboro.ac.uk/articles/educational_resource/A_bibliography_of_the_small_towns_in_Leicestershire_and_Rutland_1600_1850/9414200] *Loughborough's Heritage: A Bibliography of the Holdings of Leicestershire Libraries and Information Service and Record Office. [https://books.google.co.uk/books?id=Bwx2zgEACAAJ] *Keith Ambrose and Frank Williams, "Bibliography of the Geology of Leicestershire and Rutland: Part 2: 1971-2003" (2004) [https://books.google.co.uk/books?id=U-tQAQAAIAAJ 16] The Mercian Geologist 5. Available as pdf from East Midlands Geological Society. *Parsons and Brandwood. A Bibliography of Leicestershire Churches. 1978. *Education in Leicestershire: A Bibliography. [https://books.google.co.uk/books?id=X6EfzQEACAAJ] Sussex *Brent, Fletcher and McCann. Sussex in the 16th and 17th Centuries: A Bibliography. 2nd Ed [https://books.google.co.uk/books?id=I7UtAAAAYAAJ] *Farrant. Sussex in the 18th and 19th Centuries: A Bibliography. 1st Ed: 1973, 2nd Ed: 1977 [https://books.google.co.uk/books?id=MLUtAAAAYAAJ], 3rd Ed: 1979 ==France== Bibliography: *Bibliographie de la France. Commentary: Encyclopedia of Library and Information Science, vol 37, supplement 2, [https://books.google.co.uk/books?id=10rgjNvOV8oC&pg=PA145#v=onepage&q&f=false p 145]; The Bookseller, 6 January 1881, [https://books.google.co.uk/books?id=4dsiAQAAMAAJ&pg=PA10#v=onepage&q&f=false p 10]; Stein, Manuel de bibliographie générale, [https://books.google.co.uk/books?id=lJYPyKjV1qYC&pg=PA23#v=onepage&q&f=false p 23]. *Girault de Saint-Fargeau. Bibliographie historique et topographique de la France. 1845 [https://books.google.co.uk/books?id=kClB9CQNZoMC&pg=PP9#v=onepage&q&f=false] *Catalogue d'une collection d'ouvrages sur l'histoire des provinces de la France. 1842 [https://books.google.co.uk/books?id=qQBX5WZouzAC&pg=PP1#v=onepage&q&f=false] Landscape: *Beaujeu-Garnier. France. (The World's Landscapes). 1975. [https://books.google.com/books?id=nwxDAQAAIAAJ] Agenais: *Andrieu. Bibliographie générale de l’Agenais et des parties du Condomois et du Bazadais. 1886 to 1891. Reprinted 1969. Alsace: *Ristelhuber. Bibliographie alsacienne. 1869 to 1873 [https://books.google.co.uk/books?id=0mhLAQAAMAAJ&pg=PP13#v=onepage&q&f=false] *Bibliographie alsacienne: Revue critique des publications concernant l'Alsace. 1918 to 1936 *Ritter. Répertoire bibliographique des livres imprimés en Alsace aux XVe et XVIe siècles [https://books.google.co.uk/books?id=DewaAQAAMAAJ] Angoumois: *Castaigne. Essai d'une bibliothèque historique de l'Angoumois, ou Catalogue raisonné des principaux ouvrages qui traitent des différentes branches de l'histoire de cette province. 1847 [https://books.google.co.uk/books?id=R-UanmmlvAEC&pg=PP7#v=onepage&q&f=false] Anjou: *Braguier and Braguier. Archéologie en Anjou: bibliographie. 1984 [https://books.google.co.uk/books?id=LvsmAQAAIAAJ] Auvergne: *Gonot. Catalogue des ouvrages imprimés et manuscrits concernant l'Auvergne, extrait du catalogue général de la Bibliotlèque de Clermont-Fd (Puy-de-Dome). 1849. [https://books.google.co.uk/books?id=yCFtbObRCbUC&pg=PP13#v=onepage&q&f=false] *Catalogue des livres et estampes concernant l'ancienne Province d'Auvergne (Puy-de-Dôme, Cantal, Haute-Loire) réunis par feu M. G. Desbouis. 1865. [https://books.google.co.uk/books?id=Ui4S8_D0N74C&pg=PP7#v=onepage&q&f=false] Béarn *"Bibliographie Béarnaise", Revue de Pau et du Béarn [https://books.google.co.uk/books?id=FuZnAAAAMAAJ] Commentary: [https://books.google.co.uk/books?id=FQYqvPo9D9IC&pg=PA158#v=onepage&q&f=false] [https://books.google.co.uk/books?id=RL9VAAAAYAAJ] Brittany *Sacher. Bibliographie de la Bretagne, ou Catalogue général des ouvrages historiques, littéraires et scientifiques parus sur la Bretagne, avec la liste des revues publiées en cette province, les prix approximatifs des volumes rares, etc. 1881 [https://archive.org/details/bibliographiede00sach] Burgundy: *Milsand. Bibliographie bourguignonne; ou, Catalogue méthodique d'ouvrages relatifs à la Bourgogne: Sciences - Arts - Histoire. 1885 [https://archive.org/details/bibliographiebo00milsgoog] [https://archive.org/details/bibliographiebo00sciegoog] [https://books.google.co.uk/books?id=CxIIAAAAQAAJ] *Catalogue des manuscrits de la Bibliothèque royale des ducs de Bourgogne. 1842 [https://books.google.co.uk/books?id=FX5MAAAAcAAJ&pg=PR3#v=onepage&q&f=false] *The Companion Guide to Burgundy [https://books.google.co.uk/books?id=NraRP0AkDT0C&pg=PP3#v=onepage&q&f=false] *Lecat. The Golden Book of Burgundy. (The Golden Book) [https://books.google.co.uk/books?id=FyzR9qU1Zl4C&lpg=PP1&pg=PP1#v=onepage&q&f=false] *Gwynn. Burgundy: With Chapters on the Jura and Savoy. (Kitbag Travel Books). 1935 [https://books.google.co.uk/books?id=ny1LAAAAMAAJ] *Bazin. Wonderful Burgundy. 1988. 1997 [https://books.google.co.uk/books?id=Yt1CRdICWCUC] *Bailey. Burgundy. (Insight Guides). 1993 [https://books.google.co.uk/books?id=Q69a1dMW2NQC] *Dunlop. Burgundy. Hamilton.1990 [https://books.google.co.uk/books?id=S_1OAAAAMAAJ] Champagne: *Lhermitte. Ouvrages sur la Champagne: contribution à la bibliographie champenoise. 1992. [https://books.google.co.uk/books?id=jbPfAAAAMAAJ] Dauphiné: *Mélanges biographiques et bibliographiques relatifs à l'histoire littéraire du Dauphiné par Colomb de Batines et Ollivier Jules. 1837 [https://books.google.co.uk/books?id=2F5MAAAAcAAJ&pg=PR3#v=onepage&q&f=false] Lorraine: *Bibliographie lorraine. Académie nationale de Metz [https://books.google.co.uk/books?id=n-DfAAAAMAAJ] Maine: *Desportes. Bibliographie du Maine, précédée de la description topographique et hydrographique du diocése du Mans, Sarthe et Mayenne. 1844. [https://books.google.co.uk/books?id=hSk-AAAAYAAJ&pg=PR3#v=onepage&q&f=false] Normandy: *Frère. Manuel du bibliographe Normand ou dictionnaire bibliographique et historique. 1858 to 1860. [https://books.google.co.uk/books?id=dp6geJClg1YC&pg=PP13#v=onepage&q&f=false vol 1] ==Japan== Bibliography and literature *Hideo Kaneko. "Japanese Literature and Bibliography". Kent, Lancour and Daily (eds). Encyclopedia of Library and Information Science. Marcel Dekker. 1977. vol 21. pp [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA131#v=onepage&q&f=false 131] to 176. Bibliography *Jozef Rogala. A Collector's Guide to Books on Japan in English: An Annotated List of Over 2500 Titles with Subject Index. 2001. [https://books.google.co.uk/books?id=7KI9ao-w2FEC&pg=PP1#v=onepage&q&f=false] *Ria Koopmans-de Bruijn. Area Bibliography of Japan. (Scarecrow Area Bibliographies). Scarecrow Press. 1998. [https://books.google.co.uk/books?id=Hlx2OMjgUi0C&pg=PR1#v=onepage&q&f=false] *Frank Joseph Shulman. Japan. (World Bibliographical Series, vol 103). Clio Press. 1989. [https://books.google.co.uk/books?id=LsoUAQAAIAAJ] *Eibun Nihon Kankei Tosho Mokuroku, 1945-1981. (Japanese: 英文日本関係図書目録, 1945-1981). (English: Catalogue of Books in English on Japan, 1945-1981). Japan Foundation. Tokyo. 1986. *Japan: analytical bibliography: with supplementary research aids: and selected data on Okinawa . . . Department of the Army. Washington. 1972. [https://books.google.co.uk/books?id=h4d4nYxrxtMC&pg=PP7#v=onepage&q&f=false] *Books on Japan in Western Languages. The International Christian University Library. 1971. [https://books.google.co.uk/books?id=F2bQAAAAMAAJ] *Books on Japan: A List of Acquisitions, 1955-1970. International House of Japan Library. 1971. [https://books.google.co.uk/books?id=F8sWAQAAIAAJ] *Fukuda. Union Catalog of Books on Japan in Western Languages. 1968. [https://books.google.co.uk/books?id=HKYyAQAAIAAJ] *A Classified List of Books in Western Languages Relating to Japan. University of Tokyo Press. 1965. [https://books.google.co.uk/books?id=U8MUAQAAIAAJ] *Katsuji Yabuki (ed). Japan Bibliographic Annual. Published by the Hokuseido Press for the Japan Writers Society. 1956 and 1957. **Japan Bibliographic Annual 1956. [https://books.google.co.uk/books?id=9XLQAAAAMAAJ] **Japan Bibliographic Annual 1957. [https://books.google.co.uk/books?id=vesSAAAAIAAJ]. Reviews: (1957) 13 Monumenta Nipponica 166 (April-July) [https://books.google.co.uk/books?id=8S1yb-iwrOwC] (1957) 25 The Oriental Economist 212 (April) [https://books.google.co.uk/books?id=QELoAAAAMAAJ] *Haring. Books on Japan: A Reference List. 1955. [https://books.google.co.uk/books?id=RbDoAAAAMAAJ] *Borton. A Selected List of Books and Articles on Japan in English, French, and German. 1940: [https://books.google.co.uk/books?id=YYIsAAAAYAAJ]. Revised and enlarged. Harvard University Press. 1954: [https://books.google.co.uk/books?id=F8O2VwJUPUkC]. **A Selected List of Books on Japan in Western Languages (1945-1960). (Studies on Asia Abroad, vol 1). The Information Centre of Asian Studies, The Toyo Bunko. 1964. [https://books.google.co.uk/books?id=i1_QAAAAMAAJ] *Oskar Nachod. Bibliography of the Japanese Empire 1906-1926. 1928. [https://archive.org/details/bibliographyofja0001oska/page/n8/mode/1up vol 1]. [https://archive.org/details/bibliographyofja0002oska/page/n6/mode/1up vol 2]. *Fr. von Wenckstern. A Bibliography of the Japanese Empire: being a Classified List of All Books, Essays and Maps in European Languages relating to Dai Nihon (Great Japan) published in Europe, America and in the East from 1859-93 . . . 1895. vol 1. [https://books.google.co.uk/books?id=dcVAAAAAYAAJ&pg=PR1#v=onepage&q&f=false] [https://books.google.co.uk/books?id=v7lO4ddqDywC&pg=PR3#v=onepage&q&f=false] **Volume 2, from 1894 to the middle of 1906. 1907. [https://archive.org/details/bibliographyofja0002frvo/page/n6/mode/1up] *Hyman Kublin. What Shall I Read on Japan? An Introductory Guide. Japan Society, New York. 1971. [https://books.google.co.uk/books?id=yRRUAAAAYAAJ] *Henri Cordier. Bibliotheca Japonica: Dictionnaire Bibliographique des Ouvrages Relatifs a L'Empire Japonais. 1912. [https://archive.org/details/bibliothecajapon0008henr/page/n8/mode/1up] Japanese studies *An Introductory Bibliography for Japanese Studies. The Japan Foundation. [https://books.google.co.uk/books?id=53O6AAAAIAAJ] *Richard Perren. Japanese Studies from Pre-History to 1990: A Bibliographical Guide. 1992. [https://books.google.co.uk/books?id=CN9RAQAAIAAJ&pg=PP1#v=onepage&q&f=false]. "Bibliographies" at pp 1 to 3. *K.B.S. Bibliography of Standard Reference Books for Japanese Studies, with Descriptive Notes. University of Tokyo Press. [https://books.google.co.uk/books?id=95wbAAAAMAAJ] *[[w:en:Monumenta Nipponica|Monumenta Nipponica]] *[[w:en:Japan Forum|Japan Forum]]. British Association for Japanese Studies. [https://www.tandfonline.com/journals/rjfo20] *Japanese Studies. Japanese Studies Association of Australia. ISSN 1037-1397. [https://www.tandfonline.com/journals/cjst20] *[[w:en:The Journal of Japanese Studies|The Journal of Japanese Studies]]. University of California Press. *Nichibunken Newsletter. [[w:en:International Research Center for Japanese Studies|International Research Center for Japanese Studies]]. [https://books.google.co.uk/books?id=5TnjAAAAMAAJ] [https://www.nichibun.ac.jp/en/publications/data/news/] [https://newsletter.nichibun.ac.jp/en/] History and culture *John W Dower. Japanese History & Culture from Ancient to Modern Times: Seven Basic Bibliographies. 1986. [https://books.google.co.uk/books?id=NX67AAAAIAAJ&pg=PP1#v=onepage&q&f=false]. "Bibliographies & Research Guides" at chapter 6. Research guides *Mindy L Kotler. Information Gathering on Japan: A Primer. Search Associates. 1988. ISBN 9780962546006. Catalogue: [https://search.worldcat.org/zh-cn/title/Information-gathering-on-Japan-Joho-:-a-primer/oclc/20530148]. Review: (1989) [https://books.google.co.uk/books?id=NZLiAAAAMAAJ 27] Choice 82 Encyclopedias See also [[w:ja:Japanese encyclopedias]] *Louis Frédéric. [[w:Japan Encyclopedia|Japan Encyclopedia]]. Translated by Käthe Roth. 2002. [https://books.google.co.uk/books?id=p2QnPijAEmEC&pg=PP1#v=onepage&q&f=false] **Louis Frédéric. Le Japon: Dictionnaire et Civilisation. Robert Lafont. Paris. 1996. ISBN 2-221-06764-9. *Japan: An Illustrated Encyclopedia. Kodansha. 1993. **Japan: Profile of a Nation. Kodansha. 1995. Revised Edition. 1999. *[[w:Kodansha Encyclopedia of Japan|Kodansha Encyclopedia of Japan]]. 1983. Supplement. 1986. [https://books.google.co.uk/books?id=WvApAQAAMAAJ] *Dorothy Perkins. Encyclopedia of Japan: Japanese History and Culture, from Abacus to Zori. Facts on File. A Roundtable Press Book. 1991. [https://books.google.co.uk/books?id=JLKGAAAAIAAJ] *Pictorial Encyclopedia of Modern Japan. Gakken. 1986. [https://books.google.co.uk/books?id=0FgKAQAAIAAJ] *Boye Layfayette De Mente. Japan Encyclopedia. 1995. [https://books.google.co.uk/books?id=f9c7AAAAMAAJ] **Boye De Mente. Everything Japanese. [The Authoritave Reference on Japan Today]. 1989. [https://books.google.co.uk/books?id=Duku89bARgoC] Biographical dictionaries *Wispelway. Japanese Biographical Index [https://books.google.co.uk/books?id=4UkhAAAAQBAJ&pg=PR3#v=onepage&q&f=false] *Seiichi Iwao. Biographical Dictionary of Japanese History. Kodansha International. 1978.[https://books.google.co.uk/books?id=TkQOAQAAMAAJ] *Senʼichi Hisamatsu. Biographical Dictionary of Japanese Literature. Kodansha International. 1976. [https://books.google.com/books?id=X3lkAAAAMAAJ] *Yutaka Tazawa (ed). Biographical Dictionary of Japanese Art. Kodansha International. 1981. [https://books.google.com/books?id=7ozrAAAAMAAJ] *Japan Biographical Encyclopedia & Who's Who. 1958. Review: [https://books.google.co.uk/books?id=lV_VAAAAMAAJ 25] Contemporary Japan 280 **Japan Biographical Encyclopedia & Who's Who (2nd Edition) 1961. The Japan Biographical Research Department, The Rengo Press Ltd. Preface dated October 1960. Commentary: [https://books.google.co.uk/books?id=-SZSAAAAMAAJ] ***1961 Supplement. December 1961. *Shunjiro Kurita. [[w:ja:Who's Who in Japan|Who's Who in Japan]]. [https://archive.org/details/WhosWhoInJapan1913/page/n24/mode/1up 2nd Ed]. Catalogue: [https://cir.nii.ac.jp/crid/1971712334741056302]. **[[w:ja:石川安次郎|Yasujiro Ishikawa]] (ed). Fifth Annual Edition. The Who's Who in Japan Publishing Department: The Keiseisha. No 15, 2-chome, Owari-cho, Ginza, Kyobashi-ku, Tokyo. Preface dated May 1916. [https://books.google.co.uk/books?id=joBJAAAAYAAJ]. Yasujiro Ishikawa's biography "Ishikawa Yasujiro" is on p 213. *Who's Who in Japan 1984/85. International Culture Institute. Hong Kong. [https://books.google.co.uk/books?id=5a0MAQAAMAAJ]. Reviews: [https://books.google.co.uk/books?id=_xVnAAAAMAAJ 16(2)] World Affairs Report col 349; The Journal of the American Chamber of Commerce in Japan, [https://books.google.co.uk/books?id=Aa62AAAAIAAJ November 1984], p 71. Reference books *Nihon No Sanko Tosho. Volume 1: 1965. Volume 2: 1972. **Guide to Japanese Reference Books. American Library Association. Chicago. 1966: [https://books.google.co.uk/books?id=0rflAAAAMAAJ]. Supplement. 1979: [https://books.google.co.uk/books?id=j05_F9OHzkQC]. Commentary: Encyclopedia of Library and Information Science, vol 21, [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA149#v=onepage&q&f=false p 149]. Media *[https://www.bbc.com/news/world-asia-pacific-15217593 Japan media guide]. News. BBC. 20 March 2023. *Masaaki Kasagi. Mass Media in Japan. (Orientation seminars on Japan, number 14). 1983. [https://books.google.co.uk/books?id=odkgAAAAIAAJ] *Routledge Handbook of Japanese Media [https://books.google.co.uk/books?id=zilKDwAAQBAJ&pg=PA1#v=onepage&q&f=false] Publishers *[https://www.publishersweekly.com/pw/by-topic/international/international-book-news/article/99729-get-to-know-these-japanese-publishing-companies.html Get to Know These Japanese Publishing Companies]. Publishers Weekly. 20 February 2026. Press and journalism *[https://reutersinstitute.politics.ox.ac.uk/digital-news-report/2025/japan Japan]. Reuters Institute for the Study of Journalism. 17 June 2025. *Marjane Aalam and Philippe Régnier. The Japanese Press and Information System. The Graduate Institute of International Studies. Geneva. [https://books.google.co.uk/books?id=RTcbAQAAIAAJ] *The Japanese Press: Past and Present. Japan Newspaper Publishers' and Editors' Association. [https://books.google.co.uk/books?id=5tcQAAAAIAAJ 1949]. *Anthony Rausch. Japanese Journalism and the Japanese Newspaper: A Supplemental Reader. [https://books.google.co.uk/books?id=mZrToQEACAAJ] *Frank L Martin. The Journalism of Japan. 1918. [https://books.google.com/books?id=ruYzAQAAMAAJ] *William De Lange. A History of Japanese Journalism. Japan Library. 1998. [https://books.google.co.uk/books?id=Rd5tb0cuz8QC&pg=PP1#v=onepage&q&f=false] *Kanesada Hanazono. The Development of Japanese Journalism. Osaka. 1924. [https://books.google.co.uk/books?id=z99ZAAAAMAAJ] *Kanesada Hanazono. Journalism in Japan and Its Early Pioneers. 1926. [https://books.google.co.uk/books?id=IGTFfLc4bq0C] *César Castellvi. A Sociology of Journalism in Japan: The Last Empire of the Press. 2024. [https://books.google.co.uk/books?id=a2z8EAAAQBAJ&pg=PR4#v=onepage&q&f=false] *"Japan". Christopher H Sterling (ed). Encyclopedia of Journalism. A Sage Reference Publication. 2009. ISBN 9780761929574. vol 3. pp [https://books.google.co.uk/books?id=ZQhDq8fPj2IC&pg=PA809#v=onepage&q&f=false 809] to 815. Press annuals *The Japanese Press. (Nihon Shinbun Kyokai). [https://books.google.co.uk/books?id=AfvyAAAAMAAJ 1979] [https://books.google.co.uk/books?id=Au3yAAAAMAAJ 1998] Summaries of the press *Daily Summary of Japanese Press Foreign correspondents *Foreign Correspondents in Japan: Reporting a Half Century of Upheavals, from 1945 to the Present. Tuttle. 1998. [https://books.google.co.uk/books?id=YI3TAgAAQBAJ&pg=PP1#v=onepage&q&f=false] Periodicals *G Raymond Nunn (comp). Japanese Periodicals and Newspapers in Western Languages: An International Union List. Mansell. 1979. [https://books.google.co.uk/books?id=jEROAQAAIAAJ] *Japan Periodicals. Keizai Koho Center. 3rd Ed [https://books.google.co.uk/books?id=ATm0AAAAIAAJ]. Japan Periodicals, 1982. [https://books.google.co.uk/books?id=PkMyAAAAMAAJ] *Japanese Periodicals Index **Humanities and Social Sciences [https://books.google.co.uk/books?id=nXX_RpPGf3AC] **Natural Sciences [https://books.google.co.uk/books?id=FCJIAAAAYAAJ] *Current Japanese Periodicals [https://books.google.co.uk/books?id=FjO5AAAAIAAJ] *Check-list of Japanese Periodicals Held in British University and Research Libraries. [https://books.google.co.uk/books?id=VZgsAAAAYAAJ] *Union List of Current Japanese Periodicals in the East Asian Libraries of Columbia, Harvard, Princeton, and Yale Universities. [https://books.google.co.uk/books?id=yw7kAAAAMAAJ] *List of Japanese Periodicals in the Library of the School of Oriental & African Studies. [https://books.google.co.uk/books?id=RREjAQAAIAAJ] *Gianni Simone. [https://www.japantimes.co.jp/community/2011/04/26/issues/english-mags-approach-milestone-crossroads/ English mags approach milestone, crossroads]. The Japan Times. 26 April 2011. *Japan Report (1955 onwards) (Consulate General of Japan, Japan Information Center). Vol 39 published in 1993. [https://books.google.co.uk/books?id=MX4BN_frv4IC&pg=PP7#v=onepage&q&f=false] editions:jYuMSMIQC-AC **Japan Information *Japan Now [https://books.google.co.uk/books?id=Nul7DRQaexMC&pg=PP7#v=onepage&q&f=false] *Japan Quarterly. (Asahi Shimbun). 1954 to 2001. [https://books.google.co.uk/books?id=nZMMAQAAMAAJ] [https://books.google.co.uk/books?id=_RwVAAAAMAAJ] 189 issues. *Japan Illustrated: The Japan Times Quarterly [Pictorial] Magazine (October 1963 to Summer 1977) 15 vols [https://books.google.co.uk/books?id=D7UThOmE8T4C] *[[w:Japan Spotlight|Japan Spotlight]]. Economy, Culture & History: Japan Spotlight: Bimonthly. [https://books.google.co.uk/books?id=i7C0AAAAIAAJ] *Focus Japan. (Japan External Trade Organization, JETRO). [https://books.google.co.uk/books?id=2fG2hsEZpRkC] *The Japan Journal [https://books.google.co.uk/books?id=2V3hAAAAMAAJ] [https://books.google.co.uk/books?id=CJwoAQAAMAAJ] *Japan Magazine. Muromachi Publicity Corporation. (vols 1 to 5: 1957 to 1963). [https://books.google.co.uk/books?id=Swd18PnVeUgC] *The Japan Magazine: A Representative Monthly of Things Japanese [https://books.google.co.uk/books?id=ubGKo-p6O_0C] [https://archive.org/details/jm-1914-v4.9-5.2/mode/1up] *Transactions and Proceedings of the Japan Society, London [https://books.google.co.uk/books?id=B75nnph5qHgC&pg=PP5#v=onepage&q&f=false] **Bulletin. [Bulletin of the Japan Society, London.] [https://books.google.co.uk/books?id=Pd9KvyhnpjMC] **The Japan Society of London Bulletin [https://books.google.co.uk/books?id=XxlxAAAAMAAJ] *About Japan. Japan Society, New York. [https://books.google.co.uk/books?id=Nf5OAQAAIAAJ] **News Bulletin [https://archive.org/details/bub_gb_QcA3AQAAIAAJ/page/n2/mode/1up] *[[w:en:Metropolis (free magazine)|Metropolis]] (metropolisjapan.com) *[[w:en:Tokyo Weekender|Tokyo Weekender]] (トーキョー・ウィークエンダー) [https://www.tokyoweekender.com/japan-life/news-and-opinion/nhk-world-features-the-tokyo-weekender-magazine/] *The Japan Gazette [https://books.google.co.uk/books?id=WSopAAAAYAAJ&pg=PA1#v=onepage&q&f=false] *The Tokio Times [https://books.google.co.uk/books?id=UDfiFBu0vB4C&pg=PA1#v=onepage&q&f=false] *[[w:en:Look Japan|Look Japan]]. (Look Japan Ltd). [https://books.google.co.uk/books?id=QnO6AAAAIAAJ]. Commentary: Gale Directory of Publications and Broadcast Media [https://books.google.co.uk/books?id=ve4dAQAAMAAJ] *[[w:en:Japan Echo|Japan Echo]]. 1974 to 2010. [https://books.google.co.uk/books?id=Cmq6AAAAIAAJ] [https://books.google.co.uk/books?id=fpmEPpl-85UC] *PHP Intersect. (Where Japan Meets Asia and the World). PHP Institute. [https://books.google.co.uk/books?id=i74TAQAAMAAJ] **Intersect Japan [https://books.google.co.uk/books?id=sL8TAQAAMAAJ] *Japan Digest [https://books.google.co.uk/books?id=8AcOAQAAMAAJ] *Speaking of Japan [https://books.google.co.uk/books?id=U7S0AAAAIAAJ]. [Speeches.] *The Hansei Zasshi: A Monthly Magazine [https://books.google.co.uk/books?id=6qBhfHZo7Q0C&pg=PP5#v=onepage&q&f=false][https://books.google.co.uk/books?id=dyIsvnYjpwEC&pg=PP6#v=onepage&q&f=false] **The Orient. 1899 onwards [https://books.google.co.uk/books?id=nS1omYYnnd4C&pg=PP5#v=onepage&q&f=false] *Today's Japan. Orient/West Incorporated. [https://books.google.co.uk/books?id=g2ASAAAAMAAJ] *Japan Review: Bulletin of the International Research Center for Japanese Studies. [https://books.google.co.uk/books?id=GggOAQAAMAAJ] *[https://www.bloomberg.com/account/newsletters/next-japan Next Japan]. Bloomberg. *Niponica. [https://books.google.co.uk/books?id=X2scKgfQS5oC] Newspapers See also [[w:List of newspapers in Japan]] *Haruhara Akihiko, "English-language newspapers in Japan" (1994) 41 Japan Quarterly [https://www.proquest.com/openview/8e2b760f2a2fa37ba164ea675c095353/1 474] (Issue 4: October 1994) *James Charles Tanner. English Language Newspapers in Bakumatsu Japan. 1977. [https://books.google.co.uk/books?id=Bn2zgzZy_3oC] *[https://www.japantimes.co.jp/news/2009/03/03/reference/newspapers-here-soldiering-on/ Newspapers here soldiering on]. The Japan Times. 3 March 2009. *[[w:The Japan Times|The Japan Times]] **The Japan Times: Weekly Edition [https://books.google.co.uk/books?id=KoQ-AQAAMAAJ] [https://books.google.co.uk/books?id=yYQ-AQAAMAAJ&pg=PA1#v=onepage&q&f=false] *Japan Daily Mail *Japan Weekly Mail *The Japan Chronicle **Weekly Edition [https://books.google.co.uk/books?id=vXdRAQAAIAAJ&pg=PA1#v=onepage&q&f=false] *The Japan News. (The Japan News by The Yomiuri Shimbun) **Yomiuri Japan News (from 1955) **The Yomiuri (from 1958) **The Daily Yomiuri (from 1970) *The Asahi Shimbun: Asia & Japan Watch. [https://www.asahi.com/sp/ajw/] **Asahi Evening News (from 1954) ***Tokyo Evening News (1952 to 1954) [https://ndlsearch.ndl.go.jp/books/R100000002-I000000145073] *The Mainichi. [https://mainichi.jp/english/] **Mainichi Daily News (1922 to 2001) [https://www.nytimes.com/2001/02/27/business/worldbusiness/IHT-tech-briefstop-the-presses.html] [https://ndlsearch.ndl.go.jp/books/R100000002-I000000144910] Sports newspapers; sports dailies *Louise do Rosario, "News-stand stars" in "Japan" (1992) [https://books.google.co.uk/books?id=T_GzAAAAIAAJ 155] [[w:en:Far Eastern Economic Review|Far Eastern Economic Review]], 24 to 31 December 1992, p 21 *[[w:ja:岡崎満義|Mitsuyoshi Okazaki]], "Unsportsmanlike Journalism: Japan's sports dailies may be popular, but are they sporting?" in "Sport", [[w:en:Look Japan|Look Japan]], [https://books.google.co.uk/books?id=lD3tAAAAMAAJ January 1995], p 39 News *[[w:en:Japan Today|Japan Today]] (ジャパントゥデイ). GPlusMedia. Gakken Holdings. Annuals and year books *This is Japan. Asahi Shimbun. 1954 to 1971. [https://books.google.co.uk/books?id=2X9DAQAAIAAJ]. Commentary: A Victorian Sailor's Grave in the Seto Inland Sea, p 244 [https://books.google.co.uk/books?id=OegkAgAAQBAJ&pg=PA244#v=onepage&q&f=false] *The Japan Year Book. The Japan Year Book Office. 1905 onwards. [https://archive.org/details/bub_gb_arFPAAAAMAAJ/page/n10/mode/1up 1906]. [https://archive.org/details/in.ernet.dli.2015.553496/page/n27/mode/1up 1915]. *The "Japan Gazette" Japan Year Book. The Japan Gazette. [https://archive.org/details/japan-year-book-1913-1914/page/n15/mode/1up 1913-14] *The Japan Times Year Book *New Japan. Mainichi Newspapers. [https://books.google.co.uk/books?id=gRFCAQAAIAAJ] Almanacs *Asahi Shimbun Japan Almanac. [https://books.google.co.uk/books?id=SEEEAQAAIAAJ 1995]. *Japan Almanac. (The Mainichi Newspapers). [https://books.google.co.uk/books?id=ufAIAQAAIAAJ 1972]. [https://books.google.co.uk/books?id=X4eXWRkbtFsC 1973]. [https://books.google.co.uk/books?id=7rMrAAAAIAAJ] [https://books.google.co.uk/books?id=krMrAAAAIAAJ] *[[w:Boyé Lafayette De Mente|Boye De Mente]]. Passport's Japan Almanac. [https://books.google.co.uk/books?id=741wAAAAMAAJ] General *Japan: A Country Study. (Area Handbook series). 4th Ed: 1983: [https://books.google.co.uk/books?id=HkM5N3JNc5IC]. 5th Ed: 1992: [https://books.google.co.uk/books?id=ze-wupXxpvEC] *Area Handbook for Japan. 2nd Ed: 1964: [https://books.google.co.uk/books?id=WucdAAAAMAAJ&pg=PR1#v=onepage&q&f=false]. 3rd Ed: 1974: [https://books.google.co.uk/books?id=LG2aoq1U_eoC&pg=PR1#v=onepage&q&f=false] (DA Pam 550-30). *Colin Simpson. Picture of Japan. **Japan: An Intimate View. A S Barnes. [https://books.google.co.uk/books?id=3hkeAAAAMAAJ] **This is Japan. Angus & Robertson. [https://books.google.co.uk/books?id=HJEJAQAAIAAJ] *Japan. (The World and Its Peoples). Greystone Press, New York. 1964. Volume 1: [https://books.google.co.uk/books?id=yysUAQAAMAAJ]. Volume 2 "Japan Korea", including Korea: [https://books.google.co.uk/books?id=uQAUAQAAMAAJ]. See pp 1 to 375 for Japan, and pp 376 to 379 for Ryukyu and Bonin Islands. *Japan. (World and its Peoples: Eastern and Southern Asia, volume 8). Marshall Cavendish. 2008. ISBN 9780761476412. *Edward Seidensticker. This Country, Japan. Kodansha International. 1979. ISBN 9780870112294. [https://books.google.co.uk/books?id=88wwAQAAIAAJ] *Hall and Beardsley. Twelve Doors to Japan. McGraw-Hill. New York. 1965. [https://books.google.co.uk/books?id=0KpxAAAAMAAJ] *"Japan". Louis Barron (ed). "Asia & Australasia". Moshe Y Sachs (ed and pub). Worldmark Encyclopedia of the Nations. Worldmark Press, Inc. Harper & Row New York. 1963. pp 145 to 160. [https://books.google.co.uk/books?id=I0oYAQAAMAAJ] **"Japan". Asia & Oceania. 7th Ed: 1988. ISBN 0-471 62406-3. vol 4. pp 153 to 168. **"Japan". Asia & Oceania. 8th Ed: 1995. Gale Research Inc. ISBN 0-8103-9882-6. vol 4. pp 203 to 220. *James E Hoare. "Japan". East and Southeast Asia. The World Today Series 2023–2024. pp [https://books.google.co.uk/books?id=3GfQEAAAQBAJ&pg=PA107#v=onepage&q&f=false 107] to 133. *Japan. (Library of Nations). Time Life Books. 1985. ISBN 0809453347. ISBN 0705408485. [https://books.google.co.uk/books?id=P1NJwcWAnboC] [https://books.google.co.uk/books?id=Ui2CvuyM4JkC] Handbooks *Patrick Heenan (ed). The Japan Handbook. (Regional Handbooks of Economic Development). 1998. [https://books.google.co.uk/books?id=IMG2AgAAQBAJ&pg=PP1#v=onepage&q&f=false] Introduction *Introducing Japan Through Books: A Selected Bibliography. Public Information Bureau, Ministry of Foreign Affairs, Japan. 1968. [https://books.google.co.uk/books?id=FvsyAQAAIAAJ]. 2nd Ed: 1973: [https://books.google.co.uk/books?id=Vj0XAQAAMAAJ]. *Donald Ritchie. Introducing Japan. 1st Ed: 1978. Revised Ed: 1986. 6th printing: 1989: [https://books.google.co.uk/books?id=FE-nxxoKayQC]. 2nd Revised Ed: 1990. 2nd printing: 1991: [https://books.google.co.uk/books?id=hz4UAQAAIAAJ]. 1994: [https://books.google.co.uk/books?id=FMvT6m4SgIQC&pg=PP1#v=onepage&q&f=false]. *Herschel Webb. An Introduction to Japan. Columbia University Press. 2nd Ed: 1957: [https://books.google.co.uk/books?id=YQ8MAQAAIAAJ]. *Introducing Modern Japan. A publication of the Japan Information and Culture Center, Embassy of Japan. Today and yesterday *Ray Downs. Japan Yesterday and Today. Praeger Publishers. 1970. [https://books.google.co.uk/books?id=PwKxAAAAIAAJ] Today *Roger Buckley. Japan Today. Cambridge University Press. 3rd Ed [https://books.google.co.uk/books?id=thyqBtJp2DcC&pg=PP1#v=onepage&q&f=false] Contemporary *Routledge Handbook of Contemporary Japan. 2021. [https://books.google.co.uk/books?id=yfH3DwAAQBAJ&pg=PA2011#v=onepage&q&f=false] *Duncan McCargo. Contemporary Japan. 3rd Ed: 2012. [https://books.google.co.uk/books?id=8I5KEAAAQBAJ&pg=PP1#v=onepage&q&f=false] *Jeff Kingston. Contemporary Japan: History, Politics, and Social Change since the 1980s. 2011. [https://books.google.co.uk/books?id=enJQZA3R4FMC&pg=PP1#v=onepage&q&f=false] [Series] *Routledge Contemporary Japan Series Modern *Hugh Cortazzi. Modern Japan: A Concise Survey. Palgrave Macmillan. 1993. [https://books.google.co.uk/books?id=Cf--DAAAQBAJ&pg=PP1#v=onepage&q&f=false] The Japanese *Peter Tasker. The Japanese: Portrait of a Nation. 1989 [https://books.google.com/books?id=Q1N8ld78wwQC] **The Japanese: A Major Exploration of Modern Japan. [https://books.google.co.uk/books?id=CW-6AAAAIAAJ] **Inside Japan: Wealth, Work and Power in the New Japanese Empire. 1987. [https://books.google.co.uk/books?id=2OJuAAAAMAAJ] *Edwin O Reischauer. The Japanese. The Belknap Press of Harvard University Press. [https://books.google.co.uk/books?id=zrEqAAAAYAAJ] *Edwin O Reischauer and Marius B Jansen. The Japanese Today: Change and Continuity. 1995. [https://books.google.co.uk/books?id=BTPNlLIy2soC&pg=PP1#v=onepage&q&f=false] Japaneseness *Ray T. Donahue (ed). Exploring Japaneseness: On Japanese Enactments of Culture and Consciousness. Ablex Publishing. 2002. [https://books.google.co.uk/books?id=V_NwAAAAMAAJ] *Yoji Yamakuse. Japaneseness: A Guide to Values and Virtues. 2016. [https://books.google.co.uk/books?id=tB0iDAAAQBAJ&pg=PP1#v=onepage&q&f=false] Travel books *DK Eyewitness Travel: Japan. Reprinted with revisions. 2015: [https://books.google.co.uk/books?id=g2NaBgAAQBAJ&pg=PP1#v=onepage&q&f=false]. 2017: [https://books.google.co.uk/books?id=vg15DQAAQBAJ&pg=PP1#v=onepage&q&f=false]. *Dodd and Richmond. The Rough Guide to Japan. 2nd Ed: 2001: [https://books.google.co.uk/books?id=pRGq95ytWZoC&pg=PP1#v=onepage&q&f=false]. *Frommer's Japan. 5th Ed: 2000: [https://books.google.co.uk/books?id=-QC8mVyvPa8C]. *Fodor's Japan YYYY. 1984. [https://books.google.co.uk/books?id=aH2Ow27HUQ0C 1986]. [https://books.google.co.uk/books?id=3gTTf6nbv20C 1987]. 1988. **Fodor's YY Japan. [https://books.google.co.uk/books?id=9QMHllzldlYC 91]. 92. 93. **Fodor's Japan. 13th Ed: 1996: [https://books.google.co.uk/books?id=cZxZAAAAYAAJ] *The New Official Guide: Japan. Japan Travel Bureau. 1966. [https://books.google.co.uk/books?id=HoxxAAAAMAAJ] *Here is Japan. Asahi Broadcasting Corporation. [https://books.google.co.uk/books?id=8QXRCTMNG7MC] *Japan. (Nagel Travel Guide Series, vol 32). 1964. [https://books.google.co.uk/books?id=QsbXAAAAMAAJ] *Clark. All the Best in Japan: with Manila, Hong Kong, and Macao. ("All the Best" series). 1959. Reprinted 1964. [https://books.google.co.uk/books?id=yUq4YaaryrwC]. Reviews: [https://archive.dartmouthalumnimagazine.com/article/1958/6/1/all-the-best-in-japan] (1958) 110 Travel 51 [https://books.google.co.uk/books?id=UVwXAQAAMAAJ] 3 Bulletin of the Japan Society, London, No 11: June 1960, p 25 [https://books.google.co.uk/books?id=2oy74hRRXk4C] **All the Best in Japan and the Orient. 1967. Night *[[w:ja:Taizo Fujimoto|Taizo Fujimoto]]. The Nightside of Japan. T Werner Laurie. Essex Street, Strand, London. 1914. [https://archive.org/details/nightsideofjapan00fujirich/page/n6/mode/1up] Exhibitions *Patricia Morison. "Fun and games with Japanese angst". The Financial Times. Weekend 21/22 September 1991. No 31562. Section II: "Weekend FT". Weekend 21/22 September 1991. Page xx. ["Visions of Japan" exhibition, Victoria and Albert Musuem, ending 5 January 1992.] Languages See [[Universal Bibliography/Languages/Japanese|Japanese]] Literature See [[Universal Bibliography/Literature#Japanese|Japanese literature]] Music See [[Universal Bibliography/Music#Japanese and Japan|Music of Japan]] Cinema See [[Universal Bibliography/Cinema#Japanese|Cinema of Japan]] Television See [[Universal Bibliography/Television#Japanese|Japanese television]] Architecture See [[Universal Bibliography/Architecture|Japanese architecture]] Culture See [[Universal Bibliography/Culture#Japanese|Culture of Japan]] Economy *MERI's Monthly Circular: Survey of Economic Conditions in Japan (1923 to 2025) Mitsubishi Economic Research Institute [https://books.google.co.uk/books?id=4QDtAAAAMAAJ] [https://www.meri.or.jp/en/mc.html] Tokyo *J S Eades. Tokyo. (World Bibliographical Series, vol 214). CLIO Press. 1999. ISBN 1-85109-292-7. [https://books.google.co.uk/books?id=TrkUAQAAIAAJ] ==Korea== *Korea Journal [https://books.google.co.uk/books?id=O6XfBexsp6gC] Bibliography and literature *Thomas H Kang. "Korean Literature and Bibliography". Kent, Lancour and Daily (eds). Encyclopedia of Library and Information Science. Marcel Dekker. 1977. vol 21. pp [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA176#v=onepage&q&f=false 176] to 240. [[Category:Countries]] 2qp8gnb71th2s9hujxjh0542frdvj0x 2844887 2844883 2026-11-08T17:33:57Z James500 297601 /* Japan */ Add 2844887 wikitext text/x-wiki {{Bibliography}} See also [[Universal Bibliography/Geography|Geography]]. See [[w:Category:Bibliographies of countries or regions]] and [[w:Category:Works about countries]]. This part of the [[Universal Bibliography]] is a bibliography of countries (including former countries). ==Countries== *Bateman and Egan (eds). The Encyclopedia of World Geography: A Country by Country Guide. 1993. Revised 1997. *Peter Stalker. Handbook of the World. 2000. A Guide to Countries of the World. (Oxford Guide to Countries of the World. 2nd Ed: 2004, 2nd Revised Ed: 2007 [https://books.google.co.uk/books?id=GtztAAAAMAAJ], 3rd Ed: 2010 [https://books.google.co.uk/books?id=gvKvfxkbZ1AC&pg=PP1#v=onepage&q&f=false] *Countries of the World and Their Leaders Yearbook. Gale. [https://books.google.co.uk/books?id=5etKAAAAYAAJ] [https://books.google.co.uk/books?id=p41OAAAAIAAJ] *Hutchinson Guide to Countries of the World [https://books.google.co.uk/books?id=GgpjUe4kN_IC] *The World Guide: Global Reference, Country by Country. 11th Ed: 2007 [https://books.google.co.uk/books?id=EoWoLgAACAAJ] *Spence. The World Today: A Nation-by-Nation Guide. Cassell. 1994. 1999. [https://books.google.com/books?id=Ub8qOQAACAAJ] *Worldmark Encyclopedia of the Nations [https://books.google.co.uk/books?id=I0oYAQAAMAAJ] *Kurian. Encyclopedia of the World's Nations. Facts on File. Reviews: [https://books.google.co.uk/books?id=Y1EnAQAAIAAJ] [https://books.google.co.uk/books?id=lz0RAQAAMAAJ] *Michael O'Mara. Facts about the World's Nations. 1999. [https://books.google.co.uk/books?id=mygYAAAAIAAJ] *Status of the World's Nations. 1965 [https://books.google.co.uk/books?id=sftEyRbAXMUC&pg=PP1#v=onepage&q&f=false]. 1973 [https://books.google.co.uk/books?id=kw2U_Cg2gKYC&pg=PP3#v=onepage&q&f=false]. *[[s:Author:John Alexander Hammerton|Hammerton, John Alexander]] (ed). Countries of the World. Published at the Fleetway House. 6 vols. [https://books.google.co.uk/books?id=e6IaAQAAMAAJ] [https://books.google.co.uk/books?id=K5oaAQAAMAAJ] *[[s:Author:Robert Brown (1842-1895)|Brown, Robert]]. The Countries of the World. [https://books.google.co.uk/books?id=nO0DAAAAQAAJ&pg=PP13#v=onepage&q&f=false] *A Morely Dell. The Countries of the World. (Harrap's New Geographical Series). 1932. (School certificate). Reviews: [https://books.google.co.uk/books?id=oSS9PB_Jf7AC] [https://books.google.co.uk/books?id=BicVAAAAIAAJ] [https://books.google.co.uk/books?id=5qBOAAAAIAAJ] [https://books.google.co.uk/books?id=YbwcAQAAIAAJ] [https://books.google.co.uk/books?id=sc1AAAAAIAAJ] General series: *National Geographic Countries of the World [https://books.google.co.uk/books?id=IT2wfzVIPykC] *Countries of the World. Evans Brothers. (GCSE) [https://books.google.co.uk/books?id=a3sZvWc7E1EC&pg=PA1#v=onepage&q&f=false] *One Europe. Longman. [https://search.worldcat.org/en/title/west-germany-adapted-by-lj-russon-from-the-original-german-by-sylvia-lof-ingrid-mallberg-dietrich-rosenthal/oclc/561591761] *Collier's Nations of the World. The Nations of the World: An Historical Series. [https://books.google.co.uk/books?id=VJY-AAAAYAAJ&pg=PP8#v=onepage&q&f=false] *Collier's History of Nations. The History of Nations. [https://books.google.co.uk/books?id=fmSUfTY5E80C] *The Story of the Nations. T Fisher Unwin. *The World and Its Peoples. (The Illustrated Library of the World and Its Peoples). Greystone Press, New York. *World and Its Peoples. Marshall Cavendish. [https://books.google.co.uk/books?id=oms5xjI7ba0C&pg=PA141#v=onepage&q&f=false] ==England== ===Counties=== See [[s:Portal:Counties]] * Harrison, "County Bibliography" (1886) 3 Library Chronicle [https://books.google.co.uk/books?id=Wz9FAAAAYAAJ&pg=PA49#v=onepage&q&f=false 49] General series *Victoria County History *Oxford County Histories *Pinnock's County Histories *Shire County Guides. Shire Publications. *Cambridge County Geographies *Pike's New Century Series *[[s:Page:County Churches of Cornwall.djvu/6|County Churches]]. G Allen. Avon *Moore. Avon Local History Handbook. Phillimore. 1979. [https://books.google.co.uk/books?id=h0kjAAAAMAAJ] Bibliography, p 102 Bedfordshire *Conisbee, Lewis Ralph. A Bedfordshire Bibliography. Bedfordshire Historical Record Society. Bedford. 1962. Supplements 1967, 1971, 1978. Third supplement by Threadgill. Review: 6 Archives 52 [https://books.google.co.uk/books?id=oOMZAAAAYAAJ]. See also [https://books.google.co.uk/books?id=MjspAAAAYAAJ] [https://books.google.co.uk/books?id=PejgAAAAMAAJ] *Godber. History of Bedfordshire. 1969. 1984. [https://books.google.co.uk/books?id=jdvwPQAACAAJ] *Pinnock. The History and Topography of Bedfordshire [https://books.google.co.uk/books?id=9bJYAAAAcAAJ&pg=PR3#v=onepage&q&f=false] *Parry. Select Illustrations, Historical and Topographical, of Bedfordshire [https://books.google.co.uk/books?id=UTUJAAAAQAAJ&pg=PP7#v=onepage&q&f=false] *Blyth. The History of Bedford and Visitor's Guide. 1873 [https://books.google.co.uk/books?id=IuIGAAAAQAAJ&pg=PP5#v=onepage&q&f=false] *Cambridge County Geographies [https://books.google.co.uk/books?id=kTc8AAAAIAAJ&pg=PP1#v=onepage&q&f=false] Buckinghamshire *Reed. A History of Buckinghamshire. 1993 [https://books.google.co.uk/books?id=BtkWAQAAIAAJ] Cambridgeshire *Carter. History of the County of Cambridge [https://books.google.co.uk/books?id=jXpbAAAAQAAJ&pg=PR3#v=onepage&q&f=false] *Babington. Ancient Cambridgeshire [https://books.google.co.uk/books?id=DPrCAwAAQBAJ&pg=PP1#v=onepage&q&f=false] Devon *Ravenhill and Rowe. Devon Maps and Map-makers [https://books.google.co.uk/books?id=tjf2yAEACAAJ] *Wright. A Plea for a Devonshire Bibliography. 1885 [https://books.google.co.uk/books?id=8ZUDAAAAQAAJ] Derbyshire *Woore. A Catalogue of Local Maps of Derbyshire, C.1528-1800. 2012. [https://books.google.co.uk/books?id=oWmCMwEACAAJ] *O'Neal. A Bibliography of Derbyshire Lead Mining. 1961 Essex *Cunnington. Catalogue of Books, Maps and Manuscripts, relating to or connected with the County of Essex. 1902 [https://books.google.co.uk/books?id=oIcqpibGE4MC] *"The Bibliography of Essex" (1882) 1 Antiquarian Magazine & Bibliographer [https://books.google.co.uk/books?id=dEkEAAAAQAAJ&pg=PA72#v=onepage&q&f=false 72]. See also [https://books.google.co.uk/books?id=dEkEAAAAQAAJ&pg=PA283#v=onepage&q&f=false p 283]. *"The Bibliography of Essex" (1891) 5 The Essex Naturalist 30 [https://books.google.co.uk/books?id=iIo1AQAAMAAJ] *Moon. Essex Literature. 1900. Review: 61 Literary World 438 [https://books.google.co.uk/books?id=2T0ZAAAAYAAJ] See also [https://books.google.co.uk/books?id=1Y4UAQAAIAAJ] [https://books.google.co.uk/books?id=C_pEAAAAMAAJ] *Fenn and Lowery, "An Essex Bibliography", Journal of the South West Essex Technical College, vols 2 & 3 *Victoria County History bibliography. 1959 [https://books.google.co.uk/books?id=F2EJAQAAIAAJ] *O'Leary, John Gerard. A Supplement to the Essex Bibliography. Dagenham. 1962. *A Bibliography of Essex Archaeology & History *Essex and Dagenham: A Catalogue of Books, Pamphlets and Maps. Dagenham. 1961 *Essex Archaeology and History: The Transactions of the Essex Society for Archaeological and History [https://books.google.co.uk/books?id=CtFAAAAAYAAJ] *Essex Naturalist: Being the Journal of the Essex Field Club *Wright. The History and Topography of the County of Essex [https://books.google.co.uk/books?id=SgQVAAAAQAAJ&pg=PP9#v=onepage&q&f=false] *Ogborne, The History of Essex [https://books.google.co.uk/books?id=IeVSAAAAcAAJ&pg=PP5#v=onepage&q&f=false] *Suckling. Memorials of the Antiquities and Architecture, Family History and Heraldry of the County of Essex [https://books.google.co.uk/books?id=bcw_AAAAcAAJ&pg=PP7#v=onepage&q&f=false] *Hunter, The Essex Landscape: A Study of Its Form and History [https://books.google.co.uk/books?id=w9kWAQAAIAAJ] *Cambridge County Geography [https://books.google.co.uk/books?id=GPHa_X_0qo0C&pg=PR3#v=onepage&q&f=false] *Sokoll. Essex  Pauper Letters, 1731-1837 [https://books.google.co.uk/books?id=rCLia7XlqtMC&pg=PP1#v=onepage&q&f=false] *Morant. The History and Antiquities of Colchester in the County of Essex [https://books.google.co.uk/books?id=DDgtAAAAYAAJ&pg=PP9#v=onepage&q&f=false] *Wallen. The History and Antiquities of the Round Church at Little Maplestead, Essex [https://books.google.co.uk/books?id=FPYVAAAAYAAJ&pg=PR1#v=onepage&q&f=false] Kent *Smith. Bibliotheca Cantiana. 1837. [https://books.google.co.uk/books?id=1dJDAAAAYAAJ&pg=PP11#v=onepage&q&f=false] Leicestershire *Kirkby, C V (compiler). Catalogue of the books, pamphlets, &c., relating to Leicestershire in the Central Reference Library. Leicester Free Public Libraries. 1893. Reviews: [https://books.google.co.uk/books?id=3boqAQAAIAAJ&pg=PA84#v=onepage&q&f=false] [https://books.google.co.uk/books?id=UcHnAAAAMAAJ&pg=PA728#v=onepage&q&f=false] *Leicestershire and Rutland Bibliography, 1963-65 (1966) [https://books.google.co.uk/books?id=-OhVAAAAYAAJ 40] Leicestershire Archaeological and Historical Society: Transactions (1964/5) 92. Available as pdf from University of Leicester. *Leicestershire and Rutland Bibliography, 1961-63. Available as pdf from University of Leicester. *Leicestershire and Rutland Bibliography, 1960-61. Available as pdf from University of Leicester. *A Bibliography of the Small Towns in Leicestershire and Rutland, 1600–1850. (Dissertation). [https://repository.lboro.ac.uk/articles/educational_resource/A_bibliography_of_the_small_towns_in_Leicestershire_and_Rutland_1600_1850/9414200] *Loughborough's Heritage: A Bibliography of the Holdings of Leicestershire Libraries and Information Service and Record Office. [https://books.google.co.uk/books?id=Bwx2zgEACAAJ] *Keith Ambrose and Frank Williams, "Bibliography of the Geology of Leicestershire and Rutland: Part 2: 1971-2003" (2004) [https://books.google.co.uk/books?id=U-tQAQAAIAAJ 16] The Mercian Geologist 5. Available as pdf from East Midlands Geological Society. *Parsons and Brandwood. A Bibliography of Leicestershire Churches. 1978. *Education in Leicestershire: A Bibliography. [https://books.google.co.uk/books?id=X6EfzQEACAAJ] Sussex *Brent, Fletcher and McCann. Sussex in the 16th and 17th Centuries: A Bibliography. 2nd Ed [https://books.google.co.uk/books?id=I7UtAAAAYAAJ] *Farrant. Sussex in the 18th and 19th Centuries: A Bibliography. 1st Ed: 1973, 2nd Ed: 1977 [https://books.google.co.uk/books?id=MLUtAAAAYAAJ], 3rd Ed: 1979 ==France== Bibliography: *Bibliographie de la France. Commentary: Encyclopedia of Library and Information Science, vol 37, supplement 2, [https://books.google.co.uk/books?id=10rgjNvOV8oC&pg=PA145#v=onepage&q&f=false p 145]; The Bookseller, 6 January 1881, [https://books.google.co.uk/books?id=4dsiAQAAMAAJ&pg=PA10#v=onepage&q&f=false p 10]; Stein, Manuel de bibliographie générale, [https://books.google.co.uk/books?id=lJYPyKjV1qYC&pg=PA23#v=onepage&q&f=false p 23]. *Girault de Saint-Fargeau. Bibliographie historique et topographique de la France. 1845 [https://books.google.co.uk/books?id=kClB9CQNZoMC&pg=PP9#v=onepage&q&f=false] *Catalogue d'une collection d'ouvrages sur l'histoire des provinces de la France. 1842 [https://books.google.co.uk/books?id=qQBX5WZouzAC&pg=PP1#v=onepage&q&f=false] Landscape: *Beaujeu-Garnier. France. (The World's Landscapes). 1975. [https://books.google.com/books?id=nwxDAQAAIAAJ] Agenais: *Andrieu. Bibliographie générale de l’Agenais et des parties du Condomois et du Bazadais. 1886 to 1891. Reprinted 1969. Alsace: *Ristelhuber. Bibliographie alsacienne. 1869 to 1873 [https://books.google.co.uk/books?id=0mhLAQAAMAAJ&pg=PP13#v=onepage&q&f=false] *Bibliographie alsacienne: Revue critique des publications concernant l'Alsace. 1918 to 1936 *Ritter. Répertoire bibliographique des livres imprimés en Alsace aux XVe et XVIe siècles [https://books.google.co.uk/books?id=DewaAQAAMAAJ] Angoumois: *Castaigne. Essai d'une bibliothèque historique de l'Angoumois, ou Catalogue raisonné des principaux ouvrages qui traitent des différentes branches de l'histoire de cette province. 1847 [https://books.google.co.uk/books?id=R-UanmmlvAEC&pg=PP7#v=onepage&q&f=false] Anjou: *Braguier and Braguier. Archéologie en Anjou: bibliographie. 1984 [https://books.google.co.uk/books?id=LvsmAQAAIAAJ] Auvergne: *Gonot. Catalogue des ouvrages imprimés et manuscrits concernant l'Auvergne, extrait du catalogue général de la Bibliotlèque de Clermont-Fd (Puy-de-Dome). 1849. [https://books.google.co.uk/books?id=yCFtbObRCbUC&pg=PP13#v=onepage&q&f=false] *Catalogue des livres et estampes concernant l'ancienne Province d'Auvergne (Puy-de-Dôme, Cantal, Haute-Loire) réunis par feu M. G. Desbouis. 1865. [https://books.google.co.uk/books?id=Ui4S8_D0N74C&pg=PP7#v=onepage&q&f=false] Béarn *"Bibliographie Béarnaise", Revue de Pau et du Béarn [https://books.google.co.uk/books?id=FuZnAAAAMAAJ] Commentary: [https://books.google.co.uk/books?id=FQYqvPo9D9IC&pg=PA158#v=onepage&q&f=false] [https://books.google.co.uk/books?id=RL9VAAAAYAAJ] Brittany *Sacher. Bibliographie de la Bretagne, ou Catalogue général des ouvrages historiques, littéraires et scientifiques parus sur la Bretagne, avec la liste des revues publiées en cette province, les prix approximatifs des volumes rares, etc. 1881 [https://archive.org/details/bibliographiede00sach] Burgundy: *Milsand. Bibliographie bourguignonne; ou, Catalogue méthodique d'ouvrages relatifs à la Bourgogne: Sciences - Arts - Histoire. 1885 [https://archive.org/details/bibliographiebo00milsgoog] [https://archive.org/details/bibliographiebo00sciegoog] [https://books.google.co.uk/books?id=CxIIAAAAQAAJ] *Catalogue des manuscrits de la Bibliothèque royale des ducs de Bourgogne. 1842 [https://books.google.co.uk/books?id=FX5MAAAAcAAJ&pg=PR3#v=onepage&q&f=false] *The Companion Guide to Burgundy [https://books.google.co.uk/books?id=NraRP0AkDT0C&pg=PP3#v=onepage&q&f=false] *Lecat. The Golden Book of Burgundy. (The Golden Book) [https://books.google.co.uk/books?id=FyzR9qU1Zl4C&lpg=PP1&pg=PP1#v=onepage&q&f=false] *Gwynn. Burgundy: With Chapters on the Jura and Savoy. (Kitbag Travel Books). 1935 [https://books.google.co.uk/books?id=ny1LAAAAMAAJ] *Bazin. Wonderful Burgundy. 1988. 1997 [https://books.google.co.uk/books?id=Yt1CRdICWCUC] *Bailey. Burgundy. (Insight Guides). 1993 [https://books.google.co.uk/books?id=Q69a1dMW2NQC] *Dunlop. Burgundy. Hamilton.1990 [https://books.google.co.uk/books?id=S_1OAAAAMAAJ] Champagne: *Lhermitte. Ouvrages sur la Champagne: contribution à la bibliographie champenoise. 1992. [https://books.google.co.uk/books?id=jbPfAAAAMAAJ] Dauphiné: *Mélanges biographiques et bibliographiques relatifs à l'histoire littéraire du Dauphiné par Colomb de Batines et Ollivier Jules. 1837 [https://books.google.co.uk/books?id=2F5MAAAAcAAJ&pg=PR3#v=onepage&q&f=false] Lorraine: *Bibliographie lorraine. Académie nationale de Metz [https://books.google.co.uk/books?id=n-DfAAAAMAAJ] Maine: *Desportes. Bibliographie du Maine, précédée de la description topographique et hydrographique du diocése du Mans, Sarthe et Mayenne. 1844. [https://books.google.co.uk/books?id=hSk-AAAAYAAJ&pg=PR3#v=onepage&q&f=false] Normandy: *Frère. Manuel du bibliographe Normand ou dictionnaire bibliographique et historique. 1858 to 1860. [https://books.google.co.uk/books?id=dp6geJClg1YC&pg=PP13#v=onepage&q&f=false vol 1] ==Japan== Bibliography and literature *Hideo Kaneko. "Japanese Literature and Bibliography". Kent, Lancour and Daily (eds). Encyclopedia of Library and Information Science. Marcel Dekker. 1977. vol 21. pp [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA131#v=onepage&q&f=false 131] to 176. Bibliography *Jozef Rogala. A Collector's Guide to Books on Japan in English: An Annotated List of Over 2500 Titles with Subject Index. 2001. [https://books.google.co.uk/books?id=7KI9ao-w2FEC&pg=PP1#v=onepage&q&f=false] *Ria Koopmans-de Bruijn. Area Bibliography of Japan. (Scarecrow Area Bibliographies). Scarecrow Press. 1998. [https://books.google.co.uk/books?id=Hlx2OMjgUi0C&pg=PR1#v=onepage&q&f=false] *Frank Joseph Shulman. Japan. (World Bibliographical Series, vol 103). Clio Press. 1989. [https://books.google.co.uk/books?id=LsoUAQAAIAAJ] *Eibun Nihon Kankei Tosho Mokuroku, 1945-1981. (Japanese: 英文日本関係図書目録, 1945-1981). (English: Catalogue of Books in English on Japan, 1945-1981). Japan Foundation. Tokyo. 1986. *Japan: analytical bibliography: with supplementary research aids: and selected data on Okinawa . . . Department of the Army. Washington. 1972. [https://books.google.co.uk/books?id=h4d4nYxrxtMC&pg=PP7#v=onepage&q&f=false] *Books on Japan in Western Languages. The International Christian University Library. 1971. [https://books.google.co.uk/books?id=F2bQAAAAMAAJ] *Books on Japan: A List of Acquisitions, 1955-1970. International House of Japan Library. 1971. [https://books.google.co.uk/books?id=F8sWAQAAIAAJ] *Fukuda. Union Catalog of Books on Japan in Western Languages. 1968. [https://books.google.co.uk/books?id=HKYyAQAAIAAJ] *A Classified List of Books in Western Languages Relating to Japan. University of Tokyo Press. 1965. [https://books.google.co.uk/books?id=U8MUAQAAIAAJ] *Katsuji Yabuki (ed). Japan Bibliographic Annual. Published by the Hokuseido Press for the Japan Writers Society. 1956 and 1957. **Japan Bibliographic Annual 1956. [https://books.google.co.uk/books?id=9XLQAAAAMAAJ] **Japan Bibliographic Annual 1957. [https://books.google.co.uk/books?id=vesSAAAAIAAJ]. Reviews: (1957) 13 Monumenta Nipponica 166 (April-July) [https://books.google.co.uk/books?id=8S1yb-iwrOwC] (1957) 25 The Oriental Economist 212 (April) [https://books.google.co.uk/books?id=QELoAAAAMAAJ] *Haring. Books on Japan: A Reference List. 1955. [https://books.google.co.uk/books?id=RbDoAAAAMAAJ] *Borton. A Selected List of Books and Articles on Japan in English, French, and German. 1940: [https://books.google.co.uk/books?id=YYIsAAAAYAAJ]. Revised and enlarged. Harvard University Press. 1954: [https://books.google.co.uk/books?id=F8O2VwJUPUkC]. **A Selected List of Books on Japan in Western Languages (1945-1960). (Studies on Asia Abroad, vol 1). The Information Centre of Asian Studies, The Toyo Bunko. 1964. [https://books.google.co.uk/books?id=i1_QAAAAMAAJ] *Oskar Nachod. Bibliography of the Japanese Empire 1906-1926. 1928. [https://archive.org/details/bibliographyofja0001oska/page/n8/mode/1up vol 1]. [https://archive.org/details/bibliographyofja0002oska/page/n6/mode/1up vol 2]. *Fr. von Wenckstern. A Bibliography of the Japanese Empire: being a Classified List of All Books, Essays and Maps in European Languages relating to Dai Nihon (Great Japan) published in Europe, America and in the East from 1859-93 . . . 1895. vol 1. [https://books.google.co.uk/books?id=dcVAAAAAYAAJ&pg=PR1#v=onepage&q&f=false] [https://books.google.co.uk/books?id=v7lO4ddqDywC&pg=PR3#v=onepage&q&f=false] **Volume 2, from 1894 to the middle of 1906. 1907. [https://archive.org/details/bibliographyofja0002frvo/page/n6/mode/1up] *Hyman Kublin. What Shall I Read on Japan? An Introductory Guide. Japan Society, New York. 1971. [https://books.google.co.uk/books?id=yRRUAAAAYAAJ] *Henri Cordier. Bibliotheca Japonica: Dictionnaire Bibliographique des Ouvrages Relatifs a L'Empire Japonais. 1912. [https://archive.org/details/bibliothecajapon0008henr/page/n8/mode/1up] Japanese studies *An Introductory Bibliography for Japanese Studies. The Japan Foundation. [https://books.google.co.uk/books?id=53O6AAAAIAAJ] *Richard Perren. Japanese Studies from Pre-History to 1990: A Bibliographical Guide. 1992. [https://books.google.co.uk/books?id=CN9RAQAAIAAJ&pg=PP1#v=onepage&q&f=false]. "Bibliographies" at pp 1 to 3. *K.B.S. Bibliography of Standard Reference Books for Japanese Studies, with Descriptive Notes. University of Tokyo Press. [https://books.google.co.uk/books?id=95wbAAAAMAAJ] *[[w:en:Monumenta Nipponica|Monumenta Nipponica]] *[[w:en:Japan Forum|Japan Forum]]. British Association for Japanese Studies. [https://www.tandfonline.com/journals/rjfo20] *Japanese Studies. Japanese Studies Association of Australia. ISSN 1037-1397. [https://www.tandfonline.com/journals/cjst20] *[[w:en:The Journal of Japanese Studies|The Journal of Japanese Studies]]. University of California Press. *Nichibunken Newsletter. [[w:en:International Research Center for Japanese Studies|International Research Center for Japanese Studies]]. [https://books.google.co.uk/books?id=5TnjAAAAMAAJ] [https://www.nichibun.ac.jp/en/publications/data/news/] [https://newsletter.nichibun.ac.jp/en/] History and culture *John W Dower. Japanese History & Culture from Ancient to Modern Times: Seven Basic Bibliographies. 1986. [https://books.google.co.uk/books?id=NX67AAAAIAAJ&pg=PP1#v=onepage&q&f=false]. "Bibliographies & Research Guides" at chapter 6. Research guides *Mindy L Kotler. Information Gathering on Japan: A Primer. Search Associates. 1988. ISBN 9780962546006. Catalogue: [https://search.worldcat.org/zh-cn/title/Information-gathering-on-Japan-Joho-:-a-primer/oclc/20530148]. Review: (1989) [https://books.google.co.uk/books?id=NZLiAAAAMAAJ 27] Choice 82 Encyclopedias See also [[w:ja:Japanese encyclopedias]] *Louis Frédéric. [[w:Japan Encyclopedia|Japan Encyclopedia]]. Translated by Käthe Roth. 2002. [https://books.google.co.uk/books?id=p2QnPijAEmEC&pg=PP1#v=onepage&q&f=false] **Louis Frédéric. Le Japon: Dictionnaire et Civilisation. Robert Lafont. Paris. 1996. ISBN 2-221-06764-9. *Japan: An Illustrated Encyclopedia. Kodansha. 1993. **Japan: Profile of a Nation. Kodansha. 1995. Revised Edition. 1999. *[[w:Kodansha Encyclopedia of Japan|Kodansha Encyclopedia of Japan]]. 1983. Supplement. 1986. [https://books.google.co.uk/books?id=WvApAQAAMAAJ] *Dorothy Perkins. Encyclopedia of Japan: Japanese History and Culture, from Abacus to Zori. Facts on File. A Roundtable Press Book. 1991. [https://books.google.co.uk/books?id=JLKGAAAAIAAJ] *Pictorial Encyclopedia of Modern Japan. Gakken. 1986. [https://books.google.co.uk/books?id=0FgKAQAAIAAJ] *Boye Layfayette De Mente. Japan Encyclopedia. 1995. [https://books.google.co.uk/books?id=f9c7AAAAMAAJ] **Boye De Mente. Everything Japanese. [The Authoritave Reference on Japan Today]. 1989. [https://books.google.co.uk/books?id=Duku89bARgoC] Biographical dictionaries *Wispelway. Japanese Biographical Index [https://books.google.co.uk/books?id=4UkhAAAAQBAJ&pg=PR3#v=onepage&q&f=false] *Seiichi Iwao. Biographical Dictionary of Japanese History. Kodansha International. 1978.[https://books.google.co.uk/books?id=TkQOAQAAMAAJ] *Senʼichi Hisamatsu. Biographical Dictionary of Japanese Literature. Kodansha International. 1976. [https://books.google.com/books?id=X3lkAAAAMAAJ] *Yutaka Tazawa (ed). Biographical Dictionary of Japanese Art. Kodansha International. 1981. [https://books.google.com/books?id=7ozrAAAAMAAJ] *Japan Biographical Encyclopedia & Who's Who. 1958. Review: [https://books.google.co.uk/books?id=lV_VAAAAMAAJ 25] Contemporary Japan 280 **Japan Biographical Encyclopedia & Who's Who (2nd Edition) 1961. The Japan Biographical Research Department, The Rengo Press Ltd. Preface dated October 1960. Commentary: [https://books.google.co.uk/books?id=-SZSAAAAMAAJ] ***1961 Supplement. December 1961. *Shunjiro Kurita. [[w:ja:Who's Who in Japan|Who's Who in Japan]]. [https://archive.org/details/WhosWhoInJapan1913/page/n24/mode/1up 2nd Ed]. Catalogue: [https://cir.nii.ac.jp/crid/1971712334741056302]. **[[w:ja:石川安次郎|Yasujiro Ishikawa]] (ed). Fifth Annual Edition. The Who's Who in Japan Publishing Department: The Keiseisha. No 15, 2-chome, Owari-cho, Ginza, Kyobashi-ku, Tokyo. Preface dated May 1916. [https://books.google.co.uk/books?id=joBJAAAAYAAJ]. Yasujiro Ishikawa's biography "Ishikawa Yasujiro" is on p 213. *Who's Who in Japan 1984/85. International Culture Institute. Hong Kong. [https://books.google.co.uk/books?id=5a0MAQAAMAAJ]. Reviews: [https://books.google.co.uk/books?id=_xVnAAAAMAAJ 16(2)] World Affairs Report col 349; The Journal of the American Chamber of Commerce in Japan, [https://books.google.co.uk/books?id=Aa62AAAAIAAJ November 1984], p 71. *Who's Who in Japanese Government. Review: [https://books.google.co.uk/books?id=91I3AAAAIAAJ 29] RQ 304 (Winter 1989). Reference books *Nihon No Sanko Tosho. Volume 1: 1965. Volume 2: 1972. **Guide to Japanese Reference Books. American Library Association. Chicago. 1966: [https://books.google.co.uk/books?id=0rflAAAAMAAJ]. Supplement. 1979: [https://books.google.co.uk/books?id=j05_F9OHzkQC]. Commentary: Encyclopedia of Library and Information Science, vol 21, [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA149#v=onepage&q&f=false p 149]. Media *[https://www.bbc.com/news/world-asia-pacific-15217593 Japan media guide]. News. BBC. 20 March 2023. *Masaaki Kasagi. Mass Media in Japan. (Orientation seminars on Japan, number 14). 1983. [https://books.google.co.uk/books?id=odkgAAAAIAAJ] *Routledge Handbook of Japanese Media [https://books.google.co.uk/books?id=zilKDwAAQBAJ&pg=PA1#v=onepage&q&f=false] Publishers *[https://www.publishersweekly.com/pw/by-topic/international/international-book-news/article/99729-get-to-know-these-japanese-publishing-companies.html Get to Know These Japanese Publishing Companies]. Publishers Weekly. 20 February 2026. Press and journalism *[https://reutersinstitute.politics.ox.ac.uk/digital-news-report/2025/japan Japan]. Reuters Institute for the Study of Journalism. 17 June 2025. *Marjane Aalam and Philippe Régnier. The Japanese Press and Information System. The Graduate Institute of International Studies. Geneva. [https://books.google.co.uk/books?id=RTcbAQAAIAAJ] *The Japanese Press: Past and Present. Japan Newspaper Publishers' and Editors' Association. [https://books.google.co.uk/books?id=5tcQAAAAIAAJ 1949]. *Anthony Rausch. Japanese Journalism and the Japanese Newspaper: A Supplemental Reader. [https://books.google.co.uk/books?id=mZrToQEACAAJ] *Frank L Martin. The Journalism of Japan. 1918. [https://books.google.com/books?id=ruYzAQAAMAAJ] *William De Lange. A History of Japanese Journalism. Japan Library. 1998. [https://books.google.co.uk/books?id=Rd5tb0cuz8QC&pg=PP1#v=onepage&q&f=false] *Kanesada Hanazono. The Development of Japanese Journalism. Osaka. 1924. [https://books.google.co.uk/books?id=z99ZAAAAMAAJ] *Kanesada Hanazono. Journalism in Japan and Its Early Pioneers. 1926. [https://books.google.co.uk/books?id=IGTFfLc4bq0C] *César Castellvi. A Sociology of Journalism in Japan: The Last Empire of the Press. 2024. [https://books.google.co.uk/books?id=a2z8EAAAQBAJ&pg=PR4#v=onepage&q&f=false] *"Japan". Christopher H Sterling (ed). Encyclopedia of Journalism. A Sage Reference Publication. 2009. ISBN 9780761929574. vol 3. pp [https://books.google.co.uk/books?id=ZQhDq8fPj2IC&pg=PA809#v=onepage&q&f=false 809] to 815. Press annuals *The Japanese Press. (Nihon Shinbun Kyokai). [https://books.google.co.uk/books?id=AfvyAAAAMAAJ 1979] [https://books.google.co.uk/books?id=Au3yAAAAMAAJ 1998] Summaries of the press *Daily Summary of Japanese Press Foreign correspondents *Foreign Correspondents in Japan: Reporting a Half Century of Upheavals, from 1945 to the Present. Tuttle. 1998. [https://books.google.co.uk/books?id=YI3TAgAAQBAJ&pg=PP1#v=onepage&q&f=false] Periodicals *G Raymond Nunn (comp). Japanese Periodicals and Newspapers in Western Languages: An International Union List. Mansell. 1979. [https://books.google.co.uk/books?id=jEROAQAAIAAJ] *Japan Periodicals. Keizai Koho Center. 3rd Ed [https://books.google.co.uk/books?id=ATm0AAAAIAAJ]. Japan Periodicals, 1982. [https://books.google.co.uk/books?id=PkMyAAAAMAAJ] *Japanese Periodicals Index **Humanities and Social Sciences [https://books.google.co.uk/books?id=nXX_RpPGf3AC] **Natural Sciences [https://books.google.co.uk/books?id=FCJIAAAAYAAJ] *Current Japanese Periodicals [https://books.google.co.uk/books?id=FjO5AAAAIAAJ] *Check-list of Japanese Periodicals Held in British University and Research Libraries. [https://books.google.co.uk/books?id=VZgsAAAAYAAJ] *Union List of Current Japanese Periodicals in the East Asian Libraries of Columbia, Harvard, Princeton, and Yale Universities. [https://books.google.co.uk/books?id=yw7kAAAAMAAJ] *List of Japanese Periodicals in the Library of the School of Oriental & African Studies. [https://books.google.co.uk/books?id=RREjAQAAIAAJ] *Gianni Simone. [https://www.japantimes.co.jp/community/2011/04/26/issues/english-mags-approach-milestone-crossroads/ English mags approach milestone, crossroads]. The Japan Times. 26 April 2011. *Japan Report (1955 onwards) (Consulate General of Japan, Japan Information Center). Vol 39 published in 1993. [https://books.google.co.uk/books?id=MX4BN_frv4IC&pg=PP7#v=onepage&q&f=false] editions:jYuMSMIQC-AC **Japan Information *Japan Now [https://books.google.co.uk/books?id=Nul7DRQaexMC&pg=PP7#v=onepage&q&f=false] *Japan Quarterly. (Asahi Shimbun). 1954 to 2001. [https://books.google.co.uk/books?id=nZMMAQAAMAAJ] [https://books.google.co.uk/books?id=_RwVAAAAMAAJ] 189 issues. *Japan Illustrated: The Japan Times Quarterly [Pictorial] Magazine (October 1963 to Summer 1977) 15 vols [https://books.google.co.uk/books?id=D7UThOmE8T4C] *[[w:Japan Spotlight|Japan Spotlight]]. Economy, Culture & History: Japan Spotlight: Bimonthly. [https://books.google.co.uk/books?id=i7C0AAAAIAAJ] *Focus Japan. (Japan External Trade Organization, JETRO). [https://books.google.co.uk/books?id=2fG2hsEZpRkC] *The Japan Journal [https://books.google.co.uk/books?id=2V3hAAAAMAAJ] [https://books.google.co.uk/books?id=CJwoAQAAMAAJ] *Japan Magazine. Muromachi Publicity Corporation. (vols 1 to 5: 1957 to 1963). [https://books.google.co.uk/books?id=Swd18PnVeUgC] *The Japan Magazine: A Representative Monthly of Things Japanese [https://books.google.co.uk/books?id=ubGKo-p6O_0C] [https://archive.org/details/jm-1914-v4.9-5.2/mode/1up] *Transactions and Proceedings of the Japan Society, London [https://books.google.co.uk/books?id=B75nnph5qHgC&pg=PP5#v=onepage&q&f=false] **Bulletin. [Bulletin of the Japan Society, London.] [https://books.google.co.uk/books?id=Pd9KvyhnpjMC] **The Japan Society of London Bulletin [https://books.google.co.uk/books?id=XxlxAAAAMAAJ] *About Japan. Japan Society, New York. [https://books.google.co.uk/books?id=Nf5OAQAAIAAJ] **News Bulletin [https://archive.org/details/bub_gb_QcA3AQAAIAAJ/page/n2/mode/1up] *[[w:en:Metropolis (free magazine)|Metropolis]] (metropolisjapan.com) *[[w:en:Tokyo Weekender|Tokyo Weekender]] (トーキョー・ウィークエンダー) [https://www.tokyoweekender.com/japan-life/news-and-opinion/nhk-world-features-the-tokyo-weekender-magazine/] *The Japan Gazette [https://books.google.co.uk/books?id=WSopAAAAYAAJ&pg=PA1#v=onepage&q&f=false] *The Tokio Times [https://books.google.co.uk/books?id=UDfiFBu0vB4C&pg=PA1#v=onepage&q&f=false] *[[w:en:Look Japan|Look Japan]]. (Look Japan Ltd). [https://books.google.co.uk/books?id=QnO6AAAAIAAJ]. Commentary: Gale Directory of Publications and Broadcast Media [https://books.google.co.uk/books?id=ve4dAQAAMAAJ] *[[w:en:Japan Echo|Japan Echo]]. 1974 to 2010. [https://books.google.co.uk/books?id=Cmq6AAAAIAAJ] [https://books.google.co.uk/books?id=fpmEPpl-85UC] *PHP Intersect. (Where Japan Meets Asia and the World). PHP Institute. [https://books.google.co.uk/books?id=i74TAQAAMAAJ] **Intersect Japan [https://books.google.co.uk/books?id=sL8TAQAAMAAJ] *Japan Digest [https://books.google.co.uk/books?id=8AcOAQAAMAAJ] *Speaking of Japan [https://books.google.co.uk/books?id=U7S0AAAAIAAJ]. [Speeches.] *The Hansei Zasshi: A Monthly Magazine [https://books.google.co.uk/books?id=6qBhfHZo7Q0C&pg=PP5#v=onepage&q&f=false][https://books.google.co.uk/books?id=dyIsvnYjpwEC&pg=PP6#v=onepage&q&f=false] **The Orient. 1899 onwards [https://books.google.co.uk/books?id=nS1omYYnnd4C&pg=PP5#v=onepage&q&f=false] *Today's Japan. Orient/West Incorporated. [https://books.google.co.uk/books?id=g2ASAAAAMAAJ] *Japan Review: Bulletin of the International Research Center for Japanese Studies. [https://books.google.co.uk/books?id=GggOAQAAMAAJ] *[https://www.bloomberg.com/account/newsletters/next-japan Next Japan]. Bloomberg. *Niponica. [https://books.google.co.uk/books?id=X2scKgfQS5oC] Newspapers See also [[w:List of newspapers in Japan]] *Haruhara Akihiko, "English-language newspapers in Japan" (1994) 41 Japan Quarterly [https://www.proquest.com/openview/8e2b760f2a2fa37ba164ea675c095353/1 474] (Issue 4: October 1994) *James Charles Tanner. English Language Newspapers in Bakumatsu Japan. 1977. [https://books.google.co.uk/books?id=Bn2zgzZy_3oC] *[https://www.japantimes.co.jp/news/2009/03/03/reference/newspapers-here-soldiering-on/ Newspapers here soldiering on]. The Japan Times. 3 March 2009. *[[w:The Japan Times|The Japan Times]] **The Japan Times: Weekly Edition [https://books.google.co.uk/books?id=KoQ-AQAAMAAJ] [https://books.google.co.uk/books?id=yYQ-AQAAMAAJ&pg=PA1#v=onepage&q&f=false] *Japan Daily Mail *Japan Weekly Mail *The Japan Chronicle **Weekly Edition [https://books.google.co.uk/books?id=vXdRAQAAIAAJ&pg=PA1#v=onepage&q&f=false] *The Japan News. (The Japan News by The Yomiuri Shimbun) **Yomiuri Japan News (from 1955) **The Yomiuri (from 1958) **The Daily Yomiuri (from 1970) *The Asahi Shimbun: Asia & Japan Watch. [https://www.asahi.com/sp/ajw/] **Asahi Evening News (from 1954) ***Tokyo Evening News (1952 to 1954) [https://ndlsearch.ndl.go.jp/books/R100000002-I000000145073] *The Mainichi. [https://mainichi.jp/english/] **Mainichi Daily News (1922 to 2001) [https://www.nytimes.com/2001/02/27/business/worldbusiness/IHT-tech-briefstop-the-presses.html] [https://ndlsearch.ndl.go.jp/books/R100000002-I000000144910] Sports newspapers; sports dailies *Louise do Rosario, "News-stand stars" in "Japan" (1992) [https://books.google.co.uk/books?id=T_GzAAAAIAAJ 155] [[w:en:Far Eastern Economic Review|Far Eastern Economic Review]], 24 to 31 December 1992, p 21 *[[w:ja:岡崎満義|Mitsuyoshi Okazaki]], "Unsportsmanlike Journalism: Japan's sports dailies may be popular, but are they sporting?" in "Sport", [[w:en:Look Japan|Look Japan]], [https://books.google.co.uk/books?id=lD3tAAAAMAAJ January 1995], p 39 News *[[w:en:Japan Today|Japan Today]] (ジャパントゥデイ). GPlusMedia. Gakken Holdings. Annuals and year books *This is Japan. Asahi Shimbun. 1954 to 1971. [https://books.google.co.uk/books?id=2X9DAQAAIAAJ]. Commentary: A Victorian Sailor's Grave in the Seto Inland Sea, p 244 [https://books.google.co.uk/books?id=OegkAgAAQBAJ&pg=PA244#v=onepage&q&f=false] *The Japan Year Book. The Japan Year Book Office. 1905 onwards. [https://archive.org/details/bub_gb_arFPAAAAMAAJ/page/n10/mode/1up 1906]. [https://archive.org/details/in.ernet.dli.2015.553496/page/n27/mode/1up 1915]. *The "Japan Gazette" Japan Year Book. The Japan Gazette. [https://archive.org/details/japan-year-book-1913-1914/page/n15/mode/1up 1913-14] *The Japan Times Year Book *New Japan. Mainichi Newspapers. [https://books.google.co.uk/books?id=gRFCAQAAIAAJ] Almanacs *Asahi Shimbun Japan Almanac. [https://books.google.co.uk/books?id=SEEEAQAAIAAJ 1995]. *Japan Almanac. (The Mainichi Newspapers). [https://books.google.co.uk/books?id=ufAIAQAAIAAJ 1972]. [https://books.google.co.uk/books?id=X4eXWRkbtFsC 1973]. [https://books.google.co.uk/books?id=7rMrAAAAIAAJ] [https://books.google.co.uk/books?id=krMrAAAAIAAJ] *[[w:Boyé Lafayette De Mente|Boye De Mente]]. Passport's Japan Almanac. [https://books.google.co.uk/books?id=741wAAAAMAAJ] General *Japan: A Country Study. (Area Handbook series). 4th Ed: 1983: [https://books.google.co.uk/books?id=HkM5N3JNc5IC]. 5th Ed: 1992: [https://books.google.co.uk/books?id=ze-wupXxpvEC] *Area Handbook for Japan. 2nd Ed: 1964: [https://books.google.co.uk/books?id=WucdAAAAMAAJ&pg=PR1#v=onepage&q&f=false]. 3rd Ed: 1974: [https://books.google.co.uk/books?id=LG2aoq1U_eoC&pg=PR1#v=onepage&q&f=false] (DA Pam 550-30). *Colin Simpson. Picture of Japan. **Japan: An Intimate View. A S Barnes. [https://books.google.co.uk/books?id=3hkeAAAAMAAJ] **This is Japan. Angus & Robertson. [https://books.google.co.uk/books?id=HJEJAQAAIAAJ] *Japan. (The World and Its Peoples). Greystone Press, New York. 1964. Volume 1: [https://books.google.co.uk/books?id=yysUAQAAMAAJ]. Volume 2 "Japan Korea", including Korea: [https://books.google.co.uk/books?id=uQAUAQAAMAAJ]. See pp 1 to 375 for Japan, and pp 376 to 379 for Ryukyu and Bonin Islands. *Japan. (World and its Peoples: Eastern and Southern Asia, volume 8). Marshall Cavendish. 2008. ISBN 9780761476412. *Edward Seidensticker. This Country, Japan. Kodansha International. 1979. ISBN 9780870112294. [https://books.google.co.uk/books?id=88wwAQAAIAAJ] *Hall and Beardsley. Twelve Doors to Japan. McGraw-Hill. New York. 1965. [https://books.google.co.uk/books?id=0KpxAAAAMAAJ] *"Japan". Louis Barron (ed). "Asia & Australasia". Moshe Y Sachs (ed and pub). Worldmark Encyclopedia of the Nations. Worldmark Press, Inc. Harper & Row New York. 1963. pp 145 to 160. [https://books.google.co.uk/books?id=I0oYAQAAMAAJ] **"Japan". Asia & Oceania. 7th Ed: 1988. ISBN 0-471 62406-3. vol 4. pp 153 to 168. **"Japan". Asia & Oceania. 8th Ed: 1995. Gale Research Inc. ISBN 0-8103-9882-6. vol 4. pp 203 to 220. *James E Hoare. "Japan". East and Southeast Asia. The World Today Series 2023–2024. pp [https://books.google.co.uk/books?id=3GfQEAAAQBAJ&pg=PA107#v=onepage&q&f=false 107] to 133. *Japan. (Library of Nations). Time Life Books. 1985. ISBN 0809453347. ISBN 0705408485. [https://books.google.co.uk/books?id=P1NJwcWAnboC] [https://books.google.co.uk/books?id=Ui2CvuyM4JkC] Handbooks *Patrick Heenan (ed). The Japan Handbook. (Regional Handbooks of Economic Development). 1998. [https://books.google.co.uk/books?id=IMG2AgAAQBAJ&pg=PP1#v=onepage&q&f=false] Introduction *Introducing Japan Through Books: A Selected Bibliography. Public Information Bureau, Ministry of Foreign Affairs, Japan. 1968. [https://books.google.co.uk/books?id=FvsyAQAAIAAJ]. 2nd Ed: 1973: [https://books.google.co.uk/books?id=Vj0XAQAAMAAJ]. *Donald Ritchie. Introducing Japan. 1st Ed: 1978. Revised Ed: 1986. 6th printing: 1989: [https://books.google.co.uk/books?id=FE-nxxoKayQC]. 2nd Revised Ed: 1990. 2nd printing: 1991: [https://books.google.co.uk/books?id=hz4UAQAAIAAJ]. 1994: [https://books.google.co.uk/books?id=FMvT6m4SgIQC&pg=PP1#v=onepage&q&f=false]. *Herschel Webb. An Introduction to Japan. Columbia University Press. 2nd Ed: 1957: [https://books.google.co.uk/books?id=YQ8MAQAAIAAJ]. *Introducing Modern Japan. A publication of the Japan Information and Culture Center, Embassy of Japan. Today and yesterday *Ray Downs. Japan Yesterday and Today. Praeger Publishers. 1970. [https://books.google.co.uk/books?id=PwKxAAAAIAAJ] Today *Roger Buckley. Japan Today. Cambridge University Press. 3rd Ed [https://books.google.co.uk/books?id=thyqBtJp2DcC&pg=PP1#v=onepage&q&f=false] Contemporary *Routledge Handbook of Contemporary Japan. 2021. [https://books.google.co.uk/books?id=yfH3DwAAQBAJ&pg=PA2011#v=onepage&q&f=false] *Duncan McCargo. Contemporary Japan. 3rd Ed: 2012. [https://books.google.co.uk/books?id=8I5KEAAAQBAJ&pg=PP1#v=onepage&q&f=false] *Jeff Kingston. Contemporary Japan: History, Politics, and Social Change since the 1980s. 2011. [https://books.google.co.uk/books?id=enJQZA3R4FMC&pg=PP1#v=onepage&q&f=false] [Series] *Routledge Contemporary Japan Series Modern *Hugh Cortazzi. Modern Japan: A Concise Survey. Palgrave Macmillan. 1993. [https://books.google.co.uk/books?id=Cf--DAAAQBAJ&pg=PP1#v=onepage&q&f=false] The Japanese *Peter Tasker. The Japanese: Portrait of a Nation. 1989 [https://books.google.com/books?id=Q1N8ld78wwQC] **The Japanese: A Major Exploration of Modern Japan. [https://books.google.co.uk/books?id=CW-6AAAAIAAJ] **Inside Japan: Wealth, Work and Power in the New Japanese Empire. 1987. [https://books.google.co.uk/books?id=2OJuAAAAMAAJ] *Edwin O Reischauer. The Japanese. The Belknap Press of Harvard University Press. [https://books.google.co.uk/books?id=zrEqAAAAYAAJ] *Edwin O Reischauer and Marius B Jansen. The Japanese Today: Change and Continuity. 1995. [https://books.google.co.uk/books?id=BTPNlLIy2soC&pg=PP1#v=onepage&q&f=false] Japaneseness *Ray T. Donahue (ed). Exploring Japaneseness: On Japanese Enactments of Culture and Consciousness. Ablex Publishing. 2002. [https://books.google.co.uk/books?id=V_NwAAAAMAAJ] *Yoji Yamakuse. Japaneseness: A Guide to Values and Virtues. 2016. [https://books.google.co.uk/books?id=tB0iDAAAQBAJ&pg=PP1#v=onepage&q&f=false] Travel books *DK Eyewitness Travel: Japan. Reprinted with revisions. 2015: [https://books.google.co.uk/books?id=g2NaBgAAQBAJ&pg=PP1#v=onepage&q&f=false]. 2017: [https://books.google.co.uk/books?id=vg15DQAAQBAJ&pg=PP1#v=onepage&q&f=false]. *Dodd and Richmond. The Rough Guide to Japan. 2nd Ed: 2001: [https://books.google.co.uk/books?id=pRGq95ytWZoC&pg=PP1#v=onepage&q&f=false]. *Frommer's Japan. 5th Ed: 2000: [https://books.google.co.uk/books?id=-QC8mVyvPa8C]. *Fodor's Japan YYYY. 1984. [https://books.google.co.uk/books?id=aH2Ow27HUQ0C 1986]. [https://books.google.co.uk/books?id=3gTTf6nbv20C 1987]. 1988. **Fodor's YY Japan. [https://books.google.co.uk/books?id=9QMHllzldlYC 91]. 92. 93. **Fodor's Japan. 13th Ed: 1996: [https://books.google.co.uk/books?id=cZxZAAAAYAAJ] *The New Official Guide: Japan. Japan Travel Bureau. 1966. [https://books.google.co.uk/books?id=HoxxAAAAMAAJ] *Here is Japan. Asahi Broadcasting Corporation. [https://books.google.co.uk/books?id=8QXRCTMNG7MC] *Japan. (Nagel Travel Guide Series, vol 32). 1964. [https://books.google.co.uk/books?id=QsbXAAAAMAAJ] *Clark. All the Best in Japan: with Manila, Hong Kong, and Macao. ("All the Best" series). 1959. Reprinted 1964. [https://books.google.co.uk/books?id=yUq4YaaryrwC]. Reviews: [https://archive.dartmouthalumnimagazine.com/article/1958/6/1/all-the-best-in-japan] (1958) 110 Travel 51 [https://books.google.co.uk/books?id=UVwXAQAAMAAJ] 3 Bulletin of the Japan Society, London, No 11: June 1960, p 25 [https://books.google.co.uk/books?id=2oy74hRRXk4C] **All the Best in Japan and the Orient. 1967. Night *[[w:ja:Taizo Fujimoto|Taizo Fujimoto]]. The Nightside of Japan. T Werner Laurie. Essex Street, Strand, London. 1914. [https://archive.org/details/nightsideofjapan00fujirich/page/n6/mode/1up] Exhibitions *Patricia Morison. "Fun and games with Japanese angst". The Financial Times. Weekend 21/22 September 1991. No 31562. Section II: "Weekend FT". Weekend 21/22 September 1991. Page xx. ["Visions of Japan" exhibition, Victoria and Albert Musuem, ending 5 January 1992.] Languages See [[Universal Bibliography/Languages/Japanese|Japanese]] Literature See [[Universal Bibliography/Literature#Japanese|Japanese literature]] Music See [[Universal Bibliography/Music#Japanese and Japan|Music of Japan]] Cinema See [[Universal Bibliography/Cinema#Japanese|Cinema of Japan]] Television See [[Universal Bibliography/Television#Japanese|Japanese television]] Architecture See [[Universal Bibliography/Architecture|Japanese architecture]] Culture See [[Universal Bibliography/Culture#Japanese|Culture of Japan]] Economy *MERI's Monthly Circular: Survey of Economic Conditions in Japan (1923 to 2025) Mitsubishi Economic Research Institute [https://books.google.co.uk/books?id=4QDtAAAAMAAJ] [https://www.meri.or.jp/en/mc.html] Tokyo *J S Eades. Tokyo. (World Bibliographical Series, vol 214). CLIO Press. 1999. ISBN 1-85109-292-7. [https://books.google.co.uk/books?id=TrkUAQAAIAAJ] ==Korea== *Korea Journal [https://books.google.co.uk/books?id=O6XfBexsp6gC] Bibliography and literature *Thomas H Kang. "Korean Literature and Bibliography". Kent, Lancour and Daily (eds). Encyclopedia of Library and Information Science. Marcel Dekker. 1977. vol 21. pp [https://books.google.co.uk/books?id=H1pNvzr_n98C&pg=PA176#v=onepage&q&f=false 176] to 240. [[Category:Countries]] h440nlkzfom6obw8deoh6fa3d3i1cic 2 274794 2844945 2764603 2026-11-09T07:07:01Z RCraig09 353272 fixing mentions of x- and y-axes . . . . Also removed perplexing statement re axis labels not being present 2844945 wikitext text/x-wiki {{DISPLAYTITLE:<span style="font-size:0">{{NAMESPACE}}:{{BASEPAGENAME}}/</span>{{SUBPAGENAME}}}} {{Robelbox|theme=9|title=Page 9|width=100%}} <div style="{{Robelbox/pad}}"> <blockquote> [[File:20201112 Tidal flooding graph - Annapolis, Maryland.svg|frameless|center]] </blockquote> {{center|<big>This is a '''histogram''', a graph that displays data in a bar. This specific histogram displays the number of days of tidal floodings [y-variable] vs. years [x-variable] in Annapolis, Maryland.</big>}} <small>'''Source: [https://commons.wikimedia.org/wiki/File:20201112_Tidal_flooding_graph_-_Annapolis,_Maryland.svg Commons Wikimedia, Img]'''</small> </div> {{Robelbox/close}} {{center|'''''[[User:Atcovi/StatsProject/Correlation|Page 10]]''''' »»»}} [[Category:Atcovi's Statistics Project 20/21]] dw4lu6zg7wylvka9u0g0ojy4r3tdy7v 2 289273 2844882 2844858 2026-11-08T17:06:33Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844882 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. The proton has the symmetry of the 4-simplex polytope. The neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope. Its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate inertial (non-rotating) reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integral number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. The 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. Both the 120-point 600-cell and the 600-point 120-cell are divisible into an integral number of non-disjoint 4-orthoplexes which share axes. The 600-point 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames. Two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. Thus for example any configuration of the element Helium with 2 protons occupies at least 10 distinct vertices of the 600. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} lr6ykauy0z22cmjizu5ai2wm3kpio0p 2844899 2844882 2026-11-08T22:09:01Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844899 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. The proton has the symmetry of the 4-simplex polytope. The neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into an integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 600-point 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames. Two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. Thus for example any configuration of the element Helium with 2 protons occupies at least 10 distinct vertices of the 600. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} tizd54zi8gcjz2ahfskp1cc9mi03ur5 2844900 2844899 2026-11-08T22:11:52Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844900 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. The proton has the symmetry of the 4-simplex polytope. The neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 600-point 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames. Two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. Thus for example any configuration of the element Helium with 2 protons occupies at least 10 distinct vertices of the 600. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} ee1wyf33hnazsz459ox0lwlyy98yq1q 2844902 2844900 2026-11-08T22:41:24Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844902 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. The proton has the symmetry of the 4-simplex polytope. The neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} h163l3x8yizgy4qm4yz6sircgw7yji0 2844903 2844902 2026-11-08T22:43:03Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844903 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. The proton has the symmetry of the 4-simplex polytope. The neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} n9gfq0gcvg4vux44e9msqkb7agh08ok 2844907 2844903 2026-11-08T23:11:27Z Dc.samizdat 2856930 /* Summary */ 2844907 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 2w1k4c8yc36ippafsb2pavn3hla5h6z 2844909 2844907 2026-11-08T23:14:52Z Dc.samizdat 2856930 /* Summary */ 2844909 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 8fz4pohl6vy39r6cx470zdulwzlzjma 2844910 2844909 2026-11-08T23:23:43Z Dc.samizdat 2856930 /* Summary */ 2844910 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a <math>4</math>-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 7impd6jkuepc4fxqknydca21cjv2v82 2844911 2844910 2026-11-08T23:27:02Z Dc.samizdat 2856930 /* Summary */ 2844911 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 70rafwqkh18g96x9fy6175bt9ke6i2e 2844912 2844911 2026-11-08T23:28:13Z Dc.samizdat 2856930 /* Summary */ 2844912 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, in a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 45xld3lwf0iavcd44z67oiierbudyv1 2844913 2844912 2026-11-08T23:31:30Z Dc.samizdat 2856930 /* Summary */ 2844913 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A typical galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 70rafwqkh18g96x9fy6175bt9ke6i2e 2844914 2844913 2026-11-08T23:52:23Z Dc.samizdat 2856930 /* A theory of the Euclidean cosmos */ 2844914 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker at center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} c7cukoi9lod8vgqf6sqrrh95e7ndb4q 2844917 2844914 2026-11-09T00:08:37Z Dc.samizdat 2856930 /* A theory of the Euclidean cosmos */ 2844917 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space. That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} joyff0plxehg5514ymoa7kqjcosk16d 2844930 2844917 2026-11-09T04:21:42Z Dc.samizdat 2856930 /* General relativity is the geometry of gravity in Euclidean 4-space */ 2844930 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. For example, atoms exhibit <math>SO(4)</math> symmetries of the discrete isoclinic (equi-angled) double rotations (<math>\mathrm{Q^2}</math>) of a set of regular 4-polytopes that is characteristic of their [[w:Atomic_number|atomic number]]. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 2hlfpje2l1a7091p8a26r1weqar07vk 2844936 2844930 2026-11-09T06:23:59Z Dc.samizdat 2856930 /* Symmetries */ 2844936 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the perceived rates at which clocks run in distinct moving gravitational fields, just as special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} asz6v1es3z12b3xn38ucskaccxro6rn 2844938 2844936 2026-11-09T06:37:45Z Dc.samizdat 2856930 /* Special relativity is Galilean relativity in Euclidean 4-space */ 2844938 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>''Time ticks at the same rate everywhere in space.''</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} a2548uy6kzklu8y3sbdts0x2a0yuycf 2844939 2844938 2026-11-09T06:38:28Z Dc.samizdat 2856930 /* Special relativity is Galilean relativity in Euclidean 4-space */ 2844939 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each element is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atom of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations are potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An element of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraints mentioned. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that the more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} jnbrh6xjoa94nl09q76u9j0sivlmf7w 2844942 2844939 2026-11-09T07:03:29Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844942 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each atomic nucleus is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atomic nucleus of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An atomic nucleus of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraint above. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} t4jak35zd48sg5jrvfl1e6it7gw8gbz 2844943 2844942 2026-11-09T07:04:00Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844943 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each atomic nucleus is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atomic nucleus of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell. Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An atomic nucleus of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraint above. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} 42cuiufnfcx0f7nioi74zex1zg5todn 2844944 2844943 2026-11-09T07:06:57Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844944 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each atomic nucleus is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atomic nucleus of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell.{{Sfn|Waegell & Aravind|2014}} Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An atomic nucleus of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> not necessarily disjoint 4-orthoplexes. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the geometric constraint above. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} e1te0pwvzoc7sj5lc209zwokfy8xt85 2844948 2844944 2026-11-09T07:10:32Z Dc.samizdat 2856930 /* Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space */ 2844948 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each atomic nucleus is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atomic nucleus of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell.{{Sfn|Waegell & Aravind|2014}} Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An atomic nucleus of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> distinct 4-orthoplexes, not necessarily disjoint. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the constraints above. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} e55bw5ck5hm7ta2vtdbhn5o9l4t8qgt 2844962 2844948 2026-11-09T11:04:01Z Dc.samizdat 2856930 /* Special relativity is Galilean relativity in Euclidean 4-space */ 2844962 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space, at any time. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each atomic nucleus is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atomic nucleus of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell.{{Sfn|Waegell & Aravind|2014}} Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An atomic nucleus of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> distinct 4-orthoplexes, not necessarily disjoint. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the constraints above. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} mjaxj737hshx4b333xtae8r7kivm3eu 2844963 2844962 2026-11-09T11:05:45Z Dc.samizdat 2856930 /* Special relativity is Galilean relativity in Euclidean 4-space */ 2844963 wikitext text/x-wiki {{align|center|David Brooks Christie}} {{align|center|dc@samizdat.org}} {{align|center|Draft in progress}} {{align|center|June 2023 - October 2026}} <blockquote>'''Abstract:''' The physical universe is properly visualized as real Euclidean space <math>\mathbb{R}^4</math> of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are 4-polytopes, small round 4-dimensional objects, and stars are 4-balls of atomic plasma, large round 4-dimensional objects. We ourselves and the objects we observe near us are only 3-dimensional, but nonetheless we can see into four dimensions of space. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. Light from them reaches us directly, on straight lines through 4-space. This view of the observed universe is compatible with special and general relativity, and with quantum mechanics. It furnishes those theories with an explanatory geometric model.</blockquote> == Summary == We observe that: * Physical space is Euclidean with four perpendicular dimensions. * Atoms are [[W:4-polytope|4-polytopes]]. An atom's motion is the local product of its discrete self-reflections in Euclidean 4-space. * The sun is a [[W:4-ball|4-ball]] that is round in four dimensions. It occupies a hyperspherical region in Euclidean 4-space. * Everything of intermediate size between an atom and a star, including ourselves and our planet, lies in a 3-dimensional manifold of ordinary space, embedded in Euclidean 4-space. * Our entire 3-space manifold is moving at the speed of light <math>c</math> in Euclidean 4-space, a motion isomorphic to the passage of proper time. The gravitational coherence of galaxies is inertial coherence, a result of their linear motion at velocity <math>c</math> in Euclidean 4-space. * Special relativity describes the linear motion of objects and light signals in Euclidean 4-space. The propagation speed of light is <math>c\prime = 2c</math> measured on a straight line in Euclidean 4-space, notwithstanding the fact that it is <math>c</math> measured on a geodesic in our non-Euclidean 3-space. * General relativity describes the rotational motion of objects with mass in Euclidean 4-space. Time ticks at the same rate everywhere in Euclidean 4-space, notwithstanding the fact that its rate varies with the gravitational field. * Quantum mechanics describes the symmetry group actions of elementary geometric objects (4-polytopes) in Euclidean 4-space. We hypothesize that the proton has the symmetry of the 4-simplex polytope, and the neutron has the symmetry of the 4-orthoplex polytope. * The universe may properly be viewed as a 4-sphere centered wherever there is an observer. == A theory of the Euclidean cosmos == <blockquote>If we are to have any hope of understanding the universe, we must dare to imagine a world that is not bounded by our limited perspective.<ref>{{Cite book|first=Adam|last =Becker|year=2018|title=What Is Real? The Unfinished Quest for the Meaning of Quantum Physics}}</ref></blockquote> The physical universe is properly visualized as [[w:Four-dimensional_space|real Euclidean space <math>\mathbb{R}^4</math>]] of four orthogonal spatial dimensions. Space itself has a fourth perpendicular dimension, of which we are unaware in ordinary life. Atoms are [[w:4-polytope|4-polytopes]], small round 4-dimensional objects, and stars are [[W:4-ball|4-balls]] of atomic plasma, large round 4-dimensional objects. Objects intermediate in size between atoms and stars, including molecules, people, and planets (at their surfaces), are so flat as to be essentially 3-dimensional, having only the thickness of an atom in the orthogonal fourth dimension. All objects with mass move inertially through Euclidean 4-space at constant velocity <math>c</math> as long as they exist, and acceleration only varies their direction. Objects moving in the same direction are in the same inertial reference frame. Their direction of motion through 4-space at velocity <math>c</math> is their proper time dimension, simply because their direction and velocity of motion through time is the same as their direction and velocity of motion through space. A galaxy such as ours occupies a 4-ball of mostly empty space, with stars and other objects distributed non-uniformly within it. The galaxy's orbital center may be nothing: a smaller 4-ball of empty space they surround. The stars in our spiral galaxy appear from our accustomed point of view to occupy a disk-like region of 3-dimensional space, with a denser ball-like center, but they are not so confined: they are distributed within a region of 4-dimensional space. The disk and ball have thickness not only in the third dimension, but in the fourth spatial dimension as well. Light from stars and galaxies reaches us on straight lines through Euclidean 4-space, so from our viewpoint, in what we have always imagined to be a 3-space universe, we look into the surrounding 4-space. Although we are physically confined within a 3-dimensional hyperplane by the inertia of our motion through 4-space at constant velocity <math>c</math>, light signals are not so confined, so we observe all the cosmological objects surrounding us, both in and above or below our hyperplane, without perceiving their separation in our fourth orthogonal dimension, the direction of our motion. Several objects which appear to us to be located at almost the same point in our sky may actually lie in directions many degrees apart, since the entire hyperspherical sky is projected onto an ordinary sphere in our view of it. We may perceive a galaxy as elliptical when it is actually spherical, because that is how its image projects from its 4-ball shape into a 3-ball region in our hyperplane, where we detect it with our 3-dimensional bodies. More generally, orbits are circular in 4-space, but elliptical in the 3-space of their elliptic hyperplane. The galaxy as a whole, or more properly its orbital barycenter, is translating through 4-space at velocity <math>c</math>, in a distinct direction orthogonal to all three dimensions of our ordinary proper 3-space. Stars within the galaxy are translating with it at the same velocity <math>c</math> in the same direction, but on spiral trajectories as they pursue their various orbits within the galaxy. The galaxy as a whole occupies a 4-ball within its proper inertial reference frame (that is, in the moving frame of reference in which the galaxy considers itself to be a stationary rotating 4-ball). Over time, the galaxy 4-ball occupies a 4-dimensional cylinder and progresses along the cylinder's axis at velocity <math>c</math>. In this more universal inertial reference frame, the stars in the galaxy follow helical geodesic paths through the 4-cylinder; their trajectories are screw-translations through 4-space, the compound of a simple rotation and a completely orthogonal linear translation. The gravitational force and the inertial tendency to follow a geodesic are the same phenomenon, by the equivalence principle. That said, they can be distinguished, and the galaxy is held together primarily by gravity as inertia, not by gravity as attraction to a central mass toward which objects fall in orbit. There is not enough mass in the galaxy to hold it together by attraction, there is just enough to bend the stars' trajectories toward each other, in helical orbits around the galaxy's barycentric axis of motion. It is the tremendous inertial force of stars in translational motion at velocity <math>c</math> that holds the cylinder of motion together, not some invisible dark matter. The observed universe as a whole appears to be a [[W:3-sphere|3-sphere]] expanding radially from a central origin point at velocity <math>c</math>, the invariant velocity of mass-carrying objects through 4-space, also the propagation speed of light relative to any moving 3-space manifold, as measured by all observers. A 3-sphere is a hypersphere in Euclidean 4-space, but the bounding surface of a 3-sphere is a curved, finite 3-space, dimensionally analogous to the surface of the earth which is a curved, finite 2-space. This 3-sphere could be the domain of our visible cosmos, but of course we do not know for certain that all the cosmological objects we observe lie near the surface of our expanding 3-sphere, since it is only our assumption that they must all have originated in the same big bang long ago. Possibly some of the more distant objects we observe did not, and lie elsewhere, outside our big-bang's 3-sphere of outflying matter or even inside its 3-sphere, below its surface. We cannot assume that all objects in the 4-space universe lie near the surface of the same expanding 3-sphere. For all observers, the conjectured big-bang of their origin corresponds not only to a now-distant point in their proper time past, it also corresponds to a distinct now-distant point in 4-dimensional space: the same point in the same Euclidean 4-space for all observers with the same origin. Our big bang had a distinct origin point in real space as well as in real time. More generally, time and Euclidean 4-space can be measured independently, just as time and Euclidean 3-space were measured classically, without the necessity to combine them as spacetime. The same inertial force which holds the galactic cylinder of motion together also confines us physically to an exceedingly thin three-dimensional surface manifold moving through 4-space at velocity <math>c</math>. All objects in our solar system too small to have their own gravity lie entirely within this thinest three-dimensional manifold, and have only the thickness of an atom in their direction-of-motion fourth dimension. That is why we are 3-dimensional objects ourselves, and why we cannot construct more than three perpendiculars through a single point in our local 3-dimensional space. A spherical region of 4-space is called a [[W:4-ball|4-ball]]. The bounding surface of a 4-ball of any size is a finite, curved (non-Euclidean) 3-dimensional space called a [[w:3-sphere|3-sphere]]. Our entire big-bang-origin universe appears to be the largest 3-sphere we observe, but each of the cosmological objects within it (including our galaxy and our sun) is bounded by a smaller 3-sphere lying (we assume) on the largest 3-sphere embedded in its surface, like a soap bubble on the surface of a larger soap bubble. All the 3-dimensional surfaces are expanding, as the largest 3-sphere inflates at radial velocity <math>c</math>. We ourselves live within such an expanding 3-dimensional surface, in an infinitesimally curved 3-manifold surface embedded in Euclidean 4-space. That surface is the ordinary 3-dimensional space we experience. The earth and all the planets lie on it. Our solar system is only a small patch on the bounding surface of a dimensionally rounder space, although that surface is not infinite. It is curved, and finite, analogous to the way the 2-dimensional surface of the earth -- once thought to be flat -- is curved and finite. Our solar system occupies a small patch on a filmy 4-dimensional soap-bubble of galactic size rounded by gravity, that is thicker-skinned than the diameter of an atom only in the superdense interior of large gravitational objects. Our 3-manifold of ordinary space, as a surface within our moving 4-ball galaxy, is translating through 4-space at velocity <math>c</math> with the galaxy, in a distinct direction orthogonal to all three of our 3-manifold's dimensions of interior space. At every material point in the manifold (at every atom), the translation through 4-space is following a geometric law of motion discovered by Coxeter, that governs the propagation of individual objects through Euclidean space by the actions of their symmetry groups. The solar system's atoms of mass are 4-polytopes that are simultaneously rotating and translating, and as they advance together they define a moving 3-dimensional manifold by their own collective inertia, also called gravity, the property of matter's ceaseless propagation through 4-space at the constant velocity <math>c</math>, the universal rate of causality at which quantum events occur, all objects move, and the universe evolves. Any moving 3-dimensional manifold such as ours is an evolving surface boundary that is empty in most places, occupied by single atoms in comparatively fewer places, and occupied by bound complexes of multiple atoms (molecules) in still fewer places. In all these places it is no thicker than one atom in the dimension corresponding to its direction of translation, because molecules are 3-dimensional complexes of atoms that add no thickness to the manifold. In fewer places still it is occupied by large lumps of matter which exert a significant gravitational attraction, such as planets and their satellites. These round gravitational objects are thicker than one atom in their fourth dimension, but not uniformly so. They are disk-like 4-dimensional objects, 3-balls that are flattish in the fourth dimension. They are only one atom thick at the 4-disk's sharp edge, but they may be much thicker in the center of the 4-disk, if their gravity is strong enough to give them a core of superdense matter like the earth's deep core. The moving surface manifold cannot be thicker than one atom at any point unless and until there is enough mass near that point for the force of gravity as attraction to overcome the force of gravity as inertia, allowing atoms to be "heaped up" into larger 4-dimensional objects that form a lump in its moving surface. We have only indirect experience of such 4-dimensional lumps of matter thicker than one atom, since they occur naturally in our vicinity only in regions of superdense matter, such as the core of the earth or the interior of the sun. Deep in the core of the earth under enormous gravitational pressure peculiar states of matter have been observed, defying our understanding of how 3-dimensional crystalline structures behave. That is because they are not 3-dimensional structures, they are 4-dimensional crystals. The earth is a disk-like 4-dimensional object that is thin at its edge but thicker toward its center, dimensionally analogous to a 3-dimensional flying saucer with a sharp circular edge. The earth's surface that we walk on is an ordinary sphere (a 2-sphere), analogous to the circular edge of the flying saucer (a 1-sphere), and on that edge where we live every object we find (including our bodies) is 3-dimensional with only the thickness of an atom in the fourth dimension. We cannot walk on the top or bottom surface of the 4-disk flying saucer because those surfaces are 3-dimensional regions within the earth. The earth's deep core of superdense 4-dimensional matter occupies a spherical region of 4-dimensional space (a 4-ball). The sun is the only entirely spherical 4-ball occurring naturally in our solar system. We refer to the contents of such superdense 4-balls of matter as atomic plasma, and have little experimental knowledge of their internal geometry or processes. We know that the sun burns at its surface 3-sphere and emits radiation, and we know a good deal about those surface processes which are nuclear atomic processes, but we know very little about its interior 4-ball, a dimensionally rounder enclosed space whose existence we did not suspect. Every moving surface boundary of matter in the observed universe is evolving in four dimensions at velocity <math>c</math>. The current location in 4-space of any of its material objects corresponds to the present moment in the proper time of that object's inertial reference frame. The object's direction of movement at velocity <math>c</math> corresponds to its proper time dimension, which is a spiral over time, not a Euclidean (straight-line) dimension, since its direction is changing in its orbit. Objects with mass of all sizes, from subatomic particles to the largest objects observed in the cosmos, are perpetually in inertial rotational motion in some orbit, and simultaneously in inertial translational motion propagating themselves through 4-space, in two completely orthogonal inertial motions each at the constant universal rate of transformation <math>c</math>. Every free-falling object with mass moves relative to universal 4-coordinate Euclidean space on its own distinct geodesic spiral, a screw displacement trajectory that is the compound of its two completely orthogonal inertial motions at velocity <math>c</math>, a rotation and a translation. Objects without mass such as photons lie off such moving surface boundaries of matter from which they were emitted, and their motion is of a different nature. They are in translational motion at velocity <math>c</math> through all four dimensions concurrently, without any rotational component of motion, so they move through 4-space on straight lines at a compound velocity. The propagation speed of light measured on a straight line through Euclidean 4-space is <math>c\prime = 2c</math>, so we can see in four dimensions, even though we are physically confined to a 3-dimensional manifold that is moving at velocity <math>c</math>. For example, we can look across the center of the mostly-empty 4-ball containing our galaxy and see stars in the opposite sides of its concentric 3-sphere orbital surfaces. We have been unaware that when we look up at night we see stars and galaxies, themselves large 4-dimensional objects, distributed all around us in 4-dimensional Euclidean space, and moving through it, like us, at the constant velocity <math>c</math>. They move in the 4-space direction corresponding to their proper time, perpendicular to all three dimensions of their proper 3-space, and generally the farther they are from us the greater the divergence of their direction of motion from our direction of motion: the greater the relative motion between us, and the greater their Hubble redshift. Light from them reaches us directly, propagating on straight lines through 4-space at twice the velocity at which they, and we ourselves, are propagating through 4-space. This physical model of the observed universe is compatible with the theories of special and general relativity, and with the atomic theory of quantum mechanics. It explains those theories geometrically, as expressions of intrinsic symmetries in Euclidean space. == Symmetries == It is common to speak of nature as a web, and so it is, the great web of our physical experiences. Every web must have its root systems somewhere, and nature in this sense must be rooted in the symmetries which underlie physics and geometry, the [[W:Group (mathematics)|mathematics of groups]].{{Sfn|Conway, Burgiel & Goodman-Strauss|2008}} As I understand [[W:Noether's theorem|Noether's theorem]] (which is not mathematically), hers is the deepest meta-theory of nature yet, deeper than [[W:Theory of relativity|Einstein's relativity]] or [[W:Evolution|Darwin's evolution]] or [[W:Euclidean geometry|Euclid's geometry]]. It finds that all fundamental findings in physics are based on conservation laws which can be laid at the doors of distinct [[W:symmetry group |symmetry group]]s. Thus all fundamental systems in physics, as examples [[W:quantum chromodynamics|quantum chromodynamics]] (QCD) the theory of the strong force binding the atomic nucleus and [[W:quantum electrodynamics|quantum electrodynamics]] (QED) the theory of the electromagnetic force, each have a corresponding symmetry [[W:group theory|group theory]] of which they are an expression. [[W:Coxeter group|Coxeter's theory of symmetry groups]] generated by reflections did for geometry what Noether's theorem and Einstein's relativity did for physics. [[W:Coxeter|Coxeter]] showed that Euclidean geometry is based on conservation laws that correspond to distinct symmetry groups, and that their group actions express the principle of relativity. Here is Coxeter's formulation of the motions of objects (their congruent transformations) in an ''n''-dimensional Euclidean space, excerpted:{{Sfn|Coxeter|1973|pp=217-218|loc=§12.2 Congruent transformations}} <blockquote>Let <math>\mathrm{Q}</math> denote a rotation, <math>\mathrm{R}</math> a reflection, <math>\mathrm{T}</math> a translation, and let <math>\mathrm{Q}^q \mathrm{R}^r\mathrm{T}</math> denote a product of several such transformations, all commutative with one another. Then <math>\mathrm{RT}</math> is a glide-reflection (in two or three dimensions), <math>\mathrm{QR}</math> is a rotary-reflection, <math>\mathrm{QT}</math> is a screw-displacement, and <math>\mathrm{Q^2}</math> is a double rotation (in four dimensions).<br> Every orthogonal transformation is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r</math><br> where <math>(2^q + r \le n)</math>, the number of dimensions.<br> Transformations involving a translation are also expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}</math><br> where <math>(2^q + r + 1 \le n)</math>.<br> For <math>(n = 4)</math> in particular, every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> If we begin with this most elemental [[w:Kinematics|kinematics]] of Coxeter's, and also assume the [[W:Galilean relativity|Galilean principle of relativity]], every displacement in 4-space can be viewed as either a <math>\mathrm{Q^2}</math> or a <math>\mathrm{QT}</math>, because we can view any <math>\mathrm{QT}</math> as a <math>\mathrm{Q^2}</math> in a linearly moving (translating) reference frame. Therefore any transformation from one inertial reference frame to another is expressable as a <math>\mathrm{Q^2}</math>. By the same principle, we can view any <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> as an isoclinic (equi-angled) <math>\mathrm{Q^2}</math> by proper choice of reference frame.{{Efn|[[W:Arthur Cayley|Cayley]] showed that any rotation in 4-space can be decomposed into two isoclinic rotations, which intuitively we might see follows from the fact that any transformation from one inertial reference frame to another is expressable as a [[W:SO(4)|rotation in 4-dimensional Euclidean space]].|name=Cayley's rotation factorization into two isoclinic reference frame transformations}} Coxeter's relation is thus a mathematical statement of the principle of relativity, on group-theoretic grounds. It correctly captures the limits to [[W:General relativity|general relativity]], in that we can only exchange the translation (<math>\mathrm{T}</math>) for ''one'' of the two rotations (<math>\mathrm{Q}</math>). An observer in any inertial reference frame can always measure the presence, direction and velocity of ''one'' rotation (<math>\mathrm{Q}</math>) up to uncertainty, and can always distinguish the direction of their own proper time translation (<math>\mathrm{T}</math>). As I understand Coxeter theory (which is not mathematically), the symmetry groups underlying physics seem to have an expression in a [[W:Euclidean space|Euclidean space]] of four [[W:dimension|dimension]]s, that is, they are [[W:Euclidean geometry#Higher dimensions|four-dimensional Euclidean geometry]]. Therefore as I understand that geometry (which is entirely by synthetic methods rather than by [[W:Geometric algebra|Clifford's algebraic methods]]), the [[W:Atom|atom]] seems to have a distinct Euclidean geometry, such that atoms and their constituent particles are four-dimensional geometric objects (4-polytopes), and nature can be understood in terms of their [[W:group action|group actions]], including centrally their group <math>SO(4)</math> [[W:rotations in 4-dimensional Euclidean space|rotations in 4-dimensional Euclidean space]]. The distinct Coxeter symmetry groups have characteristic <math>SO(4)</math> rotational expressions as the [[W:Regular_4-polytope|regular 4-polytopes]]. Their discrete isoclinic rotations are distinguishing properties of fundamental objects in geometry, relativity and quantum mechanics. == Special relativity describes Euclidean 4-space == <blockquote>Our entire model of the universe is built on symmetries. Some, like isotropy (the laws are the same in all directions), homogeneity (same in all places), and time invariance (same at all times) seem natural enough. Even relativity, the Lorentz Invariance that allows everyone to observe a constant speed of light, has an elegance to it that makes it seem natural.<ref>{{Cite book|first=Dave|last=Goldberg|title=The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality|chapter=§10. Hidden Symmetries: Why some symmetries but not others?|year=2013|publisher=Dutton Penguin Group|isbn=978-0-525-95366-1|ref={{SfnRef|Goldberg|2013}}}}</ref></blockquote> Although the Minkowski spacetime of relativity is a non-Euclidean 4-dimensional space,{{Efn|Spacetime is a non-Euclidean (curved) 4-dimensional space because it consists of three orthogonal space dimensions and a time dimension. The time dimension is not orthogonal to the three spatial dimensions; the time coordinate has the opposite sign as the three space coordinates so spacetime is hyperbolic, not a Euclidean (flat) 4-space at all.}} it has been noticed that its 3-dimensional space component could be modeled as a [[W:3-sphere|3-sphere]] embedded in 4-dimensional Euclidean (flat) space. That is, we could imagine that the ordinary 3-dimensional space we perceive is the curved 3-dimensional surface of a 4-dimensional ball (since the surface of a 4-ball is a curved 3-dimensional space called a 3-sphere, just as the surface of a 3-ball like the earth is a curved 2-dimensional space called a 2-sphere). This was [[#Origins of the theory|imagined by Einstein]] himself in 1921, as a thought experiment in which he carefully described his fourth orthogonal spatial dimension as merely a mathematical abstraction.<ref name=Einstein1923>{{Cite book|url=http://www.gutenberg.org/ebooks/36276|title=The Meaning of Relativity|last=Einstein|first=Albert|publisher=Princeton University Press|year=1923|isbn=|location=|pages=110-111}}</ref> Subsequently it was noticed by others (not mainstream physicists) that if physical space were really embedded in Euclidean 4-dimensional space (with our 3-dimensional space embedded in 4-space as some non-Euclidean 3-manifold, not necessarily a 3-sphere), then the Lorentz transformation effects of special relativity (spatial forshortenings and time dilations and so forth) could all be explained by ordinary perspective geometry in 4-dimensional Euclidean space. Special relativity reduces to classical vector space geometry (based on the 4-dimensional version of the Pythagorean theorem), but if and only if every observer is moving through 4-space at a universal constant velocity <math>c</math>, in some 4-space direction.{{Sfn|Yamashita|2023}} This counter-intuitive alternative geometric model of relativity, which has usually been called [[W:Formulations of special relativity#Euclidean relativity|Euclidean relativity]], is motivated by the fact that in every kind of relativity, but originally in Einstein's special relativity, each observer moves on a vector through a Euclidean four-dimensional space consisting of their three proper spatial dimensions and their proper time dimension, and the Pythagorean vector-sum of their motion through this kind of proper 4-space is always <math>c</math>, as measured by all observers from any inertial reference frame.{{Efn|Each observer is stationary in space in their own proper reference frame, while they move at maximum velocity {{Math|c}} through their own proper time. Observed from another reference frame in relative motion, they appear foreshortened in space in their direction of motion, and their clocks appear to be slowed to less than the maximum velocity {{Math|c}}.}} This is the Lorentz invariant, that allows everyone to observe a constant speed of light, regardless of their motion relative to the light source.{{Efn| ...cite Lewis Epstein's elegant explanation of the Lorentz Invariance as observers moving at constant velocity {{Math|c}} through space and proper time.}} But no physicists have taken the leap of claiming that therefore, our universe is physically [[W:Euclidean geometry#Higher dimensions|this kind of Euclidean 4-space]], and that observers are actually moving through it at velocity <math>c</math>. In physics as it has been universally understood, observers are not supposed to be able to move at velocity <math>c</math>. Their motion takes place in 3-space and in universal coordinate time (in Minkowski spacetime), and the cosmos is considered to be a non-Euclidean 3-space, generally a closed (finite) expanding 3-space, but with only three spatial dimensions, not four. In the Euclidean relativity alternative view, however, every observer is always moving at velocity <math>c</math> through the universe, which is real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. The direction in which they are moving is called their proper time axis.{{Efn|Time in spacetime is universal coordinate time, but there is another kind of time in relativity, the proper time in each inertial reference frame. Your proper time is the time you experience, and every observer has his own proper time; proper time runs at different rates in different inertial reference frames. It runs slower (compared to universal coordinate time) in a gravitational field (according to general relativity), and observers in motion with respect to each other view each other's clocks as running slower than their own clocks (according to special relativity).}} Their movement in time is not just modelled as movement in an abstract fourth dimension (as it is in Minkowski spacetime), their movement in time is isomorphic to their movement through physical space in a distinct direction at velocity <math>c</math>. Two observers' directions of movement through space may be different (or not, if they happen to be going in the same direction). Your proper time dimension is whichever direction you are moving. The other three directions perpendicular to your proper time axis are the three dimensions of your ordinary proper space, which again, will be different directions for you than for other observers moving in a different direction. There are four orthogonal spatial dimensions which we all share, but we share the same orthogonal proper time axis and ordinary proper 3-space axes only if we are at rest with respect to each other, actually moving in the same direction at velocity <math>c</math>, in the same inertial reference frame. Your proper 4-space coordinate system is rotated with respect to another observer's proper 4-space coordinate system, precisely as your vectors (directions of motion) are rotated in Euclidean 4-space with respect to each other, but there are no metric distortions (no Lorentz transformations) between your proper Euclidean 4-space coordinate systems; you are both embedded in the same Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. Lorentz transformations are required only to convert between your respective proper Minkowski spacetime coordinate systems. So in this novel alternate view of relativity, every mass in the universe must be perpetually in motion at velocity <math>c</math> through Euclidean 4-space, along with all the masses in its vicinity that are going in (nearly) the same direction. The entire solar system, for example, must be translating in the fourth dimension at the "speed of light" <math>c</math>, although we do not notice it, since we are all moving in that same direction together. Acceleration of an object varies its direction of motion through 4-space, but never its velocity, which is invariant for all objects with mass. Two objects which are in motion relative to each other are both actually in motion at the same velocity <math>c</math>, but in at least slightly different directions.{{Efn|The angular divergence between two observer's motion vectors is proportional to their relative velocity: the more they diverge, the greater their relative velocity, up to the maximum divergence possible in the space. In Euclidean relativity all observers are in motion at velocity {{Math|c}} relative to universal Cartesian 4-coordinate space, so the maximum relative velocity between two observers is {{Math|2c}} when they are moving in exactly opposite directions in 4-space. This is not a contradiction of special relativity, which limits the maximum relative velocity between two observers to {{Math|c}}, it is the same measurement in different units. Special relativity measures all velocities in Minkowski spacetime (in a non-Euclidean 3-space). Euclidean relativity measures all velocities in Euclidean 4-space.}} In Einstein's relativity, the invariant <math>c</math> is the speed of light through 3-space. In Euclidean relativity, the invariant <math>c</math> is the speed of matter through 4-space! The speed of light through 3-space is also perceived as <math>c</math> by all observers, because they are each living in a moving 3-manifold that is translating through 4-space at velocity <math>c</math>. Despite their extreme differences in viewpoint, Einstein's relativity and Euclidean relativity are equivalent theories in complete agreement with each other, by definition. The two theories make exactly the same special relativity predictions of how observers in different inertial reference frames will perceive each other's motions in time and space. It is beyond the scope of this present paper to show how they also agree on the predictions of general relativity, but it is important to understand that our formulation of Euclidean relativity requires our acceptance of the experimentally verified findings of special relativity, general relativity and quantum mechanics. Our model and the standard model both describe the same geometric relations of space and time based on the same evidence, but as embedded in two very different universal host spaces: Euclidean 4-space versus Minkowski spacetime. In some instances our model provides a geometric explanation for physical phenomena where the standard model has none, as yet. An example is the two models' differing explanations for the gravitational coherence of galaxies: either their inertial motion at velocity <math>c</math>, or their possession of experimentally undetected dark matter. A more central example is our use of Coxeter's kinematics to explain the laws of relativistic motion geometrically. {{Efn|More generally, our model is concerned with group-theoretic properties of number elucidated by Coxeter and other geometers. ...cite Kappraff & Adamson's 2003 paper on The Relationship of the Cotangent Function to Special Relativity Theory, geometry and properties of number,{{Sfn|Kappraff & Adamson|2003|loc=Special Relativity Theory, Geometry and properties of number}} which shows how the Lorentz coefficient is a function of a deep geometric property of number{{Sfn|Kappraff & Adamson|2000|loc=A Fresh Look at Number}} discovered by Steinbach,{{Sfn|Steinbach|1997|loc=Golden Fields: A Case for the Heptagon}} by means of which the root formula of geometry in any Euclidean dimension, the Pythagorean theorem, may be derived solely in terms of the addition of polygon side lengths, without recourse to their products or squares. More generally, Steinbach found that in the relations among regular polytope chords, to add is to multiply; every chord is both the product (quotient) of a pair of chords and the sum (difference) of another pair of chords.}} Euclidean relativity is not even a fringe theory; no physicists or astronomers have adopted it. There are many good reasons why the revolutionary leap to a four orthogonal spatial dimensions viewpoint has not been taken, beginning with the universally observed fact that we can only construct three perpendiculars through a point in our immediate space, which appears to be resolutely 3-dimensional, not 4-dimensional. Euclidean relativity offers a nice geometric explanation of the reasons for the Lorentz transformations, but only at the cost of raising other mysteries, which have been difficult for its aficionados to explain. Another mystery is how light signals between observers in relative motion could "catch up" with the receiver moving on a diverging path through 4-space from the emitter. If both observers are already moving at <math>c</math> (on diverging paths), the propagation speed of light through 4-space between them would have to be greater than <math>c</math>. Euclidean relativity is a revolutionary theory indeed, in which <math>c</math> cannot possibly be the speed of light! We conclude that, for a theory of Euclidean 4-space to be physically viable (that is, for <math>\mathbb{R}^4</math> to be our real space and not merely an abstract mathematical space), the speed of light through Euclidean 4-space must be <math>c\prime = 2c</math>, with massless photons translating through 4-space at twice the speed of mass-carrying objects. Photons must translate the diagonal distance through 4-space along the long diameter of a unit 4-hypercube, in the same time that massive particles translate inertially along the edge (or the radius) of a unit 4-hypercube. This is conceivable in Euclidean 4-space (and in no other Euclidean space of any dimensionality) because the long diagonal of the unit 4-hypercube is the natural number <math>\sqrt{4}</math>. == An object's motion in space is the local product of its discrete self-reflections == Coxeter theory describes all the possible motions of an object in space as local functions of the object's discrete geometry (its shape). Coxeter observed that in a Euclidean space of any number of dimensions, any displacement of a geometric object from one place to another, and any rotation of the object from one orientation to another, can be broken down into the product of a number of discrete self-reflections. Any action of a polytope that transforms its position and orientation in space may be measured as a distinct sequence of self-reflections of the object in its own mirror surfaces. Therefore any motion of the object whatsoever may be precisely described as the object propagating itself through space by a discrete sequence of local self-reflections. This is a purely kinematic description of motion which does not give any account of forces acting on the object that cause it to move. Coxeter found that both changes in position (translations) and changes in orientation (rotations) can be broken down into the simplest of all displacements (self-reflections). A translation occurs when an object self-reflects twice, in two distinct mirror surfaces which are parallel to each other. A rotation also occurs when an object self-reflects twice, but in two distinct mirror surfaces which intersect each other. When a object self-reflects once, it turns itself inside out (it reverses its chirality), but in translations and rotations it self-reflects twice, preserving its chirality. Coxeter's laws of kinematics are a geometric counterpart to Newton's algebraic laws of motion in three dimensional Euclidean space. They are helpful because they can be understood as geometric pictures, which may help us to visualize the relationships between translation and rotation in classic Newtonian physics problems, such as the [[W:Kepler problem|Kepler problem]] of the motion of the planets. But they are also a revolutionary advance beyond Newton's laws, because Coxeter formulated them in Euclidean spaces of any number of dimensions. In particular, they give us geometric pictures of all the possible motions of objects in 4-dimensional Euclidean space: <blockquote>Every orthogonal transformation in 4-space is expressible as:<br> :<math>\mathrm{Q}^q \mathrm{R}^r \mathrm{T}^t</math><br> where <math>(2^q + r + t \le 4)</math>. Every displacement is either a double rotation <math>\mathrm{Q}^2</math>, or a screw-displacement <math>\mathrm{QT}</math> [where the rotation component <math>\mathrm{Q}</math> is a simple rotation, but the <math>\mathrm{QT}</math> is chiral like a <math>\mathrm{Q^2}</math>]. Every enantiomorphous transformation in 4-space (reversing chirality) is a <math>\mathrm{QRT}</math>.</blockquote> While this description should be understood as geometric pictures, some of the pictures may not be easy for us to visualize, since we have no physical experience in 4-dimensional space. Rotation (<math>\mathrm{Q}</math>), reflection (<math>\mathrm{R}</math>) and translation (<math>\mathrm{T}</math>) are direct dimensional analogues of what they are in three-dimensional space, but double rotation (<math>\mathrm{Q}^2</math>) is something new and unprecedented in our physical experience, because double rotations cannot occur until there are four or more dimensions of space in which to rotate. Four dimensional Euclidean space can accomodate no such thing as a <math>\mathrm{Q}^2\mathrm{T}</math>. A translating double rotation <math>\mathrm{Q}^2</math>, like a translating simple rotation <math>\mathrm{Q}</math>, is simply a screw translation <math>\mathrm{QT}</math>. That is the essence of the way the principle of relativity operates in Euclidean 4-space. An object which is double-rotating in its own proper inertial reference frame may be seen to be performing nothing more mysterious than a screw translation, when observed from an inertial reference frame from which the object is in relative translational motion. Of course, it is a screw translation in 4-space, which is more mysterious than a screw translation in our ordinary 3-space. In 3-space the orbit of a screw translation <math>\mathrm{QT}</math> or a simple rotation <math>\mathrm{Q}</math> lies on a great circle of an ordinary sphere (a 2-sphere), translating or stationary. In 4-space the orbit of a screw translation <math>\mathrm{QT}</math> or double rotation <math>\mathrm{Q}^2</math> lies on a great circle of a hypersphere (a 3-sphere), translating or stationary. Rotational great circles on hyperspheres are inherently more complex than the ordinary great circles on spheres we experience in 3-space. A point on the surface of an object rotating in 4-space may be in motion on two circles, in two [[W:Completely orthogonal|completely orthogonal]] rotation planes simultaneously. As each planar circle rotates like a wheel turning, its rotation plane also tilts sideways like a coin flipping, eventually into the completely orthogonal original rotation plane of the other circle, so that the circles have exchanged rotation planes. The product of these two simultaneous completely orthogonal circular motions gives a circular orbit to each moving point that does not lie in any stationary rotation plane; it is a circular helix that bends in all four dimensions rather than in just two dimensions, in either a left or right hand direction of helical curvature. Unlike ordinary planar circles, these 4-dimensional circles are inherently chiral, and their circumference is not <math>2\pi r</math>. But like ordinary planar great circles they are true geodesic circles. They may even be understood as dimensionally more circular than ordinary circles, which bend in only two dimensions. We refer to such 4-dimensional great circles as ''isoclines'', to distinguish them from ordinary 2-dimensional great circles in the plane. Their name comes from the fact that a point on a rigid 4-dimensional object undergoing [[W:SO(4)#Isoclinic rotations|isoclinic rotation]] traverses an isocline circle. In our universe which is real Euclidean four-dimensional space <math>\mathbb{R}^4</math>, these motions occur only at the constant velocity <math>c</math>, and there is a universal Cartesian 4-coordinate reference frame in which every rigid object in free fall is translating on a <math>\mathrm{QT}</math> at velocity <math>c</math>. That universal inertial reference frame is not the proper reference frame of any object or observer, wherein the object or observer is stationary and double-rotating, but it is a common reference frame of all observers. == Light propagates through 4-space at twice its apparent velocity <math>c</math>== Coxeter's laws of kinematics in 4-dimensional Euclidean space enumerate all possible displacements of objects with mass. We find there is an additional kind of displacement which applies only to massless particles such as photons. Light quanta (photons) translate through 4-space by 4-dimensional reflection <math>\mathrm{R}^4</math>, which may be seen as a double translation <math>\mathrm{T}^2</math>, a pure translation via two pairs of parallel reflections without any rotation component <math>\mathrm{Q}</math>. Objects with mass of any size (including atoms and their subatomic particles) are perpetually rotating and translating through 4-space by <math>\mathrm{QT}</math>, a screw translation of a rotating object, which is relativistically equivalent to a stationary isoclinic <math>\mathrm{Q^2}</math>, such as an atom in its own proper reference frame. A simple rotation <math>\mathrm{Q}</math> or simple translation <math>\mathrm{T}</math> is a double reflection <math>\mathrm{R^2}</math>, so a <math>\mathrm{QT}</math> or <math>\mathrm{Q^2}</math> is an <math>\mathrm{R^4}</math>, but not with the same group of reflection angles as a light signal <math>\mathrm{R^4}</math>. 2-dimensional objects reflect in a line, 3-dimensional objects reflect in a plane, and 4-dimensional objects reflect in a hyperplane (a 3-dimensional mirror). A translation <math>\mathrm{T = R^2}</math> is a double reflection in two parallel hyperplanes, and a rotation <math>\mathrm{Q = R^2}</math> is a double reflection in two intersecting hyperplanes, as in a <math>\mathrm{QT = R^4}</math> which is both at once. A double translation <math>\mathrm{T^2 = R^4}</math> is two double reflections in two pairs of parallel hyperplanes at once, a reflection in four hyperplane mirrors; it is all translation and no rotation. All the motion goes to translation, so the displacement goes twice as far as the simple translation <math>\mathrm{T}</math> in a <math>\mathrm{QT}</math>. A double translation <math>\mathrm{T^2 = R^4}</math> is the opposite of a double rotation <math>\mathrm{Q^2 = R^4}</math>, which is stationary but rotates twice as far as the simple rotation <math>\mathrm{Q}</math> in a <math>\mathrm{QT}</math>. The product of the two translations in a <math>\mathrm{T^2}</math> is a diagonal 4-space translation over the long diameter of the unit 4-hypercube, exactly twice the distance of a simple <math>\mathrm{T}</math> over the edge length (or radius) of the unit 4-hypercube. The [[w:Tesseract|4-hypercube (also known as the 8-cell or tesseract)]] is ''radially equilateral'', which means its edge length is equal to its radius, like the hexagon, so its long diameter (twice its radius) is exactly twice its edge length. The photon moves an equal distance in four orthogonal directions. By the four-dimensional Pythagorean theorem, each of those four distances is half the total distance the photon moves: one edge length (one radius) is half the total diagonal distance moved (the long diameter). That total movement is a double the unit-distance translation, but without any rotation component, so it cannot carry any mass with it. A <math>\mathrm{T^2}</math> cannot reposition a 4-polytope the way a <math>\mathrm{QT}</math> does, it can only reposition a quantum of energy that has no distinguishing rotational symmetry, such as a photon. That is the price light pays to move exactly twice as fast as matter.{{Efn| ...lensing of double translations <math>\mathrm{T^2 = R^4}</math> in more than two pairs of parallel planes at once...relationship to the frequency of light emitted and the coherence length of the wave packet...}} == Special relativity is Galilean relativity in Euclidean 4-space == Perspective effects known as the Lorentz transformations occur because each observer's proper 3-dimensional space is a moving curved 3-manifold embedded in flat Euclidean 4-space. The motion and curvature of their proper 3-space complicates sightline calculations for observers; they require Lorentz transformations to produce their 3-coordinate Cartesian coordinates of objects in the scene being observed. But if all four spatial dimensions are considered, no Lorentz transformations are required (or permitted) in correct scene construction in 4-coordinate space. Lorentz transformations are needed only when an observer wants to calculate a projection, that is, the shadow in a 3-coordinate space of how things will appear as a 3-dimensional scene (not how they really are in 4-space).{{Sfn|Yamashita|2023}} Space really has four orthogonal dimensions, and space and time behave there exactly as they do in a classical vector space, but bigger by one dimension. It is not necessary to combine 4-space with time in a unified spacetime to explain 4-dimensional perspective effects at high relative velocities, because Euclidean 4-space is already 4-dimensional, and those effects fall out naturally from the 4-dimensional Pythagorean theorem, exactly as ordinary visual perspective does in 3-space from the 3-dimensional Pythagorean theorem. Because one of the four spatial dimensions corresponds to an observer's direction of motion (in both space and proper time) at velocity <math>c</math>, and all observers and all scenes being observed are in motion (at this constant velocity) in their respective proper time directions, we observe perspective forshortenings in time as well as in one of our three spatial dimensions. In special relativity these perspective effects are reciprocal, precisely because they are only apparent, not actual, changes in size and duration. (However in general relativity, discussed below, the actual rate of all physical processes varies from field to field, and reference frame differences predicted by the theory are not reciprocal.) The Lorentz invariant of special relativity allows everyone to observe a constant speed of light, regardless of their motion relative to the light source. In Euclidean relativity we are able to state this intrinsic symmetry of nature more simply: <blockquote>Time ticks at the same rate everywhere in space.</blockquote> This formulation of special relativity at first appears to contradict general relativity, which insists that time (in the sense of the quantum rate of all physical processes) ticks more slowly deeper in a gravitational field. We shall see (below) that there is no contradiction between the universal rate of time at every place in space, and the relative rates of time in distinct gravitational fields, because in the Euclidean relativity formulation all gravitational fields are in motion. A gravitational field is not a place; it is better described as a state of motion of a set of objects, in particular their states of acceleration. As the objects are in perpetual motion, so also is their field. General relativity predicts differences in the rates at which clocks run in distinct moving gravitational fields, and special relativity predicts differences in perceived rates at which clocks run in distinct moving inertial reference frames, but we shall see that none of these differences imply that time (in the sense of the quantum rate of change) ever runs at any rate other than <math>c</math> in any stationary place in 4-space, at any time. None of the special relativity Lorentz effects (or as we shall see the general relativity effects) are beyond geometric explanation or paradoxical, but their geometric explanation requires Euclidean 4-space. The universe is unexpectedly strange to us in precisely the ways the Euclidean fourth dimension is strange to us; but that does hold many surprises. Euclidean 4-space is much more interesting and revealing than Euclidean 3-space, analogous to the way our 3-space is more deeply explanatory to us than it would be if we experienced it only as a 2-space with many folds and curves, as perhaps an ant does. The emergent properties of 4-space are hard for us to visualize because they lie so wholly beyond our physical experience, just as it was hard for our ancestors to imagine the earth as round like a ball. However, Euclidean spaces of successive dimensions are strictly analogous, and so higher dimensional spaces can be anticipated and explored: that is Schläfli's great discovery. Moreover dimensional analogy itself, like everything else in nature including all of physics, is a strict expression of relations between intrinsic group-theoretic symmetries: that is Noether's and Coxeter's great discovery. == General relativity is the geometry of gravity in Euclidean 4-space == The statement that the laws of special relativity hold to good approximation in freely falling (and non-rotating) reference frames is known as the [[W:Equivalence principle|Einstein equivalence principle]]. The weight experienced by an observer standing on the floor in a building on the surface of the earth is the same as the weight experienced by an observer standing on the floor in a spaceship in interstellar space accelerating at a rate of 32'/second/second. Both observers are experiencing an upwards acceleration at the same rate, which in their respective proper reference frames is measured as the weight of gravity, rather than as an accelerating motion (they are stationary in their proper reference frames). Einstein used this equivalence principle as the basis for his general theory of relativity, in much the same way he had used the constant velocity of light as the basis for his special theory of relativity. In general relativity the two accelerating observers occupy scenes which are relativistically equivalent, which means that although they can be distinguished (they have different measurements) in any reference frame from which they may both be observed, they have the same invariant geometry in all reference frames (they are the same phenomena), implying that there exists, for either scene, another reference frame from which it measures exactly like the other scene. Relativistically equivalent does not imply that there exists a single reference frame in which the two scenes are congruent (have the same measurements). It only means that they can be transformed into each other by a shift in point of view, because their invariant geometries (their measurements which are independent of point of view) are the same. Einstein's general theory of relativity describes that invariant geometry, for scenes in general, in spacetime. Our formulation of Euclidean relativity describes that invariant geometry, for scenes in general, in real Euclidean 4-dimensional space <math>\mathbb{R}^4</math>. An observer standing on the surface of the earth is accelerated at the rate of 32'/second/second. The observer and the earth are both stationary in their proper inertial reference frames (which are similar except for the rotation of the earth), so the observer's acceleration cannot be perceived as motion in either proper reference frame; it is perceptible there instead as the force of gravity. It is only perceptible as motion in some other reference frame in which the earth and the observer are both in motion, such as the universal common reference frame of Euclidean 4-coordinate space in which they are both in motion at velocity <math>c</math> on their respective distinct screw translations <math>QT</math>. In that universal common reference frame the observer's acceleration of 32'/second/second is the rate of change in the direction of his vector of translation <math>T</math> through 4-space. The velocity of that vector remains the constant <math>c</math> throughout; only his direction is changing. A change in the direction of a vector is a rotation <math>Q</math> of a translation <math>T</math>: a screw translation <math>QT</math>. A change in the direction of a vector is a rotation which is an acceleration. We can be precise about the units of measurement of this acceleration at atomic scale. In Coxeter's kinematics rotations of geometric objects occur in discrete increments called rotational displacements, with each distinct kind of rotation composed of a discrete number of its characteristic rotational displacement in each full revolution that returns the object to its starting orientation. There are many distinct kinds of rotation, each with its characteristic rotational displacement and discrete number of displacements per revolution. The general rotation in 4-space is a double rotation <math>Q^2</math> distinguished by two completely orthogonal angles through which the object turns in each rotational displacement. The angles determine not only the distance through which the object turns, but the characteristic trajectory of each point on the bounding surface of a rotating object, including the length of that trajectory before it closes into a circle when the object returns to its starting orientation. For any distinct kind of rotation, the circular trajectory is always an integer multiple of the characteristic rotational displacement, but the full circle may have to be greater than 360° to close a circular revolution. In 4-space rotational circles are not ordinary 2-dimensional circles that lie in the plane and have a 360° circumference, they are chiral 4-dimensional circles which we call isoclines. Many distinct 4-space rotations of interest have isoclines of 720° circumference. In 4-space every object with mass moves on its distinct <math>QT</math> trajectory. Each rotational displacement <math>Q</math> is equivalent to a pair of reflection displacements in two mirror surfaces which intersect each other, at angles related to a distinct star polygon. Each translational displacement <math>T</math> is equivalent to a pair of reflection displacements in two mirror surfaces which lie parallel to each other. In both kinds of motion (rotation and translation) it is the rate at which these double-reflection displacements occur which is constant and which we measure as the velocity <math>c</math>. Every atom translates at velocity <math>c</math>, performing a large number <math>c</math> of atomic scale translational displacements per second. Concurrently, the atom rotates at velocity <math>c</math>, performing the same large number <math>c</math> of atomic scale rotational displacements per second. Although the number of displacements at atomic scale per unit time is the same universal constant <math>c</math> for all rotations and translations, distinct kinds of rotation revolve at distinct rates, because the number of rotational displacements per complete revolution, and the circumference of the complete revolution, are characteristics of each kind of rotation. The velocity at which each point on the surface of a rotating object moves, and the frequency of its rotational circling, are functions of the distinct rotation it is performing. However, they are not simple functions of <math>c</math> and the two defining angle parameters of the rotation, since they depend on the geometry of the rotational isocline which is unique to the distinct rotation. Distinct rotations arise from distinct symmetry groups, which are each their own mystery with a unique conservation law and set of rotations. The unique geometry of each rotation's isocline is that of some distinct star polygon. The geometric relationships between star polygons defined by successive rational numbers are mathematically mysterious, and have been shown to be chaotic. Steinbach{{Sfn|Steinbach|1997}} discovered the Golden Fields family of ratios, which govern distinct rotational displacements related to the regular star polygons at least up to the hendecagon {11}. Kappraff and Adamson{{Sfn|Kappraff|Adamson|2004}} further characterized the families of rotation functions, and showed that they form an infinite number of periodic trajectories when operated on by the Mandelbrot operator. The inertial tendency of mass is to follow a geodesic. The inertial conservation law of gravity applies to all motions of objects with mass, rotations as well as translations, because a translation <math>T</math> is the distinct simple rotation <math>Q</math> in which the characteristic angle of rotational displacement is 180°. Inertia is the tendency of objects with mass to conserve their angles of rotational displacement. In 4-space each object has two completely orthogonal angles of rotational displacement which are characteristic of the distinct rotation the object is performing, and inertia is the conservation of this distinct double rotation. The acceleration of an object with mass is a rotation of the object, a change to its direction, not a change to its constant velocity <math>c</math>. Because the rate of atomic scale displacement events is the universal constant <math>c</math>, the rate of change of direction (the acceleration of the object) is a function of <math>c</math> and the distinct rotation's isocline geometry. General relativity explains gravity geometrically as a non-Euclidean geometry in spacetime that is more complex than special relativity's non-Euclidean Lorentz geometry in spacetime. In Euclidean 4-space the geometry of special relativity becomes simpler Euclidean geometry, dimensionally analogous to familiar perspective geometry in ordinary Euclidean 3-space, and therefore visualizable provided we can stretch our dimensional analogy muscles enough to imagine perspective views in four orthogonal spatial dimensions. A similar stretch is required of us to visualize general relativity in Euclidean 4-space: we must imagine distinct rotations in four spatial dimensions. To understand gravity geometrically in four dimensions, we must identify the distinct rotation the accelerating observer is performing, visualize its isocline, and model its unique conservation law geometrically as motion on those isoclines in Euclidean 4-space.{{Efn|It will also help to visualize the isocline as a geodesic straight line in spherical 3-dimensional space, on the surface of the 3-sphere.}} That problem is dimensionally analogous to the problem that Kepler and Newton solved for the rotation of the planets in Euclidean 3-space.<ref>{{Cite book|last=Feynman|first=Richard|title=Feynman's Lost Lecture: The Motion of Planets Around the Sun|date=1996|publisher=W. W. Norton & Company|isbn=978-0393039184}}</ref> It is a [[W:Kepler problem|Kepler problem]], hosted in Euclidean 4-space. A observer standing on the surface of the earth is performing a distinct double rotation characterized by two completely orthogonal angles of rotational displacement. The observer's acceleration of 32'/second/second is a function of <math>c</math> and the distinct rotation's isocline geometry, yielding a measurement of the rate of change of the observer's direction of motion through 4-space at velocity <math>c</math>. Our challenge is to visualize this double rotation. ... == Quantum mechanics is the rotational kinematics of Coxeter groups in Euclidean 4-space == Atoms are 4-polytopes, small round 4-dimensional objects, and their rotational symmetry is compounded from that of the [[Polyscheme#Regular convex 4-polytopes|six regular convex 4-polytopes]]. Their geometry is beyond the scope of this paper, but we begin with the proton, which we identify with the rotational symmetry of the 4-simplex polytope. Schläfli discovered that there exists a compound series of six regular convex 4-polytopes, dimensionally analogous to the compound series of five regular convex 3-polytopes, the Platonic solids. Polytopes in each series are naturally ordered by size, as a measure of content for the same radius, which is also a measure of their roundness, the number of their vertices. They form a series of increasingly round polytopes in which each is a compound of multiple instances of its predecessor (with one exception to this progression which will concern us later). The six regular convex 4-polytopes have 5, 8, 16, 24, 120, and 600 vertices respectively. They are the 5-point (5-cell) 4-simplex, the 8-point (16-cell) 4-orthoplex, the 16-point (8-cell) 4-hypercube, the 24-point (24-cell), the 120-point (600-cell), and the 600-point (120-cell). The smallest (least round) regular convex 4-polytope is the [[5-cell|4-simplex]]. It has 5 vertices, 10 edges, 10 triangular faces, and 5 tetrahedral cells. The regular 4-simplex is the configuration of 5 mutually equidistant points in Euclidean space, on the surface of a 3-sphere. We identify the proton with the rotational symmetry the 4-simplex. The largest (roundest) regular convex 4-polytope is called the [[120-cell|120-cell]]. It has 600 vertices and 1200 edges, because it is a regular compound of 120 completely disjoint 4-simplexes, rotated isoclinically with respect to each other such that their vertices are evenly distributed on the surface of a 3-sphere. It is also a regular compound of every other regular convex 4-polytope, so that instances of every regular convex polytope which can exist in Euclidean 4-space are found within it. It is the singular geometrically comprehensive 4-polytope, containing instances of the relationships among all these polytopes. The exception to the rule that each 4-polytope in the series compounds to its successor is the 5-point 4-simplex, which does not compound to its successor the 8-point 4-orthoplex, nor to any other 4-polytope in the series except the largest, the 600-point 120-cell. None of the 4-polytopes in the series are divisible into an integral number of 4-simplexes except the 120-cell. Every 4-polytope in the series except the 4-simplex is divisible into an integral number of 4-orthoplexes. Thus there are two alternate integral building blocks of the comprehensive 120-cell: the 5-point 4-simplex, and the 8-point 4-orthoplex. Only the 4-orthoplex will build the other three 4-polytopes in the series by simple compounding. However, the symmetry group of the 4-simplex also has a foundational relationship to the symmetries of all the 4-polytopes in the series. If we view the 4-simplex as the largest 4-polytope instead of the smallest, and subdivide it by integral truncation, we find smaller instances of all the other 4-polytopes within it. The nucleus of a distinct atomic element contains a characteristic number of protons, its atomic number. The rotational symmetry of each atomic nucleus is based on that of a compound of its distinct number of completely disjoint 4-simplex polytopes, that is, on the symmetry of a sparsely populated 120-cell. Because only 120 4-simplexes will fit into a 120-cell, each occupying exclusively 5 equidistant vertices of the 600 vertices, only 120 distinct atomic elements are possible. Any compound of the atomic number of 4-simplexes constitutes an atomic nucleus of that element, but multiple geometric configurations of each element are possible, depending on which subset of 4-simplex positions is populated. Some of these configurations will have more symmetry than others. We conclude that these alternate configurations potential nuclides of the atomic element, some potentially more stable than others. We identify the neutron with the rotational symmetry of the 8-point 4-orthoplex. Our conjecture is that each nuclide is a sparse configuration of the 120-cell that contains its atomic number of 4-simplexes and its neutron number of 4-orthoplexes. The 8-point 4-orthoplex is the easiest 4-polytope to visualize because it consists simply of 4 pairs of opposing vertices on 4 orthogonal axes. It is the [[W:Orthonormal basis|orthonormal basis]] polytope, because its size, location and orientation in 4-space defines a Cartesian (w,x,y,z) coordinate basis, a non-rotating inertial reference frame. Every 4-polytope in the series of six except the 4-simplex is divisible into an integer number of disjoint 4-orthoplexes, each occupying exclusively 8 of the 600 vertices of the 120-cell. Moreover, both the 120-point 600-cell and the 600-point 120-cell are divisible into a larger integer number of non-disjoint 4-orthoplexes which share axes. In contrast, the 5-point 4-simplex is the only regular convex 4-polytope with vertices that do not occur in opposing pairs. It is impossible to position two 4-simplexes on the 3-sphere such that they share some, but not all 5 vertices. Therefore the 600-point 120-cell can only be partitioned into 120 disjoint 5-point 4-simplexes in one way, and the smaller 4-polytopes in the series cannot be partitioned into 4-simplexes at all. The 600-point (300 axis) 120-cell can be partitioned into 75 disjoint (4 axis) 4-orthoplexes. This partitioning can be done in 10 different ways, because two 4-orthoplexes can be positioned so that they share an axis without sharing all 8 vertices. The 120-cell contains 675 distinct 4-orthoplexes, each a distinct orthonormal basis with four orthogonal axes. Each axis occurs in 9 distinct 4-orthoplexes, and is orthogonal to its 27 distinct companion axes in those 4-orthoplexes, and to no other axes of the 120-cell.{{Sfn|Waegell & Aravind|2014}} Because the 4-simplex has no opposing vertices, its 5 vertices belong to 5 distinct orthonormal reference frames, such that two vertices of the same 4-simplex can never belong to the same 4-orthoplex. An atomic nucleus of atomic number <math>z</math> is a compound of <math>z</math> disjoint 4-simplexes, so it occupies exclusively <math>5 z</math> vertices of the 120-cell, in some configuration with the 5 vertices of each 4-simplex mutually equidistant from each other on the the 3-sphere. It is also a nuclide of neutron number <math>n</math>, so it is also a compound of <math>n</math> distinct 4-orthoplexes, not necessarily disjoint. The 4-simplex compound and 4-orthoplex compound may intersect, subject to the constraints above. The combined compounds form a single sparse configuration of the 120-cell. It is our conjecture that more stable nuclides correspond to sparse configurations with greater symmetry. .... == Dimensional relativity == The formulation of Euclidean relativity based on Coxeter's kinetic law of <math>n</math>-dimensional congruent transformations in Euclidean space may be called ''dimensional relativity'', since it captures the theories of special and general relativity, and has its roots in dimensional analogy. Dimensional analogy is the exploration of [[w:Hermann_Grassmann#Mathematician|Hermann Grassmann's vector space principle]], in which space cannot be limited to any finite number of dimensions. The geometry of higher-dimensional space is accessible by reason of direct analogy, as [[w:Ludwig Schläfli|Ludwig Schläfli]] subsequently demonstrated, and by algebraic methods after [[W:William Kingdon Clifford|Clifford]]. By analogy to the surface of the earth, the bounding surface of a spherical region of <math>n</math>-dimensional Euclidean space is an <math>(n-1)</math>-sphere, a spherical space of one fewer dimensions than the <math>n</math>-ball of Euclidean space it surrounds. In dimensional relativity the sky is not a ceiling, but an infinite regress of alternating Euclidean and spherical <math>n</math>-spaces of increasing <math>n</math>, accessible from each observer's point of view. By dimensional analogy, each observer looks up into their own reference frame's regress of concentric alternating <math>n</math>-spaces. By the capacity for dimensional analogy which they possess, some observers see deeper into <math>n</math>-dimensional space than others. == Polycentric spherical relativity == An intelligent observer equipped with the principle of dimensional relativity may perceive the universe from any reference frame, not only from their own proper inertial reference frame in the Euclidean <math>n</math>-space universe in which they physically locate themself. We see that every observer may also properly view themself as stationary and the universe as an <math>n</math>-sphere with themself at the center observing it, perceptually equidistant from all points on its <math>n</math>-space surface, including their own physical location which is one of those surface points, distinguished to them but moving on the surface, and not the center of anything. This ''polycentric model'' of the universe is a further restatement of the principle of relativity, and of the [[W:Copernican principle|Copernican principle]] that observation is democratic: observers occupy representative viewpoints, not privileged monocentric positions. The polycentric model is compatible with Galileo's relativity of uniformly moving objects in ordinary space, Einstein's special relativity of inertial reference frames in 4-dimensional spacetime, Einstein's general relativity of all reference frames in non-Euclidean spacetime, and Coxeter's dimensional relativity of orthogonal group actions in Euclidean spaces of any number of dimensions. The polycentric model should be known as Thoreau's principle of ''spherical relativity'', since the first precise written statement of it appears in 1849, contemporaneous with and independent of Schlafli's discovery of higher dimensional space: <blockquote>The universe is a sphere whose center is wherever there is intelligence.{{Sfn|Thoreau|1849|p=349|ps=; "The universe is a sphere whose center is wherever there is intelligence." [Contemporaneous and independent of [[W:Ludwig Schlafli|Ludwig Schlafli]]'s pioneering work enumerating the complete set of regular polyschemes in any number of dimensions.]}}</blockquote> == Revolutions == The original Copernican revolution in 1543 displaced the center of the universe from the center of the earth to a point farther away, the center of the sun, with the earth performing a ''revolution'' around the sun, and the stars remaining on a fixed 2-sphere around the sun instead of around the earth. But this led inevitably to the recognition that the sun must be a star itself, not equidistant from all the stars, and the center of but one of many spheres, no monotheistic center at all. In 1600 [[W:Giordano Bruno|Giordano Bruno]] who first openly advocated these views was burned at the stake in Rome's [[W:Campo de' Fiori|Campo de' Fiori]] by the Catholic inquisition. In such fashion the Euclidean four-dimensional revolution, emerging three to five centuries later, initially lends itself to the big bang theory of a single origin of the whole universe, but leads inevitably to the recognition that all the galaxies need not be equidistant from a single origin in time, any more than all the stars lie in the same galaxy, equidistant from a single center in space. The expanding sphere of matter on the surface of which we find ourselves living is likely to be one of many 3-spheres expanding at velocity <math>c</math>, with their big bang origins occurring at distinct times and places in the ''n''-dimensional universe. The most distant objects we see when we look up at night may not all have the same origin in space and time. As recently as Copernicus we believed all the stars lay on a single 2-sphere embedded in Euclidean 3-space, with our sun at its center. During the enlightenment observers beginning with Bruno dispersed those stars into an infinite Euclidean 3-space, and relinquished our privileged position at the center. Then Einstein showed that our 3-space could not be Euclidean, that it must be a 3-manifold curved in every place in obedience to Newton's inverse-square law of gravity; and in a geometry related to time, at least, it must be 4-dimensional. In the present work we propose a theory of ''n''-dimensional real space and how light travels in it, a theory which says we can see into four orthogonal dimensions of Euclidean space, and so when we look up at night we see cosmological objects distributed in at least four dimensions of space around us, rather than all located in our own local 3-space. Looking still deeper and farther out, our 4-space universe might be infinite, or at some vast radius (far greater than the radius of our big-bang 3-sphere) it might close into a 4-sphere. The universe viewed as a 4-sphere might, or might not, be expanding from some distant precursor to our big bang. The discovery of where exactly we are located in such a 4-sphere might bring about a whole new enlightenment. In any case the most distant objects we see when we look up at night may, or may not, lie in our 4-dimensional hyperplane. Real space has ''n'' dimensions as [[w:Hermann_Grassmann|Grassmann]] and [[w:Schläfli|Schläfli]] showed, and we do not know how many dimensions the most distant objects we see may be distributed in. They need not all lie within the four spatial dimensions in which we have now learned to observe them, any more than they all lie in our local 3-space. When we look up at the objects that surround us, we have no immediate way of discerning how many dimensions beyond three the space we are looking into has. We know their distance from us primarily by virtue of how long it takes their light to reach us. We can measure their distribution around us in 3-space or 4-space, but that is simply how we choose to measure their positions, not an actual finding of how they are distributed. Even if it is now evident that they do not all lie in the same 3-space, how many more dimensions than three are needed to contain them? We observe that our 4-ball galaxy is embedded in Euclidean <math>n</math>-space as one of many 4-ball galaxies, each translating in a distinct direction through 4-space at velocity <math>c</math>, on more or less divergent paths from each other. But only closer observation will reveal evidence of whether everything we see lies in the same Euclidean 4-space, or if it is distributed in five or more dimensions, and how it is moving there. To remain in agreement with the theory of relativity, the Euclidean four-dimensional viewpoint requires that all mass-carrying objects be in motion in some distinct direction through 4-space at the constant velocity <math>c</math>, although the relative velocity between nearby objects is much smaller since they move on similar vectors, aimed away from a common origin point in the past. It is natural to expect that objects moving at constant velocity away from a common origin will be distributed roughly on the surface of an expanding 3-sphere. Although their paths away from their origin are not straight lines but various helical isoclines (screw translation spirals), nearby objects must be translating radially at the same average velocity, since the objects in a system (such as our solar system or galaxy) do not separate rapidly over time but remain in orbital formation. Each system's screw translation has two [[w:Completely_orthogonal|completely orthogonal]] components of motion in 4-space, an orbital rotation (such as the earth's around our sun) and a linear translation of the entire system at velocity <math>c</math> in the direction of the original 3-sphere's radial expansion (along the system's proper time vector). Of course the view from our solar system does not suggest that the 3-sphere enclosing each galaxy is expanding at this great rate from its galactic center. The standard theory has been that the entire observable universe is expanding from a single big bang origin in time, with galaxies forming later. While the Euclidean four-dimensional viewpoint lends itself to that standard theory, it also supports theories which require no single origin point in space and time. These are the voyages of the starship Earth, to boldly go where no one has gone before. We made the jump to light speed long ago, in whatever big bang our atoms emerged from, and have never slowed down since. == Origins of the theory == Einstein himself may have been the first to imagine the universe as the three-dimensional surface of a four-dimensional Euclidean 3-sphere, in what was narrowly the first written articulation of a Euclidean 4-space universe, contemporaneous with the teen-aged Coxeter's (quoted below).{{Efn|[[W:William Rowan Hamilton|Hamilton]]'s algebra '''H''' of [[W:Quaternions|quaternions]] introduces (in 1843) the notion of a [[W:3-sphere|3-sphere]] embedded in a four-dimensional space, but Hamilton did not quite conceive of the quaternions as the Cartesian 4-coordinates of a Euclidean 4-space, and he did not describe our ordinary 3-space as embedded in Euclidean 4-space.}} Einstein did this as a [[W:Gedankenexperiment|gedankenexperiment]] in the context of investigating whether his equations of general relativity predicted an infinite or a finite universe, in his 1921 Princeton lecture. He invited us to imagine "A spherical manifold of three dimensions, embedded in a Euclidean continuum of four dimensions", but he was careful to disclaim parenthetically that "The aid of a fourth space dimension has naturally no significance except that of a mathematical artifice."<ref name=Einstein1923/> Informally, the Euclidean 4-dimensional theory of relativity may be given as a sort of reciprocal to that disclaimer of Einstein's: ''The Minkowski spacetime has naturally no significance except that of a mathematical artifice, as an aid to understanding how things will appear to an observer from their perspective; the foreshortenings, clock desynchronizations and other Lorentz transformations it predicts are proper calculations of actual perspective effects; but real space is a flat, Euclidean continuum of four orthogonal spatial dimensions, and in it the ordinary laws of a flat vector space hold (such as the Pythagorean theorem), and all sightline calculations work classically, so long as you consider all four spatial dimensions.'' The Euclidean theory of relativity differs from the special theory of relativity in ascribing to the physical universe a geometry of four or more orthogonal spatial dimensions, rather than the special theory's [[w:Minkowski spacetime|Minkowski spacetime]] geometry, in which three spatial dimensions and a time dimension comprise a unified non-Euclidean spacetime of four dimensions. Anco and Maghadam found that <math>SO(4)</math> breaks to <math>\mathbb{S}^3</math> (the 3-sphere) if the energy in a Kepler orbit is negative (an elliptical orbit), and to <math>H^3</math> (Minkowski spacetime) if the energy is positive (a hyperbolic orbit). Therefore the fact that the planets orbit on ellipses in our 3-space suggests that they orbit on a 3-sphere embedded in Euclidean 4-space. Thus we can conclude that <math>\mathbb{R}^4</math> is the actual geometry of our physical universe, and Minkowski spacetime is an abstraction of it; the reciprocal of Einstein's disclaimer is the more direct physical model. Of course spacetime remains a true and useful abstraction, although it must relinquish its privileged position as our exclusive conception of our place in space.{{Efn| ...origins of the Euclidean 4-space insight in the observations of Fock, Atkinson, Moser and others.}} The invention of Euclidean geometry of more than three spatial dimensions preceded Einstein's theories by more than fifty years, when it was worked out originally by the Swiss mathematician [[w:Ludwig Schläfli|Ludwig Schläfli]] before 1853.{{Sfn|Coxeter|1973|loc=§7. Ordinary Polytopes in Higher Space; §7.x. Historical remarks|pp=141-144|ps=; "Practically all the ideas in this chapter ... are due to Schläfli, who discovered them before 1853 — a time when Cayley, Grassmann and Möbius were the only other people who had ever conceived the possibility of geometry in more than three dimensions."}} Schläfli extended Euclid's geometry of one, two, and three dimensions in a direct way to four or more dimensions, generalizing the rules and terms of [[w:Euclidean geometry|Euclidean geometry]] to spaces of any number of dimensions. He coined the general term ''[[polyscheme]]'' to mean geometric forms of any number of dimensions, including two-dimensional [[w:polygon|polygons]], three-dimensional [[w:polyhedron|polyhedra]], four dimensional [[w:polychoron|polychora]], and so on, and in the process he found all of the [[w:Regular polytope|regular polyschemes]] that are possible in every dimension, including in particular the [[User:Dc.samizdat/Rotations#Sequence of regular 4-polytopes|six convex regular polychora]] which can be constructed in a Euclidean space of four dimensions (the set analogous to the five [[w:Platonic solid|Platonic solids]] the ancients found in three dimensional space). Thus Schläfli was the first to explore the fourth dimension, reveal its emergent geometric properties, and discover its astonishing regular objects. Because his work was only published posthumously in 1901, and remained almost completely unknown until Coxeter published [[w:Regular_Polytopes_(book)|Regular Polytopes]] in 1947, other researchers had more than fifty years to rediscover the regular polychora, and competing terms were coined; today [[w:Reinhold_Hoppe|Reinhold Hoppe]]'s word ''[[w:Polytope|polytope]]'' is the commonly used term for ''polyscheme.''{{Efn|[[w:Reinhold_Hoppe|Reinhold Hoppe]]'s German word ''polytop'' was introduced into English by [[W:Alicia Boole Stott|Alicia Boole Stott]], who like Hoppe and [[W:Thorold Gosset|Thorold Gosset]] rediscovered Schlafli's six regular convex 4-polytopes, with no knowledge of their prior discovery. Today Schläfli's original ''polyschem'', with its echo of ''schema'' as in the configurations of information structures, seems even more fitting in its generality than ''polytope'' -- perhaps analogously as information software (programming) is even more general than information hardware (computers).}} Because of this century-long lag in the dissemination of a scientific discovery, the regular 4-polytopes appear to have played no role at all, by any name, in the twentieth century discovery and evolution of the theories of relativity and quantum mechanics.{{Efn|One could argue that the higher-dimensional polytopes have barely influenced science or culture at all thus far. The physicist John Edward Huth's comprehensive deep dive through the history of cultural and scientific concepts of physical space, from ancient flatland models of the world through general relativity and quantum mechancs, shows exactly how we got to our present standard model of the universe, although it includes no mention of higher-dimensional Euclidean space.<ref>{{Cite book|last=Huth|first=John Edward|title=A Sense of Space: A local's guide to a flat earth, the edge of the cosmos, and other curious places|year=2025|publisher=University of Chicago Press}}</ref>}} == Boundaries == <blockquote>Ever since we discovered that Earth is round and turns like a mad-spinning top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.<ref>{{Cite book|author=Carlo Rovelli|author-link=W:Carlo Rovelli|title=Seven Brief Lessons on Physics|publisher=Riverhead|year=2016|isbn=978-0399184413}}</ref></blockquote> Of course it is strange to consciously contemplate this world we inhabit, our planet, our solar system, our 3-sphere surface in our vast galaxy, as the merest film, a boundary no thicker in the places we inhabit than the diameter of an electron (though much thicker in some places we cannot inhabit, such as the planet's core and the interior of stars). But is not our unconscious traditional concept of the boundary of our world even stranger? Since the enlightenment we are accustomed to thinking that there is nothing beyond three dimensional space: no boundary, because there is nothing else to separate us from. But anyone who knows the [[polyscheme]]s Schläfli discovered knows that space can have any number of dimensions, and that there are fundamental objects and motions to be discovered in four dimensions that are even more various and interesting than those we can discover in three. The strange thing, when we think about it that way, is that there ''is'' a boundary between three and four dimensional space. ''Why'' can't we move (or apparently, see) in more than three dimensions? Why is our physical world apparently only three dimensional? Why would it have just ''three'' dimensions, and not four, or five, or the ''n'' dimensions that Schläfli mapped? What is the nature of the boundary which confines us to just three dimensions? We know that in Euclidean geometry the boundary between three and four dimensions is itself a spherical three dimensional space, so we should suspect that we are materially confined within such a curved boundary surface. Light need not be confined with us within our three dimensional boundary space. We would look directly through four dimensional space in our natural way, by receiving light signals that travelled through it to us on straight lines. In that case the reason we do not observe a fourth spatial dimension in our vicinity is that there are no nearby objects in it, just off our hyperplane in the wild. The nearest 4-ball object we can see with our eyes is our sun, which lies equatorially in our own hyperplane, though it bulges out of it above and below. But when we look up at the heavens, every pinprick of light we observe is itself a four-dimensional object off our hyperplane, and they are distributed all around us in four-dimensional space through which we gaze. We are four-dimensionally sighted creatures, even though our bodies are three-dimensional objects, thin as an atom in the fourth dimension. But that should not perplex us: we can see into three dimensional space even though our retinas are two dimensional objects, thin as a photoreceptor cell. Our unconscious provincial concept is that there is nothing else outside our three dimensional world: no boundary, because there is nothing else to separate us from. But Schläfli discovered something else: all the astonishing regular objects that exist in higher dimensions, which vastly extend our notions of the beauty and mystery of space itself, and the intrinsic spatial symmetries of our universe which geometry reveals. Space is more commodious than we thought it was, and permits previously unimagined objects and motions. So our provincial conception of our place in it now has the same kind of status as our idea that the sun rises in the east and passes overhead: it is mere appearance, not a true model and no longer a proper explanation. An inertial boundary is a proper explanation, be it ever so thin. And would a boundary of ''no'' thickness, a mere abstraction with no physical power to separate, be a more suitable explanation? We must look for a physically powerful explanation in the geometry of space itself, which general relativity properly associates with the gravitational or inertial force. <blockquote>The number of dimensions possessed by a figure is the number of straight lines each perpendicular to all the others which can be drawn on it. Thus a point has no dimensions, a straight line one, a plane surface two, and a solid three .... In space as we now know it only three lines can be imagined perpendicular to each other. A fourth line, perpendicular to all the other three would be quite invisible and unimaginable to us. We ourselves and all the material things around us probably possess a fourth dimension, of which we are quite unaware. If not, from a four-dimensional point of view we are mere geometrical abstractions, like geometrical surfaces, lines, and points are to us. But this thickness in the fourth dimension must be exceedingly minute, if it exists at all. That is, we could only draw an exceedingly small line perpendicular to our three perpendicular lines, length, breadth and thickness, so small that no microscope could ever perceive it. We can find out something about the conditions of the fourth and higher dimensions if they exist, without being certain that they do exist, by a process which I have termed "Dimensional Analogy."<ref>{{Citation|title=Dimensional Analogy|last=Coxeter|first=Donald|date=February 1923|publisher=Coxeter Fonds, University of Toronto Archives|authorlink=W:Harold Scott MacDonald Coxeter|series=|postscript=|work=}}</ref></blockquote> I believe, but I cannot prove, that we live in real space, which is Schläfli's Euclidean space of ''n'' analogous dimensions. As Grassmann showed first, space cannot be limited to any finite number of dimensions. There will always be higher dimensions to discover, first in imagination and then to explore physically, each an astonishing new enlightenment.<ref>{{Cite book|first=T.S.|last=Eliot|title=Little Gidding|volume=Four Quartets|year=1943}}<blockquote> :We shall not cease from exploration :And the end of all our exploring :Will be to arrive where we started :And know the place for the first time. :Through the unknown, remembered gate :When the last of earth left to discover :Is that which was the beginning; :At the source of the longest river :The voice of the hidden waterfall :And the children in the apple-tree :Not known, because not looked for :But heard, half-heard, in the stillness :Between two waves of the sea. </blockquote></ref> Schläfli discovered every regular convex polytope that exists in any dimension, but that was only the beginning of the story of dimensional analogy, not its end or even the end of its beginning. That project is forever beginning anew. Coxeter discovered that Schläfli's Euclidean space is an expression of intrinsic symmetries, as Noether discovered all of physics is. Kappraff and Adamson discovered that even the sequences of humble regular polygons have fractal complexity, so symmetry itself is chaotic, always reachable but forever beyond our complete grasp. We are on a wilderness project, and just at its beginning, but already we observe a Euclidean space of four or more orthogonal spatial dimensions in which all objects with mass move ceaselessly at the constant velocity <math>c</math>, the universal rate at which everything moves, quantum events occur, and each of our proper times evolves. I believe these facts explain the experimentally verified theories of relativity and quantum mechanics, by revealing their unified polycentric geometry, the same way the facts about Copernicus's heliocentric solar system explained the observed motions of the planets, by revealing the geometry of gravity to Kepler. But others will have to do the math, work out the physics, and perform experiments to prove or disprove all of this, because I don't have the mathematics; entirely unlike Coxeter and Einstein, I am illiterate in those languages. <blockquote> ::::::BEECH :Where my imaginary line :Bends square in woods, an iron spine :And pile of real rocks have been founded. :And off this corner in the wild, :Where these are driven in and piled, :One tree, by being deeply wounded, :Has been impressed as Witness Tree :And made commit to memory :My proof of being not unbounded. :Thus truth's established and borne out, :Though circumstanced with dark and doubt— :Though by a world of doubt surrounded. :::::::—''The Moodie Forester''<ref>{{Cite book|title=A Witness Tree|last=Frost|first=Robert|year=1942|series=The Poetry of Robert Frost|publisher=Holt, Rinehart and Winston|edition=1969|}}</ref> </blockquote> == Appendix: Sequence of regular 4-polytopes == {{Regular convex 4-polytopes|wiki=W:|columns=7}} == ... == {{Efn|In a ''[[W:William Kingdon Clifford|Clifford]] displacement'', also known as an [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinic rotation]], all the Clifford parallel{{Efn|name=Clifford parallels}} invariant planes are displaced in four orthogonal directions (two completely orthogonal planes) at once: they are rotated by the same angle, and at the same time they are tilted ''sideways'' by that same angle. A [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|Clifford displacement]] is [[W:8-cell#Radial equilateral symmetry|4-dimensionally diagonal]].{{Efn|name=isoclinic 4-dimensional diagonal}} Every plane that is Clifford parallel to one of the completely orthogonal planes (including in this case an entire Clifford parallel bundle of 4 hexagons, but not all 16 hexagons) is invariant under the isoclinic rotation: all the points in the plane rotate in circles but remain in the plane, even as the whole plane tilts sideways. All 16 hexagons rotate by the same angle (though only 4 of them do so invariantly). All 16 hexagons are rotated by 60 degrees, and also displaced sideways by 60 degrees to a Clifford parallel hexagon. All of the other central polygons (e.g. squares) are also displaced to a Clifford parallel polygon 60 degrees away.|name=Clifford displacement}} {{Efn|It is not difficult to visualize four hexagonal planes intersecting at 60 degrees to each other, even in three dimensions. Four hexagonal central planes intersect at 60 degrees in the [[W:cuboctahedron|cuboctahedron]]. Four of the 24-cell's 16 hexagonal central planes (lying in the same 3-dimensional hyperplane) intersect at each of the 24-cell's vertices exactly the way they do at the center of a cuboctahedron. But the ''edges'' around the vertex do not meet as the radii do at the center of a cuboctahedron; the 24-cell has 8 edges around each vertex, not 12, so its vertex figure is the cube, not the cuboctahedron. The 8 edges meet exactly the way 8 edges do at the apex of a canonical [[W:cubic pyramid]|cubic pyramid]].{{Efn|name=24-cell vertex figure}}|name=cuboctahedral hexagons}} {{Efn|name=radially equilateral}} {{Efn|Eight {{sqrt|1}} edges converge in curved 3-dimensional space from the corners of the 24-cell's cubical vertex figure{{Efn|The [[W:vertex figure|vertex figure]] is the facet which is made by truncating a vertex; canonically, at the mid-edges incident to the vertex. But one can make similar vertex figures of different radii by truncating at any point along those edges, up to and including truncating at the adjacent vertices to make a ''full size'' vertex figure. Stillwell defines the vertex figure as "the convex hull of the neighbouring vertices of a given vertex".{{Sfn|Stillwell|2001|p=17}} That is what serves the illustrative purpose here.|name=full size vertex figure}} and meet at its center (the vertex), where they form 4 straight lines which cross there. The 8 vertices of the cube are the eight nearest other vertices of the 24-cell. The straight lines are geodesics: two {{sqrt|1}}-length segments of an apparently straight line (in the 3-space of the 24-cell's curved surface) that is bent in the 4th dimension into a great circle hexagon (in 4-space). Imagined from inside this curved 3-space, the bends in the hexagons are invisible. From outside (if we could view the 24-cell in 4-space), the straight lines would be seen to bend in the 4th dimension at the cube centers, because the center is displaced outward in the 4th dimension, out of the hyperplane defined by the cube's vertices. Thus the vertex cube is actually a [[W:cubic pyramid|cubic pyramid]]. Unlike a cube, it seems to be radially equilateral (like the tesseract and the 24-cell itself): its "radius" equals its edge length.{{Efn|The vertex cubic pyramid is not actually radially equilateral,{{Efn|name=radially equilateral}} because the edges radiating from its apex are not actually its radii: the apex of the [[W:cubic pyramid|cubic pyramid]] is not actually its center, just one of its vertices.}}|name=24-cell vertex figure}} {{Efn|The hexagons are inclined (tilted) at 60 degrees with respect to the unit radius coordinate system's orthogonal planes. Each hexagonal plane contains only ''one'' of the 4 coordinate system axes.{{Efn|Each great hexagon of the 24-cell contains one axis (one pair of antipodal vertices) belonging to each of the three inscribed 16-cells. The 24-cell contains three disjoint inscribed 16-cells, rotated 60° isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other (so their corresponding vertices are 120° {{=}} {{radic|3}} apart). A [[16-cell#Coordinates|16-cell is an orthonormal ''basis'']] for a 4-dimensional coordinate system, because its 8 vertices define the four orthogonal axes. In any choice of a vertex-up coordinate system (such as the unit radius coordinates used in this article), one of the three inscribed 16-cells is the basis for the coordinate system, and each hexagon has only ''one'' axis which is a coordinate system axis.|name=three basis 16-cells}} The hexagon consists of 3 pairs of opposite vertices (three 24-cell diameters): one opposite pair of ''integer'' coordinate vertices (one of the four coordinate axes), and two opposite pairs of ''half-integer'' coordinate vertices (not coordinate axes). For example: {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,{{spaces|2}}1,{{spaces|2}}0) {{indent|5}}({{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}({{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|5}}(–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}},–{{sfrac|1|2}}){{spaces|3}}(–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}},–{{sfrac|1|2}},{{spaces|2}}{{sfrac|1|2}}) {{indent|17}}({{spaces|2}}0,{{spaces|2}}0,–1,{{spaces|2}}0)<br> is a hexagon on the ''y'' axis. Unlike the {{sqrt|2}} squares, the hexagons are actually made of 24-cell edges, so they are visible features of the 24-cell.|name=non-orthogonal hexagons|group=}} {{Efn|Visualize the three [[16-cell]]s inscribed in the 24-cell (left, right, and middle), and the rotation which takes them to each other. [[24-cell#Reciprocal constructions from 8-cell and 16-cell|The vertices of the middle 16-cell lie on the (w, x, y, z) coordinate axes]];{{Efn|name=six orthogonal planes of the Cartesian basis}} the other two are rotated 60° [[W:Rotations in 4-dimensional Euclidean space#Isoclinic rotations|isoclinically]] to its left and its right. The 24-vertex 24-cell is a compound of three 16-cells, whose three sets of 8 vertices are distributed around the 24-cell symmetrically; each vertex is surrounded by 8 others (in the 3-dimensional space of the 4-dimensional 24-cell's surface), the way the vertices of a cube surround its center.{{Efn|name=24-cell vertex figure}} The 8 surrounding vertices (the cube corners) lie in other 16-cells: 4 in the other 16-cell to the left, and 4 in the other 16-cell to the right. They are the vertices of two tetrahedra inscribed in the cube, one belonging (as a cell) to each 16-cell. If the 16-cell edges are {{radic|2}}, each vertex of the compound of three 16-cells is {{radic|1}} away from its 8 surrounding vertices in other 16-cells. Now visualize those {{radic|1}} distances as the edges of the 24-cell (while continuing to visualize the disjoint 16-cells). The {{radic|1}} edges form great hexagons of 6 vertices which run around the 24-cell in a central plane. ''Four'' hexagons cross at each vertex (and its antipodal vertex), inclined at 60° to each other.{{Efn|name=cuboctahedral hexagons}} The [[24-cell#Hexagons|hexagons]] are not perpendicular to each other, or to the 16-cells' perpendicular [[24-cell#Squares|square central planes]].{{Efn|name=non-orthogonal hexagons}} The left and right 16-cells form a tesseract.{{Efn|Each pair of the three 16-cells inscribed in the 24-cell forms a 4-dimensional [[W:tesseract|hypercube (a tesseract or 8-cell)]], in [[24-cell#Relationships among interior polytopes|dimensional analogy]] to the way two tetrahedra form a cube: the two 8-vertex 16-cells are inscribed in the 16-vertex tesseract, occupying its alternate vertices. The third 16-cell does not lie within the tesseract; its 8 vertices protrude from the sides of the tesseract, forming a cubic pyramid on each of the tesseract's cubic cells. The three pairs of 16-cells form three tesseracts.{{Efn|name=three 8-cells}} The tesseracts share vertices, but the 16-cells are completely disjoint.{{Efn|name=completely disjoint}}|name=three 16-cells form three tesseracts}} Two 16-cells have vertex-pairs which are one {{radic|1}} edge (one hexagon edge) apart. But a [[24-cell#Simple rotations|''simple'' rotation]] of 60° will not take one whole 16-cell to another 16-cell, because their vertices are 60° apart in different directions, and a simple rotation has only one hexagonal plane of rotation. One 16-cell ''can'' be taken to another 16-cell by a 60° [[24-cell#Isoclinic rotations|''isoclinic'' rotation]], because an isoclinic rotation is [[3-sphere]] symmetric: four [[24-cell#Clifford parallel polytopes|Clifford parallel hexagonal planes]] rotate together, but in four different rotational directions,{{Efn|name=Clifford displacement}} taking each 16-cell to another 16-cell. But since an isoclinic 60° rotation is a ''diagonal'' rotation by 60° in ''two'' completely orthogonal directions at once,{{Efn|name=isoclinic geodesic}} the corresponding vertices of the 16-cell and the 16-cell it is taken to are 120° apart: ''two'' {{radic|1}} hexagon edges (or one {{radic|3}} hexagon chord) apart, not one {{radic|1}} edge (60°) apart as in a simple rotation.{{Efn|name=isoclinic 4-dimensional diagonal}} By the [[W:chiral|chiral]] diagonal nature of isoclinic rotations, the 16-cell ''cannot'' reach the adjacent 16-cell by rotating toward it; it can only reach the 16-cell ''beyond'' it. But of course, the 16-cell beyond the 16-cell to its right is the 16-cell to its left. So a 60° isoclinic rotation ''will'' take every 16-cell to another 16-cell: a 60° ''right'' isoclinic rotation will take the middle 16-cell to the 16-cell we may have originally visualized as the ''left'' 16-cell, and a 60° ''left'' isoclinic rotation will take the middle 16-cell to the 16-cell we visualized as the ''right'' 16-cell. (If so, that was our error in visualization; the 16-cell to the "left" is in fact the one reached by the left isoclinic rotation, as that is the only sense in which the two 16-cells are left or right of each other.)|name=three isoclinic 16-cells}} {{Efn|In a double rotation each vertex can be said to move along two completely orthogonal great circles at the same time, but it does not stay within the central plane of either of those original great circles; rather, it moves along a helical geodesic that traverses diagonally between great circles. The two completely orthogonal planes of rotation are said to be ''invariant'' because the points in each stay in the plane ''as the plane moves'', tilting sideways by the same angle that the other plane rotates.|name=helical geodesic}} {{Efn|A point under isoclinic rotation traverses the diagonal{{Efn|name=isoclinic 4-dimensional diagonal}} straight line of a single '''isoclinic geodesic''', reaching its destination directly, instead of the bent line of two successive '''simple geodesics'''. A '''[[W:geodesic|geodesic]]''' is the ''shortest path'' through a space (intuitively, a string pulled taught between two points). Simple geodesics are great circles lying in a central plane (the only kind of geodesics that occur in 3-space on the 2-sphere). Isoclinic geodesics are different: they do ''not'' lie in a single plane; they are 4-dimensional [[W:helix|spirals]] rather than simple 2-dimensional circles.{{Efn|name=helical geodesic}} But they are not like 3-dimensional [[W:screw threads|screw threads]] either, because they form a closed loop like any circle (after ''two'' revolutions). Isoclinic geodesics are ''4-dimensional great circles'', and they are just as circular as 2-dimensional circles: in fact, twice as circular, because they curve in a circle in two completely orthogonal directions at once.{{Efn|Isoclinic geodesics are ''4-dimensional great circles'' in the sense that they are 1-dimensional geodesic ''lines'' that curve in 4-space in two completely orthogonal planes at once. They should not be confused with ''great 2-spheres'',{{Sfn|Stillwell|2001|p=24}} which are the 4-dimensional analogues of 2-dimensional great circles (great 1-spheres).}} These '''isoclines''' are geodesic 1-dimensional lines embedded in a 4-dimensional space. On the 3-sphere{{Efn|All isoclines are geodesics, and isoclines on the 3-sphere are circles (curving equally in each dimension), but not all isoclines on 3-manifolds in 4-space are circles.}} they always occur in [[W:chiral|chiral]] pairs and form a pair of [[W:Villarceau circle|Villarceau circle]]s on the [[W:Clifford torus|Clifford torus]],{{Efn|Isoclines on the 3-sphere occur in non-intersecting chiral pairs. A left and a right isocline form a [[W:Hopf link|Hopf link]] called the {1,1} torus knot{{Sfn|Dorst|2019|loc=§1. Villarceau Circles|p=44|ps=; "In mathematics, the path that the (1, 1) knot on the torus traces is also known as a [[W:Villarceau circle|Villarceau circle]]. Villarceau circles are usually introduced as two intersecting circles that are the cross-section of a torus by a well-chosen plane cutting it. Picking one such circle and rotating it around the torus axis, the resulting family of circles can be used to rule the torus. By nesting tori smartly, the collection of all such circles then form a [[W:Hopf fibration|Hopf fibration]].... we prefer to consider the Villarceau circle as the (1, 1) torus knot [a [[W:Hopf link|Hopf link]]] rather than as a planar cut [two intersecting circles]."}} in which ''each'' of the two linked circles traverses all four dimensions.}} the paths of the left and the right [[W:Rotations in 4-dimensional Euclidean space#Double rotations|isoclinic rotation]]. They are [[W:Helix|helices]] bent into a [[W:Möbius strip|Möbius loop]] in the fourth dimension, taking a diagonal [[W:Winding number|winding route]] twice around the 3-sphere through the non-adjacent vertices of a 4-polytope's [[W:Skew polygon#Regular skew polygons in four dimensions|skew polygon]].|name=isoclinic geodesic}} {{Efn|[[File:Hopf band wikipedia.png|thumb|150px|Two [[W:Clifford parallel|Clifford parallel]] great circles spanned by a twisted [[W:Annulus (mathematics)|annulus]].]][[W:Clifford parallel|Clifford parallel]]s are non-intersecting curved lines that are parallel in the sense that the perpendicular (shortest) distance between them is the same at each point. A double helix is an example of Clifford parallelism in ordinary 3-dimensional Euclidean space. In 4-space Clifford parallels occur as geodesic great circles on the [[W:3-sphere|3-sphere]].{{Sfn|Kim|Rote|2016|pp=8-10|loc=Relations to Clifford Parallelism}} Whereas in 3-dimensional space, any two geodesic great circles on the [[W:2-sphere|2-sphere]] will always intersect at two antipodal points, in 4-dimensional space not all great circles intersect. In 4-polytopes various discrete sets of Clifford parallel non-intersecting geodesic great circles can be found on the 3-sphere. They spiral around each other in [[W:Hopf fibration|Hopf fiber bundles]] which visit all the vertices just once. The simplest example is that six mutually orthogonal great circles can be drawn on the 3-sphere, as three pairs of completely orthogonal great circles, intersecting at 8 points defining a [[16-cell]]. Each completely orthogonal pair of circles is Clifford parallel. They cannot intersect at all, because they lie in planes which intersect at only one point: the center of the 16-cell. Because they are perpendicular and share a common center, the two circles are obviously not parallel and separate in the usual way of parallel circles in 3 dimensions; rather they are connected like adjacent links in a chain, each passing through the other without intersecting at any points, forming a [[W:Hopf link|Hopf link]]|name=Clifford parallels}} {{Efn|In the 24-cell each great square plane is completely orthogonal{{Efn|name=completely orthogonal planes}} to another great square plane, and each great hexagon plane is completely orthogonal to a plane which intersects only two vertices: a great [[W:digon|digon]] plane.|name=pairs of completely orthogonal planes}} {{Efn|In an [[24-cell#Isoclinic rotations|isoclinic rotation]], each point anywhere in the 4-polytope moves an equal distance in four orthogonal directions at once, on a [[W:8-cell#Radial equilateral symmetry|4-dimensional diagonal]]. The point is displaced a total [[W:Pythagorean distance]] equal to the square root of four times the square of that distance. For example, when the unit-radius 24-cell rotates isoclinically 60° in a hexagon invariant plane and 60° in its completely orthogonal invariant plane,{{Efn|name=pairs of completely orthogonal planes}} all vertices are displaced to a vertex two edge lengths away. Each vertex is displaced to another vertex {{radic|3}} (120°) away, moving {{radic|3/4}} in four orthogonal coordinate directions.|name=isoclinic 4-dimensional diagonal}} {{Efn|Each square plane is isoclinic (Clifford parallel) to five other square planes but completely orthogonal{{Efn|name=completely orthogonal planes}} to only one of them.{{Efn|name=Clifford parallel squares in the 16-cell and 24-cell}} Every pair of completely orthogonal planes has Clifford parallel great circles, but not all Clifford parallel great circles are orthogonal (e.g., none of the hexagonal geodesics in the 24-cell are mutually orthogonal).|name=only some Clifford parallels are orthogonal}} {{Efn|In the [[16-cell#Rotations|16-cell]] the 6 orthogonal great squares form 3 pairs of completely orthogonal great circles; each pair is Clifford parallel. In the 24-cell, the 3 inscribed 16-cells lie rotated 60 degrees isoclinically{{Efn|name=isoclinic 4-dimensional diagonal}} with respect to each other; consequently their corresponding vertices are 120 degrees apart on a hexagonal great circle. Pairing their vertices which are 90 degrees apart reveals corresponding square great circles which are Clifford parallel. Each of the 18 square great circles is Clifford parallel not only to one other square great circle in the same 16-cell (the completely orthogonal one), but also to two square great circles (which are completely orthogonal to each other) in each of the other two 16-cells. (Completely orthogonal great circles are Clifford parallel, but not all Clifford parallels are orthogonal.{{Efn|name=only some Clifford parallels are orthogonal}}) A 60 degree isoclinic rotation of the 24-cell in hexagonal invariant planes takes each square great circle to a Clifford parallel (but non-orthogonal) square great circle in a different 16-cell.|name=Clifford parallel squares in the 16-cell and 24-cell}} {{Efn|In 4 dimensional space we can construct 4 perpendicular axes and 6 perpendicular planes through a point. Without loss of generality, we may take these to be the axes and orthogonal central planes of a (w, x, y, z) Cartesian coordinate system. In 4 dimensions we have the same 3 orthogonal planes (xy, xz, yz) that we have in 3 dimensions, and also 3 others (wx, wy, wz). Each of the 6 orthogonal planes shares an axis with 4 of the others, and is ''completely orthogonal'' to just one of the others: the only one with which it does not share an axis. Thus there are 3 pairs of completely orthogonal planes: xy and wz intersect only at the origin; xz and wy intersect only at the origin; yz and wx intersect only at the origin.|name=six orthogonal planes of the Cartesian basis}} {{Efn|Two planes in 4-dimensional space can have four possible reciprocal positions: (1) they can coincide (be exactly the same plane); (2) they can be parallel (the only way they can fail to intersect at all); (3) they can intersect in a single line, as two non-parallel planes do in 3-dimensional space; or (4) '''they can intersect in a single point'''{{Efn|To visualize how two planes can intersect in a single point in a four dimensional space, consider the Euclidean space (w, x, y, z) and imagine that the w dimension represents time rather than a spatial dimension. The xy central plane (where w{{=}}0, z{{=}}0) shares no axis with the wz central plane (where x{{=}}0, y{{=}}0). The xy plane exists at only a single instant in time (w{{=}}0); the wz plane (and in particular the w axis) exists all the time. Thus their only moment and place of intersection is at the origin point (0,0,0,0).|name=how planes intersect at a single point}} (and they ''must'', if they are completely orthogonal).{{Efn|Two flat planes A and B of a Euclidean space of four dimensions are called ''completely orthogonal'' if and only if every line in A is orthogonal to every line in B. In that case the planes A and B intersect at a single point O, so that if a line in A intersects with a line in B, they intersect at O.{{Efn|name=six orthogonal planes of the Cartesian basis}}|name=completely orthogonal planes}}|name=how planes intersect}} {{Efn|Polytopes are '''completely disjoint''' if all their ''element sets'' are disjoint: they do not share any vertices, edges, faces or cells. They may still overlap in space, sharing 4-content, volume, area, or lineage.|name=completely disjoint}} {{Efn|If the [[W:Euclidean distance|Pythagorean distance]] between any two vertices is {{sqrt|1}}, their geodesic distance is 1; they may be two adjacent vertices (in the curved 3-space of the surface), or a vertex and the center (in 4-space). If their Pythagorean distance is {{sqrt|2}}, their geodesic distance is 2 (whether via 3-space or 4-space, because the path along the edges is the same straight line with one 90^o bend in it as the path through the center). If their Pythagorean distance is {{sqrt|3}}, their geodesic distance is still 2 (whether on a hexagonal great circle past one 60^o bend, or as a straight line with one 60^o bend in it through the center). Finally, if their Pythagorean distance is {{sqrt|4}}, their geodesic distance is still 2 in 4-space (straight through the center), but it reaches 3 in 3-space (by going halfway around a hexagonal great circle).|name=Geodesic distance}} {{Efn|Two angles are required to fix the relative positions of two planes in 4-space.{{Sfn|Kim|Rote|2016|p=7|loc=§6 Angles between two Planes in 4-Space|ps=; "In four (and higher) dimensions, we need two angles to fix the relative position between two planes. (More generally, ''k'' angles are defined between ''k''-dimensional subspaces.)"}} Since all planes in the same [[W:hyperplane|hyperplane]] are 0 degrees apart in one of the two angles, only one angle is required in 3-space. Great hexagons in different hyperplanes are 60 degrees apart in ''both'' angles. Great squares in different hyperplanes are 90 degrees apart in ''both'' angles (completely orthogonal){{Efn|name=completely orthogonal planes}} or 60 degrees apart in ''both'' angles.{{Efn||name=Clifford parallel squares in the 16-cell and 24-cell}} Planes which are separated by two equal angles are called ''isoclinic''. Planes which are isoclinic have [[W:Clifford parallel|Clifford parallel]] great circles.{{Efn|name=Clifford parallels}} A great square and a great hexagon in different hyperplanes are neither isoclinic nor Clifford parallel; they are separated by a 90 degree angle ''and'' a 60 degree angle.|name=two angles between central planes}} {{Efn|The 24-cell contains 3 distinct 8-cells (tesseracts), rotated 60° isoclinically with respect to each other. The corresponding vertices of two 8-cells are {{radic|3}} (120°) apart. Each 8-cell contains 8 cubical cells, and each cube contains four {{radic|3}} chords (its long diagonals). The 8-cells are not completely disjoint{{Efn|name=completely disjoint}} (they share vertices), but each cube and each {{radic|3}} chord belongs to just one 8-cell. The {{radic|3}} chords joining the corresponding vertices of two 8-cells belong to the third 8-cell.|name=three 8-cells}} {{Efn|Departing from any vertex V₀ in the original great hexagon plane of isoclinic rotation P₀, the first vertex reached V₁ is 120 degrees away along a {{radic|3}} chord lying in a different hexagonal plane P₁. P₁ is inclined to P₀ at a 60° angle.{{Efn|P₀ and P₁ lie in the same hyperplane (the same central cuboctahedron) so their other angle of separation is 0.{{Efn|name=two angles between central planes}}}} The second vertex reached V₂ is 120 degrees beyond V₁ along a second {{radic|3}} chord lying in another hexagonal plane P₂ that is Clifford parallel to P₀.{{Efn|P₀ and P₂ are 60° apart in ''both'' angles of separation.{{Efn|name=two angles between central planes}} Clifford parallel planes are isoclinic (which means they are separated by two equal angles), and their corresponding vertices are all the same distance apart. Although V₀ and V₂ are ''two'' {{radic|3}} chords apart{{Efn|V₀ and V₂ are two {{radic|3}} chords apart on the geodesic path of this rotational isocline, but that is not the shortest geodesic path between them. In the 24-cell, it is impossible for two vertices to be more distant than ''one'' {{radic|3}} chord, unless they are antipodal vertices {{radic|4}} apart.{{Efn|name=Geodesic distance}} V₀ and V₂ are ''one'' {{radic|3}} chord apart on some other isocline. More generally, isoclines are geodesics because the distance between their ''adjacent'' vertices is the shortest distance between those two vertices, but a path between two vertices along a geodesic is not always the shortest distance between them (even on ordinary great circle geodesics).}}, P₀ and P₂ are just one {{radic|1}} edge apart (at every pair of ''nearest'' vertices).}} (Notice that V₁ lies in both intersecting planes P₁ and P₂, as V₀ lies in both P₀ and P₁. But P₀ and P₂ have ''no'' vertices in common; they do not intersect.) The third vertex reached V₃ is 120 degrees beyond V₂ along a third {{radic|3}} chord lying in another hexagonal plane P₃ that is Clifford parallel to P₁. The three {{radic|3}} chords lie in different 8-cells.{{Efn|name=three 8-cells}} V₀ to V₃ is a 360° isoclinic rotation.|name=360 degree geodesic path visiting 3 hexagonal planes}} {{Sfn|Mamone, Pileio & Levitt|2010|loc=§4.5 Regular Convex 4-Polytopes|pp=1438-1439|ps=; the 24-cell has 1152 symmetry operations (rotations and reflections) as enumerated in Table 2, symmetry group 𝐹₄.}} ==Notes== {{Regular convex 4-polytopes Notelist|wiki=W:}} ==Citations== {{Regular convex 4-polytopes Reflist|wiki=W:}} ==References== {{Refbegin}} * {{Cite book|title=A Week on the Concord and Merrimack Rivers|last=Thoreau|first=Henry David|author-link=W:Thoreau|publisher=James Munroe and Company|year=1849|isbn=|location=Boston|ref={{SfnRef|Thoreau|1849}}}} * {{Cite journal|title=Theoretical Evidence for Principles of Special Relativity Based on Isotropic and Uniform Four-Dimensional Space|first=Takuya|last=Yamashita|date=25 May 2023|doi= 10.20944/preprints202305.1785.v1|journal=Preprints|volume=2023|issue=2023051785|url=https://doi.org/10.20944/preprints202305.1785.v1|ref={{SfnRef|Yamashita|2023}}}} * {{Cite_arXiv | arxiv=2512.02903v2 | date=2 January 2026 | title=Symmetry transformation group arising from the Laplace–Runge–Lenz vector | first1=Stephen C. | last1=Anco | first2=Mahdieh Gol Bashmani | last2=Moghadam | class=math-ph}} === [[Polyscheme|Polyschemes]] === {{Regular convex 4-polytopes Refs|wiki=W:}} {{Refend}} b5pa9jh4td9wtpkr1jdknh7hnygor09 0 306601 2844956 2676945 2026-11-09T09:49:27Z ~2026-59426-44 3114060 /* Overview */ 2844956 wikitext text/x-wiki {{title|Adverse childhood experiences and emotion regulation:<br>What is the relationship between ACEs and emotion regulation?}} {{MECR3|1=https://youtu.be/O1l3AqS5Pg4}} __TOC__ ==Overview== {{RoundBoxTop|theme=3}} [[File:گریه کردن دختر بچه Cry baby girl 01.jpg|thumb|''Figure 1.'' Adverse Childhood Experiences can impact a child's emotional development and their ability to manage their emotions effectively as an adult.]] ;Case study Mason grew up in a home where the mood was unpredictable. He can recall several instances where he was exposed to physical violence between his parents. There were long periods of time where Mason was left to fend for himself as, without warning, his parents could become distant or angry, which made Mason tip-toe around them, afraid to approach them not knowing if he would catch them on a good or a bad day. As Mason got older, he became withdrawn from his peers, afraid to disappoint those around him, and found it challenging to cope with frequent and overwhelming feelings of anger, sadness, and feeling on edge. How do you think Mason's upbringing influenced his emotional development? Do you think Mason is struggling to regulate his emotions as a result of his experiences? How might these early experiences shape his ability to form trusting relationships in the future? {{RoundBoxBottom}} This case study is not a unique scenario. Many children experience adverse events such as abuse, neglect and exposure to domestic violence, which may have lasting impacts on their emotional development. According to 2024 [https://www.unicef.org/press-releases/nearly-400-million-young-children-worldwide-regularly-experience-violent-discipline UNICEF] estimates, nearly 400 million children under the age of 5 or 6 in 10 children within that age group globally, endure psychological aggression or physical abuse at home on a regular basis. Adverse Childhood experiences are also linked to a range of negative outcomes in adulthood, including mental health disorders, substance abuse, and relationship challenges. Understanding the impact of ACEs on emotion/emotional regulation is important as it aids in preventing long-term psychological issues that can stem from significant adversity in childhood, and it can aid in developing effective interventions. Through vast and abundant research spanning over half a century, there have been valuable insights into how ACEs influence [[w:https://en.wikipedia.org/wiki/Emotional_self-regulation|emotional regulation]] {{ic|}}, and how interventions can mitigate the effects of childhood adversity. This chapter explores the relationship between ACEs and emotional regulation, addressing the following focus questions. {{RoundBoxTop|theme=7}} {{ic|}} 1. How are ACEs and Emotion Regulation defined? 2. What is the relationship between ACEs and Emotion Regulation? 3. How do theoretical perspectives explain the role of ACEs on emotion regulation? 4. How can interventions help mitigate the effects of ACEs on emotional regulation? {{RoundBoxBottom}} <quiz display="simple"> {Which of the following could be considered an adverse childhood experience (ACE)? |type="()"} - Emotional and physical neglect - Physical, sexual, emotional and psychological abuse - Bullying - Divorce between parents - Deaths in the family + All of the above </quiz> == Defining and clarifying the relationships between the constructs == === What is an adverse childhood experience? === According to Harvard's [https://developingchild.harvard.edu/resources/aces-and-toxic-stress-frequently-asked-questions/ Center of the Developing Child], the term ACEs serves as an acronym for Adverse Childhood Experiences, originating from a study conducted in 1995 by the Centres for Disease Control and the Kaiser Permanent Health care organisation in California. Kaiser (1998) suggested the presence of three forms of childhood adversity, including physical and emotional abuse, neglect, and household dysfunction, but can extend to experiences beyond the household, such as adverse social or school experiences such as bullying. === What is emotion/emotional regulation? === The [https://dictionary.apa.org/emotion-regulation American Psychological Association] defines emotional regulation as the ability to modulate an emotion or set of emotions, using explicit mechanisms such as learning to construe situations differently in order to manage them better, and to change the target of an emotion to produce a more positive outcome, while recognising how different responses can be used in the service of a given emotional state. Implicit mechanisms occur without deliberate monitoring, which involve modulating the intensity or duration of an emotional response without the need for awareness. Emotional regulation typically increases across the lifespan (American Psychological Association, 2018). === What is the relationship between ACEs and Emotion Regulation? === There is an wealth of research providing empirical support to suggest that ACEs to have a directional impact on emotion regulation. For instance, according to Snyder, et al (2024) and Ye et al (2024), difficulties with emotion regulation are well-documented reactions to early ACEs, as a multitude of studies have reported ACEs to have detrimental effects on emotion regulation. Studies including Chefetz (2015), Hughes et al (2017) and Poole et al (2018), have indicated a greater occurence of ACEs as being associated with difficulties in the regulation of emotion, as well as structural alterations in personality, interpersonal difficulties in adulthood, insecure attachment styles, and mental illness. These contributions, along with many others have emphasised the developmental importance of childhood experience on later functioning, substantiating the need to further explore the roles of ACEs on psychological functioning. However, establishing causality is challenging, as without the consideration of other factors, such as temperament, genetics, study design and other environmental influences and contextual factors, the impact of ACEs alone is difficult to observe. == Theoretical approaches to understanding the relationship between ACEs and emotional regulation == Theoretical frameworks, particularly those established over time, can provide valuable insights into how ACEs contribute to emotional challenges. Well renowned theories such as the Attachment Theory, The Social Learning Theory, the Family Systems Theory and the Polyvagal Theory in particular, offer critical perspectives into how ACEs can impair or disrupt emotional regulation. === Attachment Theory === The Attachment theory, developed by John Bowlby from the 1950s through to the 1970s, has become a useful contemporary framework for understanding emotional development and regulation. It highlights the importance of interpersonal experiences as a source of individual differences in psychological resilience, emotion regulation, and adjustment as the result of child to caregiver relationships (Mikulincer et al 2006). An abundance of research dating back decades, suggests that attachment orientations and early relationship contexts can have a variety of implications and hypothesised links with emotional regulation, health, and the ability to form and maintain relationships (see figure 2 for the Attachment Theory two dimensional model). [[File:Attachment Theory Two Dimension Model.png|thumb|''Figure 2.'' The Attachment Theory two dimensional model]]Also central to Bowlby's theory (1969, 1973), is the idea that early caregivers play an important role in the ways the child organises emotional experience and acquires methods to regulate feelings of security. According to Bowlby, the goal to maintain a sense of security is universal, however strategies used to achieve it can vary with their attachment history. For example, when the caregiver is available and responsive to the child's distress signals, the child begins to understand that they can regulate distressing emotions and experiences (Cooper, 1998). [[File:Sandakan Sabah Angry-Child-01.jpg|thumb|''Figure 3.'' Child with an avoidant attachment orientation. ]] Under unpleasant circumstances, or in ACEs however, children can learn to associate the experience of distress with negative outcomes, and acquire the perception that distressing emotions cannot be efficiently regulated. Kobak and Sceery (1988) produced a concise summary of attachment theory's account of individual differences in emotion regulation: stating that, secure individuals are able to acknowledge and manage negative emotions, avoidant individuals try not to acknowledge negative emotions (see figure 3) and without fully acknowledging the reasons, can respond emotionally, and anxious individuals are highly emotionally expressive, and are sometimes unable to regulate their emotions or respond according to personal interests or social norms. The consequences of each attachment style vary, for instance, insecure attachment with lower self-esteem and less self-confidence. According to Mikulincer & Shaver (2019), attachment-related individual differences in emotion regulation have been documented in behavioural and neuroscience studies, providing strong empirical support for Bowlby's attachment theory and its extending impacts on adult dispositions and relationships. For example, two major findings suggested that those with avoidant attachments can be fragile and prone to collapse under stress, and that attachment insecurities (anxiety and avoidance) are associated with deficits in neural structure associated with emotion regulation. === Social Learning Theory === The Social Learning Theory can provide valuable insights into the relationship between ACEs and emotion regulation. According to Bandura's 1977 publication on the Social Learning Theory, new patterns of behaviour are acquired through direct experience or by observing the behaviour of others. This form of learning can be governed by rewards and punishments that follow any given consequence. It is commonly believed that these responses are automatically and unconsciously strengthened by their immediate consequences. Through modelling behaviour, children can learn emotional responses and coping strategies by observing the behaviours of caregivers and peers, for example by witnessing unhealthy emotional regulation such as aggression in response the stress, they may imitate these behaviours. Regulating emotions in maladaptive ways can also be the result of social contexts, such as neglect of violence, where there is no positive role model for emotional regulation. Bandura's concept of self-efficacy can also play a role, where children who experience ACEs, may develop low self-efficacy in regards to their ability to manage emotions (Bandura, 1977). According to Delaney (2006), maltreated children often display significant dysregulation in regards to their experience and expression of emotions, partially due to their reduced capacity to recognise social cues and emotional expression. === Family Systems Theory === Family Systems Theory (Minuchin, 1974) ties closely with the Social Learning Theory, as it recognises the importance of familial relationships as key components, or subsystems of a complex and multifaceted family system. Kramer (2014) and Whitemen et al (2011) suggested that sibling relationships provide important contexts for the development of children’s emotional understanding, particularly when it comes to learning and decoding others' emotions, anticipating the emotional responses of others, and the use of emotional understanding to build or impede relationships and influence the behaviours of others. Sibling interactions can enable children to learn how to label specific feelings, when it is appropriate to display these feelings, and how to detect them in others, which raises questions about the emotional development of those who did not grow up with siblings, learning emotional understanding through caregivers solely. === Polyvagal Theory === [[File:Polyvagal theory vagal.png|thumb|''Figure 4.'' Polyvagal Theory Tiers.]] (Porges & Buczynski, 2011) suggested the Polyvagal Theory of trauma, to be unique from other ways of understanding how the body responds to life threatening or stressful situations. It emphasises that the nervous system has multiple defence strategies, and will involuntarily respond is one of two ways, a mobilised flight or flight or an immobilised shut down defence strategy. [[File:Bullying Prevention in the United States.jpg|thumb|''Figure 3''. Adverse childhood experiences can extend beyond household dysfunction and include social factors, such as bullying and school-related issues.]] According to a systematic review (Balzarotti et al, 2017) on 135 applications of the Polyvagal Theory on emotional regulation in adulthood, trauma survivors can become stuck in the mobilised or immobilised state, as initial responses to threats might involve fighting back, hiding, fleeing, or shutting down (see figure 3). The ability to regulate the nervous system can become impaired, and opportunities for connection can be replaced with patterns of protection, programmed for threat and danger instead of safety and connection, making it difficult to build trust and feel safe. {{RoundBoxTop|theme=3}}Case Study Update: Using the knowledge you have gained, how might you explain Mason's struggles with his emotions and coping mechanisms? Critically reflect on the theories discussed, and think about the types of treatment styles that Mason could benefit from in the long term.{{RoundBoxBottom}} == Interventions and treatment approaches == === Trauma-informed care and community level strategies === According to Blodgett (2013), 25-35% of the population is affected by ACEs, calling for a multifactorial, public health approach consisting of trauma informed care, identification of at-risk individuals, and tailored strategies to accommodate for local circumstances in effort to prevent and mitigate the impacts of ACEs. Additionally, Hernandez (2020) highlighted the utility in implementing trauma informed care principles across community initiatives in addressing the broader impacts of ACEs. === Mindfulness for enhancing emotional awareness and regulation === Techniques for enhancing emotional awareness and control such as mindfulness, meditation and expressing writing have show significant promise in helping those with a history of ACEs observe their thoughts and feelings without judgement, and in improving outcomes (Korotana et al., 2016; Di Lemma et al., 2019). Some suggested benefits by Korotana et al (2016) include: * Increased awareness: enhance ability to recognise emotion patterns and triggers. * Improved control: lowered reactivity and impulsive behaviours, leading to more thoughtful emotional responses (Arbel et al., 2018; Soares et al., 2021). Arbel et al (2018) found that ACEs correlated with higher daily worry levels in adolescents, suggesting that early interventions to target worry reduction and emotional regulation could be beneficial for high ACE youth. Similarly, Korotana et al (2016) advocated for mindfulness-based interventions to support emotional regulation among adults with a history of ACEs. === Resilience building in cognitive behavioural therapy === Several studies have emphasised the significance of resilience building as a protective factor against the adverse effects of trauma (Hernandez, 2020; Di Lemma et al., 2019; Korotana et al., 2016). Key strategies to enhance resilience include: * Building relationships: encouraging supportive connections to facilitate feelings of belonging and emotional understanding. Kramer (2014) highlights the importance of sibling relationships as a potential for children's emotional growth, leading to positive developmental outcomes. * Promoting coping strategies: Resilience-building interventions focus on developing coping skills and emotional regulation techniques, which can help individuals manage stress and adversity. For example, Korotana et al (2016) highlighted to utility of cognitive behavioural therapies (CBT) in improving mental health outcomes for individuals with a history of ACEs. * Enhancing social and emotional competence: Programs aimed at strengthening social and emotional skills can aid in building resilience by equipping individuals with tools to navigate life challenges and can mitigate the impact of ACEs, facilitating healthier coping mechanisms (Hernandez, 2020; Di Lemma et al., 2019). === Family systems therapy and supporting parenting === * Supporting effective parenting: providing caregivers with training and resources to create a nurturing environment is vital for emotional growth (Hernandez, 2020). * Implementing accessible parenting programs: Community-based programs that offer support to parents, especially those from high-risk populations can lead to positive developmental outcomes (Di Lemma et al., 2019). * Family systems therapy: family systems therapies aim to restructure and establish family dynamics, communication patterns and boundaries, which can help families manage stressors (Ramage and Shipp, 2009). Kramer (2014), highlights the importance of maintaining sibling interactions as a means to foster emotional growth, which family systems therapy can support by facilitating healthy family dynamics and communication. '''Table 1.''' An overview of common components, interventions, settings, and protective factors associated with four approaches to prevent and mitigate the harm of ACEs as identified and based of Di Lemma et al (2019). {| class="wikitable" |+ !Approach !Key Components !Programs !Settings !Protective Factors |- |'''Supporting Parenting''' | * Supporting, teaching and empowering parents to build positive relationships and attachments with the child. | * Parenting interventions | * Home * School * Community | * Healthy parent-child attachment * Parental involvement |- |'''Building Relationships & Resilience''' | * Building positive relationships. * Behavioural regulation * Promoting wellbeing, mental health and a healthy lifestyle. * Holistic approaches to coping with stress. * Multi-agency approaches. | * School-based interventions * Mentoring | * School * Community | * Strengthened social and emotional competency * Supportive relationships and healthy role models outside from parents |- |'''Early Identification of Adversity''' | * Increased awareness * Specific early actions, i.e. referrals to services, | * Early identification of adversities | * Home * School * Welfare * Community | * Early intervention access |- |'''Responding to Trauma''' | * Psychological and pharmacological treatments * Tailored treatments to support families, parents, and children | * psychotherapeutic interventions. | * Home * School * Community | * Resilience building and coping strategies * positive community and family ties. |} ==Conclusion== Based on psychological theory and empirical research findings, the general understanding is that ACEs, encompassing a range of negative and traumatic childhood experiences, can significantly hinder and disrupt the development of emotion regulation. Empirical research findings suggest a strong link between ACEs and difficulties in managing emotions, such as experiences adversities link heightened emotional reactivity and maladaptive coping mechanisms. Theoretical perspectives such as the Attachment Theory, offer an understanding of how insecure attachments formed in early childhood can impede emotional regulation, while the Social Learning Theory suggests that children can obtain emotional responses through observing their caregivers. Family Systems Theory highlights the influence for family dynamics, communication, and boundaries on emotional understanding and expression, and Polyvagal Theory explains how the autonomic nervous system reacts to initial ACEs and later challenges, impacting emotional responses. Interventions such as trauma-informed care, mindfulness and CBT with a focus on resilience building, are necessary in mitigating the adverse effects of ACEs, facilitating emotion awareness, and promoting healthier coping strategies. Early identification and support also make a profound difference in a child's life, potentially altering their developmental trajectory and improving their overall well being. Ultimately, understanding the pervasive impact of ACEs and implementing effective, tailored interventions can work to enhance emotional functioning, providing support for those navigating the challenges that stem from their early life experiences. ==See also== *[[w:https://en.wikipedia.org/wiki/Emotional_self-regulation|Adverse Childhood Experiences and Risk-Taking Motivations: How do ACEs Affect Risk-Taking Motivation?]] (Book chapter, 2024) *[[w:https://en.wikipedia.org/wiki/Emotional_self-regulation|Emotional Self-Regulation]] (Wikipedia) * [[Motivation and emotion/Book/2013/Emotional self-regulation|Emotional Self-Regulation: What is Self-Regulation, Why is it Important, and how can it be Developed?]] (Book chapter, 2013) * [[Motivation and emotion/Book/2014/Emotional regulation through meditation|Emotional Regulation through Meditation: How can Meditation help with Emotional Regulation?]] (Book chapter, 2014) ==References== {{Hanging indent|1= Austin, M. A., Riniolo, T. C., Porges, S. W. (2007). Borderline personality disorder and emotion regulation: Insights from the Polyvagal Theory. Brain and Cognition., 65(1). https://doi.org/10.1016/j.bandc.2006.05.007 Amarante, J. (2024). Adverse childhood experiences and adolescent substance use: The roles of emotion regulation and attachment security (Order No. 31146865). Available from ProQuest One Academic. (3037345048). Retrieved from https://www.proquest.com/dissertations-theses/adverse-childhood-experiences-adolescent/docview/3037345048/se-2 Arbel, R., Schacter, H. L., Kazmierski, K. F., Daspe, M. È., & Margolin, G. (2018). Adverse childhood experiences, daily worries, and positive thoughts: A daily diary multi‐wave study. British Journal of Clinical Psychology, 57(4), 514-519. Balzarotti. (2017). Cardiac vagal control as a marker of emotion regulation in healthy adults: A review. Biological Psychology., 130. https://doi.org/10.1016/j.biopsycho.2017.10.008 Bandura, A. (1977). , , and View all authors and affiliations https://doi.org/10.1177/10596011770020031 Boullier, M., & Blair, M. (2018). Adverse childhood experiences. Paediatrics and Child Health, 28(3), 132-137. Bowlby, J. (1958). The nature of the child's tie to his mother. International Journal of Psycho-Analysis, XXXIX, 1-23 Bowlby, J. (1969). Attachment and loss, Vol. I: Attachment. New York: Basic Books Brumariu. (2015). Parent-child attachment and emotion regulation. New Directions for Child and Adolescent Development., 2015(148). https://doi.org/10.1002/cad.20098 Burchfield, S. R. (1979). The stress response: A new perspective. Psychosomatic Medicine, 41(8), 661-672. Cleveland Clinic. (2023). Adverse Childhood Experiences (ACEs) & Childhood Trauma. Cleveland Clinic. https://my.clevelandclinic.org/health/symptoms/24875-adverse-childhood-experiences-ace Chefetz, R. A. (2015). Intensive psychotherapy for persistent dissociative processes: The fear of feeling real. Norton. Cooper. (1998). Attachment styles, emotion regulation, and adjustment in adolescence. Journal of Personality and Social Psychology., 74(5). https://doi.org/10.1037/0022-3514.74.5.1380 Delaney. (2006). Following the affect: Learning to observe emotional regulation. Journal of Child and Adolescent Psychiatric Nursing., 19(4). https://doi.org/10.1111/j.1744-6171.2006.00069.x Di Lemma L.C.G., Davies A.R., Ford K., Hughes K., Homolova L., Gray B and Richardson G. (2019). Responding to Adverse Childhood Experiences: An evidence review of interventions to prevent and address adversity across the life course. Public Health Wales, Cardiff and Bangor University, Wrexham, ISBN 978-1-78986-035-1. Ehrenthal. (2018). Attachment-related regulatory processes moderate the impact of adverse childhood experiences on stress reaction in borderline personality disorder. Personality Disorders., 32(Supplement). https://doi.org/10.1521/pedi.2018.32.supp.93 Felitti, V. J., Anda, R. F., Nordenberg, D., Williamson, D. F., Spitz, A. M., Edwards, V., & Marks, J. S. (1998). Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The Adverse Childhood Experiences (ACE) Study. American journal of preventive medicine, 14(4), 245-258. Goodhill G. J. (2018). Theoretical Models of Neural Development. iScience, 8, 183–199. https://doi.org/10.1016/j.isci.2018.09.017 Haeyen. (2024). A theoretical exploration of polyvagal theory in creative arts and psychomotor therapies for emotion regulation in stress and trauma. Frontiers in Psychology., 15. https://doi.org/10.3389/fpsyg.2024.1382007 Hernandez, N. (2020). A Systematic Review of Prevention and Mitigation Recommendations for Adverse Childhood Experiences (ACEs). Hughes, K., Bellis, M. A., Hardcastle, K. A., Sethi, D., Butchart, A., Mikton, C., Jones, L., & Dunne, M. P. (2017). The effect of multiple adverse childhood experiences on health: A systematic review and meta-analysis. The Lancet Public Health, 2(8), e356–366. https://doi.org/10.1016/S2468- 2667(17)30118-4 Kobak, R. R., & Sceery, A. (1988). Attachment in late adolescence: Working models, affect regulation, and representations of self and others. Child Development, 59, 135-146. Korotana, L. M., Dobson, K. S., Pusch, D., & Josephson, T. (2016). A review of primary care interventions to improve health outcomes in adult survivors of adverse childhood experiences. Clinical psychology review, 46, 59-90. https://doi.org/10.1016/j.cpr.2016.04.007 Kramer. (2014). Learning emotional understanding and emotion regulation through sibling interaction. Early Education and Development., 25(2). https://doi.org/10.1080/10409289.2014.838824 Mikulincer, M., & Shaver, P. R. (2019). Attachment orientations and emotion regulation. Current opinion in psychology, 25, 6-10. Mikulincer, M., Shaver, P. R., & Horesh, N. (2006). Attachment bases of emotion regulation and posttraumatic adjustment. Poole, J. C., Dobson, K. S., & Pusch, D. (2018). Do adverse childhood experiences predict adult interpersonal difficulties? The role of emotion dysregulation. Child Abuse & Neglect, 80, 123–133. https://doi.org/10.1016/j .chiabu.2018.03.006 Porges, S. W., & Buczynski, R. (2011). The polyvagal theory for treating trauma. Webinar, June, 15, 2012. Snyder. (2024). Adverse childhood experiences and insecure attachment: The indirect effects of dissociation and emotion regulation difficulties. Psychological Trauma : Theory, Research, Practice and Policy., 16(S1). https://doi.org/10.1037/tra0001532 Soares, S., Rocha, V., Kelly-Irving, M., Stringhini, S., & Fraga, S. (2021). Adverse childhood events and health biomarkers: a systematic review. Frontiers in public health, 9, 649825. Ye. (2024). The impact of adverse childhood experiences on depression: the role of insecure attachment styles and emotion dysregulation strategies. Current Psychology : Research & Reviews., 43(5). https://doi.org/10.1007/s12144-023-04613-1 }} ==External links== * [https://developingchild.harvard.edu/resources/aces-and-toxic-stress-frequently-asked-questions/ ACEs and Toxic Stress: Frequently Asked Questions] (Harvard University) * [https://www.unicef.org/press-releases/nearly-400-million-young-children-worldwide-regularly-experience-violent-discipline Nearly 400 million young children worldwide regularly experience violent discipline at home – UNICEF](UNICEF Global Child Abuse Estimates) [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Children]] [[Category:Motivation and emotion/Book/Emotional self-regulation]] [[Category:Motivation and emotion/Book/Trauma]] rxgzsc9t9gjv1h5x2jp6fkrniuwr7ji 828 308015 2844895 2842889 2026-11-08T21:06:42Z Grufo 1192007 Update from [[d:Special:GoToLinkedPage/mediawikiwiki/Q122696746|master]] using [[mw:Synchronizer| #Synchronizer]] 2844895 Scribunto text/plain require[[strict]] --- --- --- PRIVATE ENVIRONMENT --- --- ________________________________ --- --- --- --[[ Abstract utilities ]]-- ---------------------------- -- Helper function for `string.gsub()` (for managing zero-padded numbers) local function zero_padded (str) return ('%03d%s'):format(#str, str) end -- Helper function for `table.sort()` (for natural sorting) local function natural_sort (var1, var2) return var1:gsub('%d+', zero_padded) < var2:gsub('%d+', zero_padded) end -- Return a copy or a reference to a table local function copy_or_ref_table (src, refonly) if refonly then return src end local newtab = {} for key, val in pairs(src) do newtab[key] = val end return newtab end -- Copy at most N items (of all kinds) from `src` to `dest` and return `dest` local function copy_table_maxn (dest, src, len) local idx = 1 for key, val in pairs(src) do dest[key], idx = val, idx + 1 if idx > len then break end end return dest end -- Remove some numeric elements from a table, shifting everything to the left local function remove_numeric_keys (tbl, idx, len) local cache, tmp = {}, idx + len - 1 for key, val in pairs(tbl) do if type(key) == 'number' and key >= idx then if key > tmp then cache[key - len] = val end tbl[key] = nil end end for key, val in pairs(cache) do tbl[key] = val end end -- Make a reduced copy of a table (shifting in both directions if necessary) local function copy_table_reduced (tbl, idx, len) local ret, tmp = {}, idx + len - 1 if idx > 0 then for key, val in pairs(tbl) do if type(key) ~= 'number' or key < idx then ret[key] = val elseif key > tmp then ret[key - len] = val end end elseif tmp > 0 then local nshift = 1 - idx for key, val in pairs(tbl) do if type(key) ~= 'number' then ret[key] = val elseif key > tmp then ret[key - tmp] = val elseif key < idx then ret[key + nshift] = val end end else for key, val in pairs(tbl) do if type(key) ~= 'number' or key > tmp then ret[key] = val elseif key < idx then ret[key + len] = val end end end return ret end -- Make an expanded copy of a table (shifting in both directions if necessary) local function copy_table_expanded (tbl, idx, len) local ret, tmp = {}, idx + len - 1 if idx > 0 then for key, val in pairs(tbl) do if type(key) ~= 'number' or key < idx then ret[key] = val else ret[key + len] = val end end elseif tmp > 0 then local nshift = idx - 1 for key, val in pairs(tbl) do if type(key) ~= 'number' then ret[key] = val elseif key > 0 then ret[key + tmp] = val elseif key < 1 then ret[key + nshift] = val end end else for key, val in pairs(tbl) do if type(key) ~= 'number' or key > tmp then ret[key] = val else ret[key - len] = val end end end return ret end -- Given a table, create two new tables containing the sorted list of keys local function get_sorted_key_list (tbl, sort_fn) local nums, words, nn, nw = {}, {}, 1, 1 for key, val in pairs(tbl) do if type(key) == 'number' then nums[nn], nn = key, nn + 1 else words[nw], nw = key, nw + 1 end end table.sort(nums) table.sort(words, sort_fn) return nums, words, nn - 1, nw - 1 end -- Parse a parameter name string and return it as a string or a number local function get_param_name (par_str) local ret = par_str:match'^%s*(.-)%s*$' if ret ~= '0' and ret:find'^%-?[1-9]%d*$' == nil then return ret end return tonumber(ret) end -- Move a key from a table to another, but only if under a different name and -- always parsing numeric strings as numbers local function steal_if_renamed (val, src, skey, dest, dkey) local realkey = get_param_name(dkey) if skey ~= realkey then dest[realkey], src[skey] = val, nil end end --[[ Public strings ]]-- ------------------------ -- Special match keywords (functions and modifiers MUST avoid these names) local mkeywords = { ['or'] = 0, pattern = 1, plain = 2, strict = 3 } -- Sort functions (functions and modifiers MUST avoid these names) local sortfunctions = { alphabetically = false, naturally = natural_sort } -- Callback styles for the `mapping_*` and `renaming_*` class of modifiers -- (functions and modifiers MUST avoid these names) --[[ Meanings of the columns: col[1] = Loop type (0-3) col[2] = Number of module arguments that the style requires (1-3) col[3] = Minimum number of sequential parameters passed to the callback col[4] = Name of the callback parameter where to place each parameter name col[5] = Name of the callback parameter where to place each parameter value col[6] = Argument in the modifier's invocation that will override `col[4]` col[7] = Argument in the modifier's invocation that will override `col[5]` A value of `-1` indicates that no meaningful value is stored (i.e. `nil`) ]]-- local mapping_styles = { names_and_values = { 3, 2, 2, 1, 2, -1, -1 }, values_and_names = { 3, 2, 2, 2, 1, -1, -1 }, values_only = { 1, 2, 1, -1, 1, -1, -1 }, names_only = { 2, 2, 1, 1, -1, -1, -1 }, names_and_values_as = { 3, 4, 0, -1, -1, 2, 3 }, names_only_as = { 2, 3, 0, -1, -1, 2, -1 }, values_only_as = { 1, 3, 0, -1, -1, -1, 2 }, blindly = { 0, 2, 0, -1, -1, -1, -1 } } -- Memory slots (functions and modifiers MUST avoid these names) local memoryslots = { h = 'header', f = 'footer', i = 'itersep', l = 'lastsep', n = 'ifngiven', p = 'pairsep', s = 'oxfordsep' } -- Possible trimming modes for the `parsing` modifier local trim_parse_opts = { trim_none = { false, false }, trim_positional = { false, true }, trim_named = { true, false }, trim_all = { true, true } } -- Possible string modes for the iteration separator in the `parsing` and -- `reinterpreting` modifiers local isep_parse_opts = { splitter_pattern = false, splitter_string = true } -- Possible string modes for the key-value separator in the `parsing` and -- `reinterpreting` modifiers local psep_parse_opts = { setter_pattern = false, setter_string = true } -- Possible position references for the `splicing` modifier local position_references = { add_nothing = 0, add_smallest_number = 1, add_last_of_sequence = 2, add_largest_number = 3 } -- Possible modes for the `reassigning` modifier local a_modes = { transfer = 0, clone = 1, rename = 2, copy = 3, sacrifice = 4, provide = 5, spare = 7 } -- Functions and modifiers MUST avoid these names too: `here`, `in_substack`, -- `let`, `expose`, `use`, `with_flushed_glue`, `without_flushed_glue` -- `without_sorting` --[[ Private constants ]]-- --------------------------- -- Hard-coded name of the module (to avoid going through `frame:getTitle()`) local modulename = 'Module:Params' -- The functions listed here declare that they don't need the -- `frame:getParent().args` metatable to be copied into a regular table; if -- they are modifiers they also guarantee that they will make their own -- (modified) copy available local refparams = { call_for_each_group = true, combining = true, combining_by_calling = true, combining_values = true, concat_and_call = true, concat_and_invoke = true, concat_and_magic = true, count = true, grouping_by_calling = true, mixing_names_and_values = true, keeping_at_most = true, renaming_by_mixing = true, renaming_to_sequence = true, renaming_to_uppercase = true, renaming_to_lowercase = true, shifting = true, splicing = true, value_of = true, with_name_matching = true } -- Maximum number of numeric parameters that can be filled, if missing (we -- chose an arbitrary number for this constant; you can discuss about its -- optimal value at Module talk:Params) local maxfill = 1024 -- The private table of functions local library = {} -- Functions and modifiers that can only be invoked in first position local static_iface = {} --[[ Private functions ]]-- --------------------------- -- Create a new context local function context_new (child_frame, first_fn_name) local main_frame, tpipe = child_frame:getParent(), { first_fn_name } for key, val in pairs(child_frame.args) do if type(key) == 'number' and key > 0 then tpipe[key + 1] = val else tpipe[key] = val end end return { frame = main_frame, pipe = tpipe, oparams = main_frame.args, firstposonly = static_iface, iterfunc = pairs, fnpos = 1, sorttype = 0, n_parents = 0, n_children = 0, n_available = maxfill } end -- Move to the next action within the user-given list local function context_iterate (ctx, next_fn_pos, trimmed_fname) local fname = trimmed_fname or ctx.pipe[next_fn_pos] and ctx.pipe[next_fn_pos]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ': You must specify a function to call', 0) end if library[fname] == nil then if ctx.firstposonly[fname] == nil then error(modulename .. ': The function ‘' .. fname .. '’ does not exist', 0) else error(modulename .. ': The ‘' .. fname .. '’ directive can only appear in first position', 0) end end ctx.fnpos = next_fn_pos return library[fname] end -- Main loop local function main_loop (ctx, start_with) local fn = start_with repeat fn = fn(ctx) until not fn if ctx.n_parents > 0 then error(modulename .. ': One or more ‘merging_substack’ directives are missing', 0) end if ctx.n_children > 0 then error(modulename .. ', For some of the snapshots either the ‘flushing’ directive is missing or a group has not been properly closed with ‘merging_substack’', 0) end end -- Load a `setting`-like directive string into the `dest` table local function set_strings_from_opts (dest, opts, offs) local cmd if opts[offs] == nil then return offs - 1 end cmd = opts[offs]:gsub('%s+', ''):gsub('/+', '/'):match'^/*(.*[^/])' if cmd == nil then return offs end local vname, chr local amap, sep, argc = {}, string.byte('/'), offs + 1 for idx = 1, #cmd do chr = cmd:byte(idx) if chr == sep then for key, val in ipairs(amap) do dest[val], amap[key] = opts[argc], nil end argc = argc + 1 else vname = memoryslots[string.char(chr)] if vname == nil then error(modulename .. ', ‘setting’: Unknown slot ‘' .. string.char(chr) .. '’', 0) end table.insert(amap, vname) end end for key, val in ipairs(amap) do dest[val] = opts[argc] end return argc end -- Add a new stack of parameters to `ctx.children` local function new_substack (ctx) local currsnap, newparams = ctx.n_children + 1, {} if ctx.children == nil then ctx.children = { newparams } else ctx.children[currsnap] = newparams end ctx.n_children = currsnap return newparams end -- Parse a raw argument containing a `sortfunctions` directive, or -- `'without_sorting'`, or `nil` local function load_sort_opt (raw_arg) local trarg if raw_arg ~= nil then trarg = raw_arg:match'^%s*(.*%S)' end if trarg == nil then return nil, 1, false, nil end if trarg == 'without_sorting' then return nil, 2, false, nil end local tmp = sortfunctions[trarg] if tmp == nil then return nil, 1, false, trarg end return tmp or nil, 2, true, nil end -- Parse optional user arguments of type `...|[let/use]|[...]|[let/use]|[...]| -- [number of additional parameters]|[parameter 1]|[parameter 2]|[...]` local function load_child_opts (src, start_from, append_after, params) local tnamed, tmp1, tmp2 local pin, tbl, mem = start_from, {}, {} while src[pin] ~= nil and src[pin + 1] ~= nil do tmp1 = src[pin]:match'^%s*(.*%S)' if tmp1 == 'let' and src[pin + 2] ~= nil then tmp1 = get_param_name(src[pin + 1]) tbl[tmp1], pin = src[pin + 2], pin + 3 --[[ elseif tmp1 == 'expose' then tmp1 = get_param_name(src[pin + 1]) tmp2 = params[tmp1] mem[tmp1], tbl[tmp1], pin = tmp2, tmp2, pin + 2 ]]-- elseif tmp1 == 'use' and src[pin + 2] ~= nil then tmp1 = get_param_name(src[pin + 2]) tmp2 = params[tmp1] mem[tmp1], tbl[get_param_name(src[pin + 1])], pin = tmp2, tmp2, pin + 3 else break end end local tnew = copy_or_ref_table(params, next(mem) == nil) for key in pairs(mem) do tnew[key] = nil end if pin ~= start_from then tnamed, tbl = tbl, {} end tmp1 = tonumber(src[pin]) if tmp1 ~= nil and math.floor(tmp1) == tmp1 then if tmp1 < 0 then tmp1 = -1 end tmp2 = append_after - pin for idx = pin + 1, pin + tmp1 do tbl[idx + tmp2] = src[idx] end pin = pin + tmp1 + 1 end if tnamed ~= nil then for key, val in pairs(tnamed) do tbl[key] = val end end return tbl, pin, tnew, mem end -- Load the optional arguments of some of the `mapping_*` and `renaming_*` -- class of modifiers local function load_callback_opts (src, start_from, default_style, params) local style, shf local tmp = src[start_from + 1] if tmp ~= nil then style = mapping_styles[tmp:match'^%s*(.-)%s*$'] end if style == nil then style, shf = default_style, start_from - 1 else shf = start_from end local n_exist, karg, varg = style[3], style[4], style[5] tmp = style[6] if tmp > -1 then karg = src[tmp + shf]:match'^%s*(.-)%s*$' if karg == '0' or karg:find'^%-?[1-9]%d*$' ~= nil then karg = tonumber(karg) n_exist = math.max(n_exist, karg) end end tmp = style[7] if tmp > -1 then varg = src[tmp + shf]:match'^%s*(.-)%s*$' if varg == '0' or varg:find'^%-?[1-9]%d*$' ~= nil then varg = tonumber(varg) n_exist = math.max(n_exist, varg) end end tmp = style[1] local dest, argc, tnew, mem = load_child_opts(src, style[2] + shf, n_exist, params) if (tmp == 3 or tmp == 2) and dest[karg] ~= nil then tmp = tmp - 2 end if (tmp == 3 or tmp == 1) and dest[varg] ~= nil then tmp = tmp - 1 end return dest, argc, tmp, karg, varg, tnew, mem end -- Parse the arguments of some of the `mapping_*` and `renaming_*` class of -- modifiers local function load_replace_args (opts, offs, whoami) if opts[offs + 1] == nil then error(modulename .. ', ‘' .. whoami .. '’: No pattern string was given', 0) end if opts[offs + 2] == nil then error(modulename .. ', ‘' .. whoami .. '’: No replacement string was given', 0) end local tn, flg local ptn, repl, nmax, argc = opts[offs + 1], opts[offs + 2], tonumber(opts[offs + 3]), 3 if nmax ~= nil then argc = 4 elseif opts[offs + 3] ~= nil then tn = opts[offs + 3]:match'^%s*(.*%S)' if tn == nil then argc = 4 end end if tn == nil and opts[offs + argc] ~= nil then tn = opts[offs + argc]:match'^%s*(.*%S)' end if tn ~= nil then flg = mkeywords[tn] if flg ~= nil then tn = nil end end if flg == 0 then flg = nil elseif flg ~= nil then argc = argc + 1 end return ptn, repl, nmax, flg, offs + argc, (nmax ~= nil and nmax < 1) or (flg == 3 and ptn == repl), tn end -- Parse the arguments of the `with_*_matching` class of modifiers local function load_pattern_args (opts, offs, whoami) local tn, kwid local ptns, arg, state, nptns, idx = {}, opts[offs + 1], 0, 0, offs + 2 while arg ~= nil do if state == 0 then nptns, state = nptns + 1, -1 ptns[nptns] = { arg, false, false } else tn = arg:match'^%s*(.*%S)' kwid = tn and mkeywords[tn] if kwid == nil or (state > 0 and kwid > 0) then break else state = kwid if state > 1 then ptns[nptns][2] = true end if state == 3 then ptns[nptns][3] = true end end end arg, idx = opts[idx], idx + 1 end if state == 0 then error(modulename .. ', ‘' .. whoami .. '’: No pattern was given', 0) end return ptns, nptns, idx - 1, kwid == nil and tn or nil end -- Load the optional arguments of the `parsing`, `reinterpreting` and -- `evaluating` modifiers local function load_parse_opts (opts, offs, isp, psp) local tn, tmp local optslots, noptslots, argc, trimn, trimu, iplain, pplain = { true, true, true }, 3, offs, true, false, true, true repeat noptslots, tmp = noptslots - 1, opts[argc] tn = tmp and tmp:match'^%s*(.*%S)' if tn == nil then break end if optslots[1] ~= nil and trim_parse_opts[tn] ~= nil then tmp = trim_parse_opts[tn] trimn, trimu, optslots[1] = tmp[1], tmp[2], nil elseif optslots[2] ~= nil and isep_parse_opts[tn] ~= nil then argc = argc + 1 iplain, isp, optslots[2] = isep_parse_opts[tn], opts[argc], nil elseif optslots[3] ~= nil and psep_parse_opts[tn] ~= nil then argc = argc + 1 pplain, psp, optslots[3] = psep_parse_opts[tn], opts[argc], nil else break end argc, tn = argc + 1, nil until noptslots < 1 return isp, iplain, psp, pplain, trimn, trimu, argc, tn end -- Map parameters' values using a custom callback and a referenced table local value_maps = { [0] = function (tbl, margs, karg, varg, fn) for key in pairs(tbl) do tbl[key] = fn() end end, [1] = function (tbl, margs, karg, varg, fn) for key, val in pairs(tbl) do margs[varg] = val tbl[key] = fn() end end, [2] = function (tbl, margs, karg, varg, fn) for key in pairs(tbl) do margs[karg] = key tbl[key] = fn() end end, [3] = function (tbl, margs, karg, varg, fn) for key, val in pairs(tbl) do margs[karg], margs[varg] = key, val tbl[key] = fn() end end } -- Private table for `map_names()` local name_thieves = { [0] = function (cache, tbl, rargs, karg, varg, fn) for key, val in pairs(tbl) do steal_if_renamed(val, tbl, key, cache, fn()) end end, [1] = function (cache, tbl, rargs, karg, varg, fn) for key, val in pairs(tbl) do rargs[varg] = val steal_if_renamed(val, tbl, key, cache, fn()) end end, [2] = function (cache, tbl, rargs, karg, varg, fn) for key, val in pairs(tbl) do rargs[karg] = key steal_if_renamed(val, tbl, key, cache, fn()) end end, [3] = function (cache, tbl, rargs, karg, varg, fn) for key, val in pairs(tbl) do rargs[karg], rargs[varg] = key, val steal_if_renamed(val, tbl, key, cache, fn()) end end } -- Map parameters' names using a custom callback and a referenced table local function map_names (tbl, rargs, karg, varg, looptype, fn) local cache = {} name_thieves[looptype](cache, tbl, rargs, karg, varg, fn) for key, val in pairs(cache) do tbl[key] = val end end -- Return a new table that contains `src` regrouped according to the numeric -- suffixes in its keys local function make_groups (src) -- NOTE: `src` might be the original metatable! local prefix, gid local groups = {} for key, val in pairs(src) do -- `key` must only be a string or a number... if type(key) == 'string' then prefix, gid = key:match'^%s*(.-)%s*(%-?%d*)%s*$' gid = tonumber(gid) or '' else prefix, gid = '', key end if groups[gid] == nil then groups[gid] = {} end if prefix == '0' or prefix:find'^%-?[1-9]%d*$' ~= nil then prefix = tonumber(prefix) if prefix < 1 then prefix = prefix - 1 end end groups[gid][prefix] = val end return groups end -- Split into parts a string containing the `$#` and `$@` placeholders and -- return the information as a skeleton table, a canvas table and a length local function parse_placeholder_string (target) local skel, canvas, idx, s_pos, e_pos = {}, {}, 1, 1, string.find(target, '%$[@#]', 1, false) while e_pos ~= nil do canvas[idx], skel[idx + 1] = target:sub(s_pos, e_pos - 1), target:sub(e_pos, e_pos + 1) == '$@' idx, s_pos = idx + 2, e_pos + 2 e_pos = string.find(target, '%$[@#]', s_pos, false) end if (s_pos > target:len()) then idx = idx - 1 else canvas[idx] = target:sub(s_pos) end return skel, canvas, idx end -- Populate a table by parsing a parameter string (heavy lifting for `parsing`, -- `reinterpreting` and `evaluating`) local function parse_parameter_string (tbl, str, isp, ipl, psp, ppl, trn, tru) local key, val, spos1, spos2, pos1, pos2 local pos3, idx, lenplone = 0, 1, #str + 1 if isp == nil or isp == '' then if psp == nil or psp == '' then if tru then tbl[idx] = str:match'^%s*(.-)%s*$' else tbl[idx] = str end return end spos1, spos2 = str:find(psp, 1, ppl) if spos1 == nil then key = idx if tru then val = str:match'^%s*(.-)%s*$' else val = str end else key = get_param_name(str:sub(1, spos1 - 1)) val = str:sub(spos2 + 1) if trn then val = val:match'^%s*(.-)%s*$' end end tbl[key] = val return end if psp == nil or psp == '' then repeat pos1 = pos3 + 1 pos2, pos3 = str:find(isp, pos1, ipl) val = str:sub(pos1, (pos2 or lenplone) - 1) if tru then val = val:match'^%s*(.-)%s*$' end tbl[idx], idx = val, idx + 1 until pos2 == nil return end repeat pos1 = pos3 + 1 pos2, pos3 = str:find(isp, pos1, ipl) val = str:sub(pos1, (pos2 or lenplone) - 1) spos1, spos2 = val:find(psp, 1, ppl) if spos1 == nil then key = idx if tru then val = val:match'^%s*(.-)%s*$' end idx = idx + 1 else key = get_param_name(val:sub(1, spos1 - 1)) val = val:sub(spos2 + 1) if trn then val = val:match'^%s*(.-)%s*$' end end tbl[key] = val until pos2 == nil return end -- Heavy lifting for `snapshotting` and `remembering` local function make_child (ctx, src, whoami) local len = tonumber(ctx.pipe[ctx.fnpos + 1]) if len == nil or len == 0 then local stack = new_substack(ctx) for key, val in pairs(src) do stack[key] = val end return len == nil and 1 or 2 end if len < 0 or math.floor(len) ~= len then error(modulename .. ', ‘' .. whoami .. '’: The number of parameters to copy must be an integer greater than zero', 0) end copy_table_maxn(new_substack(ctx), src, len) return 2 end -- Heavy lifting for `setting_by_flushing`, `combining` and `combining_values` local function set_strings_from_substack (ctx, dest, whoami) if ctx.n_children < 1 then error(modulename .. ', ‘' .. whoami .. '’: There are no substacks to flush', 0) end local currsnap = ctx.n_children local stack = ctx.children[currsnap] for key, val in pairs(memoryslots) do if stack[key] ~= nil then dest[val] = stack[key] end end ctx.children[currsnap], ctx.n_children = nil, currsnap - 1 end -- Heavy lifting for `combining` and `combining_values` local function combine_parameters (ctx, keyval_fn, whoami) -- NOTE: `ctx.params` might be the original metatable! This function -- MUST create a copy of it before returning local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘' .. whoami .. '’: No parameter name was provided', 0) end local argc local tbl, vars = ctx.params, {} local sortfn, ivar0, dosort, tmp = load_sort_opt(opts[offs + 2]) if ivar0 == 2 then tmp = opts[offs + 3] ~= nil and opts[offs + 3]:match'^%s*(.*%S)' end ivar0 = ivar0 + offs if tmp == 'with_flushed_glue' then ivar0 = ivar0 + 1 argc = set_strings_from_opts(vars, opts, ivar0 + 1) set_strings_from_substack(ctx, vars, whoami) else if tmp == 'without_flushed_glue' then ivar0 = ivar0 + 1 end argc = set_strings_from_opts(vars, opts, ivar0 + 1) end if argc < ivar0 then error(modulename .. ', ‘' .. whoami .. '’: No setting directive was given', 0) end if next(tbl) == nil then if vars.ifngiven ~= nil then ctx.params = { [get_param_name(opts[offs + 1])] = vars.ifngiven } elseif tbl == ctx.oparams then ctx.params = {} end return argc + 1 end local cache, len if dosort then local words cache, words, len, tmp = get_sorted_key_list(tbl, sortfn) for idx = 1, tmp do cache[len + idx] = words[idx] end len = len + tmp else cache, len = {}, 1 for key in pairs(tbl) do cache[len], len = key, len + 1 end len = len - 1 end local pmap, nss, kvs, pps = {}, 0, vars.pairsep or '', vars.itersep or '' for idx = 1, len do tmp, pmap[nss + 1] = cache[idx], pps pmap[nss + 2] = keyval_fn(tmp, tbl[tmp], kvs) nss = nss + 2 end tmp = vars.oxfordsep or vars.lastsep if tmp ~= nil and nss > 4 then pmap[nss - 1] = tmp elseif nss > 2 and vars.lastsep ~= nil then pmap[nss - 1] = vars.lastsep end pmap[1] = vars.header or '' if vars.footer ~= nil then pmap[nss + 1] = vars.footer end ctx.params = { [get_param_name(opts[offs + 1])] = table.concat(pmap) } return argc + 1 end -- Concatenate the numeric keys from the table of parameters to the numeric -- keys from the table of options; non-numeric keys from the table of options -- will prevail over colliding non-numeric keys from the table of parameters local function concat_params (ctx, offs) local tbl, retval, cache, nmax = ctx.params, {}, {}, 0 for key, val in pairs(ctx.pipe) do if type(key) == 'number' then if key < 1 then cache[key] = val elseif key > offs then cache[key - offs] = val end if key > nmax then nmax = key end else cache[key] = val end end nmax = nmax - offs if ctx.subset == 1 then -- We need only the sequence for key, val in ipairs(tbl) do retval[key + nmax] = val end else if ctx.subset == -1 then for key in ipairs(tbl) do tbl[key] = nil end end for key, val in pairs(tbl) do if type(key) == 'number' and key > 0 then retval[key + nmax] = val else retval[key] = val end end end for key, val in pairs(cache) do retval[key] = val end return retval end -- Flush the parameters by calling a custom function for each value (after this -- function has been invoked `ctx.params` will be no longer usable) local function flush_params (ctx, fn) local tmp local tbl = ctx.params if ctx.subset == -1 then for key, val in ipairs(tbl) do tbl[key] = nil end elseif ctx.subset == 1 then if ctx.pins == nil then for key, val in ipairs(tbl) do fn(key, val) end return end tmp = {} for key, val in ipairs(tbl) do tmp[key] = val end tbl = tmp end if ctx.pins ~= nil then local marker = ctx.sorttype < 1 and ctx.subset ~= -1 or nil for idx = 1, #ctx.pins do tmp = ctx.pins[idx] if tbl[tmp] ~= nil then fn(tmp, tbl[tmp]) tbl[tmp] = marker end end if ctx.subset == 1 then for key, val in ipairs(tbl) do if val ~= true then fn(key, val) end end return end end if ctx.sorttype > 0 then local nums, words, nn, nw = get_sorted_key_list(tbl, natural_sort) if ctx.sorttype == 2 then for idx = 1, nw do fn(words[idx], tbl[words[idx]]) end for idx = 1, nn do fn(nums[idx], tbl[nums[idx]]) end return end for idx = 1, nn do fn(nums[idx], tbl[nums[idx]]) end for idx = 1, nw do fn(words[idx], tbl[words[idx]]) end return end if ctx.subset == -1 or ctx.pins == nil then for key, val in ipairs(tbl) do fn(key, val) tbl[key] = nil end for key, val in pairs(tbl) do fn(key, val) end return end for key, val in ipairs(tbl) do if val ~= true then fn(key, val) end tbl[key] = nil end for key, val in pairs(tbl) do if val ~= true then fn(key, val) end end end -- Flush the parameters by calling one of two custom functions for each value -- (after this function has been invoked `ctx.params` will be no longer usable) local function mixed_flush_params (ctx, fn_seq, fn_oth) if ctx.subset == 1 then flush_params(ctx, fn_seq) return end if ctx.subset == -1 then flush_params(ctx, fn_oth) return end local tbl = ctx.params if ctx.pins == nil and ctx.sorttype < 1 then for key, val in ipairs(tbl) do fn_seq(key, val) tbl[key] = nil end for key, val in pairs(tbl) do fn_oth(key, val) end return end local tseq = {} for key, val in ipairs(tbl) do tseq[key] = val end if ctx.pins ~= nil then local tmp local marker = ctx.sorttype < 1 or nil for idx = 1, #ctx.pins do tmp = ctx.pins[idx] if tseq[tmp] ~= nil then fn_seq(tmp, tbl[tmp]) tbl[tmp], tseq[tmp] = nil, marker elseif tbl[tmp] ~= nil then fn_oth(tmp, tbl[tmp]) tbl[tmp] = nil end end end if ctx.sorttype > 0 then local nums, words, nn, nw = get_sorted_key_list(tbl, natural_sort) if ctx.sorttype == 2 then for idx = 1, nw do fn_oth(words[idx], tbl[words[idx]]) end end for idx = 1, nn do if tseq[nums[idx]] ~= nil then fn_seq(nums[idx], tseq[nums[idx]]) else fn_oth(nums[idx], tbl[nums[idx]]) end end if ctx.sorttype ~= 2 then for idx = 1, nw do fn_oth(words[idx], tbl[words[idx]]) end end return end for key, val in ipairs(tseq) do if val ~= true then fn_seq(key, val) tbl[key] = nil end end for key, val in pairs(tbl) do fn_oth(key, val) end end -- Finalize and return a concatenated list local function finalize_and_return_concatenated_list (ctx, lst, len, modsize) if len > 0 then local tmp = ctx.oxfordsep or ctx.lastsep if tmp ~= nil and len > modsize * 2 then lst[len - modsize + 1] = tmp elseif len > modsize and ctx.lastsep ~= nil then lst[len - modsize + 1] = ctx.lastsep end lst[1] = ctx.header or '' if ctx.footer ~= nil then lst[len + 1] = ctx.footer end ctx.text = table.concat(lst) else ctx.text = ctx.ifngiven or '' end end --- --- --- PUBLIC ENVIRONMENT --- --- ________________________________ --- --- --- --[[ Modifiers ]]-- ------------------- -- Syntax: #invoke:params|sequential|pipe to library.sequential = function (ctx) if ctx.subset == 1 then error(modulename .. ': The ‘sequential’ directive has been provided more than once', 0) end if ctx.subset == -1 then error(modulename .. ': The two directives ‘non-sequential’ and ‘sequential’ are in contradiction with each other', 0) end if ctx.sorttype > 0 then error(modulename .. ': The ‘all_sorted’ and ‘reassorted’ directives are redundant when followed by ‘sequential’', 0) end ctx.iterfunc, ctx.subset = ipairs, 1 return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|non-sequential|pipe to library['non-sequential'] = function (ctx) if ctx.subset == -1 then error(modulename .. ': The ‘non-sequential’ directive has been provided more than once', 0) end if ctx.subset == 1 then error(modulename .. ': The two directives ‘sequential’ and ‘non-sequential’ are in contradiction with each other', 0) end ctx.iterfunc, ctx.subset = pairs, -1 return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|all_sorted|pipe to library.all_sorted = function (ctx) if ctx.sorttype == 1 then error(modulename .. ': The ‘all_sorted’ directive has been provided more than once', 0) end if ctx.subset == 1 then error(modulename .. ': The ‘all_sorted’ directive is redundant after ‘sequential’', 0) end if ctx.sorttype == 2 then error(modulename .. ': The two directives ‘reassorted’ and ‘sequential’ are in contradiction with each other', 0) end ctx.sorttype = 1 return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|reassorted|pipe to library.reassorted = function (ctx) if ctx.sorttype == 2 then error(modulename .. ': The ‘reassorted’ directive has been provided more than once', 0) end if ctx.subset == 1 then error(modulename .. ': The ‘reassorted’ directive is redundant after ‘sequential’', 0) end if ctx.sorttype == 1 then error(modulename .. ': The two directives ‘sequential’ and ‘reassorted’ are in contradiction with each other', 0) end ctx.sorttype = 2 return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|pinned_until|sentinel|[parameter name 1]|[parameter -- name 2]|...|parameter name N|sentinel|pipe to library.pinned_until = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘pinned_until’: No sentinel was provided', 0) end local tmp, bucket, curr, ncurr local sntl, idx = opts[offs + 1]:match'^%s*(.-)%s*$', 2 if ctx.pin_bucket == nil then bucket, curr, ncurr = {}, {}, 0 ctx.pin_bucket, ctx.pins = bucket, curr else bucket, curr, ncurr = ctx.pin_bucket, ctx.pins, ctx.npins end while opts[offs + idx] ~= nil do tmp = opts[offs + idx]:match'^%s*(.-)%s*$' if tmp == sntl then if idx == 2 then error(modulename .. ', ‘pinned_until’: No parameters to pin were provided', 0) end ctx.npins = ncurr + idx - 2 return context_iterate(ctx, offs + idx + 1) end if tmp == '0' or tmp:find'^%-?[1-9]%d*$' ~= nil then tmp = tonumber(tmp) end if bucket[tmp] then error(modulename .. ', ‘pinned_until’: Duplicate pinned parameter ‘' .. tostring(tmp) .. '’', 0) end curr[ncurr + idx - 1], bucket[tmp], idx = tmp, true, idx + 1 end error(modulename .. ', ‘pinned_until’: Missing sentinel in position #' .. tostring(idx), 0) end -- Syntax: #invoke:params|setting|directives|...|pipe to library.setting = function (ctx) local new_offs = set_strings_from_opts(ctx, ctx.pipe, ctx.fnpos + 1) if new_offs - ctx.fnpos < 2 then error(modulename .. ', ‘setting’: No directive was given', 0) end return context_iterate(ctx, new_offs + 1) end -- Syntax: #invoke:params|scoring|new parameter name|[container]|pipe to library.scoring = function (ctx) local opts, offs, retval = ctx.pipe, ctx.fnpos, 0 if opts[offs + 1] == nil then error(modulename .. ', ‘scoring’: No parameter name was provided', 0) end for _ in pairs(ctx.params) do retval = retval + 1 end local tn = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if tn == 'in_substack' then new_substack(ctx)[get_param_name(opts[offs + 1])] = tostring(retval) return context_iterate(ctx, offs + 3) end ctx.params[get_param_name(opts[offs + 1])] = tostring(retval) return tn == 'here' and context_iterate(ctx, offs + 3) or context_iterate(ctx, offs + 2, tn) end -- Syntax: #invoke:params|squeezing|pipe to library.squeezing = function (ctx) local store, indices, tbl, newlen = {}, {}, ctx.params, 0 for key, val in pairs(tbl) do if type(key) == 'number' then newlen = newlen + 1 indices[newlen], store[key], tbl[key] = key, val, nil end end table.sort(indices) for idx = 1, newlen do tbl[idx] = store[indices[idx]] end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|filling_the_gaps|pipe to library.filling_the_gaps = function (ctx) local newval, tbl, tmp, nmin, nmax, nnums = ctx.pipe[ctx.fnpos + 1], ctx.params, {}, 1, nil, -1 if newval == nil then error(modulename .. ', ‘filling_the_gaps’: No value was provided', 0) end for key, val in pairs(tbl) do if type(key) == 'number' then if nmax == nil then if key < nmin then nmin = key end nmax = key elseif key > nmax then nmax = key elseif key < nmin then nmin = key end tmp[key], nnums = val, nnums + 1 end end if nmax ~= nil and nmax - nmin > nnums then ctx.n_available = ctx.n_available + nmin + nnums - nmax if ctx.n_available < 0 then error(modulename .. ', ‘filling_the_gaps’: It is possible to fill at most ' .. tostring(maxfill) .. ' parameters', 0) end for idx = nmin, nmax do tbl[idx] = newval end for key, val in pairs(tmp) do tbl[key] = val end end return context_iterate(ctx, ctx.fnpos + 2) end -- Syntax: #invoke:params|clearing|pipe to library.clearing = function (ctx) local tbl, numerics = ctx.params, {} for key, val in pairs(tbl) do if type(key) == 'number' then numerics[key], tbl[key] = val, nil end end for key, val in ipairs(numerics) do tbl[key] = val end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|cutting|left cut|right cut|pipe to library.cutting = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local lcut = tonumber(opts[offs + 1]) if lcut == nil or math.floor(lcut) ~= lcut then error(modulename .. ', ‘cutting’: Left cut must be an integer number', 0) end local rcut = tonumber(opts[offs + 2]) if rcut == nil or math.floor(rcut) ~= rcut then error(modulename .. ', ‘cutting’: Right cut must be an integer number', 0) end local tbl = ctx.params local len = #tbl if lcut < 0 then lcut = len + lcut end if rcut < 0 then rcut = len + rcut end local tot = lcut + rcut if tot > 0 then local cache = {} if tot >= len then for key in ipairs(tbl) do tbl[key] = nil end tot = len else for idx = len - rcut + 1, len do tbl[idx] = nil end for idx = 1, lcut do tbl[idx] = nil end end for key, val in pairs(tbl) do if type(key) == 'number' and key > 0 then if key > len then cache[key - tot] = val else cache[key - lcut] = val end tbl[key] = nil end end for key, val in pairs(cache) do tbl[key] = val end end return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|cropping|left crop|right crop|pipe to library.cropping = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local lcut = tonumber(opts[offs + 1]) if lcut == nil or math.floor(lcut) ~= lcut then error(modulename .. ', ‘cropping’: Left crop must be an integer number', 0) end local rcut = tonumber(opts[offs + 2]) if rcut == nil or math.floor(rcut) ~= rcut then error(modulename .. ', ‘cropping’: Right crop must be an integer number', 0) end local tbl = ctx.params local nmin, nmax for key in pairs(tbl) do if type(key) == 'number' then if nmin == nil then nmin, nmax = key, key elseif key > nmax then nmax = key elseif key < nmin then nmin = key end end end if nmin ~= nil then local len = nmax - nmin + 1 if lcut < 0 then lcut = len + lcut end if rcut < 0 then rcut = len + rcut end if lcut + rcut - len > -1 then for key in pairs(tbl) do if type(key) == 'number' then tbl[key] = nil end end elseif lcut + rcut > 0 then for idx = nmax - rcut + 1, nmax do tbl[idx] = nil end for idx = nmin, nmin + lcut - 1 do tbl[idx] = nil end local lshift = nmin + lcut - 1 if lshift > 0 then for idx = lshift + 1, nmax do tbl[idx - lshift], tbl[idx] = tbl[idx], nil end end end end return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|purging|start offset|length|pipe to library.purging = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local idx = tonumber(opts[offs + 1]) if idx == nil or math.floor(idx) ~= idx then error(modulename .. ', ‘purging’: Start offset must be an integer number', 0) end local len = tonumber(opts[offs + 2]) if len == nil or math.floor(len) ~= len then error(modulename .. ', ‘purging’: Length must be an integer number', 0) end local tbl = ctx.params if len < 1 then len = len + table.maxn(tbl) if idx > len then return context_iterate(ctx, offs + 3) end len = len - idx + 1 end ctx.params = copy_table_reduced(tbl, idx, len) return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|backpurging|start offset|length|pipe to library.backpurging = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local last = tonumber(opts[offs + 1]) if last == nil or math.floor(last) ~= last then error(modulename .. ', ‘backpurging’: Start offset must be an integer number', 0) end local len = tonumber(opts[offs + 2]) if len == nil or math.floor(len) ~= len then error(modulename .. ', ‘backpurging’: Length must be an integer number', 0) end local idx local tbl = ctx.params if len > 0 then idx = last - len + 1 else for key in pairs(tbl) do if type(key) == 'number' and (idx == nil or key < idx) then idx = key end end if idx == nil then return context_iterate(ctx, offs + 3) end idx = idx - len if last < idx then return context_iterate(ctx, offs + 3) end len = last - idx + 1 end ctx.params = copy_table_reduced(ctx.params, idx, len) return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|shifting|addend|pipe to library.shifting = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local nshift = tonumber(ctx.pipe[ctx.fnpos + 1]) if nshift == nil or nshift == 0 or math.floor(nshift) ~= nshift then error(modulename .. ', ‘shifting’: A non-zero integer number must be provided', 0) end local tbl = {} for key, val in pairs(ctx.params) do if type(key) == 'number' then tbl[key + nshift] = val else tbl[key] = val end end ctx.params = tbl return context_iterate(ctx, ctx.fnpos + 2) end -- Syntax: #invoke:params|reversing_numeric_names|pipe to library.reversing_numeric_names = function (ctx) local tbl, numerics, nmax = ctx.params, {}, 0 for key, val in pairs(tbl) do if type(key) == 'number' then numerics[key], tbl[key] = val, nil if key > nmax then nmax = key end end end for key, val in pairs(numerics) do tbl[nmax - key + 1] = val end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|pivoting_numeric_names|pipe to --[[ library.pivoting_numeric_names = function (ctx) local tbl = ctx.params local shift = #tbl + 1 if shift < 2 then return library.reversing_numeric_names(ctx) end local tmp = {} for key, val in pairs(tbl) do if type(key) == 'number' then tmp[key], tbl[key] = val, nil end end for key, val in pairs(tmp) do tbl[shift - key] = val end return context_iterate(ctx, ctx.fnpos + 1) end ]]-- -- Syntax: #invoke:params|mirroring_numeric_names|pipe to --[[ library.mirroring_numeric_names = function (ctx) local nmax, nmin local tbl, tmp = ctx.params, {} for key, val in pairs(tbl) do if type(key) == 'number' then tmp[key], tbl[key] = val, nil if nmax == nil then nmin, nmax = key, key elseif key > nmax then nmax = key elseif key < nmin then nmin = key end end end for key, val in pairs(tmp) do tbl[nmax + nmin - key] = val end return context_iterate(ctx, ctx.fnpos + 1) end ]]-- -- Syntax: #invoke:params|swapping_numeric_names|pipe to --[[ library.swapping_numeric_names = function (ctx) local tmp local tbl, cache, nsize = ctx.params, {}, 1 for key in pairs(tbl) do if type(key) == 'number' then cache[nsize], nsize = key, nsize + 1 end end table.sort(cache) for idx = math.floor((nsize - 1) / 2), 1, -1 do tmp = tbl[cache[idx] ] tbl[cache[idx] ] = tbl[cache[nsize - idx] ] tbl[cache[nsize - idx] ] = tmp end return context_iterate(ctx, ctx.fnpos + 1) end ]]-- -- Syntax: #invoke:params|sorting_sequential_values|[criterion]|pipe to library.sorting_sequential_values = function (ctx) local sortfn local opts, offs = ctx.pipe, ctx.fnpos local tn = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tn ~= nil then sortfn = sortfunctions[tn] end if sortfn then table.sort(ctx.params, sortfn) else table.sort(ctx.params) end -- i.e. either `false` or `nil` if sortfn == nil then return context_iterate(ctx, offs + 1, tn) end return context_iterate(ctx, offs + 2) end -- Syntax: #invoke:params|splicing|[add to position]|position|increment| -- [number of elements to write]|...|pipe to library.splicing = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local tmp2, argc, pos, refp local tbl, opts, offs = ctx.params, ctx.pipe, ctx.fnpos local tmp1 = opts[offs + 1] if tmp1 ~= nil then tmp2 = tonumber(tmp1) if tmp2 == nil or math.floor(tmp2) ~= tmp2 then pos, argc, tmp2 = tonumber(opts[offs + 2]), offs + 4, tmp1:match'^%s*(.*%S)' if tmp2 ~= nil then refp = position_references[tmp2] if refp == nil then error(modulename .. ', ‘splicing’: ‘' .. tostring(tmp2) .. '’ is not a valid first argument', 0) end else refp = 0 end else pos, argc, refp = tmp2, offs + 3, 0 end else pos, argc, refp = tonumber(opts[offs + 2]), offs + 4, 0 end if pos == nil or math.floor(pos) ~= pos then error(modulename .. ', ‘splicing’: The position must be an integer number', 0) end local len = tonumber(opts[argc - 1]) if len == nil or math.floor(len) ~= len then error(modulename .. ', ‘splicing’: The increment must be an integer number', 0) end local insn = tonumber(opts[argc]) if len == 0 and (insn == nil or insn < 1) then error(modulename .. ', ‘splicing’: When the increment is zero the number of elements to write cannot be zero', 0) end if refp == 2 then for _ in ipairs(tbl) do pos = pos + 1 end refp = 0 end tmp1, tmp2 = nil, nil if refp ~= 0 or len ~= 0 then for key, val in pairs(tbl) do if type(key) == 'number' then if tmp1 == nil then tmp1, tmp2 = key, key elseif key < tmp1 then tmp1 = key elseif key > tmp2 then tmp2 = key end end end end if tmp2 == nil then len = 0 elseif refp == 3 then pos = pos + tmp2 elseif refp == 1 then pos = pos + tmp1 end if len > 0 and pos + len > tmp1 and pos <= tmp2 then tbl = copy_table_expanded(tbl, pos, len) elseif len < 0 and pos - len > tmp1 and pos <= tmp2 then tbl = copy_table_reduced(tbl, pos, -len) else tbl = copy_or_ref_table(tbl, tbl ~= ctx.oparams) end ctx.params = tbl if insn == nil or insn < 0 or math.floor(insn) ~= insn then return context_iterate(ctx, argc) end tmp1 = argc - offs - pos + 1 for key = pos, pos + insn - 1 do tbl[key] = opts[offs + key + tmp1] end return context_iterate(ctx, argc + insn + 1) end -- Syntax: #invoke:params|imposing|name|value|pipe to library.imposing = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘imposing’: Missing parameter name to impose', 0) end ctx.params[get_param_name(opts[offs + 1])] = opts[offs + 2] return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|providing|name|value|pipe to library.providing = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘providing’: Missing parameter name to provide', 0) end local key = get_param_name(opts[offs + 1]) if ctx.params[key] == nil then ctx.params[key] = opts[offs + 2] end return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|reassigning|source|destination|[mode]|pipe to library.reassigning = function (ctx) local tbl, opts, offs = ctx.params, ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘reassigning’: Missing source parameter', 0) end if opts[offs + 2] == nil then error(modulename .. ', ‘reassigning’: Missing destination parameter', 0) end local mode, argc local src, tn = get_param_name(opts[offs + 1]), opts[offs + 3] ~= nil and opts[offs + 3]:match'^%s*(.*%S)' local val = tbl[src] if tn ~= nil then mode = a_modes[tn] end if mode == nil then mode, argc = 0, offs + 3 else argc, tn = offs + 4, nil end if val == nil and mode > 1 then return context_iterate(ctx, argc, tn) end local dest = get_param_name(opts[offs + 2]) local tmp = tbl[dest] == nil if mode % 2 == 0 or (mode == 7 and tmp) then tbl[src] = nil end if tmp or mode < 4 then tbl[dest] = val end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|discarding|name|[how many]|pipe to library.discarding = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘discarding’: Missing parameter name to discard', 0) end local len = tonumber(opts[offs + 2]) if len == nil then ctx.params[get_param_name(opts[offs + 1])] = nil return context_iterate(ctx, offs + 2) end local key = tonumber(opts[offs + 1]) if key == nil or math.floor(key) ~= key then error(modulename .. ', ‘discarding’: A range was provided, but the initial parameter name is not an integer number', 0) end if len < 1 or math.floor(len) ~= len then error(modulename .. ', ‘discarding’: A range can only be an integer number greater than zero', 0) end for idx = key, key + len - 1 do ctx.params[idx] = nil end return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|excluding_non-numeric_names|pipe to library['excluding_non-numeric_names'] = function (ctx) local tmp = ctx.params for key, val in pairs(tmp) do if type(key) ~= 'number' then tmp[key] = nil end end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|excluding_numeric_names|pipe to library.excluding_numeric_names = function (ctx) local tmp = ctx.params for key, val in pairs(tmp) do if type(key) == 'number' then tmp[key] = nil end end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|with_name_matching|target 1|[plain flag 1]|[or]| -- [target 2]|[plain flag 2]|[or]|[...]|[target N]|[plain flag -- N]|pipe to library.with_name_matching = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local tmp, ptn local tbl, newparams, opts, offs = ctx.params, {}, ctx.pipe, ctx.fnpos local targets, nptns, argc, tn = load_pattern_args(opts, offs, 'with_name_matching') for idx = 1, nptns do ptn = targets[idx] if ptn[3] then tmp = ptn[1] if tmp == '0' or tmp:find'^%-?[1-9]%d*$' ~= nil then tmp = tonumber(tmp) end newparams[tmp] = tbl[tmp] else for key, val in pairs(tbl) do if tostring(key):find(ptn[1], 1, ptn[2]) then newparams[key] = val end end end end ctx.params = newparams return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|with_name_not_matching|target 1|[plain flag 1]| -- [and]|[target 2]|[plain flag 2]|[and]|[...]|[target N]|[plain -- flag N]|pipe to library.with_name_not_matching = function (ctx) local tbl, opts, offs = ctx.params, ctx.pipe, ctx.fnpos local targets, nptns, argc, tn = load_pattern_args(opts, offs, 'with_name_not_matching') if nptns == 1 and targets[1][3] then local tmp = targets[1][1] if tmp == '0' or tmp:find'^%-?[1-9]%d*$' ~= nil then tbl[tonumber(tmp)] = nil else tbl[tmp] = nil end return context_iterate(ctx, argc, tn) end local yesmatch, ptn for key in pairs(tbl) do yesmatch = true for idx = 1, nptns do ptn = targets[idx] if ptn[3] then if tostring(key) ~= ptn[1] then yesmatch = false break end elseif not tostring(key):find(ptn[1], 1, ptn[2]) then yesmatch = false break end end if yesmatch then tbl[key] = nil end end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|with_value_matching|target 1|[plain flag 1]|[or]| -- [target 2]|[plain flag 2]|[or]|[...]|[target N]|[plain flag -- N]|pipe to library.with_value_matching = function (ctx) local nomatch, ptn local tbl, opts, offs = ctx.params, ctx.pipe, ctx.fnpos local targets, nptns, argc, tn = load_pattern_args(opts, offs, 'with_value_matching') for key, val in pairs(tbl) do nomatch = true for idx = 1, nptns do ptn = targets[idx] if ptn[3] then if val == ptn[1] then nomatch = false break end elseif val:find(ptn[1], 1, ptn[2]) then nomatch = false break end end if nomatch then tbl[key] = nil end end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|with_value_not_matching|target 1|[plain flag 1]| -- [and]|[target 2]|[plain flag 2]|[and]|[...]|[target N]|[plain -- flag N]|pipe to library.with_value_not_matching = function (ctx) local yesmatch, ptn local tbl, opts, offs = ctx.params, ctx.pipe, ctx.fnpos local targets, nptns, argc, tn = load_pattern_args(opts, offs, 'with_value_not_matching') for key, val in pairs(tbl) do yesmatch = true for idx = 1, nptns do ptn = targets[idx] if ptn[3] then if val ~= ptn[1] then yesmatch = false break end elseif not val:find(ptn[1], 1, ptn[2]) then yesmatch = false break end end if yesmatch then tbl[key] = nil end end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|keeping_at_most|number of parameters to pick|pipe to library.keeping_at_most = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local len = tonumber(ctx.pipe[ctx.fnpos + 1]) if len == nil or len < 1 or math.floor(len) ~= len then error(modulename .. ', ‘keeping_at_most’: The number of parameters to keep must be an integer greater than zero', 0) end ctx.params = copy_table_maxn({}, ctx.params, len) return context_iterate(ctx, ctx.fnpos + 2) end -- Syntax: #invoke:params|trimming_values|pipe to library.trimming_values = function (ctx) local tbl = ctx.params for key, val in pairs(tbl) do tbl[key] = val:match'^%s*(.-)%s*$' end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|mapping_to_lowercase|pipe to library.mapping_to_lowercase = function (ctx) local tbl = ctx.params for key, val in pairs(tbl) do tbl[key] = val:lower() end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|mapping_to_uppercase|pipe to library.mapping_to_uppercase = function (ctx) local tbl = ctx.params for key, val in pairs(tbl) do tbl[key] = val:upper() end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|mapping_by_calling|template name|[call -- style]|[let/use]|[...]|[let/use]|[...]|[number of additional -- parameters]|[parameter 1]|[parameter 2]|[...]|[parameter N]|pipe to library.mapping_by_calling = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local tname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tname == nil then error(modulename .. ', ‘mapping_by_calling’: No template name was provided', 0) end local margs, argc, looptype, karg, varg, tbl, mem = load_callback_opts(opts, offs + 1, mapping_styles.values_only, ctx.params) local model = { title = tname, args = margs } value_maps[looptype](tbl, margs, karg, varg, function () return ctx.frame:expandTemplate(model) end) for key, val in pairs(mem) do tbl[key] = val end ctx.params = tbl return context_iterate(ctx, argc) end -- Syntax: #invoke:params|mapping_by_invoking|module name|function name|[call -- style]|[let/use]|[...]|[let/use]|[...]|[number of additional -- arguments]|[argument 1]|[argument 2]|[...]|[argument N]|pipe to library.mapping_by_invoking = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local mname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if mname == nil then error(modulename .. ', ‘mapping_by_invoking’: No module name was provided', 0) end local fname = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ', ‘mapping_by_invoking’: No function name was provided', 0) end local margs, argc, looptype, karg, varg, tbl, mem = load_callback_opts(opts, offs + 2, mapping_styles.values_only, ctx.params) local model = { title = 'Module:' .. mname, args = margs } local mfunc = require(model.title)[fname] if mfunc == nil then error(modulename .. ', ‘mapping_by_invoking’: The function ‘' .. fname .. '’ does not exist', 0) end value_maps[looptype](tbl, margs, karg, varg, function () return tostring(mfunc(ctx.frame:newChild(model))) end) for key, val in pairs(mem) do tbl[key] = val end ctx.params = tbl return context_iterate(ctx, argc) end -- Syntax: #invoke:params|mapping_by_magic|parser function|[call -- style]|[let/use]|[...]|[let/use]|[...]|[number of additional -- arguments]|[argument 1]|[argument 2]|[...]|[argument N]|pipe to library.mapping_by_magic = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local magic = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if magic == nil then error(modulename .. ', ‘mapping_by_magic’: No parser function was provided', 0) end local margs, argc, looptype, karg, varg, tbl, mem = load_callback_opts(opts, offs + 1, mapping_styles.values_only, ctx.params) value_maps[looptype](tbl, margs, karg, varg, function () return ctx.frame:callParserFunction(magic, margs) end) for key, val in pairs(mem) do tbl[key] = val end ctx.params = tbl return context_iterate(ctx, argc) end -- Syntax: #invoke:params|mapping_by_replacing|target|replace|[count]|[plain -- flag]|pipe to library.mapping_by_replacing = function (ctx) local ptn, repl, nmax, flg, argc, die, tn = load_replace_args(ctx.pipe, ctx.fnpos, 'mapping_by_replacing') if die then return context_iterate(ctx, argc, tn) end local tbl = ctx.params if flg == 3 then for key, val in pairs(tbl) do if val == ptn then tbl[key] = repl end end else if flg == 2 then -- Copied from Module:String's `str._escapePattern()` ptn = ptn:gsub('[%(%)%.%%%+%-%*%?%[%^%$%]]', '%%%0') end for key, val in pairs(tbl) do tbl[key] = val:gsub(ptn, repl, nmax) end end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|mapping_by_mixing|mixing string|pipe to library.mapping_by_mixing = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘mapping_by_mixing’: No mixing string was provided', 0) end local tbl, mix = ctx.params, opts[offs + 1] if mix == '$#' then for key in pairs(tbl) do tbl[key] = tostring(key) end return context_iterate(ctx, offs + 2) end local skel, cnv, n_parts = parse_placeholder_string(mix) for key, val in pairs(tbl) do for idx = 2, n_parts, 2 do if skel[idx] then cnv[idx] = val else cnv[idx] = tostring(key) end end tbl[key] = table.concat(cnv) end return context_iterate(ctx, offs + 2) end -- Syntax: #invoke:params|renaming_to_lowercase|pipe to library.renaming_to_lowercase = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local cache = {} for key, val in pairs(ctx.params) do if type(key) == 'string' then cache[key:lower()] = val else cache[key] = val end end ctx.params = cache return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|renaming_to_uppercase|pipe to library.renaming_to_uppercase = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local cache = {} for key, val in pairs(ctx.params) do if type(key) == 'string' then cache[key:upper()] = val else cache[key] = val end end ctx.params = cache return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|renaming_to_sequence|[sort order]|pipe to library.renaming_to_sequence = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local cache, len local tbl = ctx.params local sortfn, argc, dosort, tn = load_sort_opt(ctx.pipe[ctx.fnpos + 1]) if dosort then local words, wl cache, words, len, wl = get_sorted_key_list(tbl, sortfn) for idx = 1, len do cache[idx] = tbl[cache[idx]] end for idx = 1, wl do cache[len + idx] = tbl[words[idx]] end else cache, len = {}, 1 for _, val in pairs(tbl) do cache[len], len = val, len + 1 end end ctx.params = cache return context_iterate(ctx, ctx.fnpos + argc, tn) end -- Syntax: #invoke:params|renaming_by_calling|template name|[call -- style]|[let/use]|[...]|[let/use]|[...]|[number of additional -- parameters]|[parameter 1]|[parameter 2]|[...]|[parameter N]|pipe to library.renaming_by_calling = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local tname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tname == nil then error(modulename .. ', ‘renaming_by_calling’: No template name was provided', 0) end local rargs, argc, looptype, karg, varg, tbl, mem = load_callback_opts(opts, offs + 1, mapping_styles.names_only, ctx.params) local model = { title = tname, args = rargs } map_names(tbl, rargs, karg, varg, looptype, function () return ctx.frame:expandTemplate(model) end) for key, val in pairs(mem) do tbl[key] = val end ctx.params = tbl return context_iterate(ctx, argc) end -- Syntax: #invoke:params|renaming_by_invoking|module name|function -- name|[call style]|[let/use]|[...]|[let/use]|[...]|[number of -- additional arguments]|[argument 1]|[argument 2]|[...]|[argument -- N]|pipe to library.renaming_by_invoking = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local mname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if mname == nil then error(modulename .. ', ‘renaming_by_invoking’: No module name was provided', 0) end local fname = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ', ‘renaming_by_invoking’: No function name was provided', 0) end local rargs, argc, looptype, karg, varg, tbl, mem = load_callback_opts(opts, offs + 2, mapping_styles.names_only, ctx.params) local model = { title = 'Module:' .. mname, args = rargs } local mfunc = require(model.title)[fname] if mfunc == nil then error(modulename .. ', ‘renaming_by_invoking’: The function ‘' .. fname .. '’ does not exist', 0) end map_names(tbl, rargs, karg, varg, looptype, function () return tostring(mfunc(ctx.frame:newChild(model))) end) for key, val in pairs(mem) do tbl[key] = val end ctx.params = tbl return context_iterate(ctx, argc) end -- Syntax: #invoke:params|renaming_by_magic|parser function|[call -- style]|[let/use]|[...]|[let/use]|[...]|[number of additional -- arguments]|[argument 1]|[argument 2]|[...]|[argument N]|pipe to library.renaming_by_magic = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local magic = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if magic == nil then error(modulename .. ', ‘renaming_by_magic’: No parser function was provided', 0) end local rargs, argc, looptype, karg, varg, tbl, mem = load_callback_opts(opts, offs + 1, mapping_styles.names_only, ctx.params) map_names(tbl, rargs, karg, varg, looptype, function () return ctx.frame:callParserFunction(magic, rargs) end) for key, val in pairs(mem) do tbl[key] = val end ctx.params = tbl return context_iterate(ctx, argc) end -- Syntax: #invoke:params|renaming_by_replacing|target|replace|[count]|[plain -- flag]|pipe to library.renaming_by_replacing = function (ctx) local ptn, repl, nmax, flg, argc, die, tn = load_replace_args(ctx.pipe, ctx.fnpos, 'renaming_by_replacing') if die then return context_iterate(ctx, argc, tn) end local tbl = ctx.params if flg == 3 then ptn = get_param_name(ptn) local val = tbl[ptn] if val ~= nil then tbl[ptn], tbl[get_param_name(repl)] = nil, val end else if flg == 2 then -- Copied from Module:String's `str._escapePattern()` ptn = ptn:gsub('[%(%)%.%%%+%-%*%?%[%^%$%]]', '%%%0') end local cache = {} for key, val in pairs(tbl) do steal_if_renamed(val, tbl, key, cache, tostring(key):gsub(ptn, repl, nmax)) end for key, val in pairs(cache) do tbl[key] = val end end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|renaming_by_mixing|mixing string|pipe to library.renaming_by_mixing = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local mix = ctx.pipe[ctx.fnpos + 1] if mix == nil then error(modulename .. ', ‘renaming_by_mixing’: No mixing string was provided', 0) end local cache = {} mix = mix:match'^%s*(.-)%s*$' if mix == '$@' then for _, val in pairs(ctx.params) do cache[get_param_name(val)] = val end else local skel, canvas, n_parts = parse_placeholder_string(mix) for key, val in pairs(ctx.params) do for idx = 2, n_parts, 2 do if skel[idx] then canvas[idx] = val else canvas[idx] = tostring(key) end end cache[get_param_name(table.concat(canvas))] = val end end ctx.params = cache return context_iterate(ctx, ctx.fnpos + 2) end -- Syntax: #invoke:params|grouping_by_calling|template -- name|[let/use]|[...]|[let/use]|[...]|[number of additional -- arguments]|[argument 1]|[argument 2]|[...]|[argument N]|pipe to library.grouping_by_calling = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local opts, offs = ctx.pipe, ctx.fnpos local tmp, argc, tbl, mem = load_child_opts(opts, offs + 2, 0, ctx.params) local gargs = {} for key, val in pairs(tmp) do if type(key) == 'number' and key < 1 then gargs[key - 1] = val else gargs[key] = val end end tmp = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tmp == nil then error(modulename .. ', ‘grouping_by_calling’: No template name was provided', 0) end local model = { title = tmp } local groups = make_groups(tbl) for gid, group in pairs(groups) do for key, val in pairs(gargs) do group[key] = val end group[0], model.args = gid, group groups[gid] = ctx.frame:expandTemplate(model) end for key, val in pairs(mem) do groups[key] = val end ctx.params = groups return context_iterate(ctx, argc) end -- Syntax: #invoke:params|parsing|string to parse|[trim flag]|[iteration -- delimiter setter]|[...]|[key-value delimiter setter]|[...]|pipe to library.parsing = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘parsing’: No string to parse was provided', 0) end local isep, iplain, psep, pplain, trimnamed, trimunnamed, argc, tn = load_parse_opts(opts, offs + 2, '|', '=') parse_parameter_string(ctx.params, opts[offs + 1], isep, iplain, psep, pplain, trimnamed, trimunnamed) return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|reinterpreting|parameter to reinterpret|[trim -- flag]|[iteration delimiter setter]|[...]|[key-value delimiter -- setter]|[...]|pipe to library.reinterpreting = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘reinterpreting’: No parameter to reinterpret was provided', 0) end local isep, iplain, psep, pplain, trimnamed, trimunnamed, argc, tn = load_parse_opts(opts, offs + 2, '|', '=') local tbl, tmp = ctx.params, get_param_name(opts[offs + 1]) local str = tbl[tmp] if str ~= nil then tbl[tmp] = nil parse_parameter_string(tbl, str, isep, iplain, psep, pplain, trimnamed, trimunnamed) end return context_iterate(ctx, argc, tn) end -- Syntax: #invoke:params|evaluating|string to parse|[trim flag]|[iteration -- delimiter setter]|[...]|[key-value delimiter setter]|[...]|pipe to library.evaluating = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘evaluating’: No string to parse was provided', 0) end local isep, iplain, psep, pplain, trimnamed, trimunnamed, repos, tn = load_parse_opts(opts, offs + 2, '!', ':') if opts[offs + 1]:match'^%s*(.*%S)' == nil then remove_numeric_keys(opts, offs, repos - offs) return context_iterate(ctx, offs, tn) end local new_opts, cache = {}, {} parse_parameter_string(cache, opts[offs + 1], isep, iplain, psep, pplain, trimnamed, trimunnamed) local shift = #cache + offs - repos + 1 for key, val in pairs(opts) do if type(key) ~= 'number' or key < offs then new_opts[key] = val elseif key >= repos then new_opts[key + shift] = val end end for key, val in pairs(cache) do if type(key) ~= 'number' or key < 1 then new_opts[key] = val else new_opts[key + offs] = val end end ctx.pipe = new_opts return context_iterate(ctx, offs + 1) end -- Syntax: #invoke:params|mixing_names_and_values|mixing string|pipe to library.mixing_names_and_values = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘mixing_names_and_values’: No mixing string was provided for parameter names', 0) end if opts[offs + 2] == nil then error(modulename .. ', ‘mixing_names_and_values’: No mixing string was provided for parameter values', 0) end local tmp local cache, mix_k, mix_v = {}, opts[offs + 1]:match'^%s*(.-)%s*$', opts[offs + 2] if mix_k == '$@' and mix_v == '$@' then for _, val in pairs(ctx.params) do cache[get_param_name(val)] = val end elseif mix_k == '$@' and mix_v == '$#' then for key, val in pairs(ctx.params) do cache[get_param_name(val)] = tostring(key) end elseif mix_k == '$#' and mix_v == '$#' then for key in pairs(ctx.params) do cache[key] = tostring(key) end else local skel_k, cnv_k, n_parts_k = parse_placeholder_string(mix_k) local skel_v, cnv_v, n_parts_v = parse_placeholder_string(mix_v) for key, val in pairs(ctx.params) do tmp = tostring(key) for idx = 2, n_parts_k, 2 do if skel_k[idx] then cnv_k[idx] = val else cnv_k[idx] = tmp end end for idx = 2, n_parts_v, 2 do if skel_v[idx] then cnv_v[idx] = val else cnv_v[idx] = tmp end end cache[get_param_name(table.concat(cnv_k))] = table.concat(cnv_v) end end ctx.params = cache return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|combining|new parameter name|[sort -- order]|[with/without flushed glue]|setting directives|...|pipe to library.combining = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning return context_iterate(ctx, combine_parameters( ctx, function (key, val, kvs) return key .. kvs .. val end, 'combining' )) end -- Syntax: #invoke:params|combining_values|new parameter name|[sort -- order]|[with/without flushed glue]|setting directives|...|pipe to library.combining_values = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning return context_iterate(ctx, combine_parameters( ctx, function (key, val, kvs) return val end, 'combining_values' )) end -- Syntax: #invoke:params|combining_by_calling|template name|new parameter -- name|pipe to library.combining_by_calling = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local opts, offs = ctx.pipe, ctx.fnpos local tname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tname == nil then error(modulename .. ', ‘combining_by_calling’: No template name was provided', 0) end if opts[offs + 2] == nil then error(modulename .. ', ‘combining_by_calling’: No parameter name was provided', 0) end ctx.params = { [get_param_name(opts[offs + 2])] = ctx.frame:expandTemplate{ title = tname, args = ctx.params } } return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|combining_by_invoking|module name|function name|new -- parameter name|pipe to library.combining_by_invoking = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local opts, offs = ctx.pipe, ctx.fnpos local mname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if mname == nil then error(modulename .. ', ‘combining_by_invoking’: No module name was provided', 0) end local fname = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ', ‘combining_by_invoking’: No function name was provided', 0) end if opts[offs + 3] == nil then error(modulename .. ', ‘combining_by_invoking’: No parameter name was provided', 0) end local model = { title = 'Module:' .. mname, args = ctx.params } local mfunc = require(model.title)[fname] if mfunc == nil then error(modulename .. ', ‘mapping_by_invoking’: The function ‘' .. fname .. '’ does not exist', 0) end ctx.params = { [get_param_name(opts[offs + 3])] = tostring(mfunc(ctx.frame:newChild(model))) } return context_iterate(ctx, offs + 4) end -- Syntax: #invoke:params|combining_by_magic|parser function|new parameter -- name|pipe to library.combining_by_magic = function (ctx) -- NOTE: `ctx.params` might be the original metatable! As a modifier, -- this function MUST create a copy of it before returning local opts, offs = ctx.pipe, ctx.fnpos local magic = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if magic == nil then error(modulename .. ', ‘combining_by_magic’: No parser function was provided', 0) end if opts[offs + 2] == nil then error(modulename .. ', ‘combining_by_magic’: No parameter name was provided', 0) end ctx.params = { [get_param_name(opts[offs + 2])] = ctx.frame:callParserFunction(magic, ctx.params) } return context_iterate(ctx, offs + 3) end -- Syntax: #invoke:params|snapshotting|[maximum number]|pipe to library.snapshotting = function (ctx) return context_iterate(ctx, ctx.fnpos + make_child(ctx, ctx.params, 'snapshotting')) end -- Syntax: #invoke:params|remembering|[maximum number]|pipe to library.remembering = function (ctx) return context_iterate(ctx, ctx.fnpos + make_child(ctx, ctx.oparams, 'remembering')) end -- Syntax: #invoke:params|entering_substack|[new]|pipe to library.entering_substack = function (ctx) local tbl, opts, offs, ncurrparent = ctx.params, ctx.pipe, ctx.fnpos, ctx.n_parents + 1 local tn = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if ctx.parents == nil then ctx.parents = { tbl } else ctx.parents[ncurrparent] = tbl end ctx.n_parents = ncurrparent if tn == 'new' then ctx.params = {} return context_iterate(ctx, offs + 2) end local currsnap = ctx.n_children if currsnap > 0 then ctx.params, ctx.children[currsnap], ctx.n_children = ctx.children[currsnap], nil, currsnap - 1 else local newparams = {} for key, val in pairs(tbl) do newparams[key] = val end ctx.params = newparams end return context_iterate(ctx, offs + 1, tn) end -- Syntax: #invoke:params|pulling|parameter name|pipe to library.pulling = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘pulling’: No parameter to pull was provided', 0) end local tmp = ctx.n_parents local parent = tmp < 1 and ctx.oparams or ctx.parents[tmp] tmp = get_param_name(opts[offs + 1]) if parent[tmp] ~= nil then ctx.params[tmp] = parent[tmp] end return context_iterate(ctx, ctx.fnpos + 2) end -- Syntax: #invoke:params|recalling|parameter name|pipe to library.recalling = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘recalling’: No parameter to recall was provided', 0) end local arg = get_param_name(opts[offs + 1]) if ctx.oparams[arg] ~= nil then ctx.params[arg] = ctx.oparams[arg] end return context_iterate(ctx, ctx.fnpos + 2) end -- Syntax: #invoke:params|finding|parameter name|pipe to --[[ library.finding = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘finding’: No parameter to find was provided', 0) end local arg = get_param_name(opts[offs + 1]) local parent for idx = ctx.n_parents, 1, -1 do parent = ctx.parents[idx] if parent[arg] ~= nil then ctx.params[arg] = parent[arg] return context_iterate(ctx, offs + 2) end end if ctx.oparams[arg] ~= nil then ctx.params[arg] = ctx.oparams[arg] end return context_iterate(ctx, offs + 2) end ]]-- -- Syntax: #invoke:params|picking|number of parameters to pick|pipe to --[[ library.picking = function (ctx) local len = tonumber(ctx.pipe[ctx.fnpos + 1]) if len == nil or len < 1 or math.floor(len) ~= len then error(modulename .. ', ‘picking’: The number of parameters to pick must be an integer greater than zero', 0) end if ctx.n_parents < 1 then copy_table_maxn(ctx.params, ctx.oparams, len) else copy_table_maxn(ctx.params, ctx.parents[ctx.n_parents], len) end return context_iterate(ctx, ctx.fnpos + 2) end ]]-- -- Syntax: #invoke:params|detaching_substack|pipe to library.detaching_substack = function (ctx) local ncurrparent = ctx.n_parents if ncurrparent < 1 then error(modulename .. ', ‘detaching_substack’: No substacks have been created', 0) end local parent = ctx.parents[ncurrparent] for key in pairs(ctx.params) do parent[key] = nil end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|dropping_substack|pipe to library.dropping_substack = function (ctx) local ncurrparent = ctx.n_parents if ncurrparent < 1 then error(modulename .. ', ‘dropping_substack’: No substacks have been created', 0) end ctx.params, ctx.parents[ncurrparent], ctx.n_parents = ctx.parents[ncurrparent], nil, ncurrparent - 1 return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|leaving_substack|pipe to library.leaving_substack = function (ctx) local ncurrparent = ctx.n_parents if ncurrparent < 1 then error(modulename .. ', ‘leaving_substack’: No substacks have been created', 0) end local currsnap = ctx.n_children + 1 if ctx.children == nil then ctx.children = { ctx.params } else ctx.children[currsnap] = ctx.params end ctx.params, ctx.parents[ncurrparent], ctx.n_parents, ctx.n_children = ctx.parents[ncurrparent], nil, ncurrparent - 1, currsnap return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|merging_substack|pipe to library.merging_substack = function (ctx) local ncurrparent = ctx.n_parents if ncurrparent < 1 then error(modulename .. ', ‘merging_substack’: No substack has been created', 0) end local parent, child = ctx.parents[ncurrparent], ctx.params ctx.params, ctx.parents[ncurrparent], ctx.n_parents = parent, nil, ncurrparent - 1 for key, val in pairs(child) do parent[key] = val end return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|rearranging_substacks|...|pipe to library.rearranging_substacks = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local tmp = tonumber(opts[offs + 1]) if tmp == nil then error(modulename .. ', ‘rearranging_substacks’: You must specify at least one substack', 0) end local argc local oldchdn, newchdn, ntot, sid = ctx.children, {}, ctx.n_children, 1 repeat if tmp > ntot or tmp < 1 or math.floor(tmp) ~= tmp then error(modulename .. ', ‘rearranging_substacks’: Substack #' .. tostring(tmp) .. ' does not exist', 0) end if oldchdn[ntot - tmp + 1] == nil then error(modulename .. ', ‘rearranging_substacks’: Substack #' .. tostring(tmp) .. ' appears multiple times', 0) end newchdn[ntot - sid + 1], oldchdn[ntot - tmp + 1], sid = oldchdn[ntot - tmp + 1], nil, sid + 1 tmp = tonumber(opts[offs + sid]) until tmp == nil ctx.children, argc, sid = newchdn, offs + sid, 1 for idx = 1, ntot do tmp = oldchdn[idx] if tmp ~= nil then newchdn[sid], sid = tmp, sid + 1 end end return context_iterate(ctx, argc) end -- Syntax: #invoke:params|flushing|pipe to library.flushing = function (ctx) if ctx.n_children < 1 then error(modulename .. ', ‘flushing’: There are no substacks to flush', 0) end local parent, currsnap = ctx.params, ctx.n_children for key, val in pairs(ctx.children[currsnap]) do parent[key] = val end ctx.children[currsnap], ctx.n_children = nil, currsnap - 1 return context_iterate(ctx, ctx.fnpos + 1) end -- Syntax: #invoke:params|setting_by_flushing|pipe to library.setting_by_flushing = function (ctx) set_strings_from_substack(ctx, ctx, 'setting_by_flushing') return context_iterate(ctx, ctx.fnpos + 1) end --[[ Functions ]]-- ----------------------------- -- Syntax: #invoke:params|count library.count = function (ctx) -- NOTE: `ctx.params` might be the original metatable! local retval = 0 for _ in ctx.iterfunc(ctx.params) do retval = retval + 1 end if ctx.subset == -1 then retval = retval - #ctx.params end ctx.text = retval return false end -- Syntax: #invoke:args|concat_and_call|template name|[prepend 1]|[prepend 2]| -- [...]|[item n]|[named item 1=value 1]|[...]|[named item n=value -- n]|[...] library.concat_and_call = function (ctx) -- NOTE: `ctx.params` might be the original metatable! local opts, offs = ctx.pipe, ctx.fnpos local tname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tname == nil then error(modulename .. ', ‘concat_and_call’: No template name was provided', 0) end ctx.text = ctx.frame:expandTemplate{ title = tname, args = concat_params(ctx, offs + 1) } return false end -- Syntax: #invoke:args|concat_and_invoke|module name|function name|[prepend -- 1]|[prepend 2]|[...]|[item n]|[named item 1=value 1]|[...]|[named -- item n=value n]|[...] library.concat_and_invoke = function (ctx) -- NOTE: `ctx.params` might be the original metatable! local opts, offs = ctx.pipe, ctx.fnpos local mname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if mname == nil then error(modulename .. ', ‘concat_and_invoke’: No module name was provided', 0) end local fname = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ', ‘concat_and_invoke’: No function name was provided', 0) end local mfunc = require('Module:' .. mname)[fname] if mfunc == nil then error(modulename .. ', ‘concat_and_invoke’: The function ‘' .. fname .. '’ does not exist', 0) end ctx.text = mfunc(ctx.frame:newChild{ title = 'Module:' .. mname, args = concat_params(ctx, offs + 2) }) return false end -- Syntax: #invoke:args|concat_and_magic|parser function|[prepend 1]|[prepend -- 2]|[...]|[item n]|[named item 1=value 1]|[...]|[named item n= -- value n]|[...] library.concat_and_magic = function (ctx) -- NOTE: `ctx.params` might be the original metatable! local opts, offs = ctx.pipe, ctx.fnpos local magic = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if magic == nil then error(modulename .. ', ‘concat_and_magic’: No parser function was provided', 0) end ctx.text = ctx.frame:callParserFunction(magic, concat_params(ctx, offs + 1)) return false end -- Syntax: #invoke:params|value_of|parameter name library.value_of = function (ctx) -- NOTE: `ctx.params` might be the original metatable! local opts, offs = ctx.pipe, ctx.fnpos if opts[offs + 1] == nil then error(modulename .. ', ‘value_of’: No parameter name was provided', 0) end local val local key = opts[offs + 1]:match'^%s*(.-)%s*$' if key == '0' or key:find'^%-?[1-9]%d*$' ~= nil then key = tonumber(key) val = ctx.params[key] -- No worries: #ctx.params is unused when the modifier is in -- first position (and therefore `ctx.params` is a metatable) if val ~= nil and ( ctx.subset ~= -1 or key > #ctx.params or key < 1 ) and ( ctx.subset ~= 1 or (key <= #ctx.params and key > 0) ) then ctx.text = (ctx.header or '') .. val .. (ctx.footer or '') else ctx.text = ctx.ifngiven or '' end else val = ctx.params[key] if ctx.subset ~= 1 and val ~= nil then ctx.text = (ctx.header or '') .. val .. (ctx.footer or '') else ctx.text = ctx.ifngiven or '' end end return false end -- Syntax: #invoke:params|list library.list = function (ctx) local ret, nss, kvs, pps = {}, 0, ctx.pairsep or '', ctx.itersep or '' flush_params(ctx, function (key, val) ret[nss + 1], ret[nss + 2], ret[nss + 3], ret[nss + 4], nss = pps, key, kvs, val, nss + 4 end) finalize_and_return_concatenated_list(ctx, ret, nss, 4) return false end -- Syntax: #invoke:params|list_values library.list_values = function (ctx) -- NOTE: `library.coins()` and `library.unique_coins()` rely on us local ret, nss, pps = {}, 0, ctx.itersep or '' flush_params(ctx, function (key, val) ret[nss + 1], ret[nss + 2], nss = pps, val, nss + 2 end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|list_maybe_with_names library.list_maybe_with_names = function (ctx) local ret, nss, kvs, pps = {}, 0, ctx.pairsep or '', ctx.itersep or '' mixed_flush_params( ctx, function (key, val) ret[nss + 1], ret[nss + 2], ret[nss + 3], ret[nss + 4], nss = pps, '', '', val, nss + 4 end, function (key, val) ret[nss + 1], ret[nss + 2], ret[nss + 3], ret[nss + 4], nss = pps, key, kvs, val, nss + 4 end ) finalize_and_return_concatenated_list(ctx, ret, nss, 4) return false end -- Syntax: #invoke:params|for_each|wikitext library.for_each = function (ctx) local ret, nss, pps, txt = {}, 0, ctx.itersep or '', ctx.pipe[ctx.fnpos + 1] or '' local skel, cnv, n_parts = parse_placeholder_string(txt) flush_params(ctx, function (key, val) for idx = 2, n_parts, 2 do if skel[idx] then cnv[idx] = val else cnv[idx] = tostring(key) end end ret[nss + 1], nss = pps, nss + 2 ret[nss] = table.concat(cnv) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|call_for_each|template name|[append 1]|[append 2]| -- [...]|[append n]|[named param 1=value 1]|[...]|[named param -- n=value n]|[...] library.call_for_each = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local tname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tname == nil then error(modulename .. ', ‘call_for_each’: No template name was provided', 0) end local cargs = copy_table_reduced(opts, 1, offs - 1) local model, ret, nss, ccs = { title = tname, args = cargs }, {}, 0, ctx.itersep or '' flush_params(ctx, function (key, val) cargs[1], cargs[2], ret[nss + 1], nss = key, val, ccs, nss + 2 ret[nss] = ctx.frame:expandTemplate(model) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|invoke_for_each|module name|module function|[append -- 1]|[append 2]|[...]|[append n]|[named param 1=value 1]|[...]| -- [named param n=value n]|[...] library.invoke_for_each = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local mname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if mname == nil then error(modulename .. ', ‘invoke_for_each’: No module name was provided', 0) end local fname = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ', ‘invoke_for_each’: No function name was provided', 0) end local iargs = copy_table_reduced(ctx.pipe, 1, offs) local model = { title = 'Module:' .. mname, args = iargs } local mfunc, ret, nss, ccs = require(model.title)[fname], {}, 0, ctx.itersep or '' if mfunc == nil then error(modulename .. ', ‘invoke_for_each’: The function ‘' .. fname .. '’ does not exist', 0) end flush_params(ctx, function (key, val) iargs[1], iargs[2], ret[nss + 1], nss = key, val, ccs, nss + 2 ret[nss] = mfunc(ctx.frame:newChild(model)) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|magic_for_each|parser function|[append 1]|[append -- 2]|[...]|[append n]|[named param 1=value 1]|[...]|[named param -- n=value n]|[...] library.magic_for_each = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local magic = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if magic == nil then error(modulename .. ', ‘magic_for_each’: No parser function was provided', 0) end local ret, nss, ccs, cargs = {}, 0, ctx.itersep or '', copy_table_reduced(opts, 1, offs - 1) flush_params(ctx, function (key, val) cargs[1], cargs[2], ret[nss + 1], nss = key, val, ccs, nss + 2 ret[nss] = ctx.frame:callParserFunction(magic, cargs) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|call_for_each_value|template name|[append 1]|[append -- 2]|[...]|[append n]|[named param 1=value 1]|[...]|[named param -- n=value n]|[...] library.call_for_each_value = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local tname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tname == nil then error(modulename .. ', ‘call_for_each_value’: No template name was provided', 0) end local cargs = copy_table_reduced(ctx.pipe, 1, offs) local model = { title = tname, args = cargs } local ret, nss, ccs = {}, 0, ctx.itersep or '' flush_params(ctx, function (key, val) cargs[1], ret[nss + 1], nss = val, ccs, nss + 2 ret[nss] = ctx.frame:expandTemplate(model) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|invoke_for_each_value|module name|[append 1]|[append -- 2]|[...]|[append n]|[named param 1=value 1]|[...]|[named param -- n=value n]|[...] library.invoke_for_each_value = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local mname = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if mname == nil then error(modulename .. ', ‘invoke_for_each_value’: No module name was provided', 0) end local fname = opts[offs + 2] and opts[offs + 2]:match'^%s*(.*%S)' if fname == nil then error(modulename .. ', ‘invoke_for_each_value’: No function name was provided', 0) end local iargs = copy_table_reduced(ctx.pipe, 1, offs + 1) local model = { title = 'Module:' .. mname, args = iargs } local mfunc, ret, nss, ccs = require(model.title)[fname], {}, 0, ctx.itersep or '' if mfunc == nil then error(modulename .. ', ‘invoke_for_each_value’: The function ‘' .. fname .. '’ does not exist', 0) end flush_params(ctx, function (key, val) iargs[1], ret[nss + 1], nss = val, ccs, nss + 2 ret[nss] = mfunc(ctx.frame:newChild(model)) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|magic_for_each_value|parser function|[append 1]| -- [append 2]|[...]|[append n]|[named param 1=value 1]|[...]|[named -- param n=value n]|[...] library.magic_for_each_value = function (ctx) local opts, offs = ctx.pipe, ctx.fnpos local magic = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if magic == nil then error(modulename .. ', ‘magic_for_each_value’: No parser function was provided', 0) end local cargs, ret, nss, ccs = copy_table_reduced(opts, 1, offs), {}, 0, ctx.itersep or '' flush_params(ctx, function (key, val) cargs[1], ret[nss + 1], nss = val, ccs, nss + 2 ret[nss] = ctx.frame:callParserFunction(magic, cargs) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end -- Syntax: #invoke:params|call_for_each_group|template name|[append 1]|[append -- 2]|[...]|[append n]|[named param 1=value 1]|[...]|[named param -- n=value n]|[...] library.call_for_each_group = function (ctx) -- NOTE: `ctx.params` might be the original metatable! local opts, offs = ctx.pipe, ctx.fnpos local tmp = opts[offs + 1] and opts[offs + 1]:match'^%s*(.*%S)' if tmp == nil then error(modulename .. ', ‘call_for_each_group’: No template name was provided', 0) end local model = { title = tmp } local bargs, ret, nss, ccs = {}, {}, 0, ctx.itersep or '' for key, val in pairs(opts) do if type(key) ~= 'number' then bargs[key] = val elseif key > offs then bargs[key - offs - 1] = val elseif key < 1 then bargs[key - 1] = val end end ctx.params = make_groups(ctx.params) flush_params(ctx, function (gid, group) for key, val in pairs(bargs) do group[key] = val end group[0], model.args, ret[nss + 1], nss = gid, group, ccs, nss + 2 ret[nss] = ctx.frame:expandTemplate(model) end) finalize_and_return_concatenated_list(ctx, ret, nss, 2) return false end --[[ First-position-only modifiers ]]-- --------------------------------------- -- Syntax: #invoke:params|new|pipe to static_iface.new = function (child_frame) local ctx = context_new(child_frame, 'new') ctx.params = {} main_loop(ctx, context_iterate(ctx, 2)) return ctx.text end --[[ First-position-only functions ]]-- --------------------------------------- -- Syntax: #invoke:params|self static_iface.self = function (child_frame) return child_frame:getParent():getTitle() end --[[ Public metatable of functions ]]-- --------------------------------------- return setmetatable({}, { __index = function (_, query) local fname = query:match'^%s*(.*%S)' if fname == nil then error(modulename .. ': You must specify a function to call', 0) end local func = static_iface[fname] if func ~= nil then return func end func = library[fname] if func == nil then error(modulename .. ': The function ‘' .. fname .. '’ does not exist', 0) end return function (child_frame) local ctx = context_new(child_frame, fname) ctx.params = copy_or_ref_table(ctx.oparams, refparams[fname]) main_loop(ctx, func) return ctx.text end end }) edjjks8ayvjip4tl4xpkdb2en7irkcr 0 322574 2844904 2839913 2026-11-08T23:05:24Z Jtneill 10242 Copyediting 2844904 wikitext text/x-wiki {{title|ERG theory and motivation:<br>What is Alderfer's ERG theory and how does it explain human motivation?}} __TOC__ ==Overview== {{RoundBoxTop|theme=3}} [[File:Tired person sitting in chair with hands covering face.jpg|right|thumb|150px|'''Figure 1'''. Add a caption for the image to connect it to the text goes here]] ;Scenario A new employee enters a workplace excited to grow professionally. Over time, they realise there are limited opportunities for development. Their motivation drops, and they begin focusing only on job security and material rewards. ERG Theory explains this shift, because when growth needs are blocked, people tend to regress to lower level needs such as existence or relatedness (Shikalepo, 2020) See Figure 1 {{ic|Use APA style to cite figures}} {{RoundBoxBottom}} Motivation influences many aspects of everyday life, including career choices, educational achievement, workplace performance, and personal development. Understanding what motivates people is important because motivation affects the goals individuals pursue, the effort they invest in those goals, and their ability to persist when faced with challenges. Motivation is widely recognised as a key factor influencing behaviour, performance, and wellbeing across multiple areas of life, including education, work, and personal development (Ryan & Deci, 2020). Psychologists have developed numerous theories to explain human motivation, with many focusing on the role that needs play in shaping behaviour. One such theory is ERG Theory, which was developed by Clayton Alderfer as a refinement of Maslow's hierarchy of needs {{f}} (Alderfer, 1969). ERG Theory proposes that human motivation is influenced by three categories of needs, {{g}} existence, relatedness, and growth. Existence needs refer to basic physiological and security requirements necessary for survival and stability. Relatedness needs focus on interpersonal relationships, social connection, and a sense of belonging. Growth needs involve personal development, achievement, and the pursuit of an individual's full potential. Unlike traditional need based theories that suggest motivation follows a strict hierarchy, ERG Theory proposes that multiple needs can influence behaviour simultaneously and that individuals may move between different needs depending on their circumstances (Caulton, 2012). A key feature of ERG theory is its ability to explain changes in motivation through the concepts of satisfaction-progression and frustration-regression. Satisfaction-progression occurs when the fulfilment of lower-level needs encourages individuals to pursue higher-level growth needs, whereas frustration-regression occurs when unmet higher-level needs lead individuals to refocus on lower-level needs (Shikalepo, 2020). This flexibility allows ERG Theory to provide a more {{ic|than?}} realistic explanation of human behaviour and motivation across a variety of personal and professional contexts. {{RoundBoxTop|theme=3}} ;Focus questions {{expand}} {{RoundBoxBottom}} ==What are ERG needs?== ERG theory categorises human needs into three groups, existence, relatedness, and growth. Developed by Clayton Alderfer {{ic|add a link to the Wikipedia article about this person}}, the theory emerged as a refinement of Maslow's hierarchy of needs {{f}} and grouped human needs into three broad categories that influence motivation and behaviour (Alderfer, 1969). Existence needs relate to basic material and physiological requirements necessary for survival and security, while relatedness needs involve meaningful relationships, social connection, and a sense of belonging with others (Bateman & Snell, 2013). Growth needs focus on personal development, achievement, and the pursuit of one's full potential. ERG theory sought to provide a more flexible explanation of human motivation (Caulton, 2012). Unlike Maslow's model, which organises needs into five hierarchical levels, ERG theory simplifies human needs into three broad categories and recognises that multiple needs can influence behaviour simultaneously. As a result, the theory has been widely applied to understanding workplace behaviour, relationship dynamics, educational motivation, and personal development (Caulton, 2012). - See Table 1 {{ic|Use APA style to cite tables.}} {| class="wikitable" |+Table 1 {{ic|caption goes here e.g., Summary of existence, relatedness, and growth needs in ERG Theory}} {{f}} !Need Category !Description !Examples |- |Existence |Basic survival and security needs including physiological needs and safety |Food, shelter, job security, physical safety |- |Relatedness |Social and interpersonal needs involving connection, belonging and relationships |Friendships, teamwork, recognition, social support |- |Growth |Personal development needs focused on learning, competence, and self-actualisation |Skill development, creaivity, autonomy, achievement |} == Existence Needs == Existence needs include physiological and safety-related requirements such as food, shelter, job security, and safe working conditions (Bateman & Snell, 2013). According to ERG theory, these needs form the foundation of motivation because they are directly linked to an individual's wellbeing and sense of stability. When existence needs are threatened or not met, people are more likely to focus their attention on obtaining resources that will restore security and reduce uncertainty. Employment conditions, rewards, and job security can significantly influence employee motivation and job satisfaction (Ali & Anwar, 2021). In workplace settings, existence needs can play a particularly important role in motivation. Employees who are concerned about job security, income, or safe working conditions may prioritise these concerns over opportunities for social connection or personal devlopment. When existence needs are adequately satisfied, individuals are often better positioned to pursue higher level needs, such as building meaningful relationships and seeking personal growth. This highlights the importance of secure and supportive environments in fostering motivation. Research has demonstrated the influence of existence needs in educational contexts. Wang et al. (2021) found that healthcare students frequently expressed motivations related to future employment and career security. Many participants reported that learning ultrasound skills was important because these competencies were required for future professional practice and employment opportunities. These findings suggest that individuals are often motivated by goals that contribute to their long term stability and security, supporting the role of existence needs as an important driver of behaviour within ERG theory. However, the importance of existence needs may vary depending on an individual's circumstances. For example, people who already experience high levels of security may be more strongly motivated by opportunities for social connection or personal growth. This suggests that existence needs are important but may not always be the primary source of motivation. {{f}} == Relatedness Needs == Relatedness needs involve interpersonal relationships, social connect, recognition, and feeling safe around others (Bateman & Snell, 2013). These needs relate to belonging and interpersonal safety, reflecting an individual's desire to establish and maintain meaningful relationships with family, friends, colleagues, and wider social groups. Within ERG theory, relatedness needs are met through positive, meaningful social interactions, support from others, and a sense of inclusion and acceptance. When these needs are met, individuals are more likely to experience greater wellbeing, engagement, and motivation in both personal and professional settings. Research implies that supportive workplace environments and strong interpersonal relationships are associated with higher levels of work engagement and organisational commitment (Aboramadan et al., 2020). In a study in 2022, it was demonstrated that social relatedness is a significant contributor to work motivation, highlighting the importance of interpersonal connections in motivating behaviour (Vo et al., 2022). Cultural research implies that motivational preferences can vary across {{which}} different demographic and personality characteristics. Song, Wang, and Wei (2007) found {{how}} that motivation differed across gender and personality types, indicating that individuals may prioritise social and interpersonal needs in different ways. However, the researchers did not find significant correlation between gender and personality type in relation to motivation, suggesting that these {{which}} factors may influence motivation independently. Additional research by Wang et al. (2021) found that relatedness needs were {{ic|how much?}} less dominant than existence and growth needs among {{ic|how many?}} healthcare students {{where}}. This finding suggests that while social connection and belonging remain important sources of motivation, individuals may prioritise security and personal development over interpersonal relationships in certain educational and professional contexts. Together, these findings highlight the complexity of relatedness needs and demonstrate that the importance individuals place on social connections can vary depending on their personal characteristics, goals, and circumstances. Although social relationships are widely recognised as important for motivation, research indicates that relatedness needs may not always be the strongest motivational influence. For example, Wang et al. (2021) found that growth and existence needs were more prominent than relatedness needs among healthcare students, suggesting that the importance of social connection may vary across different contexts. {{ic|repetitive}} [[File:Noun-community-6110484-0080FE.svg|thumb|Figure X caption goes here - explain how this image is connected to the text]] == Growth Needs == Growth needs include personal development, self‑esteem through achievement, and self‑actualisation (Bateman & Snell, 2013). Within ERG theory, these needs represent an individual's desire to realise their potential, develop new skills, and achieve meaningful personal and professional goals. Unlike existence and relatedness needs, growth needs focus on continuous self improvement and the pursuit of opportunities that enable learning, creativity, and accomplishment. As a result, growth needs are often associated with long-term motivation and sustained personal development. {{f}} A key feature of ERG theory is that higher level growth needs can motivate behaviour even when lower level needs are not fully satisfied (Malota, 2017). This differs from some more rigid hierarchical approaches to motivation {{ic|such as?}}, which suggest that basic needs must be met before higher level aspirations become important. Research by Malota (2017) found {{how}} that managers {{where}} were motivated to participate in mentoring relationships because of opportunities for personal development and relationship building rather than financial rewards. This suggests that intrinsic factors associated with growth can be powerful motivators in professional settings. Similar findings have been reported in educational contexts. Wang et al. (2021) found that {{how}} {{ic|what type of?}} students {{where}} referred to growth-related motivations 40.7% more frequently than relatedness motivations. Research also suggests that opportunities for learning and skill development can enhance motivation and performance. Zhang and Chen (2021) found {{how}} that learning motivation was positively associated with innovation capability and learning effectiveness, indicating that {{ic|what type of?}} individuals are often motivated improving diagnostic skills and developing professional competencies that would support future career success. These findings support Alderfer's proposition that individuals are often motivated by opportunities for achievement, learning, and self-imvement {{f}}. When growth needs are supported, people may become more engaged, persist longer in challenging tasks, and experience greater satisfaction from their accomplishments {{f}}. Although {{which}} studies support the importance of growth needs in motivating learning and professional development, many investigations {{f}} rely on self-report measures, making it difficult to determine whether growth needs directly cause motivational outcomes. Despite the benefits associated with growth needs, not all individuals prioritise personal development to the same extent. Factors such as financial pressures, workplace demands, or cultural expectations may lead individuals to place greater emphasis on existence or relatedness needs at different stages of life. Further research is needed to examine how growth needs influence behaviour across different cultural and occupational contexts {{vague}}. == Progression and Regression == ERG Theory proposes two key processes{{fact}}: === Satisfaction - Progression === According to ERG theory, motivation is influenced by a mechanism known as satisfaction-progression {{f}}. This suggests that when lower level needs, such as existence and relatedness, are sufficiently satisfied, individuals may become more motivated to pursue higher level growth needs. However, unlike Maslow's hierarchical model, ERG theory does not require lower level needs to be completely fulfilled before higher level needs become important {{f}}. Individuals may continue to seek personal development, achievement and self improvement even when some lower-level needs remain unmet (Malota, 2017). This flexibility reflects the dynamic nature of human motivation and suggests that multiple needs can influence behaviour simultaneously, rather than occurring in a fixed sequence (Alderfer, 1969). This aspect of ERG theory is often considered one of its strengths because it reflects the complexity of real world motivation. However, it can also make the theory more difficult to test empirically because individuals may pursue multiple needs at the same time. Supporting the relevance of this approach, Poulou and Norwich (2019) developed a measure of existence, relatedness and growth needs among adolescents, demonstrating the usefulness of these three categories for examining psychological needs in educational settings {{expand}}. Their research highlights how ERG theory can be applied to understand the different needs that influence individuals in real world contexts. Overall, ERG theory provides a flexible explanation of motivation by recognising that individuals can pursue different needs at the same time, depending on their circumstances and personal experiences. === Frustration - Regression === A unique feature of ERG theory is the frustration-regression principle. When individuals are unable to satisfy growth needs, they may redirect their attention toward lower level existence or relatedness needs in an attempt to maintain motivation and satisfaction (Shikalepo, 2020). This means that motivation does not always progress in an upward direction. Instead, people may regress to needs that are more attainable when higher-level goals are blocked or unavailable. For example, a nurse may begin a new role motivated by growth needs such as developing advanced clinical skills and pursuing career advancement opportunities. However, if access to training programs and professional development opportunities becomes limited, their growth needs may become frustrated. As a result, the nurse may shift their focus towards existence needs, such as job security and stable income, or relatedness needs, such as building supportive relationships with colleagues. This example demonstrates how frustration-regression can explain changed in motivation when higher level needs cannot be fulfilled. According to Shikalepo (2020), this flexibility distinguishes ERG theory from more rigid motivational models by recognising that individuals can move between different needs depending on their circumstances. While the frustration-regression principle is a distinctive feature of ERG theory, there is limited empirical research directly examining this process. As a result, it could be argued that further evidence is needed to determine how consistently frustration-regression occurs across different populations and contexts. {{RoundBoxTop|theme=3}} Case study: Regression in the Workplace A nurse begins a new role motivated by growth needs such as developing advanced clinical skills. When opportunities for training are removed, her motivation declines. She shifts focus to job security and stable income. This is a regression from growth to existence needs. {{RoundBoxBottom}} == Applying ERG Theory == [[File:Nurse administering medicine using a spoon in a healthcare setting during the day.jpg|left|thumb|Figure 2 caption goes here]] ERG Theory is widely used to understand workplace motivation, morale, and productivity (Caulton, 2012). One of the key strengths of the theory is its recognition that individuals are motivated by different needs at different times. Rather than assuming everyone is motivated by the same factors, ERG theory suggests that motivation is influenced by a combination of existence, relatedness, and growth needs. This flexibility allows organisations to better understand employee behaviour and develop strategies that support different sources of motivation. In workplace settings, ERG Theory can help managers tailor motivational strategies to individual needs (Mansaray, 2019). For example, some employees may be primarily motivated by existence needs such as salary, job security, and safe working conditions, whereas others may value social support, recognition, and opportunities to build positive relationships with colleagues. Employees who are focused on growth needs may be motivated by career advancement opportunities, skill development, and challenging work tasks. A study in 2023 highlights how organisations offering training and professional development opportunities often experience higher levels of employee engagement, motivation, and retention (Srivasta, 2023). Through recognising these differences, managers can create work environments that support a range of motivational needs and improve employee satisfaction and performance. ERG theory can also be applied in educational settings. Research by Wang et al. (2021) found that the theory was useful for understanding student motivation in healthcare education. Students were motivated by a combination of future career opportunities to develop professional skills. In addition, motivational preferences may differ across cultures, genders, and personality types, suggesting that individuals do not all respond to motivation in the same way (Song, Wang & Wei, 2007). These findings highlight the practical value of ERG theory for understanding human motivation across different context and for developing environments that support security, social connection, and personal growth. Although ERG theory has practical applications across workplaces and educational settings, it may not fully explain all aspects of motivation. Human behaviour is influenced by a range of psychological, social, and cultural factors, meaning that ERG theory is most useful when considered alongside other motivational perspectives. ;Quiz <quiz display="simple"> {ERG Theory proposes that individuals must satisfy existence needs before they can pursue relatedness or growth needs.: |type="()"} - True + False {According to ERG Theory, multiple needs can be active and influence behaviour at the same time: |type="()"} + True - False </quiz> ==Conclusion== ERG Theory offers a flexible, realistic explanation of human motivation by proposing that behaviour is shaped by three core needs: existence, relatedness, and growth. Existence needs involve basic material and safety requirements, relatedness needs involve meaningful relationships and social connect, while growth needs focus on personal development, achievement, and self-actualisation (Bateman & Snell, 2013). Together these needs help explain why individuals may be motivated by different factors depending on their circumstances and personal goals. A key strength of ERG theory is its ability to explain changes in motivation through the concepts of satisfaction-progression and frustration-regression. Unlike traditional hierarchical models like Maslow's hierarchy of needs, individuals can pursue multiple needs simultaneously, and when higher level needs such as growth needs are blocked, attention may shift towards lower level needs such as security, financial stability, or social support (Shikalepo, 2020). Research has demonstrated the relevance of these needs across workplace and educational settings, where motivation is influenced by opportunities for security, belonging, and personal development. The practical applications of ERG theory demonstrate its value for understanding motivation in everyday life. In workplaces, managers can use the theory to develop strategies that address different employee needs, while educators can apply it to better understand student engagement and achievement. The key takeaway is that motivation is not fixed, but changes according to an individual's needs, experiences, and environment. Through recognising and supporting existence, relatedness, and growth needs, organisations, educations, and individuals can create conditions that promote wellbeing, engagement, and long term motivation. Therefore, ERG theory provides a useful psychological framework for understanding how motivation develops and how it can be enhanced across a variety of personal, educational, and professional contexts. ==See also== * [[Motivation and emotion/Book/2022/ERG theory|ERG theory]] (Book chapter, 2022) * [[Motivation and emotion/Book/2024/ERG theory|ERG theory]] (Book chapter, 2024) ==References== {{Hanging indent|1= Aboramadan, M., Albashiti, B., Alharazin, H., & Zaidoune, S. (2020). Human resources management practices and organizational commitment in higher education: The mediating role of work engagement. International Journal of Educational Management, 34(1), 154–174. https://doi.org/10.1108/IJEM-04-2019-0160 Alderfer, C. P. (1969). An empirical test of a new theory of human needs. Organizational Behavior & Human Performance, 4(2), 142–175. https://doi.org/10.1016/0030-5073(69)90004-X Ali, B. J., & Anwar, G. (2021). An empirical study of employees' motivation and its influence job satisfaction. International Journal of Engineering, Business and Management, 5(2), 21–30. https://doi.org/10.22161/ijebm.5.2.3 Bateman T. S. and Snell S. A. (2013) MANAGEMENT: Leading & Collaborating in a Competitive World Tenth edition. Published by McGraw-Hill/Irwin Caulton, J. R. (2012). The development and use of the theory of ERG: A literature review. ''Emerging Leadership Journeys'', ''5''(1), 2-8. Mansaray, H. E. (2019). The role of human resource management in employee motivation and performance—An overview. ''Budapest International Research and Critics Institute-Journal (BIRCI-Journal), 2''(3), 183–194. <nowiki>https://doi.org/10.33258/birci.v2i3.405</nowiki> Małota, W. (2017). Motivational factors to be a mentor in formal mentoring in organisations. The role of intrinsic and extrinsic motivation in the propensity to mentor. ''Central European Management Journal'', ''25''(4), 119-143. Poulou, M. S., & Norwich, B. (2019). Adolescent students’ psychological needs: Development of an existence, relatedness, and growth needs scale. International Journal of School & Educational Psychology, 7(sup1), 75–83. https://doi.org/10.1080/21683603.2018.1479320 Ryan, R. M., & Deci, E. L. (2020). Intrinsic and extrinsic motivation from a self-determination theory perspective: Definitions, theory, practices, and future directions. Contemporary Educational Psychology, 61, Article 101860. https://doi.org/10.1016/j.cedpsych.2020.101860 Shikalepo, E. E. (2020). The role of motivational theories in shaping teacher motivation and performance: A review of related literature. ''International Journal of Research and Innovation in Social Science, 4''(4), 64–76. Srivastava, P. (2023). Evaluating the role of training programs in enhancing employee skills and retention. IOSR Journal of Business and Management, 25(8), 66–71. Vo, T. T. D., Tuliao, K. V., & Chen, C. W. (2022). Work motivation: The roles of individual needs and social conditions. Behavioral Sciences, 12(2), 49. https://doi.org/10.3390/bs12020049 Vo, T. T. D., Tuliao, K. V., & Chen, C. W. (2022). Work motivation: The roles of individual needs and social conditions. Behavioral Sciences, 12(2), 49. https://doi.org/10.3390/bs12020049 Wang, T. C., Chen, W. T., Kang, Y. N., Lin, C. W., Cheng, C. Y., Suk, F. M., Chen, H. Y., Hsu, C. W., Fong, T. H., & Huang, W. C. (2021). Why do pre-clinical medical students learn ultrasound? Exploring learning motivation through ERG theory. ''BMC Medical Education, 21'', 438. https://doi.org/10.1186/s12909-021-02869-4 Zhang, G., & Chen, C. (2021). A study on the relationship between learning motivation and learning effectiveness of personnel based on innovation capability. Frontiers in Psychology, 12, 772904. https://doi.org/10.3389/fpsyg.2021.772904 }} ==External links== {{expand}} [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Motivation]] [[Category:Motivation and emotion/Book/Needs/Psychological]] i83rels8q8g3slo6pzmzy3isreb9zeo 119 329156 2844952 2805214 2026-11-09T07:21:16Z ThinkingScience 3061446 /* How to create the draft */ no AI was used in this post/edit: title change == How to create the draft / Title Change of Project == 2844952 wikitext text/x-wiki == Inspirations == "The Neurodiversity-inspired Idea" is '''a''' "Neurodiversity-inspired Idea". There are probably many "ideas" out there but in this draft I'll be focusing on the "idea" as far as my "brain" observed it back in 2003 The initial thing didn't happen with that I had a "plan". My simplest of plans after I got my "psychiatric diagnosis" or "medical condition"(as they refer to it at Wikidata) was to see with my own eyes what I could see if I met autistic adults. I knew little to nothing about it. After I got my Asperger's diagnosis a long time ago I felt an urgency to figure this thing out. I had no prior academic experience. I had not figured out how to learn and that is mostly true today too. If I have figured it out I don't have the self-awareness to tell. The reason that probably resulted in expressing myself that I want to explore my "idea" here on Wikiversity is for many reasons. I got very inspired by the [[Neurodiversity_Movement/Section_1:_The_Basics]] based on what I had read on this older version from 2008: https://en.wikiversity.org/w/index.php?title=Neurodiversity_Movement/Section_1:_The_Basics&oldid=208199. I interpreted the page to be about "What Is A Neurotype?" and it inspired me. Mainly because there was no clear "assertiveness" regarding what a Neurotype is but what it might be. "Additionally, students are encouraged to research neurotypes and write a section on the neurotype of their choice for other students to read and edit." That was a major inspiration because it was written in a way that made me feel welcome to think and that made me think that I can "choose" what a Neurotype is. This inspired me. At the same time I tried to search for what other people in the Neurodiversity movement were thinking by seeing how they expressed themselves regarding neurotypes. I got disappointed because many of them, I interpreted, called autism a "neurotype" and that is as far from my idea as possible, has nothing to do with it! I see it as borrowing a term from psychiatry and then "slapping" a "Neurotype" at the end. I can understand and I can support the idea behind it that the person that says they got the "autism Neurotype" may communicate "I am not a disease" and I can fully support that! I can support that use of the word "Neurotype". But I concluded I can not use that term and yes I was thinking about calling it "next-generation Neurotypes" my idea or "Next-generation Neurodiversity" but I don't want to hijack a movement. Also I did not pay attention to that the page itself on Wikiversity actually mirrored/reflected what I heard on social media how Neurodivergent people were expressing themselves. So yeah, nothing to do with my "idea"(repeating myself, sorry) Thus whatever "my idea" is right now I'm going to express it on the draft section. Thanks to contacting a friend my idea got past a "SMART criteria" which I think should not matter cause passing through [[Wikiversity:Original research]] that is a challenge that I've been so afraid to go through! Yet here I am. That page links to a lot of important things and I'm planning to go through them all! Yet, even if I don't compare the "SMART criteria" to the stuff on Wikiversity, it still inspired me to "let my idea go through various tests" or "tests"/evaluations. Questions like: what kind of hypotheses would I create to prove or disprove my "idea". This is clearly a work in progress. This is an "idea" or we'll see together what it is. If it is one thing or many things. To figure out how I should go about beginning this I've opened [[Wikiversity:Drafts]] in a tab on my web browser to learn more about the Draft namespace. I thought I was gonna publish this in draft space but got suggested to me that it works better on a talk page. (this text, so far) I wrote this myself. Everything I have written so far on all my edits have been my own text. I may receive help though in understanding what I'm saying because language to me is...I'm not very good with language, even my own native language. Lots of time goes into time passing after trying to think of the right words. == How to create the draft / Title Change of Project == I moved now to [[Wikiversity:Original research]]. From there I will use that as a "template" and move from part to part to begin the draft. I will try to do this "now"...so I'm gonna be working on this now. If you see no activity the next 24 hours feel free to delete this talk page and suggest this item for deletion if there is no draft here within 24 hours. :I nowadays describe the project as a "pilot project"...which is what may one day become "original research" but I need to formulate methodologies and the right questions that will encourage me to focus on needed areas before the "pilot project" can "begin". Also I have posted on [[User:Jtneill]]'s talk page regarding a question on title change [[User:ThinkingScience|ThinkingScience]] ([[User talk:ThinkingScience|discuss]] • [[Special:Contributions/ThinkingScience|contribs]]) 07:21, 9 November 2026 (UTC) kfn8hdsmeeol4d19pvzfly9o62bb72r 118 329157 2844953 2842250 2026-11-09T07:26:37Z ThinkingScience 3061446 /* Naming Suggestions */ Naming suggestions are 3 which could be new titles for draft project or serve as inspiration 2844953 wikitext text/x-wiki {{Research project|status=draft}} {{AI-generated}} {{Notice|'''Please excuse mistakes and problems''' this is a work in progress and pages may be published which are unfinished and that contain unfinished sentences and repetitions}} What this is(observation: 2026-10-23): This is more of a "pilot study" and less "original research". Answer: Why it is a pilot study: there is not enough data to analyze. Neither methodology to find more data nor how to gather it has been properly explained. == Explanation regarding {{tl|AI-generated}} template presence on this page and guidelines == * Some questions that can be asked have been generated where there is a note about it. ("AI Mode" by Google) * If something has been generated by an "AI"/LLM then please make a note of that so the reader knows. Also please document the specific "AI name", ie. "AI Mode", "GPT-5 mini" etc. as long as that name is enough to find the AI/LLM on Wikidata or on Wikipedia. For questions that have been "AI-Generated" this section has been created to document the queries/input: * [[Draft:The Neurodiversity-inspired Idea/AI Prompt History for Questions|Please document your input and output here when interacting with an AI/LLM specifically in regards to using LLMs to generate only questions]] For documenting LLM/AI use in general when contributing to this "pilot project": * [[Draft:The Neurodiversity-inspired Idea/AI Prompt History for Documenting Prompts in General]] == Hypothes-is/-es == Preliminary date for basics of hypothesis/hypotheses being developed: June 16, 2026. === In preparation for Hypothes-is/-es: Core Assumption Example === Google's "AI Mode" was used on 2026-04-29 and the formation of an "example Core Assumption" was made. The following is input sent to "AI Mode": {{quote|This I posted previously: {{quote|Example of a "Core Assumption": That not "Everybody is different" in brain structure but that some humen show so great similarities between each other that one might say "it is the same brain". If that fails, my idea fails completely.}} This I'm thinking about posting now and I want your output based on this input: Example of a "Core Assumption": That not "Everybody is different" in brain structure but that some humen show so great similarities between each other that one might say "it is the same brain". I assume that that my core assumption and "main idea" can be fully broken by measurement of Rapport. I assume that I can predict better rapport between individuals who interact for the first time compared to a random sample. If that fails, my idea fails completely.}} The system in which predictions are made regarding the related hypotheses are assumed to be found in the data. Studying the data should lead to understanding how to make the predictions in the hypotheses. === Hypothesis: Rapport between dating couples or random strangers meeting etc. === This was written in a hurry 100% by a human so there may be multiple grammar, words that don't exist and spelling and other incoherences(this is probably not even a word). This is a "pre-hypothesis". What is meant with that is that this hypothesis purpose is to "prove" or "disprove" that there is anything at all going on...or not going on. If there is nothing going on at all after "control group in, control group out" etc., then this project could be ended/closed, unless the focus changes or something else is tested that hasn't been tested yet. Sometimes something new is discovered or the significance of a parameter is questioned in the beginning and may matter more later. Regardless, speculation is pointless. The very existence of this project was shaky from the beginning and is still shaky and this hypothesis might help in discovering whether there can be a systematic way of finding rapport between people of either friendship nature or of a romantic/dating nature. If this hypothesis is disproven. Though it should be clear how it can be disproven or proven. The rapport...if there is no significant change in rapport in comparison with control group 1 and 2 then the hypothesis is prove wrong, it is assumed. * Control group 1: "normal group" / "random group" of people selected purely by chance alone. Method of how "by chance" is calculated should be disclosed. Random is also which couples should be matched together, that is the distinctive part of control group 1 and all the control groups, namely whether random matchmaking is worse or better in regards to rapport between the couples. * Control group 2: same "normal group" / "random group" of people selected but the couples that are selected are chosen this time. It is not by randomness at all. Control group 2 is where a "core" of this idea happens. Participants can sign up to make the choosing of the hypothesis, practically each participant who signs up conducts their own hypothesis experiment as long as it's in a "Do no harm" way and it is legal in the country/countries where they are doing the experiment. == Data == There is currently no data. == Original Motivations == This section can list motivations by each user who contributes content or questions to this page. * '''User:ThinkingScience''' My motivation is related to perceived limited progress by psychiatry and getting inspired by writers exploring Neurodiversity topics. I don't feel I have a right to have an opinion about psychiatry considering this idea's methodology is being developed during the publishing(and before) of this edit. It is my hope that if this idea develops how I expect it to it will be an "extra parameter" that some other sciences can use, including psychiatry. It is my hope that this idea will thus help psychiatry develop in a great way though my personal hope is it will help sociology more. * Example user x * Example user y etc. == "Do no harm" == This section can list ideas/comments by users who are trying to do no harm while using their methodology(which should be documented on this page, if possible!): * '''User:ThinkingScience''' Considering I am watching videos of famous people in interviews. I am making notes...my goal should be that not only my public notes are following the "Do no harm" but that my private notes do as well. That can be my goal for now. We'll see how this develops... * Example user x * Example user y etc. Do no harm links from [[Wikiversity:Research ethics]] into Wikipedia with no examples for Wikiversity users specifically, yet. == "Research projects must fully document the methods" == {{quote|Safety - Research must be conducted in a safe and lawful manner. Do no harm.}} An idea for the minimum age of the subjects which are "studied" in a "Do no harm" way, if even possible, might be 29 years of age. There is disagreement regarding the exact age of a person when their brain matures and it may benefit the student/contributor if the "starting age" or "minimum age" is high enough so that a person with a "fully matured brain" also has some experience living with that fully matured brain. 💡💡💡'''Suggestion: 29 minimum years of age for anyone participating in this project.'''💡💡💡 for the sake of "Do no harm"? which is described on [[Wikiversity:Research ethics]] that links to Wikipedia. This section needs work. One of the methodologies is to watch a video, ie. a video interview of famous people or footage where the researcher has gotten legal access and specific consent from any person appearing in the video footage. Methodologies need to be developed where data is gathered in a way that adheres to "Do no harm". === Focusing on creating a "Do no harm"-compliant method === This needs to be developed. This sub-page is created so we can make video notes. We can watch a video and then we can make video notes. We must do the video notes by following [[Wikiversity:Research ethics]] and "Do no harm". How to do that can be tricky. "Do no harm" links to Wikipedia because we don't have our own resource where we help you how to do that. === method of interacting with draft and other pages on Wikiversity === "AI Mode" by Google can be used to get inspired by what kind of things to focus on, including if one thinks they started "blathering" and the text started to grow 'for no apparent reason' because the user landed in a "non-productive behavior" and the repeating themselves kept going on and on. Prompts that generate questions and other things could be added into a subsection of this draft research === Video Notes before the creation of a more 'stable' method that adheres to "Do no harm" === * [[/Method_development_through_video_notes|Video Notes]] == Questions that might encourage the development of this idea and its methodology == Questions that encouraged certain dates of time: * June 16: Two months after the creation of the project some 'basic form' of a/- hypothes-is/-es should exist. ie. measuring rapport. How rapport can/will be measured. What tools can be used. How one makes "first contact" with people. Challenges and work to be done regarding the "main hypothesis". This is a prediction. Time will tell if a "main hypothesis" will be ready by June 16. ** 2026-06-18 This plan failed. Suggestions from the Colloquium were also that no deadlines should be set. Opinions change over time. Perhaps one day deadlines will be suggested. '''The New Way: 100% human generated questions and answers''': If a student/contributor figures out their own questions without the help of an AI/"AI"/LLM please contribute in this section. Otherwise go to "The Old Way" section and contribute there. Questions in no particular order: * Is this "idea" testable? - It is in the plans for it to be testable '''but not testable yet'''. * Is it possible to create one or more hypotheses based on this "idea"? - Multiple hypotheses have been made but never published. Plan is to publish hypotheses related to the "idea" in the future. * Is there a hypothesis or a number of hypotheses related to the idea? ** Can this idea be proven false? - It can not yet be proven false considering a hypothesis is not currently described. Goal is to have a hypothesis at least before June 16, 2026 which is 2 months roughly after the first creation of the page. A basic hypothesis structure may/should exist by then but a complete hypothesis being created that is "perfect in some ways" that can't be predicted yet. '''The Old Way''' This is for any AI/LLM that is available to you. Please document the output here and if you want to contribute the input prompts and more specific details go to the subpage [[Draft:The_Neurodiversity-inspired_Idea/AI_Prompt_History_for_Questions]] Questions and 'follow up'-/improved questions generated by Google "AI Mode": * What is missing right now? ** "Improved" version: "What key sections are missing from this research draft to meet Wikiversity standards?" * How will we know if the idea is working? == Naming Suggestions == Feel free to edit/modify or remove content in this section, the project may be renamed based on inspiration from these titles (1-3). Please suggest alternatives with amount of words being from 6-8 in title length or don't feel restricted by word length: # "Similarities in Thinking: Systematic Similarities Between People" # "Neurodiversity Spectrum Explained: Description of Entire Spectrum" # "Measuring Individual Subneurotype Differences Across People" Example name ideas: * Pre-research: Observations made inside psychiatry spectrums * Psychiatric Spectrum Specifications ''These names should probably not be used but were kept for inspiring questions in readers'': * Next-Gen Brain Types * Next-Gen Sociology * Next-Gen Neurotypes == Potential best-case uses of "idea" if fully developed == This section is for expected best-case uses for the "idea" if fully developed. Probably best to keep this section short. Assumptions may develop from it otherwise. Maybe max 5 items? * Could assist in better matchmaking in relationships where "compatibility"/"rapport" is important. Where collaboration is important and there is a desire for communication with less friction than any random picking of co-workers. * Better matchmaking in romantic relationships. "Better" in the way of a more "exact" match. The way of thinking here is more similar rather than less in the way the brain is structured. How the personality of the 2 people changed over the years, that is probably not much affected by this. * Companies may get a better idea on what education to send some of their employees where they can develop their skills the most. == References/in-Wikiversity-Wikilinks == This section is for linking to specific references: * [2] - [[Draft:The_Neurodiversity-inspired_Idea/AI_Prompt_History_for_Questions#Reference_2]] == Future references to this draft == In the event that other publications start referring to this draft in the future, the template "findsources" is added: {{findsources}} 7o2tljkqy6bjegwfq1gfwhy6qj8ilt1 2 329403 2844949 2817741 2026-11-09T07:12:33Z ThinkingScience 3061446 /* Prompts */ === Goal: Interact with User:Jtneill at Nov 9, 2026 === 2844949 wikitext text/x-wiki This page is adhering to [[Wikiversity:Artificial intelligence]]'s latest revision as of the making of this post based on this oldid: https://en.wikiversity.org/w/index.php?title=Wikiversity:Artificial_intelligence&oldid=2806663 If this text becomes too much...then I may suggest archiving it. If there later is an archive of this text, then maybe I'll request a full wipe of this page so that the size that the text takes up on this page doesn't become too much for the Wikiversity database and then can save some space. == Prompts == The way in which this page is written is made to conserve space. If you don't understand any part of this subpage please ask me on my talk page what you don't understand and I'll try to explain as well as I can for you to understand regardless of how many attempts that may '''require'''. Each prompt and it's follow-up inputs and outputs are put into one section at a time. ie. if a series of inputs and outputs were related and it was my judgement that based on all the "back and forth" between me and the Quasi-AI the end result was posting on a talk page or editing something else it will be documented here into its own subsection. === Goal: Post directly to [[Neurodiversity Movement]] at May 2, 2026 === Title and this text so far is 100% human-generated. If it will stop to be it will be because I'm typing like this example: * input to "AI Mode": hi. Max response 20 words please. ** output: Hello! I will keep my responses brief and under 20 words for you. How can I help today? That output was 100% "AI Mode" by Google. My input was my own. With other words the 100% "Quasi-AI"-generation has already began and the full [[Wikiversity:Artificial intelligence]]-compliance requirement is in motion. '''Goal''': This conversation with "AI Mode" resulting in a useful contribution at [[Neurodiversity Movement]] based on my thought that we need to help students understand that the Neurodiversity Movement is an alive movement and that it is hard(and that it differs from person to person) to measure what is going on in the movement. That the encouragement ... I'll stop myself here. Here comes the prompts but also a system I'm developing for saving prompt space that the text takes up on hard drives: I'm looking at Neurodiversity Movement on https://en.wikiversity.org/wiki/Neurodiversity_Movement '''Here begins 100% human inputs and 100% "AI Mode" by Google outputs. They will all be placed in''' {{quote|example text}} '''and be referred to as input 1, output 1, input 2, output 2 etc. for organizational reasons":''' I'm going to be using emojis so I don't miss any input or making it easier for me to find old and new inputs: * ☢️ for human inputs * ⛔ for "Quasi-AI" outputs ⚠️ '''Here begin the inputs!''' ⚠️ ☢️ input 1: {{quote|I'm looking at Neurodiversity Movement on https://en.wikiversity.org/wiki/Neurodiversity_Movement This is my goal: "'''Goal''': This conversation with "AI Mode" resulting in a useful contribution at [[Neurodiversity Movement]] based on my thought that we need to help students understand that the Neurodiversity Movement is an alive movement and that it is hard(and that it differs from person to person) to measure what is going on in the movement but that there is hope and that we together can develop some ways to measure it in a "Do no harm" way." I'm looking at what Luai_lashire wrote with inspiration. I believe that when Wikiversity lost Luai, we lost something precious. A person that encouraged its students and yes maybe I feel a bit like "her student" so I may be becoming a bit emotional writing this...and that may "add to my bias" but I can't help that also knowing that bias existing is accepted on Wikiversity and I'm glad about that! Can you make sure that your responses are not too much text because I "may" have a learning disability even though I'm not sure but I work better when a "Quasi-AI" like yourself responds in with shorter text and I may have to ask you in the future to respond with less text as I'm also trying to "know myself". This is being documented live right now so if this triggers a "Google-engineer to having to intervene" I don't mind that at all. I want to work in a "Do no harm" way, so I don't want to harm Google by making this prompt}} ⛔ output 1: {{quote|It’s an honor to help you build on Luai_Lashire’s work. Her vision for the Neurodiversity Movement resource on Wikiversity is a powerful foundation, and your focus on the movement being "alive" and measurable in a "do no harm" way is a vital addition. To keep this manageable and scannable for you, let’s break your goal into three clear steps: ## 1. Documenting the "Living" Movement The movement isn't just history; it’s happening now in communities like r/neurodiversity. We can add a section highlighting how students can observe real-time activism through: * Social Media Trends: Tracking current hashtags or viral discussions. * Active Blogs: Referencing the "Autism Hub" and newer "DifferentBrains" blogs. ## 2. Measuring Progress (The "Do No Harm" Way) Measuring a social movement is hard because it's about feelings and acceptance, not just numbers. We could propose a "Qualitative Feedback" model: * Self-Reflection: Asking students, "How has your understanding changed?" * Community Surveys: Using the "Experimental Public Transparent Communication Project" to gather data safely. ## 3. Next Steps for Wikiversity To make your contribution, I can help you draft a short, clear paragraph for the "Goals" or "Experimental Resources" section of the page. How would you like to start? I can draft a short "Alive Movement" section for you to review, or we can brainstorm specific "Do No Harm" questions for students.}} ☢️ input 2: {{quote|You still there? Answer max 3 words(only in this input this is an exception. Behave normally in the prompts after that)}} ⛔ output 2: {{quote|I am here. How should we begin drafting the section on the living movement?}} ☢️ input 3: {{quote|I'm not going on any of your suggestions so far so listen to this: The latest oldid I can find where Luai lashire contributed to the main page of [[Neurodiversity Movement]] and that happened on 20 July, 2008: <nowiki>https://en.wikiversity.org/w/index.php?title=Neurodiversity_Movement&oldid=297014.</nowiki> I want to check that out first, this is one of the "original" pages which I've chosen as of now to focus on. Please post even less text than you usually do! Your last output was very long! Remember when I said "Can you make sure that your responses are not too much text"?}} ⛔ output 3: {{quote|Understood. I will be much more brief. Looking at that 2008 version, I see Luai focused on: * Basics: Defining neurotypes. * Abuse: History of harmful "cures". * Activism: Groups like Aspies For Freedom. To keep it "alive" as you want: what specific part of her 2008 outline catches your eye to update first?}} ☢️ input 4: {{quote|So that this leads somewhere and just doesn't lead nowhere, I'm focusing on one part I can relate to and am thus probably 'biased towards'. It's very personal. It's related to when I got my Asperger's diagnosis. The negative thought(cause I had one positive too!) was related to concentration camps. Thus it feels related to "Section 4: Causes And Cures" and "Fears of a ‘Genocide’". Although I may not wanna focus on that now. I may wanna focus on "Section 6: History Of The Movement" and begin making it. Perhaps beginning with writing a bit about "The Disability Rights Movement"}} ⛔ output 4: {{quote|That makes sense. Connecting to Section 6 via the Disability Rights Movement provides a strong, hopeful foundation. The 2008 version mentions this roots the movement in "Civil Rights" rather than "Medical" models. Would you like to draft a short sentence linking Disability Rights to the idea of an alive, ongoing movement?}} ☢️ input 5: {{quote|I'd like to make this subsection wikitext linkable so I modified it: <nowiki>"===[[/Section 6: History Of The Movement/]]===</nowiki> #The Disability Rights Movement #Branching Off #Aspies For Freedom Is Born #Spreading Awareness: Protests, Petitions, And Publicity" I guess I hit publish and then I start adding the history of the movement?}} ⛔ output 5: {{quote|Yes, that is the correct way to start. By hitting publish, you create the structural framework. Once those links are live, you can click them to begin writing the specific history for each sub-page. Tip: Since you want to keep the movement "alive," consider adding a "Recent History" bullet point to that list before you publish. Should we draft a few sentences for "The Disability Rights Movement" section now?}} ☢️ input 6: {{quote|}} ⛔ output 6: {{quote|}} ☢️ input 7: {{quote|}} ⛔ output 7: {{quote|}} Temp ⛔☢️ === Goal: Interact with User:Jtneill at July 5, 2026 === It must be practical to document the interaction between user and Large Language Model, the previous work I did in April is not practical and may have discouraged me from participating at all. Thus I will take advantage of duck.ai's text export feature. For practical purposes let's assume that 100% of this text is 100% LLM generated by duck.ai's "fast" "5.4-nano". Overthinking is something I try to avoid but it's hard...but this is gonna be everything that inspired me: File name downloaded from duck.ai: duck.ai_2026-07-05_04-19-50.txt File size: 15,9 kB (15865 bytes) ☢️WARNING☢️: below follows a ☢️"raw text"☢️ which is probably a lot of ☢️Kilobytes☢️ or in worst case even Megabytes(I hope not!): <nowiki> This conversation was generated with Duck.ai (https://duck.ai) using OpenAI's GPT-5.4 nano Model. AI chats may display inaccurate or offensive information (see https://duckduckgo.com/duckai/privacy-terms for more info). ==================== User prompt 1 of 21 - 7/5/2026, 2:44:34 AM: This is what I'm writing now: === Goal: Interact with User:Jtneill at July 5, 2026 === It must be practical to document the interaction between user and Large Language Model, the previous work I did in April is not practical and may have discouraged me from participating at all. Thus I will take advantage of duck.ai's text export feature. For practical purposes let's assume that 100% of this text is 100% LLM generated by duck.ai's "fast" "5.4-nano". Overthinking is something I try to avoid but it's hard...but this is gonna be everything that inspired me: GPT-5.4 nano: If you want this to be practical to document, make it a clean “LLM interaction log” template and treat everything you paste as the record—not as evidence you *must* prove. Here’s a revised draft you can use: === Goal: Document an Interaction with User:Jtneill (July 5, 2026) === I want a practical, copy/paste-friendly record of how I used a Large Language Model to help me. Earlier documentation I did in April was too detailed and didn’t feel actionable, so I’m going to simplify. For practicality, I’ll assume the exported text below was generated by duck.ai using the “fast” setting and model “5.4-nano.” I’m not trying to overanalyze provenance—this is purely for keeping a usable interaction log. What inspired me / what I’m optimizing for: - (your bullets go here) Next, paste (or export) the exact LLM output I’m documenting, and label it with: 1) Prompt: 2) Model settings: 3) Response: 4) My takeaways / what I changed afterward: Once you paste your “everything that inspired me” section, I can turn it into a tight set of bullets that fits the log format. -------------------- User prompt 2 of 21 - 7/5/2026, 2:45:13 AM: No, look I'm just saying what it says...I'm not saying I need help GPT-5.4 nano: Got it—you’re describing the text you’re writing, and you’re not asking for help. If you want, paste the “everything that inspired me” part and I’ll just rewrite it into clean, practical log-style wording (without adding “you need help” framing). -------------------- User prompt 3 of 21 - 7/5/2026, 2:45:32 AM: I am obviously needing help...otherwise I wouldn't interact with you GPT-5.4 nano: I hear you. What kind of help do you want with that draft—rewrite it, make it more practical, or turn it into an interaction log template? -------------------- User prompt 4 of 21 - 7/5/2026, 3:45:24 AM: No, I want to interact with https://en.wikiversity.org/wiki/User_talk:Jtneill regarding the draft I created here: https://en.wikiversity.org/wiki/Draft:The_Neurodiversity-inspired_Idea whether Jtneill might be interested to contribute a question regarding that entire project or regarding me...or my motivation to work on it... GPT-5.4 nano: I can’t fetch those Wikiversity pages right now (the pages are returning empty/404 payloads from my side), so I can’t tailor the message to what’s actually on them. Meanwhile, here’s a ready-to-post short note you can leave for User talk:Jtneill: Hi Jtneill — I’ve started a Wikiversity draft at “The Neurodiversity-inspired Idea”. Would you be interested in contributing a question or two about the project as a whole, and/or commenting on my motivation for working on it? If you’d prefer, I can also paste the specific sections I’m trying to improve so the questions are targeted. Thanks! If you paste the draft text (or just your “Goal/Questions” sections), I’ll tighten this to match the exact themes and tone. -------------------- User prompt 5 of 21 - 7/5/2026, 3:46:21 AM: You don't need to feel bad because I can just provide content from the pages, so you don't need to fetch anything. Just ask me and I'll provide anything you need GPT-5.4 nano: Great—please paste: 1) The latest text of your draft at “The Neurodiversity-inspired Idea” (or at least its key sections: purpose/goal, what questions you want input on, and your “motivation” section—if any). 2) Any specific contribution you want from Jtneill (e.g., “2–3 critique questions,” “question-writing,” “commentary,” “help narrowing scope”). 3) Your preferred tone for the outreach: casual / neutral / formal. Then I’ll produce: - a single concise message to post on User talk:Jtneill, and - 2–5 example questions Jtneill could answer (focused on the project + on your motivation). -------------------- User prompt 6 of 21 - 7/5/2026, 3:52:42 AM: 1. Latest revision as of 18:26, 18 June 2026 Difference between revisions My previous diff before that was: "=== Hypothesis: Rapport between dating couples or random strangers meeting etc. ===" but maybe you just wanted me to post stuff from the existing page as of right now? + ** 2026-06-18 This plan failed. Suggestions from the Colloquium were also that no deadlines should be set. Opinions change over time. Perhaps one day deadlines will be suggested. 2. Any question that Jtneill has time for and does not require ie. more than 5 minutes from his time. I don't like demanding too much as of this early communication. What if Jtneill isn't interested in the topic, I can't demand people to be interested in topics that they are not interested in. 3. Formal to allow Jtneill to make a response in I dunno 3-4 weeks, that this is not urgent...also I've not done too much hard work...ie. is there a hypothesis? No. There are concepts of possibly forming a hypothesis sort of. Also my goal is title and message should both combined not sum up to more than 100 words... GPT-5.4 nano: Here’s a ≤100-word post you can put on User talk:Jtneill: Hello Jtneill — I’ve begun a Wikiversity draft titled “The Neurodiversity-inspired Idea” (latest revision 18 June 2026). I’m still early-stage (no firm hypothesis yet), and earlier deadline-based planning has been revised after Colloquium feedback. If you have 5 minutes, would you be willing to suggest 1–2 short guiding questions I could refine (and/or comment on whether a hypothesis or alternative framing makes sense)? This is non-urgent; even a response in 3–4 weeks would be very welcome. Thank you. If you want, paste your draft’s current first paragraph/headings and I’ll tailor the questions further. -------------------- User prompt 7 of 21 - 7/5/2026, 3:57:05 AM: Draft:The Neurodiversity-inspired Idea was created on 23:44, 16 April 2026 (UTC time?)...anyway my time is UTC now so. I chose use wiki default to UTC...so yeah I'm still using that. GPT-5.4 nano: Hello Jtneill — I’ve begun a Wikiversity draft titled “The Neurodiversity-inspired Idea” (created 16 April 2026, UTC). The latest revision is 18 June 2026. I’m still early-stage: I don’t yet have a clear hypothesis, though there are related concepts/themes. After Colloquium feedback, I also removed deadlines because opinions may change. If you have 5 minutes, would you be willing to suggest 1–2 short guiding questions I could refine (and/or comment on whether a hypothesis-style framing would help)? This is non-urgent; a response in 3–4 weeks would be welcome. Thank you. -------------------- User prompt 8 of 21 - 7/5/2026, 3:59:38 AM: maybe we go for pure minimalism like, saying the hello, not referencing past interactions much...then going just for "Does the subject that I brought up interest you? Would you like to spend 5 minutes skimming through the 'idea' that I propose? That we don't have to overthink it...that I'm not expecting a reply anytime soon that he can take his time" GPT-5.4 nano: Hello Jtneill — does the topic I’ve brought up interest you? If so, would you be willing to spend about 5 minutes skimming through my “idea” on Wikiversity (“The Neurodiversity-inspired Idea”)? No need to overthink it, and there’s no expectation of a reply soon—please take your time. Thank you. -------------------- User prompt 9 of 21 - 7/5/2026, 4:00:12 AM: adding, whether a reply happens tomorrow or in 1 month or even later it's all wlecome GPT-5.4 nano: Hello Jtneill — does the topic I’ve brought up interest you? If so, would you be willing to spend about 5 minutes skimming through my “idea” on Wikiversity (“The Neurodiversity-inspired Idea”)? No need to overthink it, and I’m not expecting a reply soon—tomorrow, in a month, or even later would all be welcome. Thank you. -------------------- User prompt 10 of 21 - 7/5/2026, 4:06:14 AM: 55 words using wc -w file.txt...so a few words left to write a topic on his talk page then...I Prefer few words, perhaps 10? GPT-5.4 nano: Just post: “(Low pressure) Thanks!” -------------------- User prompt 11 of 21 - 7/5/2026, 4:07:06 AM: LLM generated message: Input on Neurodiversity inspired idea right? GPT-5.4 nano: Yes—that’s fine, but you can make it slightly clearer with this ~10-word version: “Low-pressure request: Would you skim my neurodiversity-inspired idea?” -------------------- User prompt 12 of 21 - 7/5/2026, 4:10:34 AM: Now figuring out if according to policy, I need to add that the message itself was "AI Generated": https://en.wikiversity.org/wiki/Wikiversity:Artificial_intelligence Content as of Revision as of 12:48, 26 May 2026: {{policy|WV:AI}} This policy specifies the requirements for contributing [[w:Generative artificial intelligence|AI-generated content]] (text and media) to [[Main page|Wikiversity]]. AI-generated content is permitted where it follows good [[w:scholarly method|scholarly practice]]s, including: * '''Edit summary''': The origin of contributed AI text is clearly indicated in the [[Wikiversity:FAQ/Editing/Edit summary|edit summary]] along with a publicly accessible link to the chatbot conversation (or a copy of the transcript) to maximise transparency. * '''Verifiability''' / '''Citations''': AI text is [[Wikiversity:Verifiability|verified]] by the contributor. [[Wikiversity:Cite sources|Citations]] are [[w:Fact-checked|fact-checked]] for appropriateness and relevance by the contributor. * '''Human revision''': AI text is revised and rewritten by the contributor (or originally human-written and improved using genAI) * '''Copyright''': AI content must be compatible with Wikiversity's [[Wikiversity:Copyrights|licensing requirements]] (CC BY-SA). * '''Template''': Display the {{tl|AI-generated}} template at the top of pages, or below the description template for files, when the content contains substantial AI-generated material. Contributors wanting to use AI-generated content in ways not covered by this policy should seek community input by discussing at the [[Wikiversity:Colloquium|Colloquium]]. ==See also== ;Meta * [[meta:Artificial intelligence/Policies by project|Artificial intelligence/Policies by project]] (List) ;Wikimedia projects * [[b:Wikibooks:Artificial intelligence|Wikibooks:Artificial intelligence]] (Policy) * [[c:Commons:AI-generated media|Wikimedia Commons:AI-generated media]] (Policy) * [[w:Wikipedia:Large language models|Wikipedia:Large language models]] (Information page) * [[w:Wikipedia:Writing articles with large language models|Writing articles with large language models]] (Guideline) ;Wikiversity project guidelines * [[Motivation and emotion/Assessment/Using generative AI|Using generative AI]] (Motivation and emotion) ==External links== ;Wiki Education Foundation * [https://dashboard.wikiedu.org/training/students/generative-ai Using generative AI tools with Wikipedia] (Training module) [[Category:Artificial intelligence]] GPT-5.4 nano: If your talk-page post is itself AI-generated text, then yes—you should clearly indicate the origin in the edit summary when you post it, and include a publicly accessible link to the chatbot conversation (or a copy of the transcript). If the talk-page post counts as “substantial AI-generated material,” you’d also use the `{{AI-generated}}` template—but that’s mainly for page content, not a short note. Practical minimal approach: when you post, use an edit summary like “AI-generated text (see transcript link)” and include the link/transcript. -------------------- User prompt 13 of 21 - 7/5/2026, 4:11:54 AM: so all I need is the edit summary? on talk pages like this users cannot provide a separate edit summary so I'm assuming at the end we add: Meta: Edit Summary: link here...right? GPT-5.4 nano: On a Wikiversity user talk page, you can’t reliably rely on the “edit summary” field being visible/usable for others, so the usual practical equivalent is to include the AI notice directly in the message text (and/or in the page’s visible metadata if there is one). For your exact policy excerpt, the safest interpretation is: - include an explicit note in the post text that it’s AI-generated, and - include a publicly accessible link to the chatbot conversation or a copy of the transcript. You do **not** add “Meta: Edit Summary:” as separate text unless Wikiversity specifically requires that format; instead, just add a short line like: “AI-generated (chat transcript: …)” with the link/transcript right in your talk-page comment. -------------------- User prompt 14 of 21 - 7/5/2026, 4:13:02 AM: This is the 10 word topic. Can we add it here so we warn all users : "you are reading 100% LLM generated content right now"? Low-pressure request: Would you skim my neurodiversity-inspired idea? GPT-5.4 nano: “AI note: This comment is 100% LLM-generated. Low-pressure request: skim my neurodiversity-inspired idea?” -------------------- User prompt 15 of 21 - 7/5/2026, 4:13:32 AM: This talk page topic is 100% LLM-generated...right? GPT-5.4 nano: I can’t determine whether it’s truly “100% LLM-generated” unless you provide what you wrote vs what was generated. If the text you plan to post is the exact message produced by the LLM, then yes: it is 100% LLM-generated (i.e., the entire message content was generated by the model). -------------------- User prompt 16 of 21 - 7/5/2026, 4:13:49 AM: No, I'm just suggesting what it might say, to be specific... GPT-5.4 nano: Then no—I can’t say it’s “100% LLM-generated” yet. If you copy/paste it exactly as the text produced by the model, it’s 100% LLM-generated; if you wrote or edited it yourself, then it isn’t. -------------------- User prompt 17 of 21 - 7/5/2026, 4:14:20 AM: Ok, maybe we opt for this talk page post contains LLM-generated content? GPT-5.4 nano: Talk page post: “Note: This talk page post contains LLM-generated content.” -------------------- User prompt 18 of 21 - 7/5/2026, 4:15:44 AM: Is this ok if I replace topic with this? "LLM generated content: This talk page post about Neurodiversity draft." GPT-5.4 nano: Yes—just make it grammatical and unambiguous, e.g.: “LLM-generated content: This talk page post is about my neurodiversity draft.” -------------------- User prompt 19 of 21 - 7/5/2026, 4:16:00 AM: 11 words due to adding "is"? GPT-5.4 nano: “LLM-generated content: This talk page post is about my neurodiversity draft.” -------------------- User prompt 20 of 21 - 7/5/2026, 4:16:34 AM: That's 12 words and that's ok. I wanted 9 words but I won't linger on this... GPT-5.4 nano: “LLM-generated content: Talk post about my neurodiversity draft.” -------------------- User prompt 21 of 21 - 7/5/2026, 4:18:32 AM: I put both topic and message in text file: file.txt and it counted 63 words. I'm way below 100! I said what I wanted I think! :) GPT-5.4 nano: Nice—if you’re under 100 words, you’re well within your target. ✅ </nowiki> === Goal: Interact with User:Jtneill at Nov 9, 2026 === Viewing the wiki text will let you see the text in a structured way with linebreaks and proper formatting. <nowiki>This conversation was generated with Duck.ai (https://duck.ai) using OpenAI's GPT-6 Luna Model. AI chats may display inaccurate or offensive information (see https://duckduckgo.com/duckai/privacy-terms for more info). ==================== User prompt 1 of 13 - 11/9/2026, 6:47:06 AM: These are my 2/3 suggestions for a new title for my project on Draft space in Wikiversity when interacting with https://en.wikiversity.org/wiki/User_talk:Jtneill#LLM-generated_content:_Talk_post_about_my_neurodiversity_draft: "Suggestions: 1. "Similarities in Thinking: Systematic Similarities Between People" 2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum"" 3. Do you wanna fill in 3 or ask me questions? This is the draft I was asked about: https://en.wikiversity.org/wiki/Draft:The_Neurodiversity-inspired_Idea This is the URL to the conversation: https://en.wikiversity.org/wiki/User_talk:Jtneill#LLM-generated_content:_Talk_post_about_my_neurodiversity_draft This is what I typed in July: "Hello Jtneill — does the topic I’ve brought up interest you? If so, would you be willing to spend about 5 minutes skimming through my “idea” on Wikiversity (“Draft:The Neurodiversity-inspired Idea”)? No need to overthink it, and I’m not expecting a reply soon—tomorrow, in a month, or even later would all be welcome. Thank you. Metadata: Since edit summaries are not present on talk pages like this one, I'll link to the LLM interaction history that I saved in my Wikiversity user space here: User:ThinkingScience/All_General_AI_Prompt_History_Archive#Goal:_Interact_with_User:Jtneill_at_July_5,_2026 so that I follow Wikiversity:Artificial intelligence. ThinkingScience (discuss • contribs) 04:38, 5 July 2026 (UTC)" This is the reply I got the same month: "Apologies, I've been on leave. I took a 5-second look. My first thought is: Can you name the idea? i.e., rather than calling the page "The Neurodiversity-inspired Idea", which doesn't really say very much, develop a name that describes the idea itself in half a dozen words. -- Jtneill - Talk - c 03:41, 21 July 2026 (UTC)" GPT-6 Luna: I’d fill in **3** rather than ask more questions. Based on the draft’s focus on comparing how people think and identifying shared patterns, a concise option could be: 3. **Comparing Thinking Patterns Across People** That names the idea more directly than “the entire spectrum,” which could suggest the draft covers every form of neurodivergence. Of your first two, **“Similarities in Thinking: Systematic Similarities Between People”** seems closer to the draft’s apparent focus; you might tighten it to **“Shared Patterns in How People Think.”** [1] Read More [1] Neurodiversity Movement/Section 1: The Basics — https://en.wikiversity.org/wiki/Neurodiversity_Movement/Section_1:_The_Basics -------------------- User prompt 2 of 13 - 11/9/2026, 6:49:39 AM: I went with this, I modified your output to this: "Suggestions: 1. "Similarities in Thinking: Systematic Similarities Between People" 2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum" 3. "Neurodiversity Brain Prediction System Across People"" GPT-6 Luna: <!-- **Evaluating feedback response** I need to consider how to respond to the user's feedback. First, I should inspect the links and ensure they accurately reflect current facts. This suggests I’ll need to search through relevant pages to gather the necessary information. It's important to provide a well-informed response, so I'll focus on making sure everything aligns with the facts available. Let's ensure I'm thorough in this process! --> That works as a third option, but **“Neurodiversity Brain Prediction System Across People”** sounds like the project predicts how people’s brains work. If that’s not what you mean, a clearer title might be **“A System for Comparing Thinking Patterns Across People.”** Of the three, I’d favor **“Similarities in Thinking: Systematic Similarities Between People”** if the main idea is finding shared patterns, or the revised title if it’s specifically about a system for comparing them. -------------------- User prompt 3 of 13 - 11/9/2026, 6:50:52 AM: “Neurodiversity Brain Similarity System Across People” What about that? GPT-6 Luna: That’s clearer than **“Brain Prediction System”** because it no longer implies the system predicts people’s brains. But **“Brain Similarity System”** is still a little hard to parse. I’d suggest: **“A System for Comparing Brain Patterns Across People”** If the project is about thinking rather than brains specifically, **“A System for Comparing Thinking Patterns Across People”** may be clearer and less likely to sound like it measures brain activity. -------------------- User prompt 4 of 13 - 11/9/2026, 6:53:08 AM: 1. "Similarities in Thinking: Systematic Similarities Between People" 2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum" 3. "A System for Comparing Thinking Patterns Across People" Thinking Patterns rather than Brain Patterns? GPT-6 Luna: Yes—**“thinking patterns”** is the better fit if your project is about how people think, rather than measurable brain activity. It’s clearer and doesn’t imply you’re studying or comparing people’s brains directly. Of the three, **“A System for Comparing Thinking Patterns Across People”** is the most direct description of the idea, though a little longer than Jtneill’s “half a dozen words” suggestion. A shorter version could be **“Comparing Thinking Patterns Across People.”** -------------------- User prompt 5 of 13 - 11/9/2026, 6:53:39 AM: 1. "Similarities in Thinking: Systematic Similarities Between People" 2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum" 3. "A System for Comparing Brain Patterns Across People" I left it at this. I think we are done? GPT-6 Luna: Yes, that’s a reasonable set to send. One small note: **“Brain Patterns”** can sound like measurable brain activity, while **“Thinking Patterns”** describes thought and cognition more broadly. If the draft is about ideas or ways of thinking, your earlier wording may be more precise; otherwise, you’re ready to leave it as is. -------------------- User prompt 6 of 13 - 11/9/2026, 6:56:03 AM: The system builds on what the Neurodiversity movement is searching for. A better or improved version of "neurotype". Perhaps "sub neurotypes" like what a "neurotype" is made up of...in the parts. 1 person 1 "subneurotype" that explains their specific "neurodivergence" in regards to their brain how it is similar to other people's brain, regardless of if they are diagnosed or not since. Questions on how I expressed this...what I mean? GPT-6 Luna: I think you mean a way to describe **an individual’s particular pattern of neurodivergent traits**—not just assign them a broad neurotype or diagnosis. The system would break that broader profile into more specific components (“subneurotypes”) and use those to describe how one person’s cognitive profile is similar to or different from other people’s, whether or not either person has a diagnosis. A few questions could help pin it down: - Is a **subneurotype** one specific trait or tendency, or a cluster of related traits? - Would each person have one subneurotype, or a unique profile made up of several? - Are you comparing people’s **thinking and behavior**, or making claims about their brains biologically? - Is the goal to describe similarities and differences, help people understand themselves, or suggest new categories that might improve on “neurotype”? - How would the system avoid treating its categories as diagnoses or fixed labels? One possible plain-language summary is: **“A system for describing individual cognitive profiles through smaller patterns of traits, and comparing those patterns across people.”** -------------------- User prompt 7 of 13 - 11/9/2026, 6:58:18 AM: Considering how I've seen "neurotype" being applied...I'd say that's too broad. I go deeper. subneurotype can be applied to a person just as "neurotype" can but a neurotype is general or loosely based on a statistical manual while subneurotype can tell a specific way the brain functions and is related to brain abilities that is much challenging to find, at least in the beginning of this "pilot project". GPT-6 Luna: That clarifies the distinction: **“neurotype”** is a broad, general category, while your proposed **“subneurotype”** would describe a more specific way an individual’s brain functions, including abilities that may be difficult to identify—especially in the pilot stage. You’re aiming to explore those specific patterns rather than simply apply an existing diagnostic or statistical category. A concise description might be: > **A pilot project exploring specific patterns of brain function and ability—“subneurotypes”—that go beyond broad neurotype categories.** One wording point to consider: if the project identifies these patterns through observation or self-report rather than direct measurement of brain activity, **“cognitive patterns and abilities”** may be more precise than **“how the brain functions.”** -------------------- User prompt 8 of 13 - 11/9/2026, 6:59:08 AM: "A pilot project exploring specific patterns of brain function and ability—“subneurotypes”—that go beyond broad neurotype categories." Yes how do we make a half a dozen word title for the project? GPT-6 Luna: **Exploring Individual Subneurotypes and Cognitive Abilities** That’s six words and captures the project’s focus without suggesting the categories are already established. -------------------- User prompt 9 of 13 - 11/9/2026, 7:00:16 AM: Pilot Project: Measuring Individual Subneurotype Differences? GPT-6 Luna: That’s six words and communicates a pilot study, but **“measuring”** may imply you already have a defined, reliable way to quantify subneurotypes. If the project is still exploring and identifying them, **“Pilot Project: Exploring Individual Subneurotype Differences”** is more cautious and still six words. -------------------- User prompt 10 of 13 - 11/9/2026, 7:00:56 AM: replacing pilot project considering that's descriptive of the type...I was just missing two words and can you fill in to my 4 word: "Measuring Individual Subneurotype Differences"? GPT-6 Luna: **Measuring Individual Subneurotype Differences Across People** “Across People” completes the phrase and makes clear that the project compares individuals’ subneurotype differences. -------------------- User prompt 11 of 13 - 11/9/2026, 7:02:59 AM: Suggestions: 1. "Similarities in Thinking: Systematic Similarities Between People" 2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum" 3. "Measuring Individual Subneurotype Differences Across People" So I post this to User_talk:Jtneill's latest reply on -- Jtneill - Talk - c 03:41, 21 July 2026 (UTC) then? GPT-6 Luna: <!-- **Researching user query** I need to provide an answer, but first, it seems wise to check the relevant Wikiversity page. Since the user has asked for some action advice, I should confirm this. So, I'll do a web search for current pages to gather the necessary information. It’s important to make sure I’m basing my response on the latest and most accurate resources. Let’s see what I can find! --> <!-- **Refining response recommendations** I’m thinking about how to respond in a nuanced way. Yes, replying to the latest comment is a good idea, but the title “Measuring Differences” might suggest an operational measure rather than specifying a pattern. I could list options and consider #3 as the strongest, although the term “Neurodiversity Spectrum Explained” might not accurately represent the entire spectrum. Maybe I should suggest adding a framing note. I also need to emphasize that concise titles are best for this experimental draft as it seems like a collaborative effort. --> Yes—reply directly to Jtneill’s July 21 comment with the three options. **“Measuring Individual Subneurotype Differences Across People”** best reflects your current idea, though “measuring” suggests you already have a defined way to measure those differences. If you’re still developing the method, **“Exploring Individual Subneurotype Differences Across People”** may be more accurate. You could add one short note so Jtneill understands what “subneurotype” means in your proposal: > I’m using “subneurotype” to mean a more specific pattern of cognitive functioning or ability within a broader neurotype. Which title best communicates that idea? That gives them a clear question to respond to without making the talk post too long. -------------------- User prompt 12 of 13 - 11/9/2026, 7:04:03 AM: As is without changes...I mean like this: Suggestions: 1. "Similarities in Thinking: Systematic Similarities Between People" 2. "Neurodiversity Spectrum Explained: Description of Entire Spectrum" 3. "Measuring Individual Subneurotype Differences Across People" GPT-6 Luna: Yes—you can post it exactly as written as a list of title suggestions. Just keep in mind that option 3 may lead Jtneill to ask what you mean by **“subneurotype”** or how the differences would be measured. -------------------- User prompt 13 of 13 - 11/9/2026, 7:04:59 AM: More questions the better. They challenge me and motivate me to work harder on developing this. With that said we are done? Time to post? GPT-6 Luna: Yes—time to post it as written. If questions help you develop the project, option 3 is a good one to include because it may invite discussion about what “subneurotype” means and how you’d measure differences.</nowiki> jrj91o245lc0edak0dtgu636pm503px 0 330072 2844928 2844240 2026-11-09T03:25:52Z Jtneill 10242 Copyediting 2844928 wikitext text/x-wiki {{title|Automaticity and goal pursuit:<br>How do habits and environmental cues drive unconscious goal pursuit?}} __TOC__ ==Overview== {{RoundBoxTop|theme=8}} [[File:Driver, Driving the open top sports car, Rostov-on-Don, Russia.jpg|right|thumb|200px|'''Figure 1'''. Undercover officer in pursuit.]] ;Picture this... James is undercover. The air is cold, the night is dark and worst of all... he's tired. James was about to make the arrest when the suspect gets jumpy and decides to book it. He wastes no time going after them, lights flaring and sirens wailing as the tyres of his unmarked police car squeal as he takes off in pursuit. James spots his radio out of the corner of his eye. He grabs it, instantly citing the car make, colour, number plate, location and relevant call signs for support all without a second thought. He's gaining on the suspect but they're still out of reach until he watches their car lurch as they hit a catastrophic downshift, costing them seconds. He can smell the clutch. As they approach the highway, the backup James called for arrives blocking the top of the on-ramp. The suspect gives up, exiting the car with their hands held above their head and their eyes aimed at the ground. A successful arrest with no casualties. As James thinks back on the night with a sense of pride he also finds himself in awe of his performance. He focused solely on maintaining visual of the suspect, but also managed to perform skilled operation of a vehicle, navigation and detailed but brief communication all resulting in incremental advantages lending themselves to the success of the arrest with barely any thought involved. Maybe it was his training? Maybe it was the adrenaline? Regardless of what's true James just can't shake the feeling that everything just felt... automatic. "I'm a machine!" he thinks to himself, in a cool "robocop" kind of way. {{RoundBoxBottom}} Automaticity frees your brain for [https://pmc.ncbi.nlm.nih.gov/articles/PMC8371589/ higher-order thinking], helping you improve your proficiency in goal areas. In fact, many behaviours we perform daily are automatic (see Figure 1). However, it can also drag you down. Many people have behaviours they're unsatisfied with but do anyway, even when it is in conflict with their goals. This is because they have formed habits, and those habits execute themselves automatically in response to stimuli. Understanding how to leverage habit formation is a strong strategy for pursuing goals and making the behaviours that drive them sustainable. Psychological science can help with specific frameworks to engineer the most effective cueing routine to increase the likelihood of taking action toward your goals, hopefully without even thinking about it. {{RoundBoxTop|theme=3}} '''Focus questions''' # How do you develop automatic behaviours? # What do environmental cues contribute? # How can we utilise automaticity in goal pursuit? {{RoundBoxBottom}} ==Automatic behaviour formation== Ever think your friend is weird for getting up at 5 am? Or that James, the undercover police officer is incredibly disciplined for going to the gym after work every day? Well, while those tasks might feel foreign to some people, others do them automatically. These behaviours are formed through repetition, and, with enough repetition, they eventually become automatic. The individual no longer questions "should I go to the gym after work?"; they just go. The famous [[wikipedia:Classical_conditioning|Pavlov's theory of classical conditioning]] explains how two things, seemingly unrelated to each other can become linked to a particular outcome. Classical conditioning involves taking a neutral stimulus and transforming it within the individual to elicit a conditioned response (Sanvictores, et al. 2024): * Neutral stimulus elicits no response (e.g. a bell). * Unconditioned stimulus (e.g. food) elicits a direct response known as the unconditioned response (e.g. salivation). * A conditioned response (e.g. salivating to the bell) happens when the Neutral stimulus creates the same response as the unconditioned stimulus (e.g. salivating) ===Formation factors and dual process=== Wood & Rünger (2016) stated that through repeating context-dependent responses the behaviour strengthens into a habit. These habits become the default and most efficient way to deal with the situation. They go on to describe two factors of habit automaticity, activation by recurring context clues and insensitivity to short term goals which includes changes in response outcomes. In order for someone to change behaviours sufficient motivation is required to tailor themselves to new circumstances. Wood & Rünger (2016) cited dual process theory in their paper as a key theory explaining that habits are the individual engaging in Type 1 thinking. Type 1 thinking being {{g}} automatic behaviour which is less cognitively demanding while Type 2 thinking is reliant on attention and mental resources to execute {{f}}. These habits becoming the new default, and incidentally a Type 1 process {{g}}. This could explain the identified insensitivity to short term goals. Due to the behaviour becoming a Type 1 process it reduces mental friction that would have been incurred by reducing mental resources significantly and making it more favourable in the decision making process. This could become particularly troublesome when dealing with maladaptive behaviours with high levels of automaticity as each repetition against it initially requires attention and planning. ===Automatic behaviour formation in action=== Lally et al. (2010) ran an experiment investigating habit automaticity through volunteers selecting a habit, and a context (e.g. morning walk after breakfast). They measured this through a self-report habit index (SRHI) analysing a history of repetition, automaticity (lack of control and awareness, efficiency), and expressing identity (Verplanken & Orbell, 2003). Participants met 95% of their asymptote of automaticity between 18 and 254 days. The variation could be explained by a lack of consistency during the process, especially early on. Lally et al. (2010) stated that missing occasional opportunities to perform an action did not substantially affect behaviour formation, however, significant early disruption could significantly delay achieving high levels of automaticity as the highest yield improvements to automaticity occur early in the process, with subsequent actions providing less and less improvements the closer they get to the limit of automaticity. Other limiting factors could also be task complexity, personal enjoyment, social support/facilitation and how much the individual identifies with the activity they're doing. Wood & Rünger (2016) provide a explanation on the presence of automaticity in behaviours, being refined over time through consistent context-dependent responses while also explaining the challenges in behaviour change by engaging with Dual Process Theory. Lally et al. (2010) expands on this providing real life evidence of behaviour change through investigating repetitive contextual behaviours and monitoring the process of increasing the automaticity of a behaviour. ;Key takeaways for engaging in behaviour change: * Recognising initial cognitive effort and sufficient motivation are essential for setting expectations. * Missing opportunities to perform the behaviour is okay as long as the behaviour is consistent overall. * The behaviour formation timeline varies significantly {{ic|depending on what?}}. ==Function of environmental cues== Environmental cues function similarly to classical conditioning. Environmental cues can be deliberate, such as sitting at a computer in the university library to promote thoughts of study, or inadvertent, attempting to drive to the shops and accidentally starting to drive to work (Wood & Neal, 2007). In that situation, the environmental cue would be the using a computer in the library environment or driving the same road you take to work. That behaviour becomes a routine that your brain programs to run automatically. Wood & Neal in 2007 called this the habit-goal interface model. They claim that habits are artifacts of previous goal pursuits and that the success of that particular method is ingrained within the body so it can recall it to repeat that success. Their model had two principles: * The power of contexts to trigger habitual responding. * The absence goal mediation in context response associations {{g}}. Patterns arise in life, intentional or otherwise. The first principle {{ic|of what}} {{f}} claims that people store patterns as procedural memory, which, once stored, can be activated by the specific cues associated with that pattern. The second principle claims that goal-oriented behaviours can stick around without thinking about the outcome or if the behaviour is relevant. This is a great insight, as it shows that behaviours can be cognitively offloaded from an internal "willpower" system to an external system. However, it warns against and aims to explain the accidental accumulation of unhelpful behaviours and provide context for their rigidity. ===Environmental cue evidence=== Environmental cues can trigger in an unwanted behaviours too. Neal et al. in 2011 ran an experiment where moviegoers with strong popcorn eating habits and weak popcorn eating habits were assessed on their popcorn consumption during a movie and a campus meeting room. They were presented with both fresh and stale popcorn. Interestingly the moviegoers with strong habits would still continue to eat stale popcorn during the movie regardless of the influence of hunger, but were guided by their personal preferences more when in the meeting room resulting in very little stale popcorn being consumed. The change in location disrupted this process from occuring, but their second study revealed an even more interesting discovery. Consuming the popcorn with their non-dominant hand actually also interrupted the automatic behaviour, {{g}} they did not behave habitually and reduced their consumption of stale popcorn. {{ic|Who were the participants? How many were there? What country? How strong were the observed effects?}} Environmental cues may also reduce neutral or even beneficial habits. Wood et al. (2005) conducted an experiment on {{ic|how many?}} university students {{where}} transferring to a new university. They analysed {{how}} exercise, TV viewing and reading as well as everyday thoughts and actions via two surveys conducted four weeks apart. They revealed that changes in the context of which the behaviours were performed decreased the likelihood they'd perform the rehearsed behaviour. To preserve these behaviours some participants developed decisions about particular behaviours, which caused them to form or retrieve intentions about those behaviours which guided their actions. They concluded that behaviours were only sustained where the context to perform remained unchanged (e.g. reading the newspaper with others) without intervention from behavioural intention. To maintain a behaviour such as going for a run in the park, if there isn't one in proximity they would need to have the intention to continue running in order to adapt the behaviour to a new context, otherwise the behaviour would become extinct. ===Environmental cues example=== Wood and Neal (2007) provides the framework for setting a deliberate behaviour, {{g}} the context needs to be specific to the behaviour. If James, the undercover officer, plays lots of video games on his home PC and occasionally try to do paperwork, the habit to play video games will be stronger and he will find it more difficult to engage in paperwork. This results in a weak plan to change behaviour as his context is more fluid. Strong context would be going to a local library to perform that specific activity. Doing this reduces the likelihood of the issue Neal et al. (2011) studied where unwanted or unpleasant behaviours occurred because the environment triggered their automatic response. If James' {{g}} moves house and no longer lives near the library he will run into the issue Wood et al. (2005) discussed where his behaviour of doing paperwork may deminish because the context cue of doing it at the library is gone. ;Key takeaways for engaging in behaviour change: * Building patterns with intention creates a relatively effortless process over time. *Goal-orientated behaviours can persist even once the goal has been achieved, without intentionally wanting to achieve the goal or without the goal being relevant. *Behaviours triggered by environmental cues can be negative in the wrong context. *Lack of presence in environmental cues can reduce the likelihood those behaviours will be performed or even maintained. ==Pursuing goals with automaticity== Goal pursuit is always envisioned with a strong conscious effort. Overcoming trials and adversity requires steadfast courage and an unbreakable will. So the idea that it could be an unconscious effort seems to go against everything pursuit would stand for. However, cueing the desired behaviour removes decision-making, which is arguably where most people get stuck. Pursuing goals through automaticity aims to remove decision-making around taking action. In the opening scenario, James, the undercover police officer had multiple opportunities to freeze or question their actions. Because of training-specific cues, they activated lights and sirens, identified key information about the suspect, and relayed it with the appropriate callsign without hesitation. This lack of decision-making freed up mental capacity to give chase and achieve the goal of a successful arrest. Wood & Rünger (2016) state that habits interface with goal pursuit in three ways: '''Exposure''', '''activation or inhibition''' and '''inference'''. # '''Exposure''' provides context cues. During training, James, the undercover officer would practise the same behaviours in response to the same stimulus repeatedly. Eventually, the habits become linked to context cues, ready for activation or inhibition. # '''Activation and inhibition''' allow the cue to activate or inhibit a behaviour immediately. Suspect flees --> Lights and sirens go up --> Radio relevant information. Behavioural activation increases the likelihood of a particular behaviour occurring, often requiring conscious thought to intervene during execution rather than before. # '''Inference''' is observing your own behaviour and determining whether it aligns with your goals. James would be guided by their objective to apprehend the suspect safely. Lights and sirens increase safety, radioing important information increases the chance of finding them if they escape, and calling for backup increases the odds of making an arrest. James might associate that doing all of the above makes him a good police officer because those are things a good officer would do, which is in line with his goal of being a good officer. Gollwitzer and Sheeran (2006) conducted a meta-analysis to understand the effectiveness of pursuing goals with automaticity and what aids in the process. {{g}} Literature they looked at previously suggested that the strength of intention was a defining factor, however, the reason for their meta-analysis was what conflicting literature said about intention. Intention was deemed insufficient by other researchers, resulting in them using the quote "the road to hell is paved with good intentions". They found that independant tests showed that implementation intentions (a plan of the when, where and how) produced a medium-to-large positive effect on goal attainment. ===Pursuing goals in context=== Wood & Rünger (2016) sets up the a way to engage with Gollwitzer and Sheeran's (2006) findings in order to construct a plan to maximise success. First determine a goal, this information should aim to pair with the ideal '''inference''' about the behaviour. Next is the '''activation and inhibition''' stage, {{g}} create the implementation intentions of when and where specific behaviours should occur or not occur. Finally plan out the '''exposure''' stage, this introduces the how {{g}} Here cues need to be selected to trigger the activation or inhibition of a specific behaviour in context. James would set a goal to be a good officer. Then determine that lights, sirens, communication and attention to detail are valuable actions he wants to perform. Then {{g}} would plan for the context cue to be the suspect fleeing. This way when James starts pursuing a fleeing suspect, {{g}} once rehearsed, these behaviours will activate automatically. <quiz display=simple> {Behaving in the best interest of your goal is ______: |type="()"} + Inference - Activation - Inhibition - Exposure {Activation and inhibition allow _________: |type="()"} - You to turn a behaviour on or off at your own command. + Environmental cues to activate a learned behaviour. - Priming of the brain to consider action - Environmental cues to be maintained in the brain. </quiz> ===Subconscious pursuit=== Autonomous means something is automatic, but the discussion so far has been exclusively on controlling this automatic process which by extension starts to sound manual. However, subconscious pursuit of goals is a very real topic, lying below all assumed control listed above and otherwise. Goals do not require a conscious choice, the environment and those around can cue specific goals to be pursued {{g}}. Bargh et al. (2001) conducted a series of five experiments testing whether or not they could subconsciously influence peoples {{g}} goals in particular tasks. They conducted a series of priming effects over each experiment designed to subconsciously plant goals (e.g. a crossword with motivational words vs a crossword with random unrelated words). They found across each experiment that subconscious goal pursuit meaningfully influenced performance when completing the tasks laid out before them. However they also established that subconscious pursuit did not require a specific conscious goal beforehand to be performed. Task 2, a resource allocation task, was left open for interpretation for the treatment group and still produced meaningful positive change in the outcome {{explain}}. Subconscious pursuit might be hard to manipulate for the sake of improving goal pursuit, {{g}} it can activate goals outside of conscious choice and may influence the execution of related behaviours in context to the task. This suggests subconscious goals still, while not an entire alternative, still {{g}} have a degree of strength and that conscious thinking does not paint the full picture. ==Conclusion== Utilising current {{what}} theory it is possible to manufacture meaningful and viable ways to achieve goals through environmental cueing. Practical use has been discussed extensively during this book chapter providing insight into the processes we can engage in to improve our own goal seeking behaviour through context specific cueing {{vague}} {{explain}}. It is important to also be flexible with the expectations of using automaticity through environmental cues to improve goal pursuit as it can take anywhere from 18 to 254 days to properly form the desired automatic behaviours. One significant benefit users can hope to see is a reduction in cognitive load over time which is encouraging because it tells the user that their initial struggle to perform the task will lessen which should reinforce the behaviour. It is also important to consider when behaviours might be cued negatively (e.g. Neal and colleagues {{g}} stale popcorn experiment in 2011) to avoid unwanted behavioural cuing. Loss of behavioural cues can cause behavioural decay which be used positively to remove unwanted behaviours but is important to consider when you're trying to maintain specific behaviours under environmental change. Wood et al.'s (2016) model of exposure, activation and inhibition, and inference represents the ways in which habits interact with goal pursuit. These provide multiple avenues for individuals to try to prompt themselves to produce the best results they can when pursuing a goal. And to wrap up, not every goal is conscious. Some goals simply exist below the surface and automatically improve the tasks we engage in or inform us to behave in a way we are not consciously aware of. ==See also== {{expand}} ==References== {{Hanging indent|1= Bargh, J. A., Gollwitzer, P. M., Lee-Chai, A., Barndollar, K., & Trötschel, R. (2001). The Automated Will: Nonconscious Activation and Pursuit of Behavioral Goals. ''Journal of Personality and Social Psychology'', ''81''(6), 1014–1027. https://doi.org/10.1037/0022-3514.81.6.1014 Gollwitzer, P. M., & Sheeran, P. (2006). Implementation Intentions and Goal Achievement: A Meta‐analysis of Effects and Processes. In M. P. Zanna (Ed.), ''Advances in Experimental Social Psychology'' (Vol. 38, pp. 69–119). Elsevier Science & Technology. https://doi.org/10.1016/S0065-2601(06)38002-1 Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W., & Wardle, J. (2010). How are habits formed: Modelling habit formation in the real world. ''European Journal of Social Psychology'', ''40''(6), 998–1009. https://doi.org/10.1002/ejsp.674 Sanvictores, T., Mahabadi, N., & Rehman, C. I. (2024). ''Classical conditioning.'' StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK470326/ Verplanken, B., & Orbell, S. (2003). Self-Report Habit Index (SRHI) [Database record]. ''APA PsycTests.'' https://doi.org/10.1037/t03772-000 Wood, W., & Neal, D. T. (2007). A New Look at Habits and the Habit-Goal Interface. ''Psychological Review'', ''114''(4), 843–863. https://doi.org/10.1037/0033-295X.114.4.843 Wood, W., & Rünger, D. (2016). Psychology of Habit. ''Annual Review of Psychology'', ''67''(1), 289–314. https://doi.org/10.1146/annurev-psych-122414-033417 Wood, W., Tam, L., & Witt, M. G. (2005). Changing Circumstances, Disrupting Habits. ''Journal of Personality and Social Psychology'', ''88''(6), 918–933. https://doi.org/10.1037/0022-3514.88.6.918 }} ==External links== * Clumsy effort to effortless action - [https://www.youtube.com/watch?v=eiBn0tbzHRM YouTube] * How habits guide behaviour with Wendy Wood - [https://www.youtube.com/watch?v=OWiDYOjgEFI YouTube] * Implementation intentions - [https://www.youtube.com/watch?v=mbGjJpkIsWM YouTube] * Wendy Wood's publication page - [https://dornsife.usc.edu/wendy-wood/publication/ External Website] [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Behaviour]] [[Category:Motivation and emotion/Book/Goal striving]] [[Category:Motivation and emotion/Book/Habit]] [[Category:Motivation and emotion/Book/Unconscious]] qji4usoy64f1lrsp1kz2hgezmj5xvw2 10 330232 2844908 2844851 2026-11-08T23:13:22Z Jtneill 10242 2844908 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. 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Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors).## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> fzrsibwbds95wo6tskqklp0zleyxumt 2844921 2844908 2026-11-09T01:14:26Z Jtneill 10242 # The scenario does not sufficiently illustrate the topic 2844921 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. Designed to be [[Help:Transclusion|transcluded]] on a chapter [[Help:Talk page|talk page]]. __NOTOC__</noinclude><includeonly> ==[[Motivation and emotion/Assessment/Chapter|Book chapter]] review and feedback== {{RoundBoxTop|theme=8}} This chapter has been reviewed according to the [[Motivation and emotion/Assessment/Chapter/Marking criteria|marking criteria]]. Written feedback is provided below, plus there is a [[Motivation and emotion/Assessment/Chapter/Feedback|general feedback]] page. Please also check the chapter's [[Help:Page history|page history]] to check for editing changes made whilst reviewing through the chapter. Chapter marks will be available via {{Motivation and emotion/Canvas}} along with [[Motivation and emotion/Assessment/Social contribution|social contribution]] marks and feedback. Keep an eye on Announcements. {{RoundBoxBottom}} {{RoundBoxTop|theme=}}[[File:Wikiuutiset logo typewriter.png|right|85px]] ===Overall=== {{{1|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Overview (5%)|Overview]]=== {{{2|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Theory (20%)|Theory]]=== {{{3|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Research (25%)|Research]]=== {{{4|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Integration (10%)|Integration]]=== {{{5|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Conclusion (5%)|Conclusion]]=== {{{6|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Style (20%)|Style]]=== {{{7|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Learning features (5%)|Learning features]]=== {{{8|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Social contribution (10%)|Social contribution]]=== {{{9|No comment}}} {{RoundBoxBottom}}</includeonly><noinclude>{{collapse top|Simple example}} ==Simple example== See also [[#Detailed example|detailed example]] <pre> <!-- Official feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} ~~~~ </pre> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) {{Collapse bottom}} ==Detailed example== Example use of the template, with some common feedback comments: <small><small><small><pre> <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors).## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> c6wdjl2xwho62u703fwy9f8ub19riqk 2844922 2844921 2026-11-09T01:18:31Z Jtneill 10242 # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons 2844922 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. Designed to be [[Help:Transclusion|transcluded]] on a chapter [[Help:Talk page|talk page]]. __NOTOC__</noinclude><includeonly> ==[[Motivation and emotion/Assessment/Chapter|Book chapter]] review and feedback== {{RoundBoxTop|theme=8}} This chapter has been reviewed according to the [[Motivation and emotion/Assessment/Chapter/Marking criteria|marking criteria]]. Written feedback is provided below, plus there is a [[Motivation and emotion/Assessment/Chapter/Feedback|general feedback]] page. Please also check the chapter's [[Help:Page history|page history]] to check for editing changes made whilst reviewing through the chapter. Chapter marks will be available via {{Motivation and emotion/Canvas}} along with [[Motivation and emotion/Assessment/Social contribution|social contribution]] marks and feedback. Keep an eye on Announcements. {{RoundBoxBottom}} {{RoundBoxTop|theme=}}[[File:Wikiuutiset logo typewriter.png|right|85px]] ===Overall=== {{{1|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Overview (5%)|Overview]]=== {{{2|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Theory (20%)|Theory]]=== {{{3|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Research (25%)|Research]]=== {{{4|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Integration (10%)|Integration]]=== {{{5|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Conclusion (5%)|Conclusion]]=== {{{6|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Style (20%)|Style]]=== {{{7|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Learning features (5%)|Learning features]]=== {{{8|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Social contribution (10%)|Social contribution]]=== {{{9|No comment}}} {{RoundBoxBottom}}</includeonly><noinclude>{{collapse top|Simple example}} ==Simple example== See also [[#Detailed example|detailed example]] <pre> <!-- Official feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} ~~~~ </pre> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) {{Collapse bottom}} ==Detailed example== Example use of the template, with some common feedback comments: <small><small><small><pre> <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors).## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> fomde8p0eqe6gmskxn9giav7cu7sj48 2844923 2844922 2026-11-09T02:10:07Z Jtneill 10242 2844923 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. Designed to be [[Help:Transclusion|transcluded]] on a chapter [[Help:Talk page|talk page]]. __NOTOC__</noinclude><includeonly> ==[[Motivation and emotion/Assessment/Chapter|Book chapter]] review and feedback== {{RoundBoxTop|theme=8}} This chapter has been reviewed according to the [[Motivation and emotion/Assessment/Chapter/Marking criteria|marking criteria]]. Written feedback is provided below, plus there is a [[Motivation and emotion/Assessment/Chapter/Feedback|general feedback]] page. Please also check the chapter's [[Help:Page history|page history]] to check for editing changes made whilst reviewing through the chapter. Chapter marks will be available via {{Motivation and emotion/Canvas}} along with [[Motivation and emotion/Assessment/Social contribution|social contribution]] marks and feedback. Keep an eye on Announcements. {{RoundBoxBottom}} {{RoundBoxTop|theme=}}[[File:Wikiuutiset logo typewriter.png|right|85px]] ===Overall=== {{{1|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Overview (5%)|Overview]]=== {{{2|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Theory (20%)|Theory]]=== {{{3|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Research (25%)|Research]]=== {{{4|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Integration (10%)|Integration]]=== {{{5|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Conclusion (5%)|Conclusion]]=== {{{6|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Style (20%)|Style]]=== {{{7|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Learning features (5%)|Learning features]]=== {{{8|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Social contribution (10%)|Social contribution]]=== {{{9|No comment}}} {{RoundBoxBottom}}</includeonly><noinclude>{{collapse top|Simple example}} ==Simple example== See also [[#Detailed example|detailed example]] <pre> <!-- Official feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} ~~~~ </pre> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) {{Collapse bottom}} ==Detailed example== Example use of the template, with some common feedback comments: <small><small><small><pre> <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors).## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> 3epwtet21jon632jyh12pu8k40w1877 2844927 2844923 2026-11-09T03:11:46Z Jtneill 10242 2844927 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. Designed to be [[Help:Transclusion|transcluded]] on a chapter [[Help:Talk page|talk page]]. __NOTOC__</noinclude><includeonly> ==[[Motivation and emotion/Assessment/Chapter|Book chapter]] review and feedback== {{RoundBoxTop|theme=8}} This chapter has been reviewed according to the [[Motivation and emotion/Assessment/Chapter/Marking criteria|marking criteria]]. Written feedback is provided below, plus there is a [[Motivation and emotion/Assessment/Chapter/Feedback|general feedback]] page. Please also check the chapter's [[Help:Page history|page history]] to check for editing changes made whilst reviewing through the chapter. Chapter marks will be available via {{Motivation and emotion/Canvas}} along with [[Motivation and emotion/Assessment/Social contribution|social contribution]] marks and feedback. Keep an eye on Announcements. {{RoundBoxBottom}} {{RoundBoxTop|theme=}}[[File:Wikiuutiset logo typewriter.png|right|85px]] ===Overall=== {{{1|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Overview (5%)|Overview]]=== {{{2|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Theory (20%)|Theory]]=== {{{3|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Research (25%)|Research]]=== {{{4|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Integration (10%)|Integration]]=== {{{5|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Conclusion (5%)|Conclusion]]=== {{{6|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Style (20%)|Style]]=== {{{7|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Learning features (5%)|Learning features]]=== {{{8|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Social contribution (10%)|Social contribution]]=== {{{9|No comment}}} {{RoundBoxBottom}}</includeonly><noinclude>{{collapse top|Simple example}} ==Simple example== See also [[#Detailed example|detailed example]] <pre> <!-- Official feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} ~~~~ </pre> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) {{Collapse bottom}} ==Detailed example== Example use of the template, with some common feedback comments: <small><small><small><pre> <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Include a relevant image # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors).## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> bmf4fi1px14hjj4gf4jmlmmessnmppd 2844934 2844927 2026-11-09T06:19:43Z Jtneill 10242 2844934 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. Designed to be [[Help:Transclusion|transcluded]] on a chapter [[Help:Talk page|talk page]]. __NOTOC__</noinclude><includeonly> ==[[Motivation and emotion/Assessment/Chapter|Book chapter]] review and feedback== {{RoundBoxTop|theme=8}} This chapter has been reviewed according to the [[Motivation and emotion/Assessment/Chapter/Marking criteria|marking criteria]]. Written feedback is provided below, plus there is a [[Motivation and emotion/Assessment/Chapter/Feedback|general feedback]] page. Please also check the chapter's [[Help:Page history|page history]] to check for editing changes made whilst reviewing through the chapter. Chapter marks will be available via {{Motivation and emotion/Canvas}} along with [[Motivation and emotion/Assessment/Social contribution|social contribution]] marks and feedback. Keep an eye on Announcements. {{RoundBoxBottom}} {{RoundBoxTop|theme=}}[[File:Wikiuutiset logo typewriter.png|right|85px]] ===Overall=== {{{1|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Overview (5%)|Overview]]=== {{{2|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Theory (20%)|Theory]]=== {{{3|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Research (25%)|Research]]=== {{{4|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Integration (10%)|Integration]]=== {{{5|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Conclusion (5%)|Conclusion]]=== {{{6|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Style (20%)|Style]]=== {{{7|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Learning features (5%)|Learning features]]=== {{{8|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Social contribution (10%)|Social contribution]]=== {{{9|No comment}}} {{RoundBoxBottom}}</includeonly><noinclude>{{collapse top|Simple example}} ==Simple example== See also [[#Detailed example|detailed example]] <pre> <!-- Official feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} ~~~~ </pre> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) {{Collapse bottom}} ==Detailed example== Example use of the template, with some common feedback comments: <small><small><small><pre> <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons # Include an image that illustrates the scenario/case study <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons # Include an image that illustrates the scenario/case study <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Remove [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors).## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> 84vk4e3zhhlzpkn8ldvhdm8nd7ytexh 2844941 2844934 2026-11-09T07:02:34Z Jtneill 10242 2844941 wikitext text/x-wiki <noinclude>Feedback [[wikiversity:FAQ/Template|template]] for the [[Motivation and emotion/Assessment/Chapter|book chapter]] exercise for the [[motivation and emotion]] unit. Designed to be [[Help:Transclusion|transcluded]] on a chapter [[Help:Talk page|talk page]]. __NOTOC__</noinclude><includeonly> ==[[Motivation and emotion/Assessment/Chapter|Book chapter]] review and feedback== {{RoundBoxTop|theme=8}} This chapter has been reviewed according to the [[Motivation and emotion/Assessment/Chapter/Marking criteria|marking criteria]]. Written feedback is provided below, plus there is a [[Motivation and emotion/Assessment/Chapter/Feedback|general feedback]] page. Please also check the chapter's [[Help:Page history|page history]] to check for editing changes made whilst reviewing through the chapter. Chapter marks will be available via {{Motivation and emotion/Canvas}} along with [[Motivation and emotion/Assessment/Social contribution|social contribution]] marks and feedback. Keep an eye on Announcements. {{RoundBoxBottom}} {{RoundBoxTop|theme=}}[[File:Wikiuutiset logo typewriter.png|right|85px]] ===Overall=== {{{1|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Overview (5%)|Overview]]=== {{{2|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Theory (20%)|Theory]]=== {{{3|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Research (25%)|Research]]=== {{{4|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Integration (10%)|Integration]]=== {{{5|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Conclusion (5%)|Conclusion]]=== {{{6|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Style (20%)|Style]]=== {{{7|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Learning features (5%)|Learning features]]=== {{{8|No comment}}} ===[[Motivation and emotion/Assessment/Chapter/Marking criteria#Social contribution (10%)|Social contribution]]=== {{{9|No comment}}} {{RoundBoxBottom}}</includeonly><noinclude>{{collapse top|Simple example}} ==Simple example== See also [[#Detailed example|detailed example]] <pre> <!-- Official feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} ~~~~ </pre> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # |2= <!-- Overview comments... --> # |3= <!-- Theory comments... --> # |4= <!-- Research comments... --> # |5= <!-- Integration comments... --> # |6= <!-- Conclusion comments... --> # |7= <!-- Style comments... --> # |8= <!-- Learning features comments... --> # |9= <!-- Social contribution comments... --> # }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) {{Collapse bottom}} ==Detailed example== Example use of the template, with some common feedback comments: <small><small><small><pre> <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons # Include an image that illustrates the scenario/case study <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Reduce use of [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Check and correct use of [https://www.google.com.au/search?q=affect+vs.+effect+grammar affect vs. effect] ## Check and correct use of [http://www.colonsemicolon.com/ semicolons (;) and colons (:)] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Overuse of the present perfect: use the simple past tense consistently when reporting previous research e.g., ### Present perfect: "Chivers (2010) has also suggested ..." ### Simple past: "Chivers (2010) suggested ..." <!-- Style – Abbreviations --> ## Abbreviations ### Only use abbreviations such as e.g., i.e., et al., etc. inside [[w:Bracket#Parentheses|parentheses]], otherwise spell them out ### Check and correct formatting of abbreviations (such as e.g., i.e., etc.) ### Use abbreviations sparingly. Do not use abbreviations for minor/infrequently used terms. ### Explain abbreviations on first use: Spell out each abbreviation when it first appears (e.g., self-determination theory (SDT)), to ensure readers understand the term before its subsequent use ### Once an abbreviation has been established (e.g., PTSD), use it consistently afterwards ### Only introduce abbreviations which are subsequently used <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) ## Some words are misspelt (e.g., see the {{sp}} tags). Spell-checking tools are available in most internet browsers and word processing software packages. <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). ## Remove unnecessary capitalisation – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## "Use quotation marks only for the first occurrence of the word or phrase, not for subsequent occurrences" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) ## Direct quotes need page numbers—even better, communicate about concepts in your own words ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Very well/Well/Reasonably well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation). ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Figures - Other --> ### Some image uploads were removed because of a lack of sufficient/appropriate copyright information ### Numbering needs correcting ### Adjust some image sizes to make them easier to read (increase size) and/or less dominant (decrease size) <!-- Style – Tables --> ## Table(s) ### Very well/Well/Reasonably well captioned ### Brief caption(s); provide more explanatory detail about the table ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) ### The source(s) of the information presented in one or more tables needs acknowledgement <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style ### Each Table is referred to at least once within the main text ### Refer to each Table using APA style (e.g., do not use bold, italics, check and correct capitalisation) ### Refer to each Table at least once within the main text (e.g., see Table 1) <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # Citations use very good/good/reasonably good/basic/poor [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some/many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## List multiple citations in alphabetical order by first author surname (e.g., Giraffe, 2024; Zebra & Aardvark, 2020) ## A full stop is needed after "et al" (i.e., "et al.") because it is an abbreviation of [[wikt:et alii|et alii]] ## Use a comma between the author(s) and year for citations in [[w:Bracket#Parentheses|parentheses]] ## Select up to a maximum of three citations per point (i.e., avoid citing four or more citations to support a single point) ## Check and correct placement of full-stops ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois ## Move embedded links to non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section; only cite peer-reviewed sources # For citations, use APA style or wiki style, but not both # Secondary citations are overused; strive to consult primary sources <!-- Style – References --> ## References use excellent APA style ## References use very good/good/reasonably good/basic/poor APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Separate page numbers using an [[w:Dash#En dash|en dash]] (–) rather than a hyphen (-) ### Include dois where available ### Hyperlink dois for 1-click access ### Provide the full titles of journals ### Remove "Retrieved from " ### Use alphabetical order ### Move Wikipedia links into the [[{{PAGENAME}}#See also|See also]] section ### Move non-peer reviewed sources into the [[{{PAGENAME}}#External links|External links]] section ### Remove bullet-points; add hanging indent ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles # Very good/Good/Reasonably good/Basic/One use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} ~~~~ </pre></small></small></small> gives <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an outstanding chapter that successfully integrates psychological theory and research in a highly readable way to address a practical, real-world phenomenon or problem # This is an excellent chapter that successfully uses psychological theory and research to address a practical, real-world phenomenon or problem # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # This is a good chapter that makes good use of psychological theory and research to address a real-world phenomenon or problem # This is a reasonably good chapter that makes OK use of psychological theory and research to address a real-world phenomenon or problem # This is a basic chapter # This is an insufficient chapter # The main area(s) for potential improvement: #* use the best psychological theory about the topic #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* tackle the target topic more directly; this chapter [[wikt:beat around the bush|beats around the bush]] #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* express more in your own words—overuse of direct quotes and/or unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # Excellent use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in most or all of the main edits # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for most edits, but would ideally be more descriptive and extensive # The edit history is quite brief, showing limited development # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of academic, peer-reviewed citations to support claims # Only cite sources that you consult # All citations need to be in the References <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [ these cop yedits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study # Reasonably good scenario or case study; could be more compelling # Basic scenario or case study # The written expression for the scenario needs improvement to be of a professional standard # Use a more practical, real-life scenario; move review of research into a subsequent section # Use an example that a wider audience can relate to; less than 5% of the world population are university students # The scenario does not sufficiently illustrate the topic # Add an engaging case study or scenario <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # Figure 1 could be more relevant to the scenario # Figure 1 lacks relevance to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Figure 1 was poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons # Include an image that illustrates the scenario/case study <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Explains the psychological problem or phenomenon reasonably well/in a basic way # Briefly explains the psychological problem or phenomenon; provide more detail # Description of problem is too long or vague or overly complicated—explain the psychological problem or phenomenon in a simpler way. Move detail into subsequent sections. # Insufficient explanation of the psychological problem or phenomenon # Clarity of written expression can be improved # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) # The focus questions are very good/good/reasonably good/basic/promising/insufficient # The focus questions could be improved by: ## being more specific to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## splitting double-barrelled questions into separate questions ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) # Add focus questions in a feature box # See copy edits for examples of possible improvements |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied # Very good—key theories are well explained and applied; minor areas for improvements # Good—key theories are quite well explained and applied; minor to moderate areas for improvements # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # Basic—a basic range of relevant theories are selected, described, and explained; there is considerable room for improvement # A promising range of ideas are presented but it is far from clear how this material is derived from a first person reading of the best peer-reviewed psychological theory and research about this topic # Insufficient use of relevant psychological theory about this topic # Reduce general theoretical background (e.g., definitions). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds effectively on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds reasonably well on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds somewhat on other [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds in a basic way on [[w:|Wikipedia]] articles and/or/but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Build more strongly on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful/Very good/Good/Reasonably good/Basic/Insufficient depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Excellent/Very good use of tables, figures, and/or lists to clearly convey key theoretical information # Good/Reasonably good/Basic/Insufficient/No use of tables, figures, and/or lists to convey key theoretical information # The sources(s) of information presented in tables lacks sufficient citation <!-- Theory – Citations --> # Key citations are well used # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) # If you didn't consult an original source (e.g., ?), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] # If you didn't consult an original source, don't cite it <!-- Theory – Examples --> # Excellent/Very good/Good/Reasonably good/Basic use of examples to illustrate theoretical concepts # Consider using more examples to illustrate theoretical concepts # Use more examples to illustrate theoretical concepts # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # More recent research would be ideal # Claims are well referenced # In some/many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. # Insufficient use of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Research – Critical thinking --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient integration between the most relevant theory(ies) and the best research # Basic, formulaic # The chapter places more emphasis on theory than on research; strive for an integrated balance # Rather than describing individual studies separately, synthesise findings across related studies to identify common themes, patterns, and differences in the evidence # The chapter could be strengthened through deeper integration with related [[Motivation and emotion/Book|chapters]] by including more embedded links # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Excellent/Very good/Good/Reasonably good/Basic summary and conclusion # Insufficient as a cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Is this section based on [[Motivation and emotion/Assessment/Using generative AI|genAI output]]? If so, this was not acknowledged in the [[Motivation and emotion/Wikiversity/Edit summary|edit summary]]. # Highlights the importance of the problem or phenomenon of interest # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # The focus questions are addressed # Take-away messages for each focus question could be spelt out more clearly # Address the focus questions <!-- Conclusion – Take-home messages --> # Clear take-home message(s) # Somewhat clear take-home message(s) # Add practical, take-home message(s) <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is excellent/very good/good/reasonably good/basic ## The quality of written expression is reasonably good, but appears to be based on overuse of insufficiently acknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] ## The quality of written expression is OK but there are several aspects which are below professional standard ## The quality of written expression is below professional standard. [https://www.canberra.edu.au/current-students/study-skills UC Study Skills] assistance is recommended to help improve writing skills. ### GenAI is over-used; write more in your own words, based on your own knowledge based on reading the primary sources ## Use active (e.g., "this chapter explores" or "this chapter explored") rather than passive voice (e.g., "this chapter will explore" or "this chapter has explored") [https://apastyle.apa.org/style-grammar-guidelines/grammar/active-passive-voice][https://www.grammarly.com/blog/active-vs-passive-voice/] ## Target an ''international'' rather than domestic national audience. [http://www.worldometers.info/world-population/australia-population/ Only 0.3% of the world human population lives in Australia]. ## Reduce excessive use of bold font <!-- Style – Sentences --> ## Some/Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression ## Some/Many sentences are overly long. Strive for the simplest expression. Consider splitting longer sentences into two shorter sentences. Shorter words and sentences are more [[w:Readability|readable]]. Try conducting a readability analysis such as via https://www.webfx.com/tools/read-able/. This chapter gets a score of . Aim for 50+. ## Avoid starting sentences with a citation unless the author is particularly pertinent. Instead, it is more interesting for the the content/key point to be communicated, with the citation included along the way or, more typically, in [[w:Bracket#Parentheses|parentheses]] at the end of the sentence. <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. ## Bullet points are overused. Use full sentences and paragraphs. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st of 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Embed direct quotes within sentences and paragraphs, rather than presenting them [[wikt:holus-bolus|holus-bolus]] ## "Individuals" is overused. "People" is usually a clearer term than "individuals". Use ''individuals'' to highlight each person separately (e.g., “individual test scores”) and ''people'' when referring to humans more generally. ## Reduce use of [[w:weasel words|weasel words]]—they add bulk without improving meaning ## Use permanent, rather than relative, time references. For example, instead of "20 years ago", refer to something like "at the beginning of the 21st century". In this way, the text will survive better into the future, without needing to be rewritten. ## Avoid overly emotive language (e.g,. *) in science-based communication <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## The structure is overly complicated; simplify and integrate ## The structure is overly complicated; aim for 3 to 6 top-level headings between the Introduction and Conclusion ## The chapter structure is underdeveloped; expand by using subheadings ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## Use the default heading style (e.g., remove additional numbers, italics, bo]ld, and/or change in font size) ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Move links from headings into their first mention in text ## Remove abbreviations/citations from headings ## Include an introductory paragraph before branching into the sub-sections ## Integrate research rather than having it as a stand-alone section(s) ## Integrate (embed) learning features such as quizzes, without their own headings, rather than having them as stand-alone sections ## The Overview and Conclusion should not have subheadings (fixed) ## Remove colons (:) from the ends of headings <!-- Style – Grammar --> # Grammar and spelling are excellent # Grammar ## The grammar for some/many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. 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Adding more interwiki links for the first mention of key words and technical concepts would make the text even more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. # Use [[m:Help:Interwiki linking|interwiki links]] (rather than external links) to Wikipedia articles, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Internal link style --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Excellent use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]] # Very good/Good/Reasonably good/Basic/One use of embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. # Use in-text [[m:Help:Interwiki linking|interwiki links]], rather than external links to Wikiversity chapters, per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of figure(s) # Excellent/Very good/Good/Reasonably good/Basic/No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Excellent/Very good/Good/Reasonably good/Basic use of scenarios, case studies, or examples # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Excellent/Very good/Good/Reasonably good/Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Make the quiz questions more interactive by using the [[Help:Quiz|quiz]] feature # The reflection questions could be made more interactive by using a drop-down box that the reader can expand to see an answer/prompt to figure out the answers to the questions (e.g., see [[Motivation and emotion/Book/2026/Immersive therapy for PTSD treatment|this chapter]]) # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use internal linking style per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move peer-reviewed articles into the [[{{PAGENAME}}#References|References]] section and cite ## Move external links into the [[{{PAGENAME}}#References|External links]] section ## Add more links # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient/No use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Use bullet points per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Rename links per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## Use [https://www.masterclass.com/articles/sentence-case-explained sentence casing] ## Use alphabetical order ## Include sources in [[w:Bracket#Parentheses|parentheses]] after the link ## Move Wikipedia/Wikiversity links to the [[{{PAGENAME}}#See also|See also]] section ## Move peer-reviewed articles to the [[{{PAGENAME}}#References|References]] section and cite ## Target an international audience ## Add more links ## Link to the top 3-6 external resources about this topic # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~ logged, useful, mostly minor/moderate/major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~ logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons uploads # Thanks very much for your extensive contributions # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:47, 10 October 2026 (UTC) ==See also== * [[Motivation and emotion/Assessment/Chapter|Book chapter guidelines]] * [[Template:METF]] * [[Template:MEMF]] [[Category:Motivation and emotion/Admin/2026]] [[Category:Motivation and emotion/Assessment/Chapter]] </noinclude> 9v1q3eogz3i9tas2lof1wj6fkoocl0a 0 330494 2844940 2844722 2026-11-09T06:40:28Z ~2026-46935-18 3110252 /* */ 2844940 wikitext text/x-wiki <big>The John Snow prediabetes Institute is an international research network focused on early identification of prediabetes, prehypertension and other types of metabolic syndrome in the early ages for lifestyle health promotion. (https://w.wiki/Skm7)</big> <big>'''Background:''' Millions of people are at an increased risk of developing metabolic syndrome, starting with atherosclerosis, pre-diabetes, pre-hypertension, hypertension, and being overweight before the age of 30, often without symptoms.[1] These conditions constitute the background for developing type 2 diabetes mellitus, cardiovascular diseases (CVDs), which are the leading cause of death and disability worldwide. Early prevention is possible, and a cost-effective preventive strategy can improve long-term health outcomes. '''Prevalence studies''' are used to identify high-risk groups, in schools, professionals, nurses, and medical students for targeted prevention. Alternatively to clinical testing, the high risk groups are identified by re-analyse the data, in the age-groups to identify the demographic root causes. For prevention, different strategies are used, as example the</big> <big>16-weeks '''intervention studies, with''' learning by video sequences and self-monitoring of blood sugar with glukometer and self-evaluation of diet and physical activity <ref>https://www.sciencedirect.com/science/article/abs/pii/S1751991825001068 </ref>. The newest, challenging intervention studies are the AI-Digital lifestyle programs.<ref> «Digital Lifestyle Program Cuts Diabetes Risk by 46% in Prediabetics, Study of 130k+ Adults Reveals». News-Medical, 14 de abril de 2025. https://www.news-medical.net/news/20250414/Digital-lifestyle-program-cuts-diabetes-risk-by-4625-in-prediabetics-study-of-130k2b-adults-reveals.aspx.</ref> Educational material is available from the international diabetes organisations e.g ADA:<ref>https://professional.diabetes.org/diabetes-support-resources</ref> and the Health Promoting Schools.<ref> https://www.dropbox.com/scl/fi/0rm7honrezbjwrcy3h3yk/Health-promoting-schools.docx?cloud_editor=word&dl=0&rlkey=673jyzcmwbfw7k9ui9nmtp0zh </ref></big>[[File:Lifestyle Medicine Pillars.png|250px|right| <big>Lifestyle Medicine Pillars.png The focus of Lifestyle Medicine is on these 6 pillars</big> ]]'''<big>Prevalence studies</big>''' [[/The Maritime Health database design // |<big>1.1 The Maritime Health database design</big>]] <big>1.2 Nursing Students Health Database <ref> https://www.dropbox.com/scl/fi/tcznmmd2y3nona5e3h1ro/The-Nursing-students-health-database.docx?cloud_editor=word&dl=0&rlkey=onbjh4o8ko1lzdvgyi8nlrotk </ref></big> <big>1.3. Medical student's Health Database <ref>https://www.dropbox.com/scl/fi/f16h9b60u4gxgt56un2jf/The-Medical-students-Health-database.docx?cloud_editor=word&dl=0&rlkey=xyfqen5trdc5lniaovipl548n </ref></big> <big>1.4. School childrens` Health database <ref> https://www.dropbox.com/scl/fi/u6u50c8bxwhte9t2t6ck8/The-School-children-s-Health-database.docx?cloud_editor=word&dl=0&rlkey=zlyz5wn673wf7owettq3nx3h5 </ref></big> <big>1.5 Excel recoding of the clinical data (pre diabetes, hypertension etc) <ref>https://www.dropbox.com/scl/fi/9qvqeccto2kbuqvx7mdkl?r=ACsntb2AuiFkJbEBLObVdo0HMD67UZBBUGCGl1RPCPy1X5Y3K3e9Lf4s7cG7i7E_iH0IK-WkynXw_FNCDWybHuCgaNl_OM8yche2w2aapJGk5BTHybbsLpLayBU8VKPPqxNa2zDaNslBdQg0MhmKTFSG</ref></big> <big>'''Personal prevention''' Personal reversal of prediabetes relies on targeted lifestyle changes like eating a healthy diet, exercising regularly, and losing a modest amount of excess weight. (local Diabetes Associations)</big> <span lang="en" dir="ltr"><big>'''Core Institutional Strategies''' Health authorities and organizations implement group-based or digital programs. The workplaces are prompted to make targeted interventions, including nutrition and exercise programs, to safeguard long-term cardiometabolic health in the workforces.</big></span> <big>16 weeks human caused Intervention studies: English <ref>https://www.dropbox.com/scl/fi/oi6cx6tlwwvoko3ed37tn/Invitation-to-the-course-English.docx?cloud_editor=word&dl=0&rlkey=7kzg91tqfgjskxf5aji8khicx </ref> Danish <ref>https://www.dropbox.com/scl/fi/2qahc3q9hmf4skbvk77ab/Invitation-to-the-course-in-Danish.docx?cloud_editor=word&dl=0&rlkey=x63w8oqvarz284zg2btq2johv </ref> Spanish <ref> https://www.dropbox.com/scl/fi/bn71inqeeth4o4mc1fjth/Invitation-to-the-course-Spanish.docx?cloud_editor=word&dl=0&rlkey=popmr1fnodh1v951v9l7k9ezv </ref> and '''AI-Powered Lifestyle Intervention''' in the Diabetes Prevention <ref>Mathioudakis, Nestoras, Benjamin Lalani, Mohammed S. Abusamaan, et al. «An AI-Powered Lifestyle Intervention vs Human Coaching in the Diabetes Prevention Program: A Randomized Clinical Trial». JAMA 334, n.º 23 (2025): 2079-89. https://doi.org/10.1001/jama.2025.19563.</ref></big> '''<big>Organisation</big>''' <big>- [[/The John Snow Institute bylaws /|The John Snow Institute bylaws]]</big> <big>- General research protocol draft <ref> https://www.dropbox.com/scl/fi/gau25oy5y1s57046icjt2/Research-protocol-draft.docx?cloud_editor=word&dl=0&rlkey=wat63e25ritmujwcpss8s4v0s </ref></big> <big>- Health Promoting Schools <ref> https://www.dropbox.com/scl/fi/0rm7honrezbjwrcy3h3yk/Health-promoting-schools.docx?cloud_editor=word&dl=0&rlkey=673jyzcmwbfw7k9ui9nmtp0zh </ref></big> [[Category:Prediabetes ]] [[Category:Prediabetes ]] <big>'''Publications''' <ref name=":0"> https://www.dropbox.com/scl/fi/mw7ft423lkkpjoxywd2bf </ref></big> '''The John Snow Prediabetes Institute Research Network:''' <small>Prof. Dr. Olaf Jensen, MD, MPH, PhD; Prof. Ing. MSc. Nailet Delgado Mujica; Prof. Magda Medir Mb, Tarragona Spain, Prof. MSc.Ph.D. Bishal Gyawali SDU; MSc.PhD Vivi Just-Nørregaard; Prof. Dr. Johan Hviid Andersen MD, PhD. Århus University; Prof. MSc. Agnes Flores, UMECIT, Panama; Bruno Nørdam, Randers; Maritime Doctor. Erik Haarløv MD, Assens, Denmark; Dr. Maite Duque MD Venezuela; Dr. Indira Santos Panama MD; Med.Stud. Ashley Lezcano, Panama; Dr. Joseph Abesamis MD Filippines; Dr. Jen Mendoza, MD, Filippines; Dra.Marj Gab Huerte, MD, Filippines:</small> <small>Dr. Andra Ergle MD, Latvia; Prof. MSc. Ingrid Morató, Tarragona and Cadiz, Spain; Dr. Alejandro Martinez, MD, MPH, Costa Rica; Christian Acheampong, MBA, New Jersey US; Dr. Med. Sci Finn Gyntelberg NFA.and Bispebj. Hosp. Denmark: Dr. Solomon Ching MD Filippines: Dr. Marcel Alcaraz MD Filippines;</small> ==References== 391viz92xc6jbebliws60vi6ccf2cbl 0 331530 2844964 2843836 2026-11-09T11:37:38Z Jtneill 10242 Minor additions to the Book Chapter feedback 2844964 wikitext text/x-wiki {{title|Trust rebuilding after trauma:<br>How can trauma survivors develop trust in similar situations again?}} __TOC__ ==Overview== {{RoundBoxTop|theme=3}} [[File:Sad Teen Girl Portrait.jpg|thumb|200x200px|'''Figure 1'''. Even years after trauma, the fear of being hurt can remain]] ;Scenario Imagine a girl named Zara, who experienced a traumatic event several years ago with an ex-boyfriend. This event is very much over, however, Zara continues to feel unsafe and insecure in relationships. When she meets a new boy she likes, she worries they are angry or that she's done something wrong, if they take a little while to respond to her messages. She often struggles to be vulnerable with these people and avoids communicating her feelings for fear of judgement and abandonment. Zara has recently made a new friend at college, someone who is incredibly kind, communicates openly, and doesn't make her second-guess. Despite these consistent, kind behaviours, Zara finds it difficult to believe that person will never hurt her. {{ic|Consider adjusting the scenario to more clearly address the topic which is about rebuilding trust}} {{RoundBoxBottom}} [[w:Trust (social science|Trust]] is crucial to the success, fulfilment, and longevity of romantic relationships. Trust isn't a single emotion or choice, but a vital concept built on intimacy, love, respect, and care. However, trust can be broken. In this chapter, we discuss how trauma survivors can develop their trust again in similar situations, while learning to accept the emotional responses that may be brought up from previous traumatic experiences. The following points explain the importance and psychological theories that can assist in understanding these processes.   * A lack of trust negatively impacts a relationship, causing interpersonal problems through lying and anxiety * Within monogamous relationships, emotional and physical infidelity is the most common experience that destroys trust with partners. * Betrayal trauma leads to trauma responses, in many instances, causing great emotion and psychological damage.* Rebuilding trust is crucial to relationship recovery and health. * Psychological science provides several perspectives that can explain the process of rebuilding trust in trauma survivors. * This research and theory includes: Attachment theory and betrayal trauma theory {{RoundBoxTop|theme=3}} ;Focus questions {{ic|Use bullet points as shown in Tutorial 2}} 1. How can experiences of betrayal trauma disrupt trust and influence future relationships? 2. Why do trauma survivors experience distrust in new situations that correspond with the original traumatic experience? 3. How can trauma survivors rebuild trust through new relationship experiences? {{RoundBoxBottom}} == How Does Betrayal Trauma Affect Future Relationships? == Trauma can arise from an extremely distressing or disturbing experience and has lasting effects on an individual's psychological health (Das & Jain, 2024). These traumatic experiences contribute to many psychological impacts, with symptoms of anxiety and depression, difficulties with trust, and disruptions to personal connections (Freyd et al., 2005). Betrayal trauma is the experience when a person or institution that an individual trusts violates that trust, leading to severe psychological harm (Freyd, 1994). When betrayal occurs within a romantic relationship, it can influence how they approach intimacy, trust, and reliability in future romantic relationships {{f}}. === Understanding Betrayal Trauma === Freyd's (1994) betrayal trauma theory suggests that the psychological impact of betrayal depends on the relationship between the person who experiences the harm and the person responsible for it. The theory suggests that when someone relies on a person who betrays them, it may be difficult to recognise the betrayal (Das & Jain, 2024). Betrayal trauma assists in explaining the emotional hurt an individual is affected by after their trust and wellbeing are violated by significant people in their life (Freyd, 1994). Partner infidelity or “cheating” is a form of interpersonal trauma, which causes PTSD, depression and anxiety in 30% to 60% of betrayed people {{f}}. The act of intimate betrayal causes a traumatic memory. Clinically, this combination of symptoms points toward a stress-related disorder (Lonergan et al., 2020). An act of betrayal between romantic partners is one that harms a shared set of core beliefs established in the relationship and destroys the ability to have a partner as a source of safety and comfort (Lonergan et al., 2020). In romantic relationships, infidelity may challenge a victim's ability to trust their partner but also the expectations they established of honesty and reliability {{f}}. Understanding the psychological impacts of partner betrayal provides insights into how trust can be affected in future relationships. === Betrayal Trauma and Interpersonal Trust === According to the betrayal trauma theory {{f}}, individuals are susceptible to developing betrayal blindness when they are unable to fully recognise betrayal by someone they trust. In a relationship, betrayal blindness can be severely impactful {{f}}. Difficulty recognising betrayal can affect an individual's ability to judge someone's trustworthiness and leave them more vulnerable to being hurt in future relationships (Gobin & Freyd, 2014). Zurbriggen and Freyd (2004) suggest that traumatic betrayals damage the cognitive functions that enable individuals to judge a person's trustworthiness, which could lead them to trust unworthy people and increase the chances of future betrayal. Supporting this theory, Gobin and Freyd (2009) discovered {{how}} that victims {{where}} of high betrayal trauma (HBT) had an increased likelihood of staying in a romantic relationship after experiencing infidelity and a betrayal of trust. Gobin and Freyd (2014) conducted an experiment investigating the relationship between betrayal trauma and interpersonal trust by examining their {{who}} participants' trust in others, their romantic partners, and their behaviours in an experimental trust game. They discovered that participants who reported HBT also reported having lower trust in romantic partners. Following infidelity, victims may be hesitant and show caution when trusting future partners, because they don't wish to experience betrayal again. However, developing trust may involve not only learning to trust romantic partners in future relationships but also regaining confidence in their own judgement of others. [[File:Figure 2. Jennifer J. Freyd's Two-Dimensional Model for Traumatic Events.png|309x309px]] Jennifer J. Freyd's Two-Dimensional Model for Traumatic Events === Attachment and Intimacy after Betrayal === Interpersonal trauma has been shown to influence attachment styles, with a dependency on the attachment between the victim and the perpetrator (Brennan et al., 1998, as cited in Das & Jain, 2024). Although attachment theory was originally developed to explain relationships between children and their caregivers, researchers have since applied it to romantic relationships (Das & Jain, 2024). Attachment theory emphasises human beings' natural tendency to form and maintain loving, caring, and affectionate bonds with others. (Bowlby, 1988 as cited in Mosley, 2022). In a romantic relationship, secure attachment is associated with emotional security, physical closeness, and a reciprocal sense of safety between partners. However, betrayal by a romantic partner threatens relationship safety and security, resulting in an attachment injury, a violation of trust that affects a victim's beliefs about the relationship (Johnson et al., 2001, as cited in Mosley, 2022). Research suggests that the more intimate the relationship in which the betrayal occurs, the more likely it is to create traumatic memories that affect a person's attachment (Butler et al., 2021, as cited in Mosley, 2022). This has devastating consequences, not only psychologically and physically, because a victim might also struggle to feel confident in another person's trustworthiness as a result. Further impacting how they approach trust and future romantic relationships. == How Does Betrayal Trauma Affect Well-being? == Betrayal trauma impacts the psychological and physiological health of betrayal trauma victims by increasing fear and stress in future relationships. Research links betrayal trauma with difficulties in emotional regulation and mental illness symptoms associated with PTSD, depression and dissociation (Mosley, 2022; Ward, 2026). === Physical and Emotional Responses === In recent history, trauma responses performed by a victim have been associated with feelings of fear during and after the traumatic experience {{f}}. When we experience trauma, our body and brain's primary reaction is fear, triggering a range of physiological and emotional responses (DePrince et al., 2011). In the context of betrayal, the emotional reaction can be described as similar to the emotions people feel when confronted with death or horrific events (Mosley, 2022). Research suggests that emotional regulation capacities are impacted among survivors of Betrayal trauma, with great impacts towards psychological and physiological functioning (Mosley, 2022). Continuous exposure to relationship problems has been shown to disrupt stress regulation systems, with the prefrontal cortex and limbic reactivity most affected {{f}}. Evidence from trauma and stress research supports the likelihood of neurobiological dysregulation in individuals experiencing relationship betrayal (Ward, 2026). Clinical studies have further observed a change in emotional regulation and impaired executive functioning after continuous betrayal is experienced (Ward, 2026). There are also great physical consequences as a result of experiencing betrayal trauma. Our bodies' autonomic nervous system works within nanoseconds, activating to prepare for threats. Our bodies are built to detect danger by increasing adrenaline and cortisol, which prepare us to fight, flee, or shut down (Sutherland, 2019, as cited in Ward, 2026). However, the body works by continuously returning to equilibrium, responding rapidly to stress, and then relaxing {{f}}. Victims of betrayal, as a result of heightened stress, experience an unhealthy state of emotional threat and danger {{f}}. López Martínez et al. (2018, as cited in Ward, 2026) found that the body's continual response to betrayal, and a heightened sense of dread about future betrayals, creates emotional dysregulation by keeping the response system persistently engaged. Researchers have also discovered that victims of high betrayal trauma are more susceptible to experiencing pain in the form of soft tissue, chronic fatigue, diabetes, bladder issues, pelvic pain and asthma (Silber, 2020). === Post-traumatic stress disorder and Mental Illness === PTSD, or post-traumatic stress disorder, is a mental illness most noticeably caused by previous traumatic experiences, characterised by symptoms of depression, alcohol and drug abuse, dissociative tendencies, personality disorders and health concerns (Bremner, 2006). Betrayal trauma has been associated with multiple psychological diagnoses. These include PTSD, depression and dissociation (Mosley, 2022). Through a variety of studies, betrayal trauma was further associated with symptoms of PTSD, being impacted by intrusive thoughts and an impairment in self-concept (Ward, 2026). Atlas and Ingram (1998, as cited in Freyd et al., 2005) reported a stronger association between betrayal trauma and PTSD than between non-betrayal trauma and PTSD. Further research conducted by Kelley (2009, as cited in DePrince et al., 2011) discovered that insights of betrayal had a stronger association with PTSD than perceptions of life threat. Furthermore, Kaehler and Freyd (2009, DePrince et al., 2011) found an association between middle and high levels of betrayal trauma exposure and borderline personality characteristics among a college student population. == How Can Trauma Survivors Rebuild Trust and Feel Safe in Future Relationships? == Rebuilding trust after infidelity is a gradual process which takes time and emphasises the importance for consistent honest, behaviour and support {{f}}. Counselling, forgiveness and managing painful memories can work towards rebuilding trust (Abrahamson et al., 2012). However recovery is dependant on the victims {{g}} decision about whether they will continue with the relationship. === Rebuilding Trust and Emotional Safety === Although infidelity is a severely damaging event, not all couples choose to end their relationship after discovering an affair (Abrahamson et al., 2012). Trust in a relationship involves accepting a degree of vulnerability in relation to expectations of monogamy shaped by a partner's intentions and behaviour (Rousseau et al., 1998, as cited in Pramudito & Minza, 2021). Infidelity damages these expectations, causing the betrayed partner to lose confidence in their partner's honesty and reliability (Pramudito & Minza, 2021). Rebuilding trust is a gradual process that requires more than forgiveness. Olson, Russell, Higgins-Kessler, and Miller (2002, as cited in Abrahamson et al., 2012) describe a three-phase step to rebuilding trust. The first phase is known as the roller coaster phase, describing the continual change or “roller coaster” of emotions. This can be seen in the initial shock, strong feelings of disclosure, and the many uncontrollable emotions that come up. The second phase, known as the moratorium phase, begins when the couple agrees to set  hurt aside and move forward with their lives. Lastly, the third phase suggests the couple look to the future and focus on rebuilding trust in the relationship. Abrahamson et al. (2012) identified that forgiveness, counselling, managing painful memories of the infidelity, and changes in that relationship are all steps towards rebuilding that trust. In addition, Anderson (2025) suggested that viewing infidelity through a trauma-based perspective may assist marriage counsellors to better recognise and assist clients' experiences and provide further evidence-based support. Furthermore, Pramudito and Minza (2021) emphasised the importance of restoring trust over time through consistent demonstrations of faithfulness and honest behaviour. However, more importantly, the perspectives of the betrayed partner are necessary, as it is their decision to remain within the relationship in order to learn to rebuild trust again (Mitchell et al., 2025). However, Mitchell et al. (2025) explains that the betrayed partner may feel pressure to forgive in order for the relationship to continue, and this responsibility, along with overwhelming, ever-changing emotions, can affect their ability to make accurate, necessary decisions about the relationship. To rebuild the victim's trust in the perpetrator, signs of faithfulness and integrity are crucial. Goldie (2013, as cited in Pramudito and Minza, 2021). Furthermore, there is an emphasis on resolving conflicts positively in order to rebuild the victim's trust and to rebuild trustworthiness to work towards building a fully recovered marital relationship (Baucom et al., 2009, as cited in Pramudito & Minza, 2021; Dickie, 2015, as cited in Pramudito & Minza, 2021). {{ic|Use the [[Help:Quiz]] quiz tool}} '''According to the betrayal trauma theory, why can betrayal from a trusted partner make it more difficult in the future to trust another partner?''' {| class="wikitable" |+ ! colspan="3" valign="top" |Quiz 1 - Multiple Choice |- ! valign="top" |A | valign="top" |It makes them dislike their parents and all their friends | rowspan="4" |Answer (B) |- ! valign="top" |B | valign="top" |It ruins their trust, safety, and judgement of whether others are trustworthy |- ! valign="top" |C | valign="top" |It makes them unable to communicate with people |- ! valign="top" |D | valign="top" |It makes them sad |} '''Zara was cheated on by her ex-boyfriend. It's a few years later now and she has a new boyfriend. They are both incredibly happy. However, as the days go by, and not to his fault, she becomes more noticeable of the small changes in her partners behaviours as they develop their relationship. One day he forgets to message her while he's at work. Even though it was a mistake she still feels like something is wrong. What is she experiencing?''' {| class="wikitable" |+ ! colspan="3" valign="top" |'''Quiz 2 - Multiple Choice''' |- ! valign="top" |A | valign="top" |Confidence, in herself and her boyfriend | rowspan="4" |Answer (C) |- ! valign="top" |B | valign="top" |Fatigue, she has had a very long day |- ! valign="top" |C | valign="top" |Hypervigilance, she is highly alert to supposed danger |- ! valign="top" |D | valign="top" |Brain fog, she forgets what has happened |} == Conclusion == Experiences of betrayal, especially those within romantic relationships, are can {{g}} be traumatic and have lasting impacts on a victim's sense of trust and emotional safety in the people around them. Betrayal trauma theory assists in explaining how harm caused by a trusted person can impact beliefs about relationships, while attachment theory assists us in understanding how these experiences may affect intimacy and emotional security. However, the difficulties victims face do not mean they are incapable of developing trust in relationships again. Rebuilding trust is a gradual process in which we learn to recognise signs of trustworthiness and develop confidence in our ability to judge others' trustworthiness. Relationships are built on communication, reliability, safety, and honesty, and experiencing this in a new relationship may build a greater sense of safety. Attempting to recover after infidelity will take time, trust will take time to fully restore, and forgiveness will continue to develop. However, rebuilding trust is not about guaranteeing that betrayal will ever happen again, but is about learning to recognise trustworthiness and to adopt a sense of security that will help victims form meaningful connections despite past hurt. ==See also== Wikipedia Link - PTSD <ref>{{Cite journal|date=2026-09-05|title=Post-traumatic stress disorder in children and adolescents|url=https://en.wikipedia.org/w/index.php?title=Post-traumatic_stress_disorder_in_children_and_adolescents&oldid=1373411231|journal=Wikipedia|language=en}}</ref> Discusses PTSD in children and adolescents and the diagnosis, risk factors, trauma and symptoms. [https://en.wikipedia.org/wiki/Post-traumatic_stress_disorder_in_children_and_adolescents] Wikiversity Link – Trauma and Attachment Development <ref>{{Cite web|url=https://en.wikiversity.org/wiki/Motivation_and_emotion/Book/2025/Trauma_and_attachment_development|title=Motivation and emotion/Book/2025/Trauma and attachment development - Wikiversity|website=en.wikiversity.org|language=en|access-date=2026-10-11}}</ref> Discusses various attachment styles and trauma and the way they both interconnect.[https://en.wikipedia.org/wiki/Post-traumatic_stress_disorder_in_children_and_adolescents] ==References== {{Hanging indent|1= Abrahamson, I., Hussain, R., Khan, A., & Schofield, M. J. (2012, October 21). ''What helps couples rebuild their relationship after infidelity?'' SAGE Publications. ResearchGate. https://www.researchgate.net/publication/233341758_What_Helps_Couples_Rebuild_Their_Relationship_After_Infidelity Affair Recovery. (2021, July 1). ''How to rebuild trust after infidelity: Become reliable'' [Video]. YouTube. https://www.youtube.com/watch?v=k8foEEWnsFw Anderson, M. (2025). The impact and connection between infidelity and PTSD. ''Journal of Counseling Sexology and Sexual Wellness'', ''6''(2). [https://digitalcommons.unf.edu/jcssw/vol6/iss2/ https://doi.org/10.34296/06022017] Bremner, J. D. (2006). Traumatic stress: Effects on the brain. ''Dialogues in Clinical Neuroscience'', ''8''(4), 445–461. [https://www.tandfonline.com/doi/full/10.31887/DCNS.2006.8.4/jbremner https://doi.org/10.31887/dcns.2006.8.4/jbremner] Das, M., & Jain, N. (2024). Partner Betrayal Trauma and trust: Understanding the impact on attachment style and self-esteem. ''European Journal of Trauma & Dissociation'', ''8''(2), 100409–100409. [https://www.sciencedirect.com/science/article/abs/pii/S2468749924000334?via%3Dihub https://doi.org/10.1016/j.ejtd.2024.100409] DePrince, A. P., Brown, L. S., Cheit, R. E., Freyd, J. J., Gold, S. N., Pezdek, K., & Quina, K. (2011). Motivated forgetting and misremembering: Perspectives from betrayal trauma theory. ''Nebraska Symposium on Motivation'', 193–242. [https://link.springer.com/chapter/10.1007/978-1-4614-1195-6_7 https://doi.org/10.1007/978-1-4614-1195-6_7] Ford, J. D, & Courtois, C. A. (2016). ''Treating complex traumatic stress disorders in children and adolescents : Scientific foundations and therapeutic models''. New York ; London The Guilford Press. https://books.google.com.au/books?hl=en&lr=&id=Uv0E4W3bMYcC&oi=fnd&pg=PA62&dq=betrayal+trauma+theory+1996&ots=cKuxJAUZUq&sig=-k98_BIIGp4gzPyPBcidj1WZ-qI#v=onepage&q=betrayal%20trauma%20theory%201996&f=false Freyd, J. J. (1994). Betrayal trauma: Traumatic amnesia as an adaptive response to childhood abuse. ''Ethics & Behavior'', ''4''(4), 307–329. [https://www.tandfonline.com/doi/abs/10.1207/s15327019eb0404_1 https://doi.org/10.1207/s15327019eb0404_1] Freyd, J. J. (2013). ''Definition of Betrayal Trauma Theory''. Uoregon.Edu. https://dynamic.uoregon.edu/jjf/defineBT.html Freyd, J. J., Klest, B., & Allard, C. B. (2005). Betrayal trauma: Relationship to physical health, psychological distress, and a written disclosure intervention. ''Journal of Trauma & Dissociation'', ''6''(3), 83–104. [https://www.tandfonline.com/doi/abs/10.1300/J229v06n03_04 https://doi.org/10.1300/j229v06n03_04] Gobin, R. L., & Freyd, J. J. (2009). Betrayal and revictimization: Preliminary findings. ''Psychological Trauma: Theory, Research, Practice, and Policy'', ''1''(3), 242–257. [https://psycnet.apa.org/doiLanding?doi=10.1037%2Fa0017469 https://doi.org/10.1037/a0017469] Gobin, R. L., & Freyd, J. J. (2014). The impact of betrayal trauma on the tendency to trust. ''Psychological Trauma: Theory, Research, Practice, and Policy'', ''6''(5), 505–511. [https://psycnet.apa.org/doiLanding?doi=10.1037%2Fa0032452 https://doi.org/10.1037/a0032452] Lonergan, M., Brunet, A., Rivest‐Beauregard, M., & Groleau, D. (2020). Is romantic partner betrayal a form of traumatic experience? A qualitative study. ''Stress and Health'', ''37''(1), 19–31. [https://onlinelibrary.wiley.com/doi/10.1002/smi.2968 https://doi.org/10.1002/smi.2968] Martin, C. G., Cromer, L. D., DePrince, A. P., & Freyd, J. J. (2013). The role of cumulative trauma, betrayal, and appraisals in understanding trauma symptomatology. ''Psychological Trauma: Theory, Research, Practice, and Policy'', ''5''(2), 110–118. https://doi.org/10.1037/a0025686 Mitchell, E. A., Brown, K. S., Spencer, J., & Harris, K. (2025). Staying together after infidelity: An exploration of the decision-making process of recovery from the perspective of the injured partner. ''Journal of Marital and Family Therapy'', ''52''(1), e70110. PubMed Central. [https://onlinelibrary.wiley.com/doi/10.1111/jmft.70110 https://doi.org/10.1111/jmft.70110] Mosley, T. L. (2022). ''Forever imprinted: Understanding the relationship between betrayal trauma within intimate relationships and attachment - ProQuest''. Proquest.Com. https://www.proquest.com/openview/c437e8a57b6e9a35babbdda9171ccee0/1?pq-origsite=gscholar&cbl=18750&diss=y Pramudito, A. A., & Minza, W. M. (2021). The dynamics of rebuilding trust and trustworthiness in marital relationship post infidelity disclosure. ''Jurnal Psikologi'', ''48''(2), 16. [https://eprints.ukmc.ac.id/6452/5/Published%20-%20The%20Dynamics%20of%20Rebuilding%20Trust%20and%20Trustworthiness%20in%20Marital%20Relationship%20Post%20Infidelity%20Disclosure.pdf https://doi.org/10.22146/jpsi.60974] Silber, D. (2020). ''Trust again'' (pp. 1–229). Rowman & Littlefield Publishers. https://books.google.com.au/books?hl=en&lr=&id=Yq_uDwAAQBAJ&oi=fnd&pg=PR7&dq=How+can+betrayal+trauma+survivors+develop+trust+in+similar+situations+again%3F&ots=qPVXjqErDK&sig=MZhvi-7EBgNXJXGcfQrj4abtJ60&redir_esc=y#v=onepage&q&f=false Ward, R. (2026). Serial infidelity and psychological abuse: Diagnostic blind spots in recognising betrayal trauma. ''The International Journal of Psychiatry in Medicine''. [https://journals.sagepub.com/doi/10.1177/00912174261428855 https://doi.org/10.1177/00912174261428855] Zurbriggen, E. L., & Freyd, J. J. (2004). The link between childhood sexual abuse and risky sexual behavior: The role of dissociative tendencies, information-processing effects, and consensual sex decision mechanisms. In E. L. Zurbriggen & J. J. Freyd, ''From child sexual abuse to adult sexual risk: Trauma, revictimization, and intervention'' (pp. pp. 135–157). https://pages.uoregon.edu/dynamic/jjf/articles/zf2004.pdf }} ==External links== [https://www.youtube.com/watch?v=5TUxH2izTGI Infidelity: to stay or go?] (Lucy Beresford, TEDX) [https://www.youtube.com/watch?v=k8foEEWnsFw How to Rebuild Trust After Infidelity] (Samuel from Affair Recovery) [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Trauma]] [[Category:Motivation and emotion/Book/Trust]] av48niaxt2ru71rilp53afcjza3zioq 0 331572 2844960 2840618 2026-11-09T10:52:52Z Jtneill 10242 Copyediting 2844960 wikitext text/x-wiki {{title|Boredom and interest:<br>How do boredom and interest shape emotional and motivational states?}} __TOC__ ==Overview== {{RoundBoxTop|theme=5}} [[File:Student in Library Pittsburg State University.jpg|thumb|180px|'''Figure 1'''. Cognitive engagement shifts dramatically depending on whether a learning task triggers state boredom or state interest.]] ; Case scenario: The tale of two study tasks Megan sits in the campus library preparing for an upcoming cognitive psychology examination. After twenty minutes of reading abstract, repetitive definitions of perceptual thresholds and psychophysical scaling, a heavy lethargy sets in: Megan repeatedly checks the clock, opens short-form social media videos, and experiences an aversive feeling of physical and mental restlessness. Later that evening, Megan switches to an interactive computer simulation analysing real-world flight simulator data and cognitive load thresholds; suddenly, Megan experiences heightened alertness, voluntary concentration, and loses all track of time (see Figure 1). Both tasks require intense cognitive exertion, yet one produces paralysing disengagement while the other elicits effortless immersion. What psychological mechanisms explain how identical emotional appraisals transform identical cognitive demands into either profound boredom or energised interest? {{RoundBoxBottom}} This chapter explores the psychological science of [[wikipedia:Boredom|boredom]] and [[Motivation and emotion/Book/2021/Interest|interest]], drawing on appraisal theories, the control-value framework, and the Meaning and Attentional Components (MAC) model to explain how these emotional states regulate [[motivation]], [[wikipedia:Attention|attention]], and goal-directed behaviour. State boredom functions as an aversive state characterised by low arousal and attentional disruption, whereas state interest acts as an approach-oriented emotion fostering intrinsic motivation. Both serve as critical self-regulatory indicators signalling when activities lack subjective value or optimal challenge. {{RoundBoxTop|theme=2}} '''Focus questions''' * How are boredom and interest defined, classified, and operationalised in cognitive and affective psychological science? * What cognitive appraisal processes and neurobiological networks mediate the transition between boredom and interest? * How do the control-value theory and the Meaning and Attentional Components (MAC) model explain the motivational outcomes of these emotional states? * What individual differences (e.g., boredom proneness, trait curiosity) influence vulnerability to boredom and the capacity for interest? * How can students, educators, and professionals implement psychological interventions to convert state boredom into productive situational and individual interest? {{RoundBoxBottom}} == Conceptualising boredom: Definitions, typologies and functions == Boredom is a pervasive yet historically under-researched aversive emotional state defined by an inability to engage attention in satisfying activity, accompanied by distorted time perception and an urgent desire to escape the immediate setting. Far from being a simple lack of things to do, psychological science conceptualises boredom as a complex, multi-dimensional affective and cognitive phenomenon that serves vital self-regulatory functions while carrying significant vulnerability risks when chronic. {{f}} === '''Attentional and phenomenological characteristics''' === State boredom is primarily characterised as an attentional failure where individuals find themselves unable to direct cognitive focus toward internal thoughts or external tasks, while remaining acutely and painfully aware of this inability (Eastwood et al., 2012). Phenomenologically, boredom possesses distinct qualitative signatures, most notably "time drag", the subjective, distorted perception that time is passing unusually slowly, coupled with a restless, agitated desire for alternative stimulation {{f}}. Researchers emphasise the critical need to distinguish state boredom from related affective states: unlike apathy, which is marked by complete emotional indifference and flat affect, boredom involves an active, frustrated yearning for engagement{{f}}. Similarly, while depression involves persistent sadness, feelings of worthlessness, and generalised anhedonia across all life domains, state boredom is typically tied to specific situational contexts or tasks where meaning or optimal challenge is absent (Danckert et al., 2018; Eastwood et al., 2012). === '''Multidimensional typologies of boredom''' === Challenging the historical assumption that boredom is a uniform, flat state of low arousal, contemporary experience sampling methodology (ESM) reveals that boredom manifests in several distinct phenomenological subtypes differentiated by their underlying valence and physiological activation (Goetz et al., 2014). These subtypes capture the diverse ways individuals experience and react to unengaging environments {{f}}: * Indifferent boredom: A relaxed, low-arousal state with minimal affect where individuals drift comfortably. * Apathetic boredom: A distressing, low-arousal state marked by total withdrawal and helplessness. * Calibrating boredom: A mild-arousal state featuring wandering daydreams and openness to distraction. * Searching boredom: An active, restless state driven by the goal-directed pursuit of alternative stimulation. * Reactant boredom: A high-arousal, aversive state prompting urgent urges to rebel against constraints. === '''Functional and evolutionary perspectives''' === Trimmed {{huh}}: Evolutionary perspectives conceptualise boredom as an adaptive "stop signal" (Bench & Lench, 2013). When energetic costs outweigh benefits, boredom signals this mismatch to motivate task switching or environmental modification (Danckert et al., 2018). == The psychology of interest: Appraisal structure and developmental phases == Interest operates as a counter-regulatory epistemic emotion that facilitates learning, exploration, and the acquisition of complex competencies. Silvia's (2005, 2008) cognitive appraisal model demonstrates that interest is elicited by evaluations of novelty-complexity and coping potential. The primary appraisal evaluates whether an event or stimulus is novel, complex, ambiguous, or unexpected, while the secondary appraisal assesses personal coping potential, the subjective evaluation of whether one possesses the cognitive capacity and resources to comprehend and master the novel stimulus. Expanding beyond immediate state appraisals, Hidi and Renninger (2006) traced the evolution {{how}} from transient environmental stimulation to enduring personal interest across four distinct phases. Phase 1 (Triggered Situational Interest) is externally elicited by surprising or vivid features, whereas Phase 2 (Maintained Situational Interest) involves sustained task engagement supported by meaningful learning activities. Phase 3 (Emerging Individual Interest) and Phase 4 (Well-Developed Individual Interest) are internally generated, characterised by stored knowledge, deep personal value, and self-regulated goal pursuit. Experiencing state interest stimulates spontaneous, focused attention, which reduces reliance on deliberate and effortful executive control (Hidi & Renninger, 2006). In educational environments, interest directly predicts the adoption of deep cognitive processing strategies over shallow surface memorisation (Schiefele, 1991). Furthermore, it serves as an emotional buffer against ego depletion, sustaining psychological resources during demanding tasks (Silvia, 2008; Thoman et al., 2011). <quiz display="simple"> {According to Silvia's (2008) appraisal model, high novelty-complexity automatically sparks interest, even if a person feels they have zero capacity or coping potential to understand it: |type="()"} + True - False </quiz> == Theoretical frameworks: Control-value and meaning-attentional models == To understand how individuals transition between profound boredom and energised interest, psychological science relies on multidimensional theoretical frameworks that link cognitive appraisals, environmental demands, and emotional outcomes (Pekrun, 2006; Westgate & Wilson, 2018). Rather than viewing emotional and motivational states as static personality traits, contemporary models conceptualise state boredom and state interest as dynamic, functional barometers driven by continuous evaluations of control, value, novelty, and meaning (Silvia, 2008). These theoretical models provide the structural lens through which cognitive and motivational processes can be systematically analysed and applied. === Pekrun's control-value theory of achievement emotions === Pekrun's (2006) control-value theory posits that achievement emotions are systematically governed by two primary cognitive appraisals: subjective control, which is the perception of personal agency over an activity, and subjective value, which represents the personal importance assigned to outcomes. State boredom typically peaks under conditions of mismatched control and low intrinsic value, manifesting either as deficient control when demands overwhelm capability or excessive control when tasks are trivial (Pekrun et al., 2010). Conversely, state interest emerges when an individual perceives moderate-to-high control paired with high intrinsic value, transforming the learning process into an inherently rewarding pursuit (Schiefele, 1991). For example, in the opening scenario, when Megan is forced to memorise exhaustive, repetitive lists of historical data without practical application, she experiences excessive control coupled with zero value, triggering acute boredom. Conversely, state interest emerges when an individual perceives moderate-to-high control paired with high intrinsic or attainment value, transforming the learning process into an inherently rewarding pursuit. === Silvia's two-component appraisal model of interest === Complementing Pekrun's framework, Silvia's (2005, 2008) appraisal model explains that state interest is an epistemic emotion triggered by two sequential cognitive evaluations: novelty-complexity and coping potential.   * Primary appraisal: Evaluates whether a stimulus is novel, complex, ambiguous, or unexpected. This evaluation automatically captures attention and initiates exploratory processing.   * Secondary appraisal: Assesses personal coping potential—the subjective evaluation of whether one possesses the cognitive resources, knowledge, and skills required to master the stimulus.   When high novelty is paired with high coping potential, individuals experience intense epistemic interest. However, if a stimulus is novel but exceeds coping potential (i.e., it is too complex or confusing), the individual experiences anxiety or confusion rather than engagement. This highlights why optimal challenge is a prerequisite for interest development. === Westgate and Wilson's meaning and attentional components model === While control-value theory focuses primarily on structured achievement contexts, Westgate and Wilson's (2018) Meaning and Attentional Components (MAC) model isolates the immediate psychological architecture of boredom. The MAC model proposes that boredom stems from two independent cognitive deficits:   # An attentional mismatch: Occurs when cognitive demands either overwhelm working memory capacity or fail to meet baseline neural stimulation thresholds.   # A meaning deficit: Arises when an activity lacks personal purpose, existential value, or relevance to broader life goals.   This theoretical distinction is crucial because it explains why individuals often experience profound disengagement even during routine, highly predictable tasks that they technically possess complete control and high coping potential over. An individual can easily pay attention to a boring task if they find inherent meaning in it; conversely, if an activity feels entirely purposeless, attention inevitably collapses regardless of how simple the task is to execute. {{example}} === Sansone and Thoman's self-regulation of motivation model === Expanding on how individuals navigate these affective states, Sansone and Thoman (2005) proposed that learners actively self-regulate motivation by restructuring mundane tasks to make them more engaging. Individuals implement interest-enhancing strategies, such as creating personal mini-challenges or adding playful elements to otherwise tedious activities (Sansone & Thoman, 2005). Long-term goal achievement therefore requires balancing disciplined effort with the dynamic generation of situational interest, bridging the gap between objective instructional demands and subjective motivational relevance (Hulleman & Harackiewicz, 2009). === Critical perspective on theoretical integration === While these models provide robust explanations, a critical analysis reveals notable tensions between them. Pekrun's control-value theory treats control and value as broad global appraisals, whereas Silvia's model focuses sharply on micro-appraisals of novelty and coping potential. Integrating these frameworks reveals that boredom and interest are not absolute opposites on a single continuum, but rather dual regulatory systems. Boredom acts as a signal of misfit (attentional mismatch or meaning deficit), whereas interest acts as an approach signal of growth and mastery. Future theoretical models must better account for the neurobiological interplay between default mode network (DMN) mind-wandering and dopaminergic reward pathways to fully capture how these cognitive appraisals translate into physiological arousal. <quiz display="simple"> {According to the MAC model (Westgate & Wilson, 2018), a person can experience boredom during a task even when the difficulty is optimal, provided they find the activity lacking in personal meaning or value: |type="()"} + True - False </quiz> == Research and empirical investigations == Psychological research has increasingly moved away from treating boredom and interest as minor emotional by-products, establishing them instead through rigorous empirical paradigms, including experience sampling methodology (Goetz et al., 2014), psychophysical attentional tasks (Eastwood et al., 2012), and longitudinal field interventions (Hulleman & Harackiewicz, 2009). Critical evaluation of this literature reveals how structural task features interact with individual cognitive vulnerabilities to dictate whether engagement is maintained or collapses into aversive disengagement. These empirical findings provide the evidentiary foundation for understanding the real-world behavioural consequences of affective states. === Experience sampling methodology and boredom subtypes === Goetz et al. (2014) transformed the assessment of academic emotions using experience sampling methodology (ESM) across cohorts, capturing real-time emotional fluctuations {{how}} {{who}} {{where}} rather than relying on retrospective evaluations. Their findings invalidated the assumption that boredom is a uniform, flat state of low arousal, identifying five distinct phenomenological subtypes (indifferent, apathetic, calibrating, searching, and reactant) that differ in valence, appraisals, and physiological activation (Goetz et al., 2014).    Subsequent ecological momentary assessments (EMA) confirmed {{who}} {{where}} that these subtypes dictate downstream behaviour differently; searching and reactant subtypes prompt immediate urges to escape, whereas indifferent and apathetic subtypes manifest as cognitive withdrawal. While ESM offers high ecological validity by reducing recall bias, repeated daily polling can introduce participant fatigue over extended periods (Goetz et al., 2014). === Attentional failures versus meaning deficits in experimental studies === While Eastwood et al. (2012) demonstrated that state boredom is fundamentally a bottom-up failure of sustained attention, Westgate and Wilson (2018) proved {{how}} {{who}} {{where}} that under-stimulation alone fails to induce boredom if a task possesses perceived subjective meaning. Synthesising these views, perceptual-attentional constraints and existential meaning deficits represent dual, independent pathways to disengagement. === Psychosocial consequences of trait boredom proneness and meta-analytic evidence === Population-based research utilising the Boredom Proneness Scale (Farmer & Sundberg, 1986) has consistently linked chronic trait susceptibility {{explain}} to severe psychosocial maladjustment and psychopathology. Recent systematic reviews and large-scale meta-analytic evidence confirm robust positive correlations between elevated boredom proneness and behavioural addictions, academic procrastination, emotional dysregulation, and depressive symptomatology (Danckert et al., 2018; Tam et al., 2021) {{expand}}. Expanding on these associations, recent comprehensive meta-analyses examining boredom and digital media use demonstrate a large positive pooled effect size (''r'' = .342) between trait boredom and problematic digital media use, compared to a much smaller association with non-problematic use (''r'' = .084) (Camerini et al., 2023). Longitudinal tracking demonstrates that individuals high in trait boredom exhibit heightened vulnerability to compulsive digital media consumption, utilising rapid-fire online scrolling and smartphone notifications as a maladaptive regulatory attempt to escape chronic under-arousal and down-regulate negative affect (Camerini et al., 2023). However, a critical limitation across much of this correlational literature is its heavy reliance on cross-sectional self-report designs, which restricts definitive causal inference due to shared-method variance and potential reporting biases, necessitating more prospective cross-lagged panel designs (Farmer & Sundberg, 1986; Danckert et al., 2018). === Psychophysiological and neurobiological underpinnings === Neurobiologically, functional magnetic resonance imaging (fMRI) studies reveal that state boredom is associated with altered functional connectivity within the brain's default mode network (DMN), particularly involving the precuneus and [https://qbi.uq.edu.au/brain/brain-anatomy/lobes-brain medial prefrontal cortex] (Danckert & Merrifield, 2018). When individuals encounter monotonous or under-stimulating tasks, failure of frontoparietal control networks to suppress task-irrelevant DMN mind-wandering generates subjective restlessness and attentional lapses. In contrast, states of high interest recruit dopaminergic reward pathways (ventral striatum) and executive control networks, facilitating sustained, effortless cognitive focus without psychological depletion (Hidi & Renninger, 2006).    === Experimental validation of interest and utility-value interventions === Hulleman and Harackiewicz (2009) demonstrated the causal efficacy of cultivating situational interest through a randomised controlled field experiment. Assigning {{ic|how many?}} high school science students {{where}} to write brief reflections connecting course material to their personal lives yielded significant gains in situational interest and course performance, particularly among students with low initial expectations (Hulleman & Harackiewicz, 2009). These empirical findings validate Sansone and Thoman's (2005) self-regulation theory, proving that learners are not passive victims of uninteresting curricula; rather, targeted cognitive framing can successfully bridge the gap between objective instructional demands and subjective motivational relevance (Hulleman & Harackiewicz, 2009). Subsequent educational trials have replicated these findings across diverse learning contexts, proving that systematic manipulation of utility value successfully converts aversive state disengagement into sustained, approach-oriented engagement {{f}}. == Integration: Bridging theory and empirical research == Synthesising theoretical frameworks with empirical investigations reveals how cognitive appraisals, attentional mechanisms, and subjective valuations dictate real-world motivational outcomes, explaining why individuals transition between disengagement and immersion. === Empirical validation and refinement of appraisal models === Silvia's (2005, 2008) appraisal model posits that interest is triggered by novelty-complexity and coping potential. Goetz et al.'s (2014) experience sampling methodology (ESM) empirically substantiates this by showing that classroom emotional states fluctuate dynamically in response to these micro-appraisals. When instruction matches student coping potential and introduces moderate novelty, high-arousal engagement and searching boredom are activated rather than apathetic withdrawal, validating static appraisal theories in naturalistic settings. === Resolving theoretical tensions through experimental paradigms === Empirical research reconciles apparent tensions between competing models of boredom. The debate {{f}} between Eastwood et al. (2012), who view boredom as a bottom-up attentional failure, and Westgate and Wilson (2018), who emphasize top-down meaning deficits via the MAC model, highlights the need for an integrated perspective. Eastwood et al. show that working memory and sustained attention impairments generate bottom-up disengagement during monotonous tasks. Conversely, Westgate and Wilson demonstrate that top-down cognitive appraisals of personal utility can override under-stimulation. Integrating these findings with Pekrun's (2006) control-value framework reveals that comprehensive emotional models must account for both perceptual-attentional constraints and existential meaning: an individual may possess full cognitive control over a task yet experience acute boredom if top-down value appraisals are missing. === Translating theory into self-regulation and applied interventions === Sansone and Thoman's (2005) model posits that learners actively regulate their own motivation, a premise empirically validated by Hulleman and Harackiewicz's (2009) randomised controlled trials. Their experiments demonstrated that brief utility-value reflections enhance situational interest and academic performance by aligning curriculum demands with personal relevance. Ultimately, targeted cognitive reframing reshapes motivational appraisals, effectively transforming boredom into sustained engagement. == Individual differences: Trait boredom, curiosity, and personality == Trait boredom is a stable personality susceptibility involving chronic difficulty in engaging attention and finding daily meaning (Farmer & Sundberg, 1986). Individuals high in trait boredom exhibit heightened vulnerability to behavioural addictions, academic procrastination, and distress, frequently seeking external stimulation to compensate for internal under-arousal (Danckert et al., 2018; Tam et al., 2021). In contrast, trait curiosity acts as an intrinsic resource buffering against disengagement (Litman, 2005). Highly curious individuals actively seek novel stimuli, framing challenging tasks as opportunities for exploration rather than frustration (Litman, 2005; Silvia, 2008). These profiles demonstrate that vulnerability to boredom versus capacity for interest is determined by enduring trait structures interacting with task affordances. Neurobiologically, individual susceptibility to chronic boredom is linked to functional connectivity differences within the brain's default mode network (DMN) (Danckert & Merrifield, 2018). When individuals with high boredom proneness encounter monotonous tasks, their DMN fails to suppress task-irrelevant mind-wandering efficiently, leading to subjective restlessness and attentional lapses (Danckert & Merrifield, 2018). Understanding these individual differences allows educators and practitioners to tailor learning environments to support vulnerable learners. === Psychological dimension matrix === Although state boredom and state interest operate as dual self-regulatory signals, they diverge sharply across core affective, cognitive, and motivational dimensions (see Table 1). '''Table 1''' ''Comparison of Psychological Dimensions Between State Boredom and State Interest'' {| class="wikitable" style="margin: auto;" |- ! Dimension !State Boredom!! State Interest !! Key Citations |- | '''Affective Valence''' |Unpleasant, aversive|| Pleasant, invigorating || Eastwood et al. (2012); Silvia (2008) |- | '''Arousal Level''' |Variable (apathetic low to reactant high)|| Moderate to high (engaged alertness) || Goetz et al. (2014); Silvia (2005) |- |'''Attentional State''' |Effortful, frequent mind-wandering |Effortless absorption, sustained focus |Westgate & Wilson (2018) |- |'''Primary Appraisals''' |Low intrinsic value; control mismatch |High novelty-complexity; high coping |Pekrun (2006); Silvia (2008) |- |'''Motivational Goal''' |Avoidance, task-switching, escape |Approach, exploration, knowledge acquisition |Bench & Lench (2013); Hidi & Renninger (2006) |- |'''Time Perception''' |Overestimated ("time drags") |Underestimated ("time flies") |Eastwood et al. (2012) |} == Applied interventions: Transforming boredom into interest == Psychological science provides actionable frameworks to convert maladaptive state boredom into productive situational interest. One highly validated approach is the utility-value intervention, where learners explicitly connect course material to personal goals; experimental trials confirm this significantly boosts interest and performance, particularly among students with low initial expectations (Hulleman & Harackiewicz, 2009). Furthermore, task-crafting allows individuals to introduce playful elements and autonomy into tedious routines, bridging the gap between objective demands and subjective relevance (Sansone & Thoman, 2005). Finally, dynamically calibrating task difficulty prevents both overload anxiety and under-stimulation, fostering sustained engagement (Pekrun, 2006; Silvia, 2008). ==Conclusion== How do boredom and interest shape emotional and motivational lives? Psychological science reveals that state boredom and state interest act as powerful, complementary internal barometers guiding daily attention and behaviour. Rather than being mere psychological nuisances, boredom functions as an adaptive evolutionary signal warning individuals when an activity lacks personal meaning or optimal challenge, whereas interest serves as an approach-oriented engine driving exploration and mastery. As demonstrated by Pekrun's control-value theory, Silvia's appraisal framework, and Westgate and Wilson's MAC model, these states are governed by continuous evaluations of control, value, novelty, and existential purpose. When appraisals align, learners enter states of effortless immersion; when they break down, disengagement follows. Crucially, individuals are not passive victims of unengaging environments. By applying targeted psychological strategies, such as utility-value reflections, task-crafting, and calibrating challenge, students and professionals can successfully transform aversive boredom into enduring interest, bridging the gap between objective demands and personal fulfilment. ==See also== * [[wikipedia:Attention|Attention]] (Wikipedia) * [[wikipedia:Boredom|Boredom]] (Wikipedia) * [[wikipedia:Curiosity|Curiosity]] (Wikipedia) * [[Motivation and emotion/Book/2021/Curiosity and interest|Curiosity and interest]] (Wikiversity book chapter, 2021) * [[wikipedia:Flow (psychology)|Flow (psychology)]] (Wikipedia) * [[Motivation and emotion/Book/2020/Flow and optimal experience|Flow and optimal experience]] (Wikiversity book chapter, 2020) * [[wikipedia:Interest (emotion)|Interest (emotion)]] (Wikipedia) * [[wikipedia:Intrinsic motivation|Intrinsic motivation]] (Wikipedia) * [[Motivation and emotion/Book/2019/Intrinsic motivation in education|Intrinsic motivation in education]] (Wikiversity book chapter, 2019) * [[Motivation and emotion/Book/2025/Metacognition and emotional regulation|Metacognition and emotional regulation]] (Wikiversity book chapter, 2025) * [[Motivation and emotion/Book/2022/Self-regulation and academic procrastination|Self-regulation and academic procrastination]] (Wikiversity book chapter, 2022) ==References== {{Hanging indent|1= Bench, S. W., & Lench, H. C. (2013). On the function of boredom. ''Behavioral Sciences'', ''3''(3), 459–472. https://doi.org/10.3390/bs3030459 Camerini, A.-L., Morlino, S., & Marciano, L. (2023). Boredom and digital media use: A systematic review and meta-analysis. ''Computers in Human Behavior Reports'', ''11'', Article 100313. https://doi.org/10.1016/j.chbr.2023.100313 Clay, G., Mlynski, C., Korb, F. M., Goschke, T., & Job, V. (2024). Autonomic nervous system activity during state boredom. ''Psychophysiology'', ''61''(4), Article e14507. https://doi.org/10.1111/psyp.14507 Danckert, J., & Merrifield, C. (2018). Boredom, sustained attention and the default mode network. ''Experimental Brain Research'', ''236''(9), 2507–2518. https://doi.org/10.1007/s00221-016-4617-5 Danckert, J., Mugon, J., Struk, A., & Eastwood, J. (2018). Boredom: What is it, why does it matter, and what can we do about it? ''Cognition and Emotion'', ''32''(6), 1163–1172. https://doi.org/10.1080/02699931.2018.1462148 Eastwood, J. D., Frischen, A., Fenske, M. J., & Smilek, D. (2012). The unengaged mind: Defining boredom in terms of attention. ''Perspectives on Psychological Science'', ''7''(5), 482–495. https://doi.org/10.1177/1745691612456044 Farmer, R., & Sundberg, N. D. (1986). Boredom proneness: The development and correlates of a new scale. ''Journal of Personality Assessment'', ''50''(1), 4–17. https://doi.org/10.1207/s15327752jpa5001_2 Goetz, T., Frenzel, A. C., Hall, N. C., Nett, U. E., Pekrun, R., & Lipnevich, A. A. (2014). Types of boredom: An experience sampling approach. ''Motivation and Emotion'', ''38''(3), 401–419. https://doi.org/10.1007/s11031-013-9385-y Hidi, S., & Renninger, K. A. (2006). The four-phase model of interest development. ''Educational Psychologist'', ''41''(2), 111–127. https://doi.org/10.1207/s15326985ep4102_4 Hulleman, C. S., & Harackiewicz, J. M. (2009). Promoting interest and performance in high school science classes. ''Science'', ''326''(5958), 1410–1412. https://doi.org/10.1126/science.1177067 Litman, J. (2005). Curiosity and the pleasures of learning: Wanting and liking new information. ''Cognition and Emotion'', ''19''(6), 793–814. https://doi.org/10.1080/02699930541000101 Pekrun, R. (2006). The control-value theory of achievement emotions: Assumptions, corollaries, and implications for educational research and practice. ''Educational Psychology Review'', ''18''(4), 315–341. https://doi.org/10.1007/s10648-006-9029-9 Pekrun, R., Goetz, T., Daniels, L. M., Stupnisky, R. H., & Perry, R. P. (2010). Boredom in achievement settings: Exploring control–value antecedents and performance outcomes of a neglected emotion. ''Journal of Educational Psychology'', ''102''(3), 531–549. https://doi.org/10.1037/a0019243 Renninger, K. A., & Hidi, S. (2015). ''The power of interest for motivation and engagement''. Routledge. https://doi.org/10.4324/9781315771045 Sansone, C., & Thoman, D. B. (2005). Interest as the missing motivator in self-regulation. ''European Psychologist'', ''10''(3), 175–186. https://doi.org/10.1027/1016-9040.10.3.175 Schiefele, U. (1991). Interest, learning, and motivation. ''Educational Psychologist'', ''26''(3–4), 299–323. https://doi.org/10.1080/00461520.1991.9653136 Silvia, P. J. (2005). What is interesting? Exploring the appraisal structure of interest. ''Emotion'', ''5''(1), 89–102. https://doi.org/10.1037/1528-3542.5.1.89 Silvia, P. J. (2008). Interest—The curious emotion. ''Current Directions in Psychological Science'', ''17''(1), 57–60. https://doi.org/10.1111/j.1467-8721.2008.00548.x Tam, K. Y. Y., Van Tilburg, W. A. P., & Chan, C. S. (2021). What is boredom proneness? A theoretical investigation. ''Personality and Social Psychology Review'', ''25''(3), 291–310. https://doi.org/10.1177/10888683211010297 Thoman, D. B., Smith, J. L., & Silvia, P. J. (2011). The resource replenishment function of interest. ''Social Psychological and Personality Science'', ''2''(6), 592–599. https://doi.org/10.1177/1948550611402521 Westgate, E. C., & Wilson, T. D. (2018). Boring by design: A Meaning and Attentional Components (MAC) model of boredom. ''Psychological Review'', ''125''(5), 689–713. https://doi.org/10.1037/rev0000097 }} ==External links== * [https://www.hiddenbrain.org/podcast/boredom/ Boredom] (Hidden Brain Media) * [https://www.ted.com/talks/manoush_zomorodi_how_boredom_can_lead_to_your_most_brilliant_ideas How boredom can lead to your most brilliant ideas] (TED) * [https://www.artofmanliness.com/character/self-improvement/podcast-686-the-psychology-of-boredom/ The psychology of boredom] (The Art of Manliness) [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Boredom]] [[Category:Motivation and emotion/Book/Interest]] f5v729elxhjqldmn18fuwmo85cy5226 1 331575 2844965 2843838 2026-11-09T11:38:11Z Jtneill 10242 Minor additions to the Book Chapter feedback 2844965 wikitext text/x-wiki ==References== Great start on the scenario. Here are some starting articles to help you get started 10.1007/s40653-026-10.3390/children13010122 - 10.3389/fpsyg.2026.1684921 - Psychotherapy for complex post-traumatic stress disorder: efficacy and therapeutic factors 10.1080/26408066.2026.2633764 - The Experience of Posttraumatic Growth Among Sexual Violence Survivors: A Meta-Ethnographic Review and Synthesis of Qualitative Literature [[User:U3263365|U3263365]] ([[User talk:U3263365|discuss]] •[[Special:Contributions/U3263365|contribs]]) 05:12, 27 August 2026 (UTC) --[[User:U3263365|U3263365]] ([[User talk:U3263365|discuss]] • [[Special:Contributions/U3263365|contribs]]) 05:39, 27 August 2026 (UTC) <!-- Official topic development feedback --> {{METF/2026 |1= <!-- Title --> # Title and subtitle are correctly worded and use [[w:Letter case#Sentence casing|sentence casing]] |2= <!-- Headings --> # See earlier comment about [[#heading casing|heading casing]] <!-- Heading structure --> <!-- Conceptual --> # Messy heading structure – needs work (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) # The top-level headings are the focus questions. Consider paraphrasing these headings. # Avoid having sections with only 1 sub-heading – use 0 or 2+ sub-headings # Consider dropping the 3rd heading level / Remove citations as headings # Check grammar (e.g,. possessive apostrophe missing) |3= <!-- Overview--> # Very good to excellent <!-- GenAI ---> # Does this section include [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, it needs to be acknowledged as such in the edit summaries, otherwise it violates academic integrity. <!-- Scenario --> # A scenario or case study is presented in a feature box at the start of this section # I moved an image into the feature box to help attract reader interest <!-- Description --> # A promising description of the problem/topic is planned or presented <!-- Style --> # Use 3rd person point of view for main body text (except 1st/2nd person point of view can work within feature boxes for scenarios) <!-- Focus questions --> # Focus questions are aligned with sub-title and top-level headings |4= <!-- Key points--> <!-- Overall --> # Partial development # Overly focused on individual studies; instead focus on the key theoretical perspectives and how well these are supported by research evidence <!-- Theory and research --> ## Strive for an integrated balance of the best psychological theory and research about this topic, with practical examples. <!-- Citations --> # Insufficient use of citations <!-- Other --> # For sections with sub-sections, provide key points for an overview paragraph prior to branching into the sub-headings <!-- Conclusion --> # Conclusion hasn't been developed # What are the practical, take-home messages? (address the focus questions) |5= <!-- Figure --> # Relevant figure(s) are presented and captioned <!-- Caption --> # Figure caption(s) provide(s) a somewhat clear description that is connected with the main text, but could be improved (adjusted) <!-- Cite --> # Cite each figure at least once in the main text using APA style (e.g., see Figure 1) # Well done on creating and uploading your own image! {{smile}}—this can also be listed on your user page as a social contribution |6= <!-- Learning feature --> <!-- Interwiki links ---> # Add in-text [[m:Help:Interwiki linking|interwiki links]] for first mention of key terms to [[w:|Wikipedia]] and/or [[Motivation and emotion/Book|book chapters]] (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- Scenarios/examples/case studies --> # Consider incorporating additional scenarios, examples, or case studies to illustrate key concepts. These could build on the Overview scenario or introduce new real-world situations in the main body of the chapter to demonstrate how the concepts apply in practice. <!-- Quiz --> # Consider including quiz question(s) about the take-home messages <!-- Tables --> # Also consider using tables to summarise key information |7= <!-- References --> <!-- Overall --> # To be developed <!-- Systematic reviews --> # What are the most relevant systematic reviews/meta-analyses about this topic? |8= <!-- Resources --> <!-- See also --> # See also ## To be developed (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- External links --> # External links ## To be developed (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) ## Link to the most relevant external resources about this topic |9= <!-- User page --> # Basic <!-- Description about self --> # Very brief description about self – consider expanding # Add description about self <!-- Links to profile(s) --> # Consider linking to your [https://portfolio.canberra.edu.au/ eportfolio] page and/or any other professional online profile or resume such as [https://www.linkedin.com/ LinkedIn]. This is not required, but it can be useful to interlink your professional networks. <!-- Link to book chapter --> # Add link to book chapter |10= <!-- Social contribution --> # None summarised on user page with direct link(s) to evidence (see [[Motivation and emotion/Tutorials/Wiki editing#Social contributions|Tutorial 2]]). Looking ahead to the book chapter, see [[Motivation and emotion/Assessment/Chapter#Socialcontribution|social contributions]]. }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 05:53, 8 September 2026 (UTC) == Heading casing == {| style="float: center; background:transparent;color:inherit;" |- | [[File:Crystal Clear app ktip.svg|48px|left]] | {{#if:|Hi [[User:{{{1}}}|{{{1}}}]].|}} FYI, the recommended [[Wikiversity]] heading style uses [[w:Letter case#Sentence_case|sentence casing]]. For example:<br> <big><big>Self-determination theory</big></big> rather than <big><big>Self-Determination Theory</big></big> Here's an example chapter with correct heading casing: [[Motivation and emotion/Book/2019/Growth mindset development|Growth mindset development]] -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:19, 2 November 2026 (UTC) |} <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an insufficient chapter mainly because there is only a brief section about the topic (how to rebuild trust); most of the chapter is about the problems associated with trauma in relationships which is not the target topic. <!-- Overall - Edit summaries --> #* The chapter has a brief editing history <!-- Overall - GenAI --> #* This chapter appears to be human-written <!-- Overall – Citations --> # Reasonably good use of academic, peer-reviewed citations to support claims <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion/Book/2026/Trust_rebuilding_after_trauma&action=history these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box <!-- Overview – Explains problem --> # Briefly explains the psychological problem or phenomenon; provide more detail # Convert the explanation of the problem from bullet-points into sentences and paragraphs <!-- Overview – Focus questions --> # The focus questions are basic # Expand the third focus question # The focus questions could be improved by: |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Insufficient; a promising range of ideas are presented but the content is insufficiently focused on rebuilding trust # Reduce general theoretical background (e.g., about the problems with relationship trauma). Instead, summarise and link to related resources (i.e., other book chapters and/or Wikipedia articles). Increase emphasis on [[wikt:substantive|substantive]] aspects of theory that relate directly to the specific topic (i.e., the sub-title question). <!-- Theory – Builds on --> # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insufficient depth is provided about key theory(ies) related to the target topic; the material about rebuilding is promising, but brief <!-- Theory – Tables/Figures/Lists --> # Insufficient use of tables, figures, and/or lists to clearly convey key relevant theoretical information <!-- Theory – Citations --> # In some places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. <!-- Theory – Examples --> # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Insufficient review of relevant research about the topic (how to rebuild trust) # Insufficient use of relevant systematic reviews and/or meta-analyses # More detail about key studies would be ideal # Secondary citations are overused; consult the best original sources about the topic <!-- Research – Critical thinking --> # Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Insufficient integration between the most relevant theory(ies) and the best research # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Basic summary and conclusion # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are summarised in a basic way <!-- Conclusion – Take-home messages --> # Add practical, take-home message(s) |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is basic <!-- Style – Paragraphs --> ## Some paragraphs are overly long. Communicate one key idea per paragraph in three to five sentences. <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. <!-- Style – Layout --> # Layout ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings ## See earlier comment about [[#Heading casing|heading casing]] ## Provide more descriptive headings ## Remove abbreviations/citations from headings (fixed) ## Learning features should not have headings; they should be embedded like figures and tables <!-- Style – Grammar --> # Grammar ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Use past tense when describing research studies, although implications of findings could be in the present tense <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] <!-- Style – Figures --> ## Figures ### Reasonably well captioned ### Figure 2 has been nominated for deletion due to likely copyright violation <!-- Style – Figures - Citations --> ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Citations --> # Citations use reasonably good [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) ## Do not include author first name or initials ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses <!-- Style – References --> ## References use basic APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Include dois where available |8= <!-- Learning features comments... --> # Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Insufficient use of figure(s) # No use of table(s) # No use of feature boxes other than the opening scenario # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages related to the target topic # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end # Use the [[Help:Quiz]] quiz tool to make the quizzes interactive <!-- Learning features – See also --> # Insufficient use of the [[{{PAGENAME}}#See also|See also]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#See also|template]] ## Add more links <!-- Learning features – External links --> # Insufficient use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] ## Add more links |9= <!-- Social contribution comments... --> # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:19, 2 November 2026 (UTC) 0x2k8biizokx9l9jt341f7n10l4dw0e 1 331596 2844961 2842228 2026-11-09T10:53:55Z Jtneill 10242 Book chapter feedback 2844961 wikitext text/x-wiki == Depth == How wonderfully in-depth, the one criticism I would have though, as unlikely as it is that you will see this in time, is that some of the links in your see also section appear to be broken, just as a heads up in case you catch this in time. == Great Work == Funny how an article on boredom and interest kept '''my''' interest. Good read, keep up the great work. [[Special:Contributions/&#126;2026-46818-57|&#126;2026-46818-57]] ([[User talk:&#126;2026-46818-57|talk]]) 11:14, 27 August 2026 (UTC) == Heading casing == {| style="float: center; background:transparent;color:inherit;" |- | [[File:Crystal Clear app ktip.svg|48px|left]] | {{#if:U3239431|Hi [[User:U3239431|U3239431]].|}} FYI, the recommended [[Wikiversity]] heading style uses [[w:Letter case#Sentence_case|sentence casing]]. For example:<br> <big><big>Self-determination theory</big></big> rather than <big><big>Self-Determination Theory</big></big> Here's an example chapter with correct heading casing: [[Motivation and emotion/Book/2019/Growth mindset development|Growth mindset development]] -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:19, 5 September 2026 (UTC) |} <!-- Official topic development feedback --> {{METF/2026 |1= <!-- Title --> # Title and/or subtitle not correctly worded and/or didn't use [[w:Letter case#Sentence casing|sentence casing]] (fixed) |2= <!-- Headings --> # See earlier comment about [[#heading casing|heading casing]] <!-- Heading structure --> <!-- 2-level --> # Clear [[Motivation and emotion/Assessment/Major project/Structure|2-level heading structure]] # Promising [[Motivation and emotion/Assessment/Major project/Structure|2-level heading structure]] – could benefit from further development and/or refinement <!-- Other ---> # Avoid having sections with only 1 sub-heading – use 0 or 2+ sub-headings <!-- Alignment with focus questions --> # Excellent alignment between sub-title, focus questions, and heading structure # Are the headings based on [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, this needs to be acknowledged in the edit summaries, otherwise it violates academic integrity. |3= <!-- Overview--> # Excellent – Scenario, image, evocative description of the problem/topic, and focus questions <!-- GenAI ---> # Does this section include [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, it needs to be acknowledged as such in the edit summaries, otherwise it violates academic integrity. <!-- Scenario --> # A scenario or case study is presented in a feature box at the start of this section # An image was moved into the feature box to help attract reader interest <!-- Description --> # A clear description of the problem/topic is planned or presented # Use present, rather than future, tense (fixed) <!-- Focus questions --> # Focus questions are aligned with sub-title and top-level headings |4= <!-- Key points--> <!-- Overall --> # Excellent – key points are well developed for each section <!-- Scope --> # The scope is about right, but it may be that all planned aspects cannot be reasonably covered within the book chapter word count; in that case, be selective and concentrate on key aspects that address the question in the sub-title <!-- Theory and research --> # Promising balance of theory and research # Do these key points include [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, this needs to be acknowledged in the edit summaries, otherwise it violates academic integrity. <!-- Conclusion --> # Conclusion is well underway # What are the practical, take-home messages? (address the focus questions) |5= <!-- Figure --> # Excellent - Relevant figure(s) presented, captioned, and cited <!-- Caption --> # Figure caption(s) should include '''Figure X'''. ... (fixed) <!-- Cite --> # Figure(s) are cited at least once in the main text <!-- Learning feature --> <!-- Interwiki links ---> # Excellent in-text [[m:Help:Interwiki linking|interwiki links]] for first mention of key terms to [[w:|Wikipedia]] and/or [[Motivation and emotion/Book|book chapters]] <!-- Scenarios/examples/case studies --> # Consider use of more scenarios/examples/case studies <!-- Quiz --> # Promising use of quiz question(s) <!-- Tables --> # Excellent use of table(s) |7= <!-- References --> <!-- Overall --> # Very good <!-- Systematic reviews --> # What are the most relevant systematic reviews/meta-analyses about this topic? <!-- APA style --> # Check and correct [https://apastyle.apa.org/instructional-aids/reference-guide.pdf APA referencing style]: ## [[Help:Wikitext quick reference|italicisation]] <!-- Resources --> <!-- See also --> # See also ## Excellent <!-- External links --> # External links ## Excellent |9= <!-- User page --> # Used effectively <!-- Description about self --> # Excellent description about self provided <!-- Links to profile(s) --> # Consider linking to your [https://portfolio.canberra.edu.au/ eportfolio] page and/or any other professional online profile or resume such as [https://www.linkedin.com/ LinkedIn]. This is not required, but it can be useful to interlink your professional networks. <!-- Link to book chapter --> # A link to the book chapter is provided |10= <!-- Social contribution --> # Good – two out of three types of contributions made with direct link(s) to evidence. The other type of contribution is making: #* direct improvements to other [[Motivation and emotion/Book|chapters (past or current)]] # To add direct links to evidence of Wikiversity edits or comments: view the page history, select the version of the page before and after your contributions, click "compare selected revisions", and paste the comparison URL on your user page. For more info, see [[Motivation and emotion/Assessment/Chapter#Making and summarising social contributions|Making and summarising social contributions]]. This was demonstrated in [[Motivation and emotion/Tutorials/Wiki editing#Social contributions|Tutorial 2]]. }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 09:19, 5 September 2026 (UTC) == Resource recommendation == Great chapter, your discussion of boredom as an attentional and meaning-related state fits well with current research. Elpidorou (2014) also points out that boredom can serve as a useful self-regulatory function, nudging people toward more meaningful or appropriately challenging activities. I have provided a reference below for you that may be useful. Elpidorou, A. (2014). The bright side of boredom. ''Frontiers in Psychology'', ''5'', 1245. <nowiki>https://doi.org/10.3389/fpsyg.2014.01245</nowiki> [[User:StudentUC2026|StudentUC2026]] ([[User talk:StudentUC2026|discuss]] • [[Special:Contributions/StudentUC2026|contribs]]) 03:19, 23 October 2026 (UTC) <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is an insufficient chapter # The main area(s) for potential improvement: #* integrate discussion of theory and research throughout, rather than treating them separately #* improve the quality of written expression so that it is more accessible to a general audience #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution #* write more in your own words—unacknowledged [[Motivation and emotion/Assessment/Using generative AI]] is over-used despite multiple warnings #* invest more time (I suspect that less than the [[Motivation and emotion/Assessment#Assessment items|recommended 75 hours]] were invested) <!-- Overall - Edit summaries --> # This chapter has a brief editing history # Use more specific [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to clearly communicate the changes made in each edit <!-- Overall - GenAI --> # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Reasonably good use of academic, peer-reviewed citations to support claims # Only cite sources that you consult <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FBoredom_and_interest&diff=2844960&oldid=2840618 these copy edits] |2= <!-- Overview – Comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Reasonably good scenario or case study; could be made more compelling and accessible by simplifying the languate # Use an example that a wider audience can relate to; less than 5% of the world population are university students <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box <!-- Overview – Explains problem --> # Explains the psychological problem or phenomenon reasonably well <!-- Overview – Focus questions --> # The focus questions are promising but problematic # The focus questions could be improved by: ## being simplified and more closely tied to the topic (i.e., the sub-title) ## matching the top-level headings more closely ## being human-written rather than AI-written without acknowledgement |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement # The description of theory could be improved by simplifying the language and using a human-written rather than unacknowledge genAI language # There's a weird bias throughout towards educational contexts, even though this is not part of the question. This has possibly arisen due to noisy loading of the educational scenario context in genAI prompting. <!-- Theory – Builds on --> # Builds in a basic way on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Promising depth is provided about key theory(ies), but it doesn't appear to be based on human reading and thinking and overrelies on unacknowledged use of genAI <!-- Theory – Tables/Figures/Lists --> # Insufficient/No use of tables, figures, and/or lists to convey key theoretical information <!-- Theory – Citations --> # In some places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. <!-- Theory – Examples --> # Insufficient use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Promising review of relevant research, but critically flawed by insufficient human reading and thinking and unacknowledged use of genAI # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # More detail about key studies would be ideal # In some, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. <!-- Research – Critical thinking --> # Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research # The research has been naively steered to focus on educational contexts, even though this isn't specified by the topic title or sub-title |5= <!-- Integration comments... --> # Basic, formulaic # Provide integrated rather than separate discussions of theory and research # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Insufficient as a human-derived cohesive summary of the best psychological theory and research about the topic # Reads like generic [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; write more compellingly in your own words # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are summarised in a basic way <!-- Conclusion – Focus questions --> # Address the focus questions <!-- Conclusion – Take-home messages --> # Add practical, take-home message(s) |7= <!-- Style comments... --> <!-- Style – Written expression --> ## The quality of written expression is basic (at best); the chapter appears to be heavily based on overuse of unacknowledged genAI content; a more convincing chapter would either use more human-written words and/or use finer-grained acknowledgement of genAI with publicly available links to the chatbot conversations as per the [[Motivation and emotion/Assessment/Using generative AI|unit's using genAI guidelines]] <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) <!-- Style – Abbreviations --> ## Abbreviations ### Only introduce abbreviations which are subsequently used ### Once an abbreviation has been established (e.g., ESM), use it consistently afterwards <!-- Style – Layout --> # Layout ## The headings could be more clearly aligned with the focus questions ## The chapter is overly aligned with the marking criteria (typical of low-quality genAI material) ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## Integrate research rather than having it as a stand-alone section(s) <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] ## [https://apastyle.apa.org/style-grammar-guidelines/numbers Express numbers under 10 using words (e.g., two) and 10 and over using numerals (e.g., 99)] ## Direct quotes are overused—it is better to communicate about concepts in your own words <!-- Style – Figures --> ## Figures ### Overly verbose caption <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text. Refer to each Figure using APA style (e.g., "(see Figure 1)"; do not use bold, italics, check and correct capitalisation) (fixed). <!-- Style – Tables --> ## Table(s) ### Reasonably well captioned <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Style – References --> ## References use excellent APA style ## Only cite and references sources that you have consulted <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent/Very good/Good/Reasonably good/Basic/Insufficient use of learning features <!-- Learning features – Wikipedia embedded links --> # Add more embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Move embedded links to non-peer-reviewed sources to the [[{{PAGENAME}}#External links|External links]] section # Add more embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # No use of figure(s) # Basic use of table(s) # No use of feature boxes other than the opening scenario # No use of scenarios, case studies, or examples, other than opening scenario <!-- Learning features – Quizzes --> # Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be improved by being more focused on the key points and/or take-home messages <!-- Learning features – See also --> # Insufficient use of the [[{{PAGENAME}}#See also|See also]] section ## Many links are broken <!-- Learning features – External links --> # Very good use of the [[{{PAGENAME}}#External links|External links]] section ## Add more links |9= <!-- Social contribution comments... --> # ~2 logged, useful, mostly moderate contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] # ~1 logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) hyperlinks to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 10:53, 9 November 2026 (UTC) 96yfs2m2isar3qpqlt5k6ir3sd8jen5 1 331611 2844957 2841460 2026-11-09T10:27:01Z Jack4234 3106762 2844957 wikitext text/x-wiki ==Generative AI statement== Generative AI (ChatGBT) was used as a supplementary tool during the development of this book chapter. Its main uses were to help generate ideas for structuring the chapter, improve the readability and flow of my writing, and assist with formatting elements such as interactive features, images, and text boxes. Generative AI was not used as a substitute for scholarly research, critical thinking, or independent analysis. All substantive information and claims in the chapter were drawn from scholarly literature and interpreted through my own analysis. I did not directly reproduce AI-generated content as academic evidence, and the final wording and argumentation were developed in my own words. Because generative AI can produce inaccurate or misleading information, any suggestions it provided were critically evaluated and cross-checked against reliable sources before use. I take full responsibility for the accuracy, interpretation, and the final presentation of the work submitted. Link to AI conversation: https://chatgpt.com/g/g-p-6a7dc8d61f0c8191ae45bf5b2fd4dee9-motivation-and-emotion/c/6a7dcc90-14d4-83ec-9083-c3a2bdf3b7ce - Jack4234 == Identity-based motivation as a companion to possible selves == Hi Jack4234, our chapters overlap - I'm writing [[Motivation and emotion/Book/2026/Indigenous Australian role models and motivation|Indigenous Australian role models and motivation]], and possible selves is one of the mechanisms I use to explain how role models influence goal pursuit. Two sources you might find useful, if you have not already got them: * Oyserman and Destin (2010) is a strong companion to Markus and Nurius (1986). Their contribution is explaining ''why'' possible selves sometimes fail to drive action: when a goal feels identity-incongruent, experienced difficulty gets interpreted as "this is pointless and not for people like me" rather than as a signal that the goal matters. That gives you a mechanism for the gap between holding a possible self and actually pursuing it. *: Oyserman, D., & Destin, M. (2010). Identity-based motivation: Implications for intervention. ''The Counseling Psychologist, 38''(7), 1001–1043. https://doi.org/10.1177/0011000010374775 * Morgenroth et al. (2015) may also be worth a look for their "representation of the possible" function - it connects possible selves back to where they come from. *: Morgenroth, T., Ryan, M. K., & Peters, K. (2015). The motivational theory of role modeling: How role models influence role aspirants' goals. ''Review of General Psychology, 19''(4), 465–483. https://doi.org/10.1037/gpr0000059 Happy to add a "See also" link from my chapter to yours if you would like to do the same - the two topics connect closely. [[User:Jshottt|Jshottt]] ([[User talk:Jshottt|discuss]] • [[Special:Contributions/Jshottt|contribs]]) 14:18, 27 August 2026 (UTC) :Hi there :I am writing the book chapter [[Motivation and emotion/Book/2026/Self-concept and motivation|Self-concept and motivation]], a topic which closely aligns to your focus on possible selves. Building on Jshottt's message here, I have been reading another interesting study by Oyserman about how identities drive goal pursuit. I think this could fit nicely in your 'When possible selves facilitate goal pursuit' sub heading. Nurra and Oyserman (2018) found that children who were primed to think of their adult selves as not being far away were more motivated. Their possible selves felt more achievable and thus were more motivating, than those who were primed to think of their adult selves as far away. :I discuss the findings in my chapter and I've included the resources below, if you'd like to check it out. :Nurra, C., & Oyserman, D. (2018). From future self to current action: An identity-based motivation perspective. ''Self and Identity, 17''(3), 343-364. https://doi.org/10.1080/15298868.2017.1375003 :Oyserman, D. (2024), Identity-based motivation and the motivational consequences of difficulty. ''Social and Personality Psychology Compass, 18'', e70028. https://doi.org/10.1111/spc3.70028 [[User:U3253363|U3253363]] ([[User talk:U3253363|discuss]] • [[Special:Contributions/U3253363|contribs]]) 03:29, 9 September 2026 (UTC) == Feedback on possible selves and goal pursuit == I found the distinction between hoped-for and feared possible selves really interesting, particularly how these future self-representations can influence goal pursuit. It could be useful to further emphasise how self-efficacy may determine whether imagining a possible self actually translates into motivated behaviour. This could help explain why having a desired future self does not always result in successful goal pursuit. [[User:U3188047|U3188047]] ([[User talk:U3188047|discuss]] • [[Special:Contributions/U3188047|contribs]]) 20:38, 27 August 2026 (UTC) <!-- Official topic development feedback --> {{METF/2026 |1= <!-- Title --> # Title and/or subtitle not correctly worded and/or didn't use [[w:Letter case#Sentence casing|sentence casing]] (fixed) |2= <!-- Headings --> # Each subheading should starts with a capital letter # Remove numbering from subheadings <!-- Heading structure --> <!-- 2-level --> # Excellent – Well developed [[Motivation and emotion/Assessment/Major project/Structure|2-level heading structure]]. Meaningful headings clearly relate directly to the core topic. <!-- Alignment with focus questions --> # Excellent alignment between sub-title, focus questions, and heading structure <!-- GenAI ---> # Are the headings based on [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, this needs to be acknowledged in the edit summaries, otherwise it violates academic integrity. |3= <!-- Overview--> # Excellent – Scenario, image, evocative description of the problem/topic, and focus questions <!-- Focus questions --> # Focus questions are aligned with sub-title and top-level headings |4= <!-- Key points--> <!-- Overall --> # Excellent – key points are well developed for each section # Provide more detailed edit summaries <!-- Scope --> <!-- Scope --> # The scope is excellent (i.e., not too little/narrow or too big/broad) <!-- Writing style --> # The writing style is clear and easy to follow <!-- Theory and research --> # Good balance of theory and research <!-- Conclusion --> # Conclusion is underway # What are the practical, take-home messages? (address the focus questions) |5= <!-- Figure --> # One relevant figure is presented and captioned <!-- Cite --> # Cite each figure at least once in the main text using APA style (e.g., see Figure 1) |6= <!-- Learning feature --> <!-- Interwiki links ---> # Add in-text [[m:Help:Interwiki linking|interwiki links]] for first mention of key terms to [[w:|Wikipedia]] and/or [[Motivation and emotion/Book|book chapters]] (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- Scenarios/examples/case studies --> # Consider use of more scenarios/examples/case studies <!-- Quiz --> # Consider including quiz question(s) about the take-home messages <!-- Tables --> # Also consider using tables to summarise key information |7= <!-- References --> <!-- Overall --> # Very good # Remove irrelevant references <!-- Systematic reviews --> # What are the most relevant systematic reviews/meta-analyses about this topic? <!-- APA style --> # Check and correct [https://apastyle.apa.org/instructional-aids/reference-guide.pdf APA referencing style]: ## [[Help:Wikitext quick reference|italicisation]] |8= <!-- Resources --> <!-- See also --> # See also ## One of two relevant link types provided ### Also link to related [[Motivation and emotion/Book|motivation and emotion book chapters]] ## Use alphabetical order <!-- External links --> # External links ## Very good ## Use alphabetical order |9= <!-- User page --> # Used effectively # Brief description about self – consider expanding <!-- Links to profile(s) --> # Consider linking to your [https://portfolio.canberra.edu.au/ eportfolio] page and/or any other professional online profile or resume such as [https://www.linkedin.com/ LinkedIn]. This is not required, but it can be useful to interlink your professional networks. <!-- Link to book chapter --> # A link to the book chapter is provided |10= <!-- Social contribution --> # Three different types of contributions with direct link(s) to evidence }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 07:57, 30 August 2026 (UTC) 59xtjfgq2q7j2rmybzaemhiueq5lhon 0 331638 2844924 2840030 2026-11-09T02:20:34Z Jtneill 10242 Copyediting 2844924 wikitext text/x-wiki {{title|Scarcity versus abundance mindset<br>How do scarcity and abundance mindsets develop and what are the motivational consequences?}} __TOC__ == Overview == {{RoundBoxTop|theme=3}} [[File:U3274291.png|right|500px|'''Figure 1'''. Urgent and competing goals in Alex’s week]] '''Case study — A crowded week''' Alex, a fictional university student, has rent due and two approaching assessment deadlines. An extra work shift would cover the rent but leave less study time. Alex checks the bank balance repeatedly and concentrates on tomorrow's assignment, overlooking next week's assessment. Figure 1 illustrates how one urgent problem can dominate competing goals. {{RoundBoxBottom}} Scarcity concerns the experience of having insufficient resources for important demands. It can redirect attention towards immediate needs while other goals receive less consideration (Shah et al., 2012). Understanding this process helps explain why someone can work intensely yet struggle with longer-term planning. This chapter examines how resource perceptions develop, their motivational and emotional consequences, and ways of supporting change. {{RoundBoxTop|theme=3}} '''Focus questions''' {{ic|Use bullet points as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} ·      What are scarcity and abundance mindsets? ·      How do these mindsets develop? ·      How do they influence motivation and emotion, and when is scarcity helpful or harmful? ·      Can scarcity-focused thinking be changed? {{RoundBoxBottom}} == Understanding scarcity and abundance mindsets == Resource conditions and interpretations must be distinguished {{vague}}. A shortage can be objectively measurable, such as insufficient income for housing, or experienced relative to personal needs and expectations {{vague}}. Someone with a comfortable income may still face severe time constraints. The resource, comparison standard and duration therefore need specification (Hamilton et al., 2019). === Scarcity and perceived sufficiency === A scarcity mindset describes attention and interpretation organized around a perceived resource shortfall. It should not be treated as a fixed personality type {{f}}. Research distinguishes immediate reactions, coping efforts and adaptations to continuing financial constraints (Hamilton et al., 2019). This {{what}} distinction allows the same person to respond differently across circumstances. An abundance mindset means perceived resource sufficiency: having enough usable resources to consider options beyond the immediate shortage {{f}}. This working definition is narrower than popular claims {{f}} about attracting success through positive thinking. Huijsmans et al. (2019) experimentally induced scarcity and abundance within {{who}} participants {{where}} and examined food-purchasing decisions using brain imaging. Their findings concern context-dependent decision processing, not proof that adopting an optimistic identity produces wealth or lasting wellbeing {{ic|What were the findings?}}. Most studies reviewed in this chapter concern financial scarcity, with fewer directly examining perceived abundance. Conclusions about time pressure or a lasting abundance orientation therefore need additional evidence. Absence of financial scarcity is not automatically the same as optimism, generosity or psychological wellbeing {{f}}. Keeping these concepts separate prevents a useful comparison from becoming an unsupported contrast between two kinds of people {{vague}}. Table 1 summarizes the distinction without dividing people into superior and inferior categories {{huh}}. These {{what}} are possible patterns, not diagnostic traits. A person may experience financial sufficiency alongside time scarcity, or alternate {{g}} between states as circumstances change. The comparison should therefore guide questions about context rather than judgements about character. '''Table 1''' ''Interpreting scarcity and resource sufficiency'' {| class="wikitable" |'''Dimension''' |'''Scarcity-focused state''' |'''Resource-sufficient state''' |- |Perception |Important demands exceed resources |Resources appear adequate for current demands |- |Possible priority |Resolve the urgent shortfall |Consider a wider range of goals |- |Potential benefit |Focus and careful trade-offs |Flexibility and room for planning |- |Caution |Neglected goals may carry costs |Sufficiency does not guarantee wise choices |} ''Note.'' Conceptual synthesis of Shah et al. (2012), Hamilton et al. (2019), and Huijsmans et al. (2019). === Explanatory frameworks === Scarcity theory {{f}} proposes that urgent shortages capture attention, producing ''tunnelling'': concentrated engagement with one problem and neglect of others. In resource-allocation experiments {{explain}}, Shah et al. (2012) found that having fewer resources altered attention and encouraged overborrowing. The motivational implication is selective effort rather than a simple absence of motivation {{explain}}. Experimental tasks establish mechanisms more clearly than they represent the complexity of everyday hardship. Conservation of resources theory places these experiences within a broader account of stress. People seek to protect and build valued resources, and threatened or actual losses can produce distress (Hobfoll, 1989). Applied to Alex, earning money consumes time needed for study, illustrating why protecting one resource can strain another. This framework addresses loss and protection, whereas scarcity theory specifies changes in attention {{f}}. Cannon et al. (2019) propose two routes of self-regulation: reducing the shortage or restoring control elsewhere. Which route is pursued depends partly on whether the resource gap seems changeable. For example, a student who sees a workable payment arrangement may seek it, while an apparently insoluble problem may redirect effort towards another manageable task. The model generates useful predictions, but a proposed pathway still requires evidence in each setting. The difference between these routes becomes clearer when considering what a behavior achieves. In a hypothetical example, Alex might reorganize a desk because this feels manageable, even though it does not resolve the rent shortfall. Cannon et al.'s (2019) model would invite questions about whether this restores a sense of control or helps reduce the shortage itself. Such an interpretation is a hypothesis rather than a diagnosis. It suggests that evaluating coping requires examining both its immediate emotional function and whether it helps the person address the resource problem over time. == How scarcity and abundance mindsets develop == Development {{ic|of what?}} involves current circumstances and previous experience. A temporary manipulation of resources can test immediate {{what}} responses, while childhood history research examines longer-term differences {{ic|in what?}}. These approaches answer different {{what}} questions and should not be treated as interchangeable evidence about lifelong personality. Figure 2 brings their proposed relationships together. [[File:U3274291..png|right|500x500px|thumb|'''Figure 2'''. Proposed pathways connecting resources and motivation'] ''Note.'' Original conceptual synthesis informed by Cannon et al. (2019), Hobfoll (1989), and Ryan and Deci (2000). Arrows indicate proposed relationships, not a validated causal model; effects depend on context. == Current demands and uncertainty == Actual shortages can create repeated decisions about which needs to meet. Haushofer and Fehr (2014) describe how poverty-related stress and negative emotion may influence choices, potentially contributing to continuing hardship. This {{what}} is a proposed feedback process involving circumstances and behavior. It does not imply that poverty originates in a defective mindset. Perceived control helps explain why the same shortage may produce different responses. Mittal and Griskevicius (2014) found {{how}} that uncertainty reduced perceived control more among {{who}} participants reporting poorer childhood environments; control statistically mediated differences in impulsive behavior {{g}}. Statistical mediation is consistent with an explanatory mechanism, but does not by itself establish the entire causal sequence. The findings suggest that expectations about whether effort will succeed deserve attention alongside resource levels. Comparisons with previous conditions can also matter {{vague}}. Huijsmans et al. (2019) observed differences between scarcity and abundance in{{who}} brain regions associated with valuation and goal-directed choice; {{what}} effects were particularly evident when scarcity followed abundance. This suggests that a change in resources may be experienced relative to what was available before. However, activity in a brain region does not establish a single psychological process, and the experiment concerned consumer choices rather than long-term motivation. === Earlier experiences and changing expectations === Drawing on life history theory, Griskevicius et al. (2013) examined responses to economic uncertainty in three experiments. {{ic|How many?}} Participants from poorer childhood backgrounds {{where}} showed greater impulsivity and risk-taking under threat, whereas those from wealthier backgrounds responded more cautiously. Earlier environments may influence how reliable future opportunities appear. However, retrospective childhood reports and short experimental tasks cannot establish a universal developmental pathway or predict an individual's choices. An account of resource sufficiency should similarly consider stability, usable support and expectations of future access. Predictable help may make planning more feasible even when resources remain modest. This is an application of the resource-protection and control frameworks, rather than evidence for a distinct, permanent abundance personality (Cannon et al., 2019; Hobfoll, 1989). Longitudinal research would be needed to establish how such expectations develop and persist. A useful developmental question is whether expectations change when circumstances improve. If Alex gains reliable support but still anticipates another shortage, following the student over several months could help distinguish continuing financial pressure from expectations carried forward from earlier experience. Researchers would need repeated measures of resources, perceived control and goal choices, rather than relying on one retrospective questionnaire. This proposed aproach follows the chapter's distinction between circumstances and interpretation. It would also allow examination of individual variation, including why similar improvements in resources might be followed by different patterns of planning. == Motivational and emotional consequences == Consequences depend on what is measured: effort towards an urgent goal, performance on an unrelated task, emotional experience or future-oriented choice. A finding in one domain cannot automatically explain another. The research below therefore separates selective benefits from potential costs and considers evidence that challenges broad conclusions. === Immediate focus and cognitive costs === Scarcity can improve attention to trade-offs. Shah et al. (2015) found {{how}} that resource constraints made some {{which}} judgements of value less susceptible to irrelevant contextual information. Pressing needs supplied a more consistent comparison standard. This challenges the assumption {{f}} that scarcity necessarily makes every decision less rational. Mani et al. (2013) reported poorer cognitive performance after financial concerns were prompted among lower-income participants {{where}}. They also observed the same farmers performing less well before harvest than afterwards. Within person comparisons reduce explanations based on stable individual differences, but seasonal comparisons cannot control every changing circumstance. The findings support a situational burden on performance, not the conclusion that people experiencing poverty have lower inherent intelligence. Attention may also be affected selectively, {{g}} Zhang et al. (2023) used a visual-search task and electroencephalography to distinguish target enhancement from distractor suppression. Scarcity induction was associated with poorer suppression of irrelevant information, while target enhancement remained relatively unchanged. This suggests that filtering distractions can be affected without every attentional process deteriorating, although laboratory effects require testing in everyday settings. The broader evidence is mixed, {{g}} Carvalho et al. (2016) randomly assigned low-income households to {{what}} assessment before or after payday and found no corresponding differences in cognitive performance or decision quality. Before-payday participants preferred earlier monetary rewards, but not earlier rewards involving real effort. An immediate need for cash can therefore resemble impatience without demonstrating a general motivational deficit. In a meta-analysis of 29 studies, de Almeida et al. (2024) reported an overall negative association between financial scarcity and cognitive performance. The estimated effect became substantially smaller after accounting for education. Education may share causes with scarcity or form part of its longer-term consequences, so statistical adjustment alone does not identify the causal explanation. Combining different designs also cannot establish that every short-term scarcity manipulation has the same effect. Szecsi and Szaszi (2024) addressed a narrower question: whether financial-scarcity cues disproportionately impair poorer participants' cognitive performance. Their Bayesian meta-analysis of 10 studies found limited, uncertain evidence and a small estimated effect. Similar study designs and incomplete moderator information restricted generalization. These findings caution against a universal claim that scarcity reduces mental capacity. A later systematic review examined changes in actual financial resources rather than scarcity reminders. Szecsi et al. (2025) synthesized 14 studies and found inconclusive evidence for improved cognitive performance, with any positive average effect likely to be small. This distinction matters because receiving resources and thinking about shortage are different interventions. Material support can still improve living conditions even when cognitive-test gains are uncertain. These disagreements also affect how motivation should be measured. A cognitive task assesses performance under particular conditions; it does not directly show whether someone values a goal, persists with it or experiences their effort as worthwhile. Future studies could assess these outcomes together while distinguishing temporary cash shortages from enduring disadvantage. For example, a student might maintain test performance but abandon an important activity because paid work takes priority. This hypothetical pattern would indicate a change in goal allocation, even without a measurable cognitive decline, and would require an explanation beyond test scores alone. === Emotion and the quality of motivation === Emotional strain is relevant even when cognitive-test effects are absent. Haushofer and Fehr (2014) identify stress and negative affect as possible links between poverty and economic behavior. Adamkovič and Martončik (2017) integrate cognitive load, executive functioning and decision processes in a proposed model. Their synthesis makes the relationships explicit, but does not establish that every link occurs together or that emotional strain inevitably produces poor choices. Self-determination theory asks what kind of motivation sustains behavior. Autonomy involves experiencing choice, competence involves feeling effective, and relatedness concerns connection with others (Ryan & Deci, 2000). A student may expend substantial effort because of pressure while losing interest in learning. Applied here, the distinction separates the amount of effort from its psychological quality. Deci and Ryan (2000) distinguish the content of goals from the reasons for pursuing them. Meeting rent is an external outcome, but working towards it may still be personally endorsed rather than entirely imposed. Consequently, financial goals should not automatically be labelled unhealthy or inferior. Understanding motivation requires examining whether the person experiences agency and whether important psychological needs are supported. Evidence also challenges the idea that material deprivation eliminates intrinsic motivation. Research by van Egmond et al. (2017) found that intrinsic motivation predicted school attendance under severe resource scarcity, and basic-need satisfaction was particularly important under greater deprivation. These findings support attending to psychological needs alongside material conditions. They do not show that encouragement can replace food, transport or financial support. {{ic|Explain how this relates to abundance/scarcity mindset.}} Fredrickson's (2001) broaden-and-build theory proposes that positive emotions can widen the range of thoughts and actions considered and help build resources over time. It offers a possible explanation for exploration when circumstances feel safer. However, positive emotion and perceived abundance are different constructs. Evidence for one should not be presented as direct validation of the other. Self-determination theory also clarifies why receiving help need not undermine autonomy. Autonomy concerns acting with personal endorsement, rather than completing everything independently (Ryan & Deci, 2000). Alex could therefore accept financial or academic assistance while retaining a meaningful role in choosing the next steps. In contrast, assistance accompanied by pressure to follow someone else's priorities might leave little room for endorsement. Applied to scarcity, this distinction suggests evaluating how support is offered as well as what resources it supplies. The proposed benefit is more sustainable engagement with valued goals, not simply greater compliance with external expectations. === Social priorities and interpreting evidence === Scarcity does not determine a person's generosity. Roux et al. (2015) found that scarcity reminders encouraged a competitive orientation, which could support self-interested behavior or generosity when helping also offered personal benefits. The motivational context mattered. Such experiments cannot justify character judgements about all people with low incomes. Laforet et al. (2024) found that focusing on motives beyond personal benefit encouraged broader thinking and other-oriented intentions under perceived scarcity. This provides a counterpoint to accounts of unavoidable self-focus. However, intentions to help are not equivalent to sustained helping, and student samples limit generalization. Both findings suggest that social goals can remain responsive to context. The review by de Bruijn and Antonides (2022) concludes that scarcity theory is useful but does not fully match the evidence. Income, subjective shortage and experimental resource restrictions are often treated as equivalent despite measuring different things. For this chapter, the strongest interpretation is that resource conditions can redirect motivation through several pathways. The size, persistence and practical importance of each effect remain empirical questions. These frameworks can be integrated without treating them as interchangeable. In Alex’s case, scarcity theory concerns which deadline attracts attention, conservation of resources theory concerns the strain of exchanging study time for income, and self-determination theory concerns whether study feels chosen and achievable. Their combination predicts that improving finances could ease one burden while leaving motivation affected by an unsupportive learning environment. This is a theory-informed interpretation, not a finding directly tested with Alex (Hobfoll, 1989; Ryan & Deci, 2000; Shah et al., 2012). A useful evaluation would therefore examine competing goals, emotional strain and perceived agency separately. == Can scarcity-focused thinking be changed? == Change {{ic|of what?}} should address the shortage {{ic|of what}} and the conditions surrounding decisions. Practical recommendations need to distinguish tested interventions from reasonable applications of theory. A positive message may feel supportive while leaving the original barrier untouched. The following approaches combine material support with opportunities for more manageable goal pursuit. === Reduce shortages and decision burdens === Haushofer and Shapiro (2016) tested unconditional cash transfers in rural Kenya using random assignment. Recipients experienced improvements in economic outcomes and psychological wellbeing, although there was no overall effect on cortisol. This supports changing material conditions as a route to improvement. It does not isolate an abundance mindset as the mechanism or establish identical effects in other populations. Ong et al. (2019) studied a debt-relief program in Singapore. Improvements in psychological functioning were associated with relief, and clearing more debt accounts mattered beyond the amount repaid. This suggests that juggling separate obligations can create burdens of its own. Because the study was quasi-experimental, its design leaves more uncertainty than random assignment about alternative explanations. Time also deserves attention. Whillans et al. (2017) combined surveys with an experiment in which working adults reported greater happiness after a time-saving purchase than a material purchase. The result supports treating time pressure as a meaningful concern. It is not an affordable solution for everyone, so practical applications might instead consider accessible help or realistic workload adjustments; those alternatives require their own evaluation. The intervention findings raise a further question about what counts as success. Improved living conditions, reduced distress and better cognitive performance are separate outcomes, so evidence for one should not substitute for evidence about another (Haushofer & Shapiro, 2016; Szecsi et al., 2025). A program could be valuable because it makes housing more secure even if cognitive scores remain unchanged. Conversely, an improvement on a brief task would not establish that everyday financial pressures had disappeared. Evaluations should therefore specify their intended outcome and examine whether benefits persist beyond the immediate assessment period. === Support agency and broader goals === Psychological support can complement practical relief. Offering meaningful choices, achievable tasks and respectful assistance follows self-determination theory, while preserving the person's involvement in decisions (Ryan & Deci, 2000). For a student, this might mean choosing a study sequence with a tutor rather than receiving another demand to work harder. These are theory-informed applications, not a tested package for producing an abundance mindset. '''Case study — A more manageable week''' Alex contacts student support, arranges a feasible payment plan and discusses the assessment workload with a tutor. A calendar now includes the later assignment and recovery time. Financial pressure remains, but there is a clearer next step and less uncertainty. This fictional outcome illustrates possible support; it is not evidence that these actions guarantee improvement. {{ic|More impoortantly, in the context of this chapter, have these material changes had any effect on mindset?}} Reflection can help identify which resource is actually scarce and which concern is dominating attention. A useful question is whether a decision addresses an immediate need while overlooking another important goal. Another is whether practical help would make a delayed goal more feasible. These prompts apply the chapter's frameworks without assuming that reframing alone removes hardship. For Alex, this evaluation could involve reviewing the following week rather than judging success from an immediate feeling of relief. Did the payment arrangement reduce the urgent shortfall, and was there enough time to begin the later assignment? If the arrangement required extra work shifts that displaced study again, the original conflict would remain. Revising the plan would then be a response to its practical limits. This extension of the fictional case shows why progress should be assessed across competing goals, with attention to remaining barriers rather than an assumption that a positive outlook has solved them. '''Applying the ideas''' Consider a person who repeatedly postpones a goal. Identify the missing resource: money, time, reliable support or something else. Separate the immediate obligation from the goal that is being overlooked, then identify one feasible source of practical assistance. Review whether the change actually improves functioning, such as starting the delayed task or protecting recovery time. This reflection is a learning exercise, not a validated intervention or a test of whether someone has the correct mindset. == Conclusion == Scarcity-focused thinking develops through interactions between current demands, perceived control and earlier experiences. It can strengthen immediate focus and trade-off awareness, while making competing goals harder to manage. Emotional strain and motivational quality matter alongside cognitive performance, and effects vary across methods and circumstances. Resource sufficiency is best treated here as a contextual perception, rather than a universally beneficial personality type. Improving motivational and emotional lives therefore involves identifying actual shortages, reducing avoidable burdens and supporting agency and connection. The research gives stronger grounds for specific, evaluated forms of support than for promises attached to an abundance label. For Alex, the practical aim is sustainable progress across important goals. Success should be judged by functioning and wellbeing, not by whether someone sounds sufficiently positive. == See also == {{ic|Use bullet points as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} ·      Scarcity (Wikipedia) ·      Self-determination theory (Wikipedia) ·      [[Motivation and emotion/Book/2025/Autonomy and intrinsic motivation in self-determination theory|Autonomy and intrinsic motivation in self-determination theory]] (Wikiversity) == References == {{Hanging indent|1= Adamkovič, M., & Martončik, M. (2017). A review of consequences of poverty on economic decision-making: A hypothesized model of a cognitive mechanism. ''Frontiers in Psychology, 8'', Article 1784. <nowiki>https://doi.org/10.3389/fpsyg.2017.01784</nowiki> Cannon, C., Goldsmith, K., & Roux, C. (2019). A self-regulatory model of resource scarcity. ''Journal of Consumer Psychology, 29''(1), 104–127. <nowiki>https://doi.org/10.1002/jcpy.1035</nowiki> Carvalho, L. 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(2001). The role of positive emotions in positive psychology: The broaden-and-build theory of positive emotions. ''American Psychologist, 56''(3), 218–226. <nowiki>https://doi.org/10.1037/0003-066X.56.3.218</nowiki> Griskevicius, V., Ackerman, J. M., Cantú, S. M., Delton, A. W., Robertson, T. E., Simpson, J. A., Emery Thompson, M., & Tybur, J. M. (2013). When the economy falters, do people spend or save? Responses to resource scarcity depend on childhood environments. ''Psychological Science, 24''(2), 197–205. <nowiki>https://doi.org/10.1177/0956797612451471</nowiki> Hamilton, R. W., Mittal, C., Shah, A., Thompson, D. V., & Griskevicius, V. (2019). How financial constraints influence consumer behavior: An integrative framework. ''Journal of Consumer Psychology, 29''(2), 285–305. <nowiki>https://doi.org/10.1002/jcpy.1074</nowiki> Haushofer, J., & Fehr, E. (2014). On the psychology of poverty. ''Science, 344''(6186), 862–867. <nowiki>https://doi.org/10.1126/science.1232491</nowiki> Haushofer, J., & Shapiro, J. (2016). The short-term impact of unconditional cash transfers to the poor: Experimental evidence from Kenya. ''The Quarterly Journal of Economics, 131''(4), 1973–2042. <nowiki>https://doi.org/10.1093/qje/qjw025</nowiki> Hobfoll, S. E. (1989). Conservation of resources: A new attempt at conceptualizing stress. ''American Psychologist, 44''(3), 513–524. <nowiki>https://doi.org/10.1037/0003-066X.44.3.513</nowiki> Huijsmans, I., Ma, I., Micheli, L., Civai, C., Stallen, M., & Sanfey, A. G. (2019). A scarcity mindset alters neural processing underlying consumer decision making. ''Proceedings of the National Academy of Sciences, 116''(24), 11699–11704. <nowiki>https://doi.org/10.1073/pnas.1818572116</nowiki> Laforet, B., Carrera, P., & Caballero, A. (2024). Breaking self-focused orientation in people who perceive economic scarcity: The influence of transcendent motivation to promote an abstract mindset and prosocial behavioral intentions. ''Scandinavian Journal of Psychology, 65''(4), 607–616. <nowiki>https://doi.org/10.1111/sjop.13009</nowiki> Mani, A., Mullainathan, S., Shafir, E., & Zhao, J. (2013). Poverty impedes cognitive function. ''Science, 341''(6149), 976–980. <nowiki>https://doi.org/10.1126/science.1238041</nowiki> Mittal, C., & Griskevicius, V. (2014). Sense of control under uncertainty depends on people's childhood environment: A life history theory approach. ''Journal of Personality and Social Psychology, 107''(4), 621–637. <nowiki>https://doi.org/10.1037/a0037398</nowiki> Ong, Q., Theseira, W., & Ng, I. Y. H. (2019). Reducing debt improves psychological functioning and changes decision-making in the poor. ''Proceedings of the National Academy of Sciences, 116''(15), 7244–7249. <nowiki>https://doi.org/10.1073/pnas.1810901116</nowiki> Roux, C., Goldsmith, K., & Bonezzi, A. (2015). On the psychology of scarcity: When reminders of resource scarcity promote selfish (and generous) behavior. ''Journal of Consumer Research, 42''(4), 615–631. <nowiki>https://doi.org/10.1093/jcr/ucv048</nowiki> Ryan, R. M., & Deci, E. L. (2000). Self-determination theory and the facilitation of intrinsic motivation, social development, and well-being. ''American Psychologist, 55''(1), 68–78. <nowiki>https://doi.org/10.1037/0003-066X.55.1.68</nowiki> Shah, A. K., Mullainathan, S., & Shafir, E. (2012). Some consequences of having too little. ''Science, 338''(6107), 682–685. <nowiki>https://doi.org/10.1126/science.1222426</nowiki> Shah, A. K., Shafir, E., & Mullainathan, S. (2015). Scarcity frames value. ''Psychological Science, 26''(4), 402–412. <nowiki>https://doi.org/10.1177/0956797614563958</nowiki> Szecsi, P., Kolumban, P., Taka, A., & Szaszi, B. (2025). The impact of financial resources on cognitive performance: A systematic review and meta-analysis. ''Collabra: Psychology, 11''(1), Article 147236. <nowiki>https://doi.org/10.1525/collabra.147236</nowiki> Szecsi, P., & Szaszi, B. (2024). Financial-scarcity-related cues’ impact on the cognitive performance of the poor: A meta-analysis. ''Collabra: Psychology, 10''(1), Article 122943. <nowiki>https://doi.org/10.1525/collabra.122943</nowiki> van Egmond, M. C., Navarrete Berges, A., Omarshah, T., & Benton, J. (2017). The role of intrinsic motivation and the satisfaction of basic psychological needs under conditions of severe resource scarcity. ''Psychological Science, 28''(6), 822–828. <nowiki>https://doi.org/10.1177/0956797617698138</nowiki> Whillans, A. V., Dunn, E. W., Smeets, P., Bekkers, R., & Norton, M. I. (2017). Buying time promotes happiness. ''Proceedings of the National Academy of Sciences, 114''(32), 8523–8527. <nowiki>https://doi.org/10.1073/pnas.1706541114</nowiki> Zhang, L., Xu, M., Du, X., Yang, Q., & Qiao, L. (2023). Scarcity mindset impairs distractor suppression but not target enhancement in selective attention: Evidence from ERPs. ''Neuropsychologia, 191'', Article 108739. <nowiki>https://doi.org/10.1016/j.neuropsychologia.2023.108739</nowiki> }} == External links == {{ic|Use bullet points as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} [https://The&#x20;psychology&#x20;of&#x20;scarcity&#x20;(American&#x20;Psychological&#x20;Association) ·      The psychology of scarcity (American Psychological Association)] [https://Overview&#x20;of&#x20;self-determination&#x20;theory&#x20;(Center&#x20;for&#x20;Self-Determination&#x20;Theory) ·      Overview of self-determination theory (Center for Self-Determination Theory)] [https://To&#x20;promote&#x20;happiness,&#x20;choose&#x20;time&#x20;over&#x20;money&#x20;(Whillans&#x20;and&#x20;Dunn,&#x20;Behavioral&#x20;Scientist ·      To promote happiness, choose time over money (Whillans and Dunn, Behavioral Scientist] [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Mindset/Scarcity]] p4wnpxf80m0q7zc7w2nviapfyu77mgo 2844926 2844924 2026-11-09T03:08:14Z Davey2010 291715 ([[c:GR|GR]]) [[c:COM:FR|File renamed]]: [[File:U3274291.png]] → [[File:Urgent and competing goals influence attention.png]] [[c:COM:FR#FR2|Criterion 2]] (meaningless or ambiguous name) 2844926 wikitext text/x-wiki {{title|Scarcity versus abundance mindset<br>How do scarcity and abundance mindsets develop and what are the motivational consequences?}} __TOC__ == Overview == {{RoundBoxTop|theme=3}} [[File:Urgent and competing goals influence attention.png|right|500px|'''Figure 1'''. Urgent and competing goals in Alex’s week]] '''Case study — A crowded week''' Alex, a fictional university student, has rent due and two approaching assessment deadlines. An extra work shift would cover the rent but leave less study time. Alex checks the bank balance repeatedly and concentrates on tomorrow's assignment, overlooking next week's assessment. Figure 1 illustrates how one urgent problem can dominate competing goals. {{RoundBoxBottom}} Scarcity concerns the experience of having insufficient resources for important demands. It can redirect attention towards immediate needs while other goals receive less consideration (Shah et al., 2012). Understanding this process helps explain why someone can work intensely yet struggle with longer-term planning. This chapter examines how resource perceptions develop, their motivational and emotional consequences, and ways of supporting change. {{RoundBoxTop|theme=3}} '''Focus questions''' {{ic|Use bullet points as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} ·      What are scarcity and abundance mindsets? ·      How do these mindsets develop? ·      How do they influence motivation and emotion, and when is scarcity helpful or harmful? ·      Can scarcity-focused thinking be changed? {{RoundBoxBottom}} == Understanding scarcity and abundance mindsets == Resource conditions and interpretations must be distinguished {{vague}}. A shortage can be objectively measurable, such as insufficient income for housing, or experienced relative to personal needs and expectations {{vague}}. Someone with a comfortable income may still face severe time constraints. The resource, comparison standard and duration therefore need specification (Hamilton et al., 2019). === Scarcity and perceived sufficiency === A scarcity mindset describes attention and interpretation organized around a perceived resource shortfall. It should not be treated as a fixed personality type {{f}}. Research distinguishes immediate reactions, coping efforts and adaptations to continuing financial constraints (Hamilton et al., 2019). This {{what}} distinction allows the same person to respond differently across circumstances. An abundance mindset means perceived resource sufficiency: having enough usable resources to consider options beyond the immediate shortage {{f}}. This working definition is narrower than popular claims {{f}} about attracting success through positive thinking. Huijsmans et al. (2019) experimentally induced scarcity and abundance within {{who}} participants {{where}} and examined food-purchasing decisions using brain imaging. Their findings concern context-dependent decision processing, not proof that adopting an optimistic identity produces wealth or lasting wellbeing {{ic|What were the findings?}}. Most studies reviewed in this chapter concern financial scarcity, with fewer directly examining perceived abundance. Conclusions about time pressure or a lasting abundance orientation therefore need additional evidence. Absence of financial scarcity is not automatically the same as optimism, generosity or psychological wellbeing {{f}}. Keeping these concepts separate prevents a useful comparison from becoming an unsupported contrast between two kinds of people {{vague}}. Table 1 summarizes the distinction without dividing people into superior and inferior categories {{huh}}. These {{what}} are possible patterns, not diagnostic traits. A person may experience financial sufficiency alongside time scarcity, or alternate {{g}} between states as circumstances change. The comparison should therefore guide questions about context rather than judgements about character. '''Table 1''' ''Interpreting scarcity and resource sufficiency'' {| class="wikitable" |'''Dimension''' |'''Scarcity-focused state''' |'''Resource-sufficient state''' |- |Perception |Important demands exceed resources |Resources appear adequate for current demands |- |Possible priority |Resolve the urgent shortfall |Consider a wider range of goals |- |Potential benefit |Focus and careful trade-offs |Flexibility and room for planning |- |Caution |Neglected goals may carry costs |Sufficiency does not guarantee wise choices |} ''Note.'' Conceptual synthesis of Shah et al. (2012), Hamilton et al. (2019), and Huijsmans et al. (2019). === Explanatory frameworks === Scarcity theory {{f}} proposes that urgent shortages capture attention, producing ''tunnelling'': concentrated engagement with one problem and neglect of others. In resource-allocation experiments {{explain}}, Shah et al. (2012) found that having fewer resources altered attention and encouraged overborrowing. The motivational implication is selective effort rather than a simple absence of motivation {{explain}}. Experimental tasks establish mechanisms more clearly than they represent the complexity of everyday hardship. Conservation of resources theory places these experiences within a broader account of stress. People seek to protect and build valued resources, and threatened or actual losses can produce distress (Hobfoll, 1989). Applied to Alex, earning money consumes time needed for study, illustrating why protecting one resource can strain another. This framework addresses loss and protection, whereas scarcity theory specifies changes in attention {{f}}. Cannon et al. (2019) propose two routes of self-regulation: reducing the shortage or restoring control elsewhere. Which route is pursued depends partly on whether the resource gap seems changeable. For example, a student who sees a workable payment arrangement may seek it, while an apparently insoluble problem may redirect effort towards another manageable task. The model generates useful predictions, but a proposed pathway still requires evidence in each setting. The difference between these routes becomes clearer when considering what a behavior achieves. In a hypothetical example, Alex might reorganize a desk because this feels manageable, even though it does not resolve the rent shortfall. Cannon et al.'s (2019) model would invite questions about whether this restores a sense of control or helps reduce the shortage itself. Such an interpretation is a hypothesis rather than a diagnosis. It suggests that evaluating coping requires examining both its immediate emotional function and whether it helps the person address the resource problem over time. == How scarcity and abundance mindsets develop == Development {{ic|of what?}} involves current circumstances and previous experience. A temporary manipulation of resources can test immediate {{what}} responses, while childhood history research examines longer-term differences {{ic|in what?}}. These approaches answer different {{what}} questions and should not be treated as interchangeable evidence about lifelong personality. Figure 2 brings their proposed relationships together. [[File:U3274291..png|right|500x500px|thumb|'''Figure 2'''. Proposed pathways connecting resources and motivation'] ''Note.'' Original conceptual synthesis informed by Cannon et al. (2019), Hobfoll (1989), and Ryan and Deci (2000). Arrows indicate proposed relationships, not a validated causal model; effects depend on context. == Current demands and uncertainty == Actual shortages can create repeated decisions about which needs to meet. Haushofer and Fehr (2014) describe how poverty-related stress and negative emotion may influence choices, potentially contributing to continuing hardship. This {{what}} is a proposed feedback process involving circumstances and behavior. It does not imply that poverty originates in a defective mindset. Perceived control helps explain why the same shortage may produce different responses. Mittal and Griskevicius (2014) found {{how}} that uncertainty reduced perceived control more among {{who}} participants reporting poorer childhood environments; control statistically mediated differences in impulsive behavior {{g}}. Statistical mediation is consistent with an explanatory mechanism, but does not by itself establish the entire causal sequence. The findings suggest that expectations about whether effort will succeed deserve attention alongside resource levels. Comparisons with previous conditions can also matter {{vague}}. Huijsmans et al. (2019) observed differences between scarcity and abundance in{{who}} brain regions associated with valuation and goal-directed choice; {{what}} effects were particularly evident when scarcity followed abundance. This suggests that a change in resources may be experienced relative to what was available before. However, activity in a brain region does not establish a single psychological process, and the experiment concerned consumer choices rather than long-term motivation. === Earlier experiences and changing expectations === Drawing on life history theory, Griskevicius et al. (2013) examined responses to economic uncertainty in three experiments. {{ic|How many?}} Participants from poorer childhood backgrounds {{where}} showed greater impulsivity and risk-taking under threat, whereas those from wealthier backgrounds responded more cautiously. Earlier environments may influence how reliable future opportunities appear. However, retrospective childhood reports and short experimental tasks cannot establish a universal developmental pathway or predict an individual's choices. An account of resource sufficiency should similarly consider stability, usable support and expectations of future access. Predictable help may make planning more feasible even when resources remain modest. This is an application of the resource-protection and control frameworks, rather than evidence for a distinct, permanent abundance personality (Cannon et al., 2019; Hobfoll, 1989). Longitudinal research would be needed to establish how such expectations develop and persist. A useful developmental question is whether expectations change when circumstances improve. If Alex gains reliable support but still anticipates another shortage, following the student over several months could help distinguish continuing financial pressure from expectations carried forward from earlier experience. Researchers would need repeated measures of resources, perceived control and goal choices, rather than relying on one retrospective questionnaire. This proposed aproach follows the chapter's distinction between circumstances and interpretation. It would also allow examination of individual variation, including why similar improvements in resources might be followed by different patterns of planning. == Motivational and emotional consequences == Consequences depend on what is measured: effort towards an urgent goal, performance on an unrelated task, emotional experience or future-oriented choice. A finding in one domain cannot automatically explain another. The research below therefore separates selective benefits from potential costs and considers evidence that challenges broad conclusions. === Immediate focus and cognitive costs === Scarcity can improve attention to trade-offs. Shah et al. (2015) found {{how}} that resource constraints made some {{which}} judgements of value less susceptible to irrelevant contextual information. Pressing needs supplied a more consistent comparison standard. This challenges the assumption {{f}} that scarcity necessarily makes every decision less rational. Mani et al. (2013) reported poorer cognitive performance after financial concerns were prompted among lower-income participants {{where}}. They also observed the same farmers performing less well before harvest than afterwards. Within person comparisons reduce explanations based on stable individual differences, but seasonal comparisons cannot control every changing circumstance. The findings support a situational burden on performance, not the conclusion that people experiencing poverty have lower inherent intelligence. Attention may also be affected selectively, {{g}} Zhang et al. (2023) used a visual-search task and electroencephalography to distinguish target enhancement from distractor suppression. Scarcity induction was associated with poorer suppression of irrelevant information, while target enhancement remained relatively unchanged. This suggests that filtering distractions can be affected without every attentional process deteriorating, although laboratory effects require testing in everyday settings. The broader evidence is mixed, {{g}} Carvalho et al. (2016) randomly assigned low-income households to {{what}} assessment before or after payday and found no corresponding differences in cognitive performance or decision quality. Before-payday participants preferred earlier monetary rewards, but not earlier rewards involving real effort. An immediate need for cash can therefore resemble impatience without demonstrating a general motivational deficit. In a meta-analysis of 29 studies, de Almeida et al. (2024) reported an overall negative association between financial scarcity and cognitive performance. The estimated effect became substantially smaller after accounting for education. Education may share causes with scarcity or form part of its longer-term consequences, so statistical adjustment alone does not identify the causal explanation. Combining different designs also cannot establish that every short-term scarcity manipulation has the same effect. Szecsi and Szaszi (2024) addressed a narrower question: whether financial-scarcity cues disproportionately impair poorer participants' cognitive performance. Their Bayesian meta-analysis of 10 studies found limited, uncertain evidence and a small estimated effect. Similar study designs and incomplete moderator information restricted generalization. These findings caution against a universal claim that scarcity reduces mental capacity. A later systematic review examined changes in actual financial resources rather than scarcity reminders. Szecsi et al. (2025) synthesized 14 studies and found inconclusive evidence for improved cognitive performance, with any positive average effect likely to be small. This distinction matters because receiving resources and thinking about shortage are different interventions. Material support can still improve living conditions even when cognitive-test gains are uncertain. These disagreements also affect how motivation should be measured. A cognitive task assesses performance under particular conditions; it does not directly show whether someone values a goal, persists with it or experiences their effort as worthwhile. Future studies could assess these outcomes together while distinguishing temporary cash shortages from enduring disadvantage. For example, a student might maintain test performance but abandon an important activity because paid work takes priority. This hypothetical pattern would indicate a change in goal allocation, even without a measurable cognitive decline, and would require an explanation beyond test scores alone. === Emotion and the quality of motivation === Emotional strain is relevant even when cognitive-test effects are absent. Haushofer and Fehr (2014) identify stress and negative affect as possible links between poverty and economic behavior. Adamkovič and Martončik (2017) integrate cognitive load, executive functioning and decision processes in a proposed model. Their synthesis makes the relationships explicit, but does not establish that every link occurs together or that emotional strain inevitably produces poor choices. Self-determination theory asks what kind of motivation sustains behavior. Autonomy involves experiencing choice, competence involves feeling effective, and relatedness concerns connection with others (Ryan & Deci, 2000). A student may expend substantial effort because of pressure while losing interest in learning. Applied here, the distinction separates the amount of effort from its psychological quality. Deci and Ryan (2000) distinguish the content of goals from the reasons for pursuing them. Meeting rent is an external outcome, but working towards it may still be personally endorsed rather than entirely imposed. Consequently, financial goals should not automatically be labelled unhealthy or inferior. Understanding motivation requires examining whether the person experiences agency and whether important psychological needs are supported. Evidence also challenges the idea that material deprivation eliminates intrinsic motivation. Research by van Egmond et al. (2017) found that intrinsic motivation predicted school attendance under severe resource scarcity, and basic-need satisfaction was particularly important under greater deprivation. These findings support attending to psychological needs alongside material conditions. They do not show that encouragement can replace food, transport or financial support. {{ic|Explain how this relates to abundance/scarcity mindset.}} Fredrickson's (2001) broaden-and-build theory proposes that positive emotions can widen the range of thoughts and actions considered and help build resources over time. It offers a possible explanation for exploration when circumstances feel safer. However, positive emotion and perceived abundance are different constructs. Evidence for one should not be presented as direct validation of the other. Self-determination theory also clarifies why receiving help need not undermine autonomy. Autonomy concerns acting with personal endorsement, rather than completing everything independently (Ryan & Deci, 2000). Alex could therefore accept financial or academic assistance while retaining a meaningful role in choosing the next steps. In contrast, assistance accompanied by pressure to follow someone else's priorities might leave little room for endorsement. Applied to scarcity, this distinction suggests evaluating how support is offered as well as what resources it supplies. The proposed benefit is more sustainable engagement with valued goals, not simply greater compliance with external expectations. === Social priorities and interpreting evidence === Scarcity does not determine a person's generosity. Roux et al. (2015) found that scarcity reminders encouraged a competitive orientation, which could support self-interested behavior or generosity when helping also offered personal benefits. The motivational context mattered. Such experiments cannot justify character judgements about all people with low incomes. Laforet et al. (2024) found that focusing on motives beyond personal benefit encouraged broader thinking and other-oriented intentions under perceived scarcity. This provides a counterpoint to accounts of unavoidable self-focus. However, intentions to help are not equivalent to sustained helping, and student samples limit generalization. Both findings suggest that social goals can remain responsive to context. The review by de Bruijn and Antonides (2022) concludes that scarcity theory is useful but does not fully match the evidence. Income, subjective shortage and experimental resource restrictions are often treated as equivalent despite measuring different things. For this chapter, the strongest interpretation is that resource conditions can redirect motivation through several pathways. The size, persistence and practical importance of each effect remain empirical questions. These frameworks can be integrated without treating them as interchangeable. In Alex’s case, scarcity theory concerns which deadline attracts attention, conservation of resources theory concerns the strain of exchanging study time for income, and self-determination theory concerns whether study feels chosen and achievable. Their combination predicts that improving finances could ease one burden while leaving motivation affected by an unsupportive learning environment. This is a theory-informed interpretation, not a finding directly tested with Alex (Hobfoll, 1989; Ryan & Deci, 2000; Shah et al., 2012). A useful evaluation would therefore examine competing goals, emotional strain and perceived agency separately. == Can scarcity-focused thinking be changed? == Change {{ic|of what?}} should address the shortage {{ic|of what}} and the conditions surrounding decisions. Practical recommendations need to distinguish tested interventions from reasonable applications of theory. A positive message may feel supportive while leaving the original barrier untouched. The following approaches combine material support with opportunities for more manageable goal pursuit. === Reduce shortages and decision burdens === Haushofer and Shapiro (2016) tested unconditional cash transfers in rural Kenya using random assignment. Recipients experienced improvements in economic outcomes and psychological wellbeing, although there was no overall effect on cortisol. This supports changing material conditions as a route to improvement. It does not isolate an abundance mindset as the mechanism or establish identical effects in other populations. Ong et al. (2019) studied a debt-relief program in Singapore. Improvements in psychological functioning were associated with relief, and clearing more debt accounts mattered beyond the amount repaid. This suggests that juggling separate obligations can create burdens of its own. Because the study was quasi-experimental, its design leaves more uncertainty than random assignment about alternative explanations. Time also deserves attention. Whillans et al. (2017) combined surveys with an experiment in which working adults reported greater happiness after a time-saving purchase than a material purchase. The result supports treating time pressure as a meaningful concern. It is not an affordable solution for everyone, so practical applications might instead consider accessible help or realistic workload adjustments; those alternatives require their own evaluation. The intervention findings raise a further question about what counts as success. Improved living conditions, reduced distress and better cognitive performance are separate outcomes, so evidence for one should not substitute for evidence about another (Haushofer & Shapiro, 2016; Szecsi et al., 2025). A program could be valuable because it makes housing more secure even if cognitive scores remain unchanged. Conversely, an improvement on a brief task would not establish that everyday financial pressures had disappeared. Evaluations should therefore specify their intended outcome and examine whether benefits persist beyond the immediate assessment period. === Support agency and broader goals === Psychological support can complement practical relief. Offering meaningful choices, achievable tasks and respectful assistance follows self-determination theory, while preserving the person's involvement in decisions (Ryan & Deci, 2000). For a student, this might mean choosing a study sequence with a tutor rather than receiving another demand to work harder. These are theory-informed applications, not a tested package for producing an abundance mindset. '''Case study — A more manageable week''' Alex contacts student support, arranges a feasible payment plan and discusses the assessment workload with a tutor. A calendar now includes the later assignment and recovery time. Financial pressure remains, but there is a clearer next step and less uncertainty. This fictional outcome illustrates possible support; it is not evidence that these actions guarantee improvement. {{ic|More impoortantly, in the context of this chapter, have these material changes had any effect on mindset?}} Reflection can help identify which resource is actually scarce and which concern is dominating attention. A useful question is whether a decision addresses an immediate need while overlooking another important goal. Another is whether practical help would make a delayed goal more feasible. These prompts apply the chapter's frameworks without assuming that reframing alone removes hardship. For Alex, this evaluation could involve reviewing the following week rather than judging success from an immediate feeling of relief. Did the payment arrangement reduce the urgent shortfall, and was there enough time to begin the later assignment? If the arrangement required extra work shifts that displaced study again, the original conflict would remain. Revising the plan would then be a response to its practical limits. This extension of the fictional case shows why progress should be assessed across competing goals, with attention to remaining barriers rather than an assumption that a positive outlook has solved them. '''Applying the ideas''' Consider a person who repeatedly postpones a goal. Identify the missing resource: money, time, reliable support or something else. Separate the immediate obligation from the goal that is being overlooked, then identify one feasible source of practical assistance. Review whether the change actually improves functioning, such as starting the delayed task or protecting recovery time. This reflection is a learning exercise, not a validated intervention or a test of whether someone has the correct mindset. == Conclusion == Scarcity-focused thinking develops through interactions between current demands, perceived control and earlier experiences. It can strengthen immediate focus and trade-off awareness, while making competing goals harder to manage. Emotional strain and motivational quality matter alongside cognitive performance, and effects vary across methods and circumstances. Resource sufficiency is best treated here as a contextual perception, rather than a universally beneficial personality type. Improving motivational and emotional lives therefore involves identifying actual shortages, reducing avoidable burdens and supporting agency and connection. The research gives stronger grounds for specific, evaluated forms of support than for promises attached to an abundance label. For Alex, the practical aim is sustainable progress across important goals. Success should be judged by functioning and wellbeing, not by whether someone sounds sufficiently positive. == See also == {{ic|Use bullet points as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} ·      Scarcity (Wikipedia) ·      Self-determination theory (Wikipedia) ·      [[Motivation and emotion/Book/2025/Autonomy and intrinsic motivation in self-determination theory|Autonomy and intrinsic motivation in self-determination theory]] (Wikiversity) == References == {{Hanging indent|1= Adamkovič, M., & Martončik, M. (2017). A review of consequences of poverty on economic decision-making: A hypothesized model of a cognitive mechanism. ''Frontiers in Psychology, 8'', Article 1784. <nowiki>https://doi.org/10.3389/fpsyg.2017.01784</nowiki> Cannon, C., Goldsmith, K., & Roux, C. (2019). A self-regulatory model of resource scarcity. ''Journal of Consumer Psychology, 29''(1), 104–127. <nowiki>https://doi.org/10.1002/jcpy.1035</nowiki> Carvalho, L. S., Meier, S., & Wang, S. W. (2016). Poverty and economic decision-making: Evidence from changes in financial resources at payday. ''American Economic Review, 106''(2), 260–284. <nowiki>https://doi.org/10.1257/aer.20140481</nowiki> de Almeida, F., Scott, I. J., Soro, J. C., Fernandes, D., Amaral, A. R., Catarino, M. L., Arêde, A., & Ferreira, M. B. (2024). Financial scarcity and cognitive performance: A meta-analysis. ''Journal of Economic Psychology, 101'', Article 102702. <nowiki>https://doi.org/10.1016/j.joep.2024.102702</nowiki> de Bruijn, E.-J., & Antonides, G. (2022). Poverty and economic decision making: A review of scarcity theory. ''Theory and Decision, 92''(1), 5–37. <nowiki>https://doi.org/10.1007/s11238-021-09802-7</nowiki> Deci, E. L., & Ryan, R. M. (2000). The “what” and “why” of goal pursuits: Human needs and the self-determination of behavior. ''Psychological Inquiry, 11''(4), 227–268. <nowiki>https://doi.org/10.1207/S15327965PLI1104_01</nowiki> Fredrickson, B. L. (2001). The role of positive emotions in positive psychology: The broaden-and-build theory of positive emotions. ''American Psychologist, 56''(3), 218–226. <nowiki>https://doi.org/10.1037/0003-066X.56.3.218</nowiki> Griskevicius, V., Ackerman, J. M., Cantú, S. M., Delton, A. W., Robertson, T. E., Simpson, J. A., Emery Thompson, M., & Tybur, J. M. (2013). When the economy falters, do people spend or save? Responses to resource scarcity depend on childhood environments. ''Psychological Science, 24''(2), 197–205. <nowiki>https://doi.org/10.1177/0956797612451471</nowiki> Hamilton, R. W., Mittal, C., Shah, A., Thompson, D. V., & Griskevicius, V. (2019). How financial constraints influence consumer behavior: An integrative framework. ''Journal of Consumer Psychology, 29''(2), 285–305. <nowiki>https://doi.org/10.1002/jcpy.1074</nowiki> Haushofer, J., & Fehr, E. (2014). On the psychology of poverty. ''Science, 344''(6186), 862–867. <nowiki>https://doi.org/10.1126/science.1232491</nowiki> Haushofer, J., & Shapiro, J. (2016). The short-term impact of unconditional cash transfers to the poor: Experimental evidence from Kenya. ''The Quarterly Journal of Economics, 131''(4), 1973–2042. <nowiki>https://doi.org/10.1093/qje/qjw025</nowiki> Hobfoll, S. E. (1989). Conservation of resources: A new attempt at conceptualizing stress. ''American Psychologist, 44''(3), 513–524. <nowiki>https://doi.org/10.1037/0003-066X.44.3.513</nowiki> Huijsmans, I., Ma, I., Micheli, L., Civai, C., Stallen, M., & Sanfey, A. G. (2019). A scarcity mindset alters neural processing underlying consumer decision making. ''Proceedings of the National Academy of Sciences, 116''(24), 11699–11704. <nowiki>https://doi.org/10.1073/pnas.1818572116</nowiki> Laforet, B., Carrera, P., & Caballero, A. (2024). Breaking self-focused orientation in people who perceive economic scarcity: The influence of transcendent motivation to promote an abstract mindset and prosocial behavioral intentions. ''Scandinavian Journal of Psychology, 65''(4), 607–616. <nowiki>https://doi.org/10.1111/sjop.13009</nowiki> Mani, A., Mullainathan, S., Shafir, E., & Zhao, J. (2013). Poverty impedes cognitive function. ''Science, 341''(6149), 976–980. <nowiki>https://doi.org/10.1126/science.1238041</nowiki> Mittal, C., & Griskevicius, V. (2014). Sense of control under uncertainty depends on people's childhood environment: A life history theory approach. ''Journal of Personality and Social Psychology, 107''(4), 621–637. <nowiki>https://doi.org/10.1037/a0037398</nowiki> Ong, Q., Theseira, W., & Ng, I. Y. H. (2019). Reducing debt improves psychological functioning and changes decision-making in the poor. ''Proceedings of the National Academy of Sciences, 116''(15), 7244–7249. <nowiki>https://doi.org/10.1073/pnas.1810901116</nowiki> Roux, C., Goldsmith, K., & Bonezzi, A. (2015). On the psychology of scarcity: When reminders of resource scarcity promote selfish (and generous) behavior. ''Journal of Consumer Research, 42''(4), 615–631. <nowiki>https://doi.org/10.1093/jcr/ucv048</nowiki> Ryan, R. M., & Deci, E. L. (2000). Self-determination theory and the facilitation of intrinsic motivation, social development, and well-being. ''American Psychologist, 55''(1), 68–78. <nowiki>https://doi.org/10.1037/0003-066X.55.1.68</nowiki> Shah, A. K., Mullainathan, S., & Shafir, E. (2012). Some consequences of having too little. ''Science, 338''(6107), 682–685. <nowiki>https://doi.org/10.1126/science.1222426</nowiki> Shah, A. K., Shafir, E., & Mullainathan, S. (2015). Scarcity frames value. ''Psychological Science, 26''(4), 402–412. <nowiki>https://doi.org/10.1177/0956797614563958</nowiki> Szecsi, P., Kolumban, P., Taka, A., & Szaszi, B. (2025). The impact of financial resources on cognitive performance: A systematic review and meta-analysis. ''Collabra: Psychology, 11''(1), Article 147236. <nowiki>https://doi.org/10.1525/collabra.147236</nowiki> Szecsi, P., & Szaszi, B. (2024). Financial-scarcity-related cues’ impact on the cognitive performance of the poor: A meta-analysis. ''Collabra: Psychology, 10''(1), Article 122943. <nowiki>https://doi.org/10.1525/collabra.122943</nowiki> van Egmond, M. C., Navarrete Berges, A., Omarshah, T., & Benton, J. (2017). The role of intrinsic motivation and the satisfaction of basic psychological needs under conditions of severe resource scarcity. ''Psychological Science, 28''(6), 822–828. <nowiki>https://doi.org/10.1177/0956797617698138</nowiki> Whillans, A. V., Dunn, E. W., Smeets, P., Bekkers, R., & Norton, M. I. (2017). Buying time promotes happiness. ''Proceedings of the National Academy of Sciences, 114''(32), 8523–8527. <nowiki>https://doi.org/10.1073/pnas.1706541114</nowiki> Zhang, L., Xu, M., Du, X., Yang, Q., & Qiao, L. (2023). Scarcity mindset impairs distractor suppression but not target enhancement in selective attention: Evidence from ERPs. ''Neuropsychologia, 191'', Article 108739. <nowiki>https://doi.org/10.1016/j.neuropsychologia.2023.108739</nowiki> }} == External links == {{ic|Use bullet points as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} [https://The&#x20;psychology&#x20;of&#x20;scarcity&#x20;(American&#x20;Psychological&#x20;Association) ·      The psychology of scarcity (American Psychological Association)] [https://Overview&#x20;of&#x20;self-determination&#x20;theory&#x20;(Center&#x20;for&#x20;Self-Determination&#x20;Theory) ·      Overview of self-determination theory (Center for Self-Determination Theory)] [https://To&#x20;promote&#x20;happiness,&#x20;choose&#x20;time&#x20;over&#x20;money&#x20;(Whillans&#x20;and&#x20;Dunn,&#x20;Behavioral&#x20;Scientist ·      To promote happiness, choose time over money (Whillans and Dunn, Behavioral Scientist] [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Mindset/Scarcity]] 1nmg7n0udcpzzdgtfm7fvzcn9md3g25 2 331654 2844933 2840275 2026-11-09T06:05:08Z Jtneill 10242 /* Social contributions */ Use a numbered list 2844933 wikitext text/x-wiki == About me == Hello! I am a third-year student currently studying a Bachelor of Psychology/Bachelor of Law. I am most interested in clinical psychology, with a particular interests in criminal, child, family, and religion psychology. == My book chapter == The book chapter I am working on is [[Motivation and emotion/Book/2026/Romantic rejection and emotional response|romantic rejection and emotional response]]. It explores the ways in which romantic attachments develop, what happens when an attachment is lost, how this affects one's responses to romantic rejection, as well as, methods to support emotional regulation in light of rejection. == Social contributions == My social contributions include: {{ic|Use a numbered list as shown in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]}} * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FReinforcement_sensitivity_theory&diff=2829144&oldid=2828970 1:20, 29 August 26 - Put 'See also' resources in alphabetical order, and fixed doi links in references to be working clickable hyperlinks.] * [[Talk:Motivation and emotion/Book/2026/Empathy and jury decision-making#c-U3275873-20260828150100-Impacts of personal bias|1:01, 29 August 26 - Feedback on a book chapter - Empathy and jury decision-making]] * [https://uclearn.canberra.edu.au/courses/20143/discussion_topics/457904?entry_id=810833 1:11, 29 August 26 - Feedback provided on a topic development page on Motivation and Emotion Discussion page on UCLearn] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2025%2FPositive_criminology_and_motivation&diff=2838451&oldid=2790143 16:41, 11 October 26 - Made improvements to grammar throughout the page - Positive criminology and motivation] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2014%2FDeath_and_emotion&diff=2838496&oldid=2418856 17:03, 11 October 26 - Rewrote to improve clarity, and added initial scenario into a feature box - Death and emotion] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2019%2FEmotional_intelligence_and_anti-social_behaviour&diff=2838547&oldid=2552350 17:27, 11 October 26 - Rewrote sentences to improve clarity, improved grammar, and corrected in-text references - Emotional intelligence and anti-social behaviour] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FAutomaticity_and_goal_pursuit&diff=2840263&oldid=2840082 12:05, 15 October 26 - Formatted 'See also' section to be a bulleted list, and reordered into alphabetical order - Automaticity and goal pursuit] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FAutomaticity_and_goal_pursuit&diff=2840265&oldid=2840263 12:11, 15 October 26 - Italicised journal names in reference list in accordance with APA7 rules - Automaticity and goal pursuit] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FSensation-seeking_and_dopamine&diff=2840270&oldid=2839475 12:19, 15 October 26 - Formatted table captions, alphabetised 'See also' and 'External links' links - Sensation seeking and dopamine] * [https://uclearn.canberra.edu.au/courses/20143/discussion_topics/465466?entry_id=825457 12:25, 15 October 26 - Feedback provided on book chapter page on Motivation and Emotion Discussion page on UCLearn] * [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2025%2FPregnancy_loss_and_emotion&diff=2840274&oldid=2825415 12:40, 15 October 26 - Formatted reference list, made improvements to grammar - Pregnancy loss and emotion] d9nrswz027w0ynnivnn25ujhgk48oma 1 331831 2844925 2844285 2026-11-09T02:20:59Z Jtneill 10242 Book chapter feedback 2844925 wikitext text/x-wiki == Focus questions == This is looking fantastic, I am very interested in your topic and your focus questions are extremely interesting. Remember to use bullet points for the focus questions. [[User:U3284302|U3284302]] ([[User talk:U3284302|discuss]] • [[Special:Contributions/U3284302|contribs]]) 12:47, 4 September 2026 (UTC) <!-- Official topic development feedback --> {{METF/2026 |1= <!-- Title --> # Title and subtitle are correctly worded and use [[w:Letter case#Sentence casing|sentence casing]] |2= <!-- 1-level --> # Promising [[Motivation and emotion/Assessment/Major project/Structure|1-level heading structure]] – could benefit from further development (e.g., consider using subheadings) <!-- Alignment with focus questions --> # Very good alignment between sub-title, focus questions, and heading structure, but there may be room for improvement <!-- GenAI ---> # Are the headings based on [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, this needs to be acknowledged in the edit summaries, otherwise it violates academic integrity. |3= <!-- Overview--> # Good <!-- Scenario --> # Basic scenario # Consider using an example which is relatable to a wide, international audience, rather than a specific university student audience # Add an image to the scenario to help attract reader interest <!-- Description --> # A basic description of the problem/topic is planned or presented # What psychological theory/theories are most relevant? <!-- Focus questions --> <!-- Alignment and quality --> # Develop closer alignment between the sub-title, focus questions, and top-level headings # There are too many focus questions; only include questions that are needed to address the sub-title; avoid side-quests—these are usually better treated as examples or scenarios, or left out altogether so that the chapter can concentrate on the core task of synthesising the best psychological theory and research about the topic. <!-- Other --> # Use open- rather then close-ended focus questions |4= <!-- Key points--> <!-- Overall --> # Basic development # Provide more detailed edit summaries <!-- Theory and research --> # Strive for an integrated balance of the best psychological theory and research about this topic, with practical examples. <!-- GenAI ---> # Do these key points include [[Motivation and emotion/Assessment/Using generative AI|genAI content]]? If so, this needs to be acknowledged in the edit summaries, otherwise it violates academic integrity. <!-- Conclusion --> # Conclusion is underway # What are the practical, take-home messages? (address the focus questions) |5= <!-- Figure --> # Relevant figure(s) are presented and captioned # Add a relevant figure to the scenario <!-- Caption --> # Figure caption(s) provide(s) a somewhat clear description that is connected with the main text, but could be improved (e.g., proposed by who?) <!-- Cite --> # Cite each figure at least once in the main text using APA style (e.g., see Figure 1) <!-- Size --> # Consider increasing image size(s) (especially if they have text) to make them easier to view <!-- Creation --> # Well done on creating and uploading your own image! {{smile}}—this can also be listed on your user page as a social contribution |6= <!-- Learning feature --> <!-- Interwiki links ---> # Add in-text [[m:Help:Interwiki linking|interwiki links]] for first mention of key terms to [[w:|Wikipedia]] and/or [[Motivation and emotion/Book|book chapters]] (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- Scenarios/examples/case studies --> # Consider incorporating additional scenarios, examples, or case studies to illustrate key concepts. These could build on the Overview scenario or introduce new real-world situations in the main body of the chapter to demonstrate how the concepts apply in practice. <!-- Quiz --> # Consider including quiz question(s) about the take-home messages <!-- Tables --> # Promising use of [[Motivation and emotion/Wikiversity/Tables|table(s)]] # Include acknowledgement (e.g., citation(s)) for sources of information presented in the table <!-- References --> <!-- Overall --> # Good <!-- Systematic reviews --> # What are the most relevant systematic reviews/meta-analyses about this topic? <!-- APA style --> # Check and correct [https://apastyle.apa.org/instructional-aids/reference-guide.pdf APA referencing style]: ## make doi hyperlinks active (i.e., clickable) |8= <!-- Resources --> <!-- See also --> # See also ## Excellent ## To be developed (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- External links --> # External links ## Good ## Use [[w:Letter case#Sentence casing|sentence casing]] ## Use alphabetical order ## Include source in brackets after link |9= <!-- User page --> # Not developed – see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] <!-- Description about self --> |10= <!-- Social contribution --> # None summarised on user page with direct link(s) to evidence (see [[Motivation and emotion/Tutorials/Wiki editing#Social contributions|Tutorial 2]]). Looking ahead to the book chapter, see [[Motivation and emotion/Assessment/Chapter#Socialcontribution|social contributions]]. }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:53, 13 September 2026 (UTC) == Edits == Well done on the book chapter. You could add templates for the scenarios to highlight them. You could also add more pictures to make the page more interesting. [[User:Diaz Chas|Diaz Chas]] ([[User talk:Diaz Chas|discuss]] • [[Special:Contributions/Diaz Chas|contribs]]) [[User:Diaz Chas|Diaz Chas]] ([[User talk:Diaz Chas|discuss]] • [[Special:Contributions/Diaz Chas|contribs]]) 17:56, 3 November 2026 (UTC) <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is a basic chapter # The main area(s) for potential improvement: #* draw on mindset theory #* improve the quality of written expression #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution <!-- Overall - Edit summaries --> # Very brief editing history # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall – Citations --> # Basic use of academic, peer-reviewed citations to support claims <!-- Overall – Word count --> # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FScarcity_versus_abundance_mindset&diff=2844924&oldid=2840030 these copy edits] |2= <!-- Overview – Comments... --> # Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # The scenario does not sufficiently illustrate the topic # Use an example that a wider audience can relate to; less than 5% of the world population are university students <!-- Overview – Scenario - Figure --> # Instead of a diagram, use an image which illustrates the scenario taking a place; use the diagram in a subsequent section # Figure 1 and 2 were poorly/ambiguously named; I've requested that it be renamed on Wikimedia Commons <!-- Overview – Scenario - Feature box --> # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Briefly, problematic explanation of the psychological problem or phenomenon; doesn't explain mindsets <!-- Overview – Focus questions --> # The focus questions are reasonably good # The focus questions could be improved by: ## being [[w:Open-ended question|open-ended]] rather than [[w:Closed-ended question|closed-ended]] ## using bullet points as taught in [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] ## being presented in a feature box to help guide the reader (fixed) |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Good—key theories are quite well explained and applied # The chapter could be improved by focusing more on [[w:Mindset#Abundance_and_scarcity|mindset]] theory; more specifically, the chapter is overly focused on objective financial status rather than the perception of abundance/scarcity. The key point with abundance/scarcity mindset theory is that two people with the same resources can have different experiences based on having difference perceptions of abundance/scarcity, and that this has consequences for performance and well-being. <!-- Theory – Builds on --> # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Very good use of tables, figures, and/or lists to clearly convey key theoretical information <!-- Theory – Citations --> # In many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. <!-- Theory – Examples --> # Good use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Good to very good review of relevant research # Excellent emphasis on systematic reviews and/or meta-analyses # More detail about key studies would be ideal <!-- Research – Critical thinking --> # Reasonably good [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships |5= <!-- Integration comments... --> # Very good integration between the most relevant theory(ies) and the best research # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> <!-- Conclusion – Word count --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is reasonably good <!-- Style – Sentences --> ## Many sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections <!-- Style – Grammar --> # Grammar ## Use past tense when describing research studies, although implications of findings could be in the present tense <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) <!-- Style – Figures --> ## Figures ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style <!-- Style – Tables --> ## Table(s) ### Reasonably well captioned ### Use APA style for the caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style <!-- Style – Citations --> # In many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Style – References --> ## References use very good/ APA style: ### Hyperlink dois for 1-click access |8= # Basic use of learning features <!-- Learning features comments... --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Good use of figure(s) # Reasonably good use of table(s) # No use of feature boxes # Good use of scenarios, case studies, or examples <!-- Learning features – Quizzes --> # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~2 logged contributions without [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct (1-click) links to evidence]], so unable to easily verify and assess. See [[Motivation and emotion/Tutorials|tutorials]] for guidance about how to get direct links to evidence. # Thanks for the Wiki Commons upload; these could also be added as contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 02:20, 9 November 2026 (UTC) 0t5wiafeqrcybgadxyy6e405o2qou0w 1 331895 2844929 2842210 2026-11-09T03:27:15Z Jtneill 10242 Book chapter feedback 2844929 wikitext text/x-wiki <!-- Official topic development feedback --> {{METF/2026 |1= <!-- Title --> # Title and subtitle are correctly worded and use [[w:Letter case#Sentence casing|sentence casing]] |2= <!-- Headings --> <!-- Heading structure --> <!-- 1-level --> # Basic, [[Motivation and emotion/Assessment/Major project/Structure|1-level heading structure]] – could benefit from further development, perhaps using a 2-level structure (i.e., use subheadings) <!-- Alignment with focus questions --> # Excellent alignment between sub-title, focus questions, and heading structure |3= <!-- Overview--> # Very good <!-- Scenario --> # A scenario or case study is presented in a feature box with an image at the start of this section <!-- Description --> # A clear description of the problem/topic is planned or presented <!-- Style --> # Use 3rd person point of view for main body text (except 1st/2nd person point of view can work within feature boxes for scenarios) <!-- Focus questions --> # Focus questions are aligned with sub-title and top-level headings # Use [https://www.aresearchguide.com/write-in-third-person.html 3rd person perspective], although a case study or feature box could use 1st or 2nd person perspective |4= <!-- Key points--> <!-- Overall --> # Solid development # Consider introducing unconscious motivation # Highlight the most relevant theories and synthesise the best research on the topic; citations do not indicate that a sufficient literature search has been conducted # Provide more detailed edit summaries <!-- Scope --> # The scope is excellent (i.e., not too little/narrow or too big/broad) <!-- Citation style --> # Use [https://apastyle.apa.org/style-grammar-guidelines/citations/basic-principles APA style 7th edition for citations] <!-- Other --> # Use correct capitalisation ([https://apastyle.apa.org/style-grammar-guidelines/capitalization APA style is a "down" style]) – [https://polishedpaper.com/blog/capitalization-apa-style more info] # Consider using Studiosity Writing Feedback+ or a similar writing-support service (e.g., Grammarly) to improve the quality of written expression and check for grammatical and spelling errors in the book chapter draft. <!-- Conclusion --> # Conclusion is well underway # What are the practical, take-home messages? (address the focus questions) |5= <!-- Figure --> # Excellent - Relevant figure(s) presented, captioned, and cited <!-- Cite --> # Cite each figure at least once in the main text using APA style adjacent to figure display (e.g., see Figure 1) <!-- Learning feature --> <!-- Interwiki links ---> # One in-text [[m:Help:Interwiki linking|interwiki link]] for first mention of key term to [[w:|Wikipedia]]. Also embed links to [[Motivation and emotion/Book|book chapters]]. <!-- Scenarios/examples/case studies --> Consider incorporating additional scenarios, examples, or case studies to illustrate key concepts. These could build on the Overview scenario or introduce new real-world situations in the main body of the chapter to demonstrate how the concepts apply in practice. <!-- Quiz --> # Promising use of quiz question(s) # Place each quiz question in the most relevant section <!-- Tables --> # Also consider using tables to summarise key information |7= <!-- References --> <!-- Overall --> # Insufficient <!-- Systematic reviews --> # What are the most relevant systematic reviews/meta-analyses about this topic? <!-- APA style --> # Check and correct [https://apastyle.apa.org/instructional-aids/reference-guide.pdf APA referencing style]: ## capitalisation ## [[Help:Wikitext quick reference|italicisation]] ## use dois where available instead of other links |8= <!-- Resources --> <!-- See also --> # See also ## To be developed (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- External links --> # External links ## To be developed (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) ## Link to the most relevant external resources about this topic |9= <!-- User page --> # Used effectively <!-- Description about self --> # Description about self provided <!-- Links to profile(s) --> # Consider linking to your [https://portfolio.canberra.edu.au/ eportfolio] page and/or any other professional online profile or resume such as [https://www.linkedin.com/ LinkedIn]. This is not required, but it can be useful to interlink your professional networks. <!-- Link to book chapter --> # A link to the book chapter is provided |10= <!-- Social contribution --> # Good – two out of three types of contributions made with direct link(s) to evidence. The other type of contribution is making: #* direct improvements to other [[Motivation and emotion/Book|chapters (past or current)]] (valiant attempt - but, overall no changes were made; consider starting with more straightforward text-based changes) }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 01:22, 7 September 2026 (UTC) == Recommendation - Overview == Hello, Your topic looks to be going really well, I like how succinct it is and how all the headings seem to relate to one each other which is really good for reading flow. My biggest concern right now is the length of your overview, as if reads a little more like a storyline than it does an example of your goal pursuit topic. I think it'd be beneficial for you to keep some of the 'intrigue/action' so to speak of your overview, but really cut down the scenario into just the motivational component of your topic so potential readers don't get confused, sidetracked of overwhelmed. Great job [[User:Monuc9|Monuc9]] ([[User talk:Monuc9|discuss]] • [[Special:Contributions/Monuc9|contribs]]) 02:09, 9 October 2026 (UTC) == Resource recommendation == Your explanation of Type 1 and Type 2 processing was really clear. I found this article that might complement it; Evans & Stanovich (2013) review critiques of dual-process and dual-system theories and explain how Type 1 automatic responses and Type 2 deliberate reasoning fit into the broader dual-process framework. It connects directly to what you wrote and could be useful for anyone wanting to explore or critique dual-process theory further. St. B. T. Evans, J., & Stanovich, K. E. (2013). Dual-Process Theories of Higher Cognition: Advancing the Debate. Perspectives on Psychological Science, 8(3), 223–241. https://doi.org/10.1177/1745691612460685 [[User:StudentUC2026|StudentUC2026]] ([[User talk:StudentUC2026|discuss]] • [[Special:Contributions/StudentUC2026|contribs]]) 02:15, 23 October 2026 (UTC) <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is a good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem # The main area(s) for potential improvement: #* provide more detailed review of the best psychological research about the topic #* improve the quality of written expression #* integrate more strongly with other chapters by using embedded links to related topics <!-- Overall - Edit summaries --> # [[Motivation and emotion/Wikiversity/Edit summary|Edit summaries]] are used to communicate the changes for some edits, but would ideally be more descriptive and extensive <!-- Overall - GenAI --> # This chapter appears to be human-written # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] is appropriately acknowledged # GenAI use is acknowedged via a general statement (which has been moved to the talk page), but not by using edit summaries as required by the unit's [[Motivation and emotion/Assessment/Using generative AI|using genAI guidelines]] # There is likely unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]]; if so, this violates principles of academic integrity # In some places, there is overreliance on genAI # There may be unacknowledged use of [[Motivation and emotion/Assessment/Using generative AI|use of genAI]] # There is insufficient acknowledgement in [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]], with a shared link to the chatbot conversation(s), when adding [[Motivation and emotion/Assessment/Using generative AI|genAI output]]; this violates academic integrity principles # [[Motivation and emotion/Assessment/Using generative AI|GenAI use]] has not been appropriately acknowledged in [[Motivation and emotion/Wikiversity/Edit summary|Motivation and emotion/Wikiversity/Edit summary]] with links to the conversation sources despite previous feedback about this issue. Unacknowledged use of GenAI-generated content raises concerns about compliance with academic integrity principles and assessment requirements and [[Wikiversity:Artificial intelligence|Wikiversity's artificial intelligence policy]]. <!-- Overall – Citations --> # Good use of academic, peer-reviewed citations to support claims <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FAutomaticity_and_goal_pursuit&diff=2844928&oldid=2844240 these copy edits] |2= <!-- Overview – Comments... --> # Excellent <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Engaging scenario or case study <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # Use third person perspective <!-- Overview – Focus questions --> # The focus questions are reasonably good # Use third person perspective |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Very good—key theories are well explained and applied; minor areas for improvements <!-- Theory – Builds on --> # Builds on one [[w:|Wikipedia]] article and no related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Very good depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Insufficient/No use of tables, figures, and/or lists to convey key theoretical information <!-- Theory – Citations --> # Key citations are well used <!-- Theory – Examples --> # Very good use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Very good review of relevant research # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # More detail about key studies would be ideal <!-- Research – Critical thinking --> # Reasonably good [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Very good integration between the most relevant theory(ies) and the best research # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Good summary and conclusion <!-- Conclusion – Key points --> # Key points are well summarised # Key points are summarised in a basic way # Summarise key points <!-- Conclusion – Focus questions --> # Address the focus questions <!-- Conclusion – Take-home messages --> # Add practical, take-home message(s) |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is reasonably good <!-- Style – Sentences --> ## Some sentences could be explained more clearly (e.g., see {{vague}}, {{explain}}, {{rewrite}} etc. tags); consider using [https://www.studiosity.com/students/ Studiosity] for targetted feedback to help improve the quality of written expression <!-- Style – Language --> ## Use [https://www.grammarly.com/blog/first-second-and-third-person/ 3rd person perspective] (e.g., "it") instead of 1st (e.g., "we") or 2nd person (e.g., "you") in the main text. 1st or 2nd person can work well for case studies or feature boxes. <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## Avoid having sections with 1 sub-heading – use 0 or 2+ sub-headings (fixed) <!-- Style – Grammar --> # Grammar ## The grammar for many sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. ## [https://www.grammarly.com/blog/punctuation-capitalization/possessive-apostrophe/ Possessive apostrophes] are not used correctly (e.g., cats vs cat's vs cats') ## Use past tense when describing research studies, although implications of findings could be in the present tense <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] <!-- Style – Figures --> ## Figures ### Well captioned ### Brief captions; provide more detail to help connect the figure to the text ### Use this format for captions: '''Figure X'''. Descriptive caption goes here in sentence casing without bold or italics. [[Motivation and emotion/Assessment/Chapter/Figures|See example]]. ### Add captions <!-- Style – Figures - Citations --> ### Each Figure is referred to at least once within the main text using APA style <!-- Style – Citations --> # Citations use very good [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] ## Use ampersand (&) inside [[w:Bracket#Parentheses|parentheses]] and "and" outside parentheses ## Move embedded links to academic peer-reviewed sources into the [[{{PAGENAME}}#References|References]] as APA style citations with hyperlinked dois <!-- Style – References --> ## The References list is quite brief ## References use basic APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Include dois where available |8= <!-- Learning features comments... --> # Basic use of learning features <!-- Learning features – Wikipedia embedded links --> # Add more embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Insufficient use of figure(s) # No use of table(s) # Excellent/Very good/Good/Reasonably good/Basic use of feature box(es) # No use of feature boxes other than the opening scenario # Good use of scenarios, case studies, or examples <!-- Learning features – Quizzes --> # Basic use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # Basic use of the [[{{PAGENAME}}#External links|External links]] section ## Use the format shown in the [[Template:Motivation and emotion/Book chapter structure#External links|template]] |9= <!-- Social contribution comments... --> # ~6 logged, useful, mostly moderate contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add dir6ect links to contributions|direct links to evidence]] # Use a numbered list per [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]] }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 03:27, 9 November 2026 (UTC) tvdz186t74ndx9z657kequy7jll2w9f 1 332001 2844905 2844283 2026-11-08T23:06:04Z Jtneill 10242 Book chapter feedback 2844905 wikitext text/x-wiki == Heading casing == {| style="float: center; background:transparent;color:inherit;" |- | [[File:Crystal Clear app ktip.svg|48px|left]] | {{#if:Sarah Hagan06|Hi [[User:Sarah Hagan06|Sarah Hagan06]].|}} FYI, the recommended [[Wikiversity]] heading style uses [[w:Letter case#Sentence_case|sentence casing]]. For example:<br> <big><big>Self-determination theory</big></big> rather than <big><big>Self-Determination Theory</big></big> Here's an example chapter with correct heading casing: [[Motivation and emotion/Book/2019/Growth mindset development|Growth mindset development]] -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 23:01, 11 September 2026 (UTC) |} <!-- Official topic development feedback --> {{METF/2026 |1= <!-- Title --> # Title and/or subtitle not correctly worded and/or didn't use [[w:Letter case#Sentence casing|sentence casing]] (fixed) |2= <!-- Headings --> # See earlier comment about [[#heading casing|heading casing]] <!-- Heading structure --> <!-- 2-level --> # Promising [[Motivation and emotion/Assessment/Major project/Structure|2-level heading structure]] – could benefit from further development and/or refinement <!-- Alignment with focus questions --> # Insufficient alignment between sub-title, focus questions, and top-level headings |3= <!-- Overview--> # Good <!-- Scenario --> # A basic scenario or case study is presented in a feature box at the start of this section # I moved an image into the feature box to help attract reader interest # The image needs a caption to connect it to the scenario <!-- Description --> # A basic description of the problem/topic is planned or presented <!-- Focus questions --> # Develop closer alignment between the sub-title, focus questions, and top-level headings |4= <!-- Key points--> <!-- Overall --> # Solid development # Focus on providing an integrative review of the most relevant theories and research on the topic # Provide more detailed edit summaries <!-- Scope --> # The scope is excellent (i.e., not too little/narrow or too big/broad) <!-- Theory and research --> # Promising balance of theory and research <!-- Other --> # Use correct capitalisation ([https://apastyle.apa.org/style-grammar-guidelines/capitalization APA style is a "down" style]) – [https://polishedpaper.com/blog/capitalization-apa-style more info] <!-- Conclusion --> # Conclusion is well underway # What are the practical, take-home messages? (address the focus questions) |5= <!-- Figure --> # Relevant figure(s) are presented <!-- Caption --> # Figure caption(s) should include '''Figure X'''. ... followed by a descriptive caption that connects the figure to concepts being described in the main body text <!-- Cite --> # Cite each figure at least once in the main text using APA style (e.g., see Figure 1) |6= <!-- Learning feature --> <!-- Interwiki links ---> # Add in-text [[m:Help:Interwiki linking|interwiki links]] for first mention of key terms to [[w:|Wikipedia]] and/or [[Motivation and emotion/Book|book chapters]] (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) <!-- Scenarios/examples/case studies --> # Promising use of scenarios/examples/case studies <!-- Quiz --> # Promising use of quiz question(s) # Place each quiz question in the most relevant section # Focus the quiz question(s) on the take-home messages <!-- Tables --> # Promising use of [[Motivation and emotion/Wikiversity/Tables|table(s)]] # Include acknowledgement (e.g., citation(s)) for sources of information presented in the table # Add table caption # Cite each table at least once in the text using APA style |7= <!-- References --> <!-- Overall --> # Good # Surprisingly, Alderfer isn't cited <!-- Systematic reviews --> # What are the most relevant systematic reviews/meta-analyses about this topic? <!-- APA style --> # Check and correct [https://apastyle.apa.org/instructional-aids/reference-guide.pdf APA referencing style]: ## include hyperlinked dois ## page numbers should be separated by an en-dash (–) rather than a hyphen (-) |8= <!-- Resources --> <!-- See also --> # See also ## One of two link types provided ### Also link to relevant [[w:|Wikipedia]] pages <!-- External links --> # External links ## To be developed (see [[Motivation and emotion/Tutorials/Wiki editing|Tutorial 2]]) ## Link to the most relevant external resources about this topic |9= <!-- User page --> # Very basic <!-- Description about self --> # Very brief description about self – consider expanding <!-- Links to profile(s) --> # Consider linking to your [https://portfolio.canberra.edu.au/ eportfolio] page and/or any other professional online profile or resume such as [https://www.linkedin.com/ LinkedIn]. This is not required, but it can be useful to interlink your professional networks. <!-- Link to book chapter --> # A link to the book chapter is provided |10= <!-- Social contribution --> # None summarised on user page with direct link(s) to evidence (see [[Motivation and emotion/Tutorials/Wiki editing#Social contributions|Tutorial 2]]). Looking ahead to the book chapter, see [[Motivation and emotion/Assessment/Chapter#Socialcontribution|social contributions]]. }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 23:01, 11 September 2026 (UTC) == Potential Improvement == The book chapter is great so far. You could remove the assessment instructions from the external links and add more relevant links. You can also add more to the 'see also' section. [[User:Diaz Chas|Diaz Chas]] ([[User talk:Diaz Chas|discuss]] • [[Special:Contributions/Diaz Chas|contribs]]) [[User:Diaz Chas|Diaz Chas]] ([[User talk:Diaz Chas|discuss]] • [[Special:Contributions/Diaz Chas|contribs]]) 17:42, 3 November 2026 (UTC) <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is a basic chapter # The main area(s) for potential improvement: #* provide more detailed review of the best psychological research about the topic, especially Alderfer's original research #* integrate more strongly with other chapters by using embedded links to related topics #* more substantial engagement in social contribution <!-- Overall - Edit summaries --> # Insufficient use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to describe the changes made in each edit <!-- Overall - GenAI --> # This chapter appears to be human-written <!-- Overall – Citations --> # Basic use of academic, peer-reviewed citations to support claims # Only cite sources that you consult <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FERG_theory_and_motivation&diff=2844904&oldid=2839913 these copy edits] |2= <!-- Overview – Comments... --> # Underdeveloped <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Basic scenario or case study <!-- Overview – Scenario - Figure --> # Figure 1 is relevant to the scenario # The Figure 1 caption should explain more clearly how it is related to the scenario <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box # Put the scenario in a feature box (fixed) <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon # I suggest abbreviating this section and moving detail into subsequent sections <!-- Overview – Focus questions --> # Add focus questions in a feature box |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Reasonably good—relevant theories are selected, described, and applied, with some room for improvement <!-- Theory – Builds on --> # Doesn't build on [[w:|Wikipedia]] articles and related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Reasonably good depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Basic use of tables, figures, and/or lists to convey key theoretical information <!-- Theory – Citations --> # In many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. # If you didn't consult an original source (e.g., Alderfer, 1969), cite it as a [https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources secondary source] <!-- Theory – Examples --> # Basic use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Insufficient review of relevant research # More detail about key studies would be ideal # In many places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. ## I don't think Alderfer (1967), Alderfer (1969), Alderfer (1972), or other related articles such as Graham and Balloun (1973) were accessed in the preparation of this chapter <!-- Research – Critical thinking --> # Insufficient [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research ( |5= <!-- Integration comments... --> # Basic integration between the most relevant theory(ies) and the best research # The chapter places more emphasis on theory than on research; strive for an integrated balance # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Very good summary and conclusion # Highlight the importance of the problem or phenomenon of interest <!-- Conclusion – Key points --> # Key points are well summarised <!-- Conclusion – Focus questions --> # Address the focus questions <!-- Conclusion – Take-home messages --> # Add practical, take-home message(s) |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is good <!-- Style – Layout --> # Layout ## The chapter is reasonably well structured, with major sections using sub-sections ## The headings could be more clearly aligned with the focus questions ## See earlier comment about [[#Heading casing|heading casing]] <!-- Style – Grammar --> # Grammar ## Use past tense when describing research studies, although implications of findings could be in the present tense <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) ## Use [https://apastyle.apa.org/style-grammar-guidelines/capitalization/diseases-disorders-therapies sentence casing (not capitals) for disorders, therapies, theories, etc.] <!-- Style – Figures --> ## Figures ### Poorly captioned <!-- Style – Figures - Citations --> ### Refer to each Figure at least once within the main text (e.g., "(see Figure 1)") <!-- Style – Tables --> ## Table(s) ### Add APA style caption(s) ([[Motivation and emotion/Assessment/Chapter/Tables|see example]]) <!-- Style – Tables - Citations --> ### Refer to each Table at least once within the main text using APA style (e.g., see Table 1) <!-- Style – Citations --> # In many places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) ## If there are three or more authors, cite the first author followed by et al., then year. For example, either: ### in-text, Smith et al. (2020), or ### in [[w:Bracket#Parentheses|parentheses]] (Smith et al., 2020) <!-- Style – References --> ## References use reasonably good APA style: ### Check and correct use of italicisation ### Check and correct use of capitalisation[https://apastyle.apa.org/style-grammar-guidelines/capitalization] ### Include dois where available ### Hyperlink dois for 1-click access ### More copy editing is needed to fix formatting inconsistencies <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Basic use of learning features <!-- Learning features – Wikipedia embedded links --> # Add embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles. Adding interwiki links for the first mention of key words and technical concepts would make the text more interactive. See [[Motivation and emotion/Book/2020/Nutrition and anxiety|example]]. <!-- Learning features – Wikiversity embedded links --> # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Basic use of figure(s) # Consider including [[:File:Alderfer's ERG Theory.svg]] # Basic use of table(s) # EBasic use of feature box(es) # Basic use of scenarios, case studies, or examples <!-- Learning features – Quizzes --> # Basic use of quiz(zes) and/or reflection question(s) # The quiz questions could be more effective as learning prompts by being embedded as single questions within each corresponding section rather than as a set of questions at the end <!-- Learning features – See also --> # Insufficient use of the [[{{PAGENAME}}#See also|See also]] section ## Also include links to [[Motivation and emotion/Book|related book chapters]] ## Also include links to related Wikipedia articles <!-- Learning features – External links --> # Insufficient use of the [[{{PAGENAME}}#External links|External links]] section |9= <!-- Social contribution comments... --> # No logged contributions }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 23:06, 8 November 2026 (UTC) 4lxm78k5nwcty5wbdgots4i4rzessys 0 332187 2844946 2841237 2026-11-09T07:08:28Z Jtneill 10242 Copyediting 2844946 wikitext text/x-wiki {{title|Romantic rejection and emotional response<br>What emotional responses does romantic rejection evoke and how can they be regulated?}} __TOC__ == Overview == {{RoundBoxTop|theme=11}} '''Case study''' Maggie grew up with parents that {{g}} were loving and attentive, giving her everything she needed. Yet sometimes she found it difficult to form a deeper emotional connection with her parents or share her vulnerable feelings, as they would often keep conversations light or surface-level, and did not have personal conversations with their daughter. As a result, Maggie sometimes worried and questioned if they actually loved her, despite always having been provided for. '''What attachment style {{ic|Add link to a Wikiversity book chapter or Wikipedia article}} do you think Maggie is likely to be predisposed to?''' {{RoundBoxBottom}} [[wikipedia:Social_rejection#Romantic_rejection|Romantic rejection]] is a common yet extremely emotionally challenging experience that can lead to intense feelings of sadness, longing, loneliness, and difficulties in regulating [[Emotion|emotions]]. Understanding how and why people respond strongly to romantic rejection is important as attachment has consequences on psychological, physiological, and biological systems associated with security, reward, emotions and motivation. Using attachment theories, neuroscience, and emotional regulation techniques can help explain how romantic bonds develop, why their loss produces distress, the ways in which individual differences can affect responses, and which strategies may help regulate or support emotional responses. {{robelbox|theme=11|title=Focus questions}} <div style="{{Robelbox/pad}}"> * How do romantic attachments develop? * How does romantic rejection affect attachment and motivational systems? * What determines the nature and intensity of emotional responses to rejection? * How can rejection-related distress be reduced or managed? </div> {{Robelbox/close}} ==Romantic attachments== [[wikipedia:Romance|Romantic]] attachments are a fundamental part of human connection. They influence motivation, emotional wellbeing and behaviour. These attachments have developed over time through both evolutionary and biological bases, in attempts to increase survival and happiness {{f}}. Understanding these perspectives can help explain why romantic attachments form to begin with and why the loss of an attachment is so emotionally significant. === Attachment === [[wikipedia:Attachment_theory|Attachment theory]] outlines the main "attachment styles", otherwise known as ways in which people perceive and respond to [[wikipedia:Intimate_relationship#Intimacy|intimacy]] in relationships, and are parallel to those found in children throughout development stages (Levine & Heller, 2010). The theory designates three main styles: * Secure * Anxious * Avoidant People who are usually warm loving, and comfortable with intimacy tend to be ''secure.'' Whereas ''anxious'' people are often distracted with their relationships and crave intimacy, with constant worry about their partner's ability to love them back. Finally, people who tend to constantly try to minimize closeness and associate intimacy with a loss of their independence are considered ''avoidant'' (Levine & Heller, 2010). A person's attachment style can not only affect their view of intimacy, but also affect their: * way of dealing with conflict * attitude towards sex * ability to communicate wants and needs; or * expectations of a partner and the relationship (Levine & Heller, 2010). Levine and Heller (2010) claim all people fall, regardless of the stage at which their relationship is in, into one or a combination of these three categories, although a combination of anxious and avoidant is rare (Levine & Heller, 2010). This fourth, rare, category is termed the 'disorganised', of which only 5% of people fall into (Levine & Heller, 2010). ==== '''Origins of attachments - evolutionary safety''' ==== [[wikipedia:Attachment_in_adults#Styles|Adult attachment styles]] were initially hypothesised to be based primarily on a person's childhood and upbringing {{f}}. [[wikipedia:John_Bowlby|John Bowlby]] and [[wikipedia:Mary_Ainsworth|Mary Ainsworth]], building on their separate and joined research on [[wikipedia:Ethology|ethology]] and [[developmental psychology]], developed the initial theories on which attachment theory has evolved {{f}}. They proposed that infants possess a biological or evolutionary drive to form emotional attachments with others, primarily caregivers, as a mechanism for survival (Bretherton, 1992). From the ages of as young as six months to two years, children with consistent caregivers, who become their attachment figures, develop a mental representation or an "[[wikipedia:Internal_working_model_of_attachment|internal working model]]", influencing views of themselves, expectations, and methods of interacting and building relationships with others as they get older (Bergen, 2022). As the attachments develop throughout childhood, attachment figures can become a "secure base" they can return to for comfort, support, and safety, if caregivers were sensitive, responsible, and available, in which infants develop a "secure" attachment style (Bergen, 2022; Bowlby, 1988). Alternatively, avoidant or resistant attachment styles can develop if they were distant, unresponsive, and rigid; or an anxious attachment style if they were inconsistently responsive (Bergen, 2022; Levine & Heller, 2010). However, more recent developments have found that attachment styles in adulthood are more likely influenced by a variety of factors, including genetics, and life experiences, rather than being limited to the way in which parents cared for a person through infancy (Levine & Heller, 2010). Ultimately, attachment systems exist as a biological function of protecting a person from danger, especially during infancy, by ensuring their remain in close proximity to the care and support of others (their attachment figures), as a method of increasing the likelihood of survival and eventual reproduction (Mikulincer & Shaver, 2003). ==== '''Origins of attachment - biological basis''' ==== <blockquote>“Love is a biological necessity—it’s as needed for our well-being as exercise, water, and food, […] And from a neuroscientific viewpoint, we can really say that love blossoms in the brain.” (Cacioppo, as cited in Novotney, 2023, para.3).</blockquote> Aside from the evolutionary basis, romantic attraction is also based in neuroendocrinology. Early-stage romantic love, or being '[[wikipedia:Falling_in_love|lovestruck]]', is often attributed to a primitive part of the brain's reward system (Novotney, 2023). In these early stages a person normally experiences sympathetic nervous system reactions, such as sweaty palms or a pounding heart when they are with their loved one, and often feeling [[wikipedia:Separation_anxiety_disorder|separation anxiety]] when apart from them (Fisher et al., 2005). The lovers tend to express emotional dependence, heightened romantic passion, extreme empathy toward the beloved, sexual desires and possessiveness, the craving for emotional union, and obsessive thinking, reaching extremes where they change their habits to impress or remain in contact, or are even willing to die for the individual (Fisher et al., 2005). In cases where a lover experiences rejection, they often will protest the rejection and work to try to win the beloved individual back, expressing rage at the abandonment and despair (Fisher et al., 2005). Fisher et al. (2005) conducted a study on courtship attraction that used [[Functional Magnetic Resonance Imaging|functional magnetic resonance imaging]] (fMRI) to determine the neural mechanisms associated with romantic love, by studying 17 people {{where}} intensely "in love". The study found that a photograph of the beloved was an effective stimulus for eliciting feelings of intense romantic love, producing group activation in several regions of the brain, including the right [[wikipedia:Ventral_tegmental_area|ventral tegmental area]] (VTA) amidst [[wikipedia:Dopamine|dopamine]] cells (Aron et al., 2005; Fisher et al., 2005). The VTA is a main component of the brain's "reward system", as it is associated with focused attention, arousal, pleasure and the motivation to pursue and acquire rewards (Fisher et al., 2005). The VTA then activates various brain regions, including the caudate nucleus which contributes to reward detection and expectation (Fisher et al., 2005; Schultz, 2000). This suggests that romantic love may be a primary motivation system, or a fundamental human drive to mate, suggesting {{rewrite}} romantic love is the effects of a reward system as all drives are associated with the activation of dopamine (Fisher et al., 2005; Pfaff, 1999). Similarly, humans have been shown to respond to monetary rewards, demonstrating the neural activations of financial reinforcement overlap with regions that respond to human's primary reinforcers (Elliott et al., 2003). This can be applied twice {{huh}} as sex is a primary biological enforcer, and even abstract rewards can be used to effectively elicit neuronal responses (Elliott et al., 2003; Jozefowiez & Staddon, 2008). Ortigue et al. (2010) conducted further [[meta-analysis]] of published fMRI studies of love and their illustration of brain regions associated with the different forms of love. Ortigue et al. (2010) confirmed that all fMRI studies of love found the [[wikipedia:Cerebral_cortex#Connections|subcortical]] [[wikipedia:Dopaminergic_pathways|dopaminergic]] reward-related brain systems, which uses dopamine and [[wikipedia:Oxytocin|oxytocin]] receptors, responsible for motivating individuals to bond with another person. The review also further demonstrated that different types of love may involve different cerebral pathways which includes pathways associated with higher cognitive functions such as bodily [./Https://en.wikipedia.org/wiki/Self-image self-image] and [[social cognition]] (Ortigue et al., 2010). The study highlighted a total of 12 areas in the brain that work together to release dopamine, oxytocin, and [[wikipedia:Adrenaline|adrenaline]], indicating the [[wikipedia:Amygdala|amygdala]], [[wikipedia:Hippocampus|hippocampus]], and [[wikipedia:Prefrontal_cortex|prefrontal cortex]] (See Figure 1), which is very sensitive to pleasure-inducing behaviours, are all activated in the brain scans when talking about a loved one (Novotney, 2023; Ortigue et al., 2010). Romantic attachments ultimately develop through both evolutionary, physiological, and psychological methods. Attachment theory explains how and why emotional bonds are formed, to promote security and influence relationship patterns. Whilst reward systems highlight the neurophysiological component that strengthens romantic connections, suggesting romantic attachment fulfills the basic human needs for connection {{g}}. {{f}} {{RoundBoxTop|theme=11}} '''Case study cont.''' As Maggie grew older, in Year 11, she met Daniel and things seemed to change. Over their time finishing school and then later entering university Daniel became one of Maggie's closest friends, even entering the same university together after graduation. They were always together. Daniel made Maggie happy, was attentive, and slowly became someone Maggie could imagine building a future with. '' '''What type of attachment role do you think Daniel plays in Maggie's life?''' ''{{RoundBoxBottom}} == Effects of rejection == Romantic rejection can trigger physiological, psychological and neurological responses due to a disruption in a person's pre-determined romantic attachment. Romantic partners work as sources of emotional security and safety, so when a person is rejected, their established attachment bond and securities become threatened (Mikulincer & Shaver, 2003). Sometimes a rejection does not always deter the individual and can instead further motivate them to attempt to restore the lost connection, even if the relationship is no longer reciprocated (Mikulincer & Shaver, 2003). === '''Behavioural responses to a threatened attachment system''' === Functioning of an attachment system can be affected by the availability of one, or more, attachment figures in times of need, and their sensitivity and responsiveness to the individual's proximity-seeking behaviours (Mikulincer & Shaver, 2003). So, whilst nearly all children will become attached, including in situations where they experience parential abuse, not all attachments are secure attachments, as attachment theory poses that the quality of the interactions with attachment figures is the main reason for individual differences in the functioning of an attachment system (Mikulincer & Shaver, 2003) (see Figure 2). Applying the theory of attachment styles to experiences of romantic rejection, when an attachment figure (the beloved) is not physically or emotionally available to the lover in times of need or distress, is not sensitive or responsive to the lover's attempts at seeking proximity, the attachment system is disrupted (Mikulincer & Shaver, 2003). In that case, the feelings of distress, lack of proximity, or lack of safety are not alleviated. Instead, the initial distress felt is amalgamated by further doubts they can attain safety, trust, or the resources necessary for stress management (Mikulincer & Shaver, 2003). Once this occurs, attachment theorists have determined two methods of secondary attachment strategies of either ''hyperactivation'' or ''deactivation'' of the system; where hyperactivating individuals do not give up on their attachment attempts and instead intensify them to coerce the attachment figure's support and love (Mikulincer & Shaver, 2003). Alternatively, a deactivating individual gives up on their attachment attempts, attempting to deal with the dangers {{huh}} alone (Mikulincer & Shaver, 2003). This is a strategy to try and down-regulate their attachment system to avoid the distress and pain caused by the attachment figure's unavailability (Mikulincer & Shaver, 2003). {{RoundBoxTop|theme=11}} '''Case study cont.''' One day, Maggie had a panic attack while Daniel was at soccer practice, and as she was messaging and calling him to come help her, Daniel was not responding. This caused Maggie to become increasingly anxious, escalating her panic attack. Daniel's phone battery had gone flat at practice, so had not seen Maggie's calls or messages until a few hours after practice. '''How do you think this would affect Maggie and Daniel's relationship?''' {{RoundBoxBottom}} === '''Heartbreak and physical pain''' === Physical pain words are often used to describe experiences of social rejection or loss, such as a 'broken heart' or 'hurt feelings', which may be due to the similarities associated with [[Pain|physical]] and 'social pain' (Eisenberger, 2012; Tchalova & Eisenberger, 2015). Negative social evaluations, including rejection from a romantic partner, activates areas in the dorsal [[wikipedia:Anterior_cingulate_cortex|anterior cingulate cortex]] (dACC) and [[wikipedia:Insular_cortex|anterior insula]] (AI), which are brain regions associated with the distressful experiences of physical pain (Eisenberger, 2012). Understanding this overlap between physical and social pain provides further insights into both the intensity of emotional responses, and methods in which the pain can be alleviated. Overall, romantic rejection disrupts the security an attachment bond brings, whilst also still motivating an individual to pursue a person romantically. This helps further explain why an individual may experience emotional, and even physical, pain and still remain motivated to restore what was lost, whether literal or imagined. ==Nature and intensity of emotional responses to rejection== Romantic rejection can evoke a multitude of emotions in everyone. However, the intensity, duration, and expression of these emotions will differ amongst individuals. Attachment styles, rejection sensitivity, and individual differences would all play key parts in the expression of one's emotions. === '''Emotional responses''' === A wide variety of human emotions arise in response to rejection by other people, whether the rejection was real, anticipated, imagined, or merely remembered (Leary, 2015). Acceptance by other people developed [[wikipedia:Personality_psychology#Biopsychological_theories|biopsychological]] and emotional mechanisms for humans to recognise and cope with threats to acceptance and belonging (Leary, 2015). So, when an individual's sense of belonging or acceptance is threatened it can elicit emotions the following emotions in attempts to manage the rejection: * '''Hurt feelings''' - where the other person does not regard their relationship with the individual as valuable or important as they believe, leading them to feel rejected; * '''Jealousy''' - where the individual believes the other person values their relationship with them less than desired because of the presence of another third party; * '''Loneliness''' - where the individual believes the person who greatly values their relationship are not available for support or social interaction; * '''Guilt''' - where the individual believes they have done something that would lead the other to relationally devalue them, motivating them to repair the damage that their undesired behaviour has caused; * '''Shame''' - where the individual believes others' judgement as a person may lead to relation devaluation and possible rejection, leading to a desire to withdraw from social interactions because nothing can be immediately done to repair the damage to their image or value; * '''Social anxiety''' - feelings of nervousness in social interactions in anticipation to the possibility of conveying an undesired impression of themselves that will lower their value in another person's eyes; * '''Embarrassment''' - where the individual is concerned with how they are perceived by another when they think they have already conveyed an undesired impression of themselves to others; * '''Sadness''' - which arises from perceived loss, or when their affection for the other person is not returned or accepted; and * '''Anger''' - which arises when the individual perceives the other has unjustifiably behaved in a way that threatens their desire, wellbeing, or is considered an unjustifiable harm (Leary, 2015). However, people do not necessarily experience all of these emotions or to the same extent, as a person's individual differences affect their expression. {{RoundBoxTop|theme=11}} '''Case study cont.''' Maggie was really upset, as she needed Daniel in a time of need and she spiralled further, believing he was distancing himself, and got into a big argument with Daniel afterwards. Daniel suggested maybe they need some time apart to reevaluate themselves and their relationship. '''What effects do you think this will have on Maggie?''' {{RoundBoxBottom}} === '''Rejection sensitivity''' === Rejection sensitivity, the disposition to anxiously expect, readily perceive, and overwhelmingly respond to rejection (Shin et al., 2024). Rejection-sensitive individuals are more likely to anxiously expect rejection and therefore perceive others' ambiguous behaviours as an intentional rejection (Downey & Feldman, 1996). Similarly, those that enter romantic relationships with anxious expectations of rejection will recognise insensitive behaviours of the new partners as intentional rejection (Downey & Feldman, 1996). Consequently, individuals with a higher rejection sensitivity are more likely to interpret romantic rejection as a confirmation of their feelings of inadequacy, anxiety, anger or negative self-concept (Downey & Feldman, 1996; London et al., 2007). It also affects their quality of their relationships as rejection-sensitive men's jealousy and rejection-sensitive women's hostility results in feelings of diminished support and explain their partners' relationship dissatisfaction (Downey & Feldman, 1996). Rejection sensitivity can also be heightened by attachment styles as anxious or ambivalent attachment styles, that involve a fear of abandonment and need for validation, are more likely to exhibit rejection sensitivity (Shin et al., 2024). {{RoundBoxTop|theme=11}} '''Case study cont.''' As weeks passed, Maggie kept asking mutual friends about Daniel, checking his social media accounts, and trying to see him around university. Maggie became increasingly sensitive to even small rejections, interpreting friends saying they were too busy to hang out, or delayed responses to her messages as evidence that even her friends might abandon her. Her feelings of sadness and anxiety increased. '''How might this affect the nature and intensity of her emotions?''' {{RoundBoxBottom}} === '''Individual differences''' === Since physical and social pain are associated with the same neural circuitries individuals who are more sensitive to one kind of pain, whether physical or social, are therefore more sensitive to the other, meaning experiencing greater sensitivity to physical pain would likely result in greater social pain sensitivity (see Table 1), resulting in higher rejection sensitivity and/or a stronger anxious attachment style (Eisenberger, 2012). Higher rejection sensitivity, anxious attachment, or low self-esteem show greater dACC and/or AI activity when experiencing social pain (Tchalova & Eisenberger, 2015). Positive relationships throughout adolescence may also contribute to individuals being less sensitive to any negative social situations experienced later in their lives (Masten et al., 2012). '''Table 1''' ''The Relationship Between Social and Physical Pain'' {{center top}} {| class="wikitable" ! colspan="2" rowspan="2" | ! colspan="2" |Type of Pain |- |Social |Physical |- | rowspan="2" |'''Type of manipulation''' |Increase pain |↑ Physical pain |↑ Social pain |- |Decrease pain |↓ Physical pain |↓ Social pain |} {{center bottom}} Ultimately, romantic rejection can produce diverse emotional responses. Attachment styles, rejection sensitivity and individual differences may all affect the duration and intensity of an emotional reaction following rejection. ==Reducing or managing rejection-induced distress== Romantic rejection can trigger a variety of emotional responses, including separation distress, social pain, threats to attachment style, and behavioural responses in adjusting to the loss of an attachment. However, there are psychological strategies that may help individuals in regulating the responses and facilitate recovery. {{RoundBoxTop|theme=11}} '''Case study cont.''' Eventually, after speaking with a trusted friend, Maggie begins to recognise that her constant feelings of anxiety would only prolong the distress. Although her heartbreak had not disappeared, she decided to explore other healthier options of managing her emotions, and rediscovering herself outside of her relationship with Daniel. '''What techniques might Maggie use to overcome her anxiety and feelings of distress at missing Daniel?''' {{RoundBoxBottom}} === '''Adaptive emotional regulation''' === {{expand}} ==== '''Cognitive reappraisal''' ==== [[wikipedia:Cognitive_appraisal|Cognitive reappraisal]], an [[wikipedia:Adaptive_strategies|adaptive strategy]] of emotion regulation works by encouraging a person to change how a situation feels by reframing the way they interpret it (Wang & Yin, 2023; Zilverstand et al., 2017). Following romantic rejection, an individual may interpret their romantic loss as evidence of their personal inadequacy, however, reframing the rejection from a personal failure and instead to a result of incompatibility may be beneficial in reducing emotional distress and correct maladaptive thoughts (Wang & Yin, 2023). ==== '''Mindfulness''' ==== Mindfulness has also been proposed as an adaptive strategy for emotional regulation (Chambers et al., 2009). It involves paying deliberate attention to the present moment and remaining accepting and non-judgemental of the situation (Brockman et al., 2023). Whilst reappraisal works on changing one's thinking, mindfulness works on the person's relationship to their thinking (Brockman et al., 2023). Due to the overlap of physical and social pain, the factors that alter one type of pain are likely to have a similar effect on the other (Eisenberger, 2012). Using this principle, [[wikipedia:Paracetamol|paracetamol]] or [[wikipedia:Ibuprofen|ibuprofen]], which are known to reduce physical pains, may also reduce the social pain associated with rejection (Eisenberger, 2012). === '''Emotion suppression''' === Alternatively, [[wikipedia:Expressive_suppression|expressive suppression]], a maladaptive behavioural strategy that works towards inhibiting the behaviours associated with emotional responses, such as facial expressions, gestures, and verbal phrases (Goldin et al., 2008) {{g}}. === '''Limitations of emotional regulation techniques''' === Reappraisal is likely more beneficial {{ic|than?}} in reducing immediate neural activity and decreasing negative emotional experiences, however, suppression produced later neural emotional responses, decreased emotional behaviours, experiences and facial expressions, yet increased neural responses (Goldin et al., 2008) {{rewrite}}. However, whilst cognitive reappraisal is an effective technique in clinical practice, it may not always translate to the individual's life due to a lack of practice, and is likely more effective and replicable across experiences closely linked to the individual's real-life experiences (Wang & Yin, 2023). Despite this, the efficacy of each strategy would depend on the individual, context, environment, age, purpose of the strategy, and other individual differences (Brockman et al., 2023). === '''Social support''' === Social support is a widely known method used to mitigate both emotional and social distress, and is associated with reduced activity in the dACC and AI where increased activity is associated with pain processing (Eisenberger, 2012; Tchalova & Eisenberger, 2015). Therefore, spending time with friends and in an individual's daily support network indicates reduced activity in the dACC and AI, allowing the individual to reduce both the social and physical pains associated with romantic rejection (Masten et al., 2012; Tchalova & Eisenberger, 2015). Effective emotional regulation following romantic rejection likely requires a combination of strategies to address immediate distress, regulate attachment, and elicit long-term adjustments. Whilst these strategies are useful in providing support and assisting with recovery, it may just be that emotional responses to rejection are inevitable. Although there are several approaches to manage rejection, the research on overall and immediate recovery remains limited. Strategies should instead be adapted to a person's individual emotional needs rather than using a 'universal' treatment. {{RoundBoxTop|theme=11}} '''Case study cont.''' After seeing a psychologist, who recommended Maggie surround herself with her friends to build her confidence and individual interest again, encouraging she stay fit and pick up a new sport, and showing her techniques of mindfulness, Maggie was able to work through her heartbreak. She also begun using cognitive reappraisal techniques to reframe the small rejections that were increasing her anxiety, and began relying on her own regulation techniques to overcome challenges. After some time had passed and Maggie was feeling confident in herself, she reached out to Daniel to try to rekindle their relationship, now that she was feeling secure and was not dependent on another person for her own safety and happiness. {{RoundBoxBottom}} ==Conclusion== Romantic rejection can greatly influence emotions and motivated behaviour due to the complexity and interconnectedness of psychological and biological systems. Romantic attachments can provide security, a sense of belonging, and mimic rewards, explaining why the disruption of an attachment can trigger intense distress and emotional effects. However, the duration and intensity of such effects may vary according to individual differences, particularly in attachment style and sensitivity to rejection. Notably, the emotional responses can be managed through cognitive appraisal, mindfulness, suppression and social support, reducing distress, and supporting emotional recovery. Overall, romantic rejection evokes interconnected emotional and motivational responses, but emotional regulation is possible through evidence-informed strategies. Understanding the underlying psychological mechanisms can therefore provide valuable insights into managing romantic rejection, emotional distress and promoting practical approaches to psychological wellbeing. ==See also== * [[Motivation and emotion/Book/2016/Attachment type and emotion|Attachment type and emotion]] (Book chapter, 2016) * [[Motivation and emotion/Book/2014/Belongingness motivation#Positive Outcomes of Successful Belongingness and How to Cope with Rejection|Belongingness motivation]] (Book chapter, 2014) * [[Emotional regulation]] (Wikiversity) * [[wikipedia:History_of_attachment_theory|History of attachment theory]] (Wikipedia) * [[Motivation and emotion/Book/2025/Rejection sensitivity|Rejection sensitivity]] (Book chapter, 2025) * [[Motivation and emotion/Book/2021/Sorry#Social rejection|Social rejection]] (Book chapter, 2021) * [[wikipedia:Theories_of_love|Theories of love]] (Wikipedia) ==References== {{Hanging indent|1= Aron, A., Fisher, H., Mashek, D. J., Strong, G., Li, H., & Brown, L. L. (2005). Reward, motivation, and emotion systems associated with early-stage intense romantic love. ''Journal of Neurophysiology'', ''94''(1), 327–337. https://doi.org/10.1152/jn.00838.2004 Bergen, D. (2022). Developing attachment. In ''Theories of Early Childhood Education'' (pp. 118–127). Routledge. Bowlby, J. (1988). ''A secure base: Clinical applications of attachment theory''. Routledge. Bretherton, I. (1992). The origins of attachment theory: John Bowlby and Mary Ainsworth. ''Developmental Psychology'', ''28''(5), 759–775. https://doi.org/10.1037/0012-1649.28.5.759 Brockman, R., Ciarrochi, J., Parker, P., & Kashdan, T. B. (2023). Behaving versus thinking positively: When the benefits of cognitive reappraisal are contingent on satisfying basic psychological needs. ''Journal of Contextual Behavioral Science'', ''27'', 120–125. https://doi.org/10.1016/j.jcbs.2023.01.005 Chambers, R., Gullone, E., & Allen, N. B. (2009). Mindful emotion regulation: An integrative review. ''Clinical Psychology Review'', ''29''(6), 560–572. https://doi.org/10.1016/j.cpr.2009.06.005 Downey, G., & Feldman, S. I. (1996). Implications of rejection sensitivity for intimate relationships. ''Journal of Personality and Social Psychology'', ''70''(6), 1327–1343. https://doi.org/10.1037/0022-3514.70.6.1327 Eisenberger, N. I. (2012). The pain of social disconnection: Examining the shared neural underpinnings of physical and social pain. ''Nature Reviews Neuroscience'', ''13'', 421–434. https://doi.org/10.1038/nrn3231 Elliott, R., Newman, J. L., Longe, O. A., & Deakin, J. F. W. (2003). Differential response patterns in the striatum and orbitofrontal cortex to financial reward in humans: A parametric functional magnetic resonance imaging study. ''The Journal of Neuroscience'', ''23''(1), 303–307. https://doi.org/10.1523/jneurosci.23-01-00303.2003 Fisher, H., Aron, A., & Brown, L. L. (2005). Romantic love: An fMRI study of a neural mechanism for mate choice. ''Journal of Comparative Neurology'', ''493''(1), 58–62. https://doi.org/10.1002/cne.20772 Goldin, P. R., McRae, K., Ramel, W., & Gross, J. J. (2008). The neural bases of emotion regulation: Reappraisal and suppression of negative emotion. ''Biological Psychiatry'', ''63''(6), 577–586. https://doi.org/10.1016/j.biopsych.2007.05.031 Jozefowiez, J., & Staddon, J. E. R. (2008). 1.06 - Operant behaviour. In ''Learning and Memory: A Comprehensive Reference'' (pp. 75–101). Academic Press. Leary, M. R. (2015). Emotional responses to interpersonal rejection. ''Dialogues in Clinical Neuroscience'', ''17''(4). https://doi.org/10.31887/DCNS.2015.17.4/mleary Levine, A., & Heller, R. (2010). ''Attached''. Tarcher. London, B., Downey, G., Bonica, C., & Paltin, I. (2007). Social causes and consequences of rejection sensitivity. ''Journal of Research on Adolescence'', ''17''(3), 481–506. https://doi.org/10.1111/j.1532-7795.2007.00531.x Masten, C. L., Telzer, E. H., Fuligni, A. J., Lieberman, M. D., & Eisenberger, N. I. (2012). Time spent with friends in adolescence relates to less neural sensitivity to later peer rejection. ''Social Cognitive and Affective Neuroscience'', ''7''(1), 106–114. https://doi.org/10.1093/scan/nsq098 Mikulincer, M., & Shaver, P. R. (2003). The attachment behavioural system in adulthood: Activation, psychodynamics, and interpersonal processes. In ''Advances in Experimental Social Psychology'' (pp. 53–152). Elsevier Science. Novotney, A. (2023). What happens in your brain when you’re in love? ''American Psychological Association.'' https://www.apa.org/topics/marriage-relationships/brain-on-love Ortigue, S., Bianchi-Demicheli, F., Patel, N., Frum, C., & Lewis, J. W. (2010). Neuroimaging of love: fMRI meta-analysis evidence toward new perspectives in sexual medicine. ''The Journal of Sexual Medicine'', ''7''(11), 3541–3552. https://doi.org/10.1111/j.1743-6109.2010.01999.x Pfaff, D. (1999). ''Drive: Neurobiological and molecular mechanisms of sexual motivation.'' MIT Press. Schultz, W. (2000). Multiple reward signals in the brain. ''Nature Reviews Neuroscience'', ''1''(3), 199–207. Shin, J., Han, K. S., & Shin, H. J. (2024). Rejection sensitivity: A concept analysis. ''Journal of Korean Academy of Psychiatric and Mental Health Nursing'', ''33''(3), 253–261. https://doi.org/10.12934/jkpmhn.2024.33.3.253 Tchalova, K., & Eisenberger, N. I. (2015). How the brain feels the hurt of heartbreak: Examining the neurobiological overlap between social and physical pain. In A. W. Toga (Ed.), ''Brain Mapping: An Encyclopedic Reference'' (pp. 15–20). Academic Press: Elsevier. Wang, Y.-X., & Yin, B. (2023). A new understanding of the cognitive reappraisal technique: An extension based on the schema theory. ''Frontiers in Behavioral Neuroscience'', ''17''. https://doi.org/10.3389/fnbeh.2023.1174585 Zilverstand, A., Parvaz, M. A., & Goldstein, R. Z. (2017). Neuroimaging cognitive reappraisal in clinical populations to define neural targets for enhancing emotion regulation. a systematic review. ''NeuroImage'', ''151'', 105–116. https://doi.org/10.1016/j.neuroimage.2016.06.009 }} ==External links== * [https://www.columbiapsychiatry.org/news/how-attachment-styles-influence-romantic-relationships How attachment styles influence romantic relationships] (Columbia Psychiatry) * [https://hms.harvard.edu/news-events/publications-archive/brain/love-brain Love and the brain] (Harvard Medical School) * [https://youtu.be/gMRph_BvHB4?si=7A6iFYMgC7VdC2Vv The science of love, desire and attachment] (YouTube) [[Category:{{#titleparts:{{PAGENAME}}|3}}]] [[Category:Motivation and emotion/Book/Relationships]] o9vhg2miqvh9vf5b9qtcbaph24ehi2g 0 332412 2844919 2844839 2026-11-09T01:13:33Z Scogdill 1331941 2844919 wikitext text/x-wiki =Event= International championship boxing match between British Jem Smith and Australian Frank Slavin on 23 December 1889 in Bruges, Belgium. ==Overview== On 23 December 1889 a championship boxing match in Bruges, Belgium, ended with cheating on the British side: British Jim Smith was losing, so his supporters entered the ring, took advantage of Smith's holding Australian Frank Slavin or getting him near the ropes and beat him up, using fists, sticks, "knuckle-dusters," "life preservers" and boots. The referee ruled the match a draw to prevent Slavin from being killed and then fled. The ''Cork Constitution'' called it "the Smith-Slavin piece of brutality."<ref>"Mr. Abington." ''Cork Constitution'' 14 January 1890, Tuesday: 7 [of 8], Col. 5b [of 6]. ''British Newspaper Archive''https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001648%2F18900114&page=7&article=099&stringtohighlight=mandeville+viscount. Same title and p.</ref> A knuckle-duster was "A metal instrument made to cover the knuckles,"<ref>“Knuckle-duster, ''N.''”  ''Oxford English Dictionary'', Oxford UP,  December 2024, https://doi.org/10.1093/OED/6130372797.</ref> like brass knuckles, and a life preserver was "A stick or truncheon weighted at one end" with lead.<ref>“Life-preserver, ''N.''”  ''Oxford English Dictionary'', Oxford UP,  September 2026, https://doi.org/10.1093/OED/1055046410.</ref> One meeting of the boxing-oriented London Pelican Club was held almost immediately. Then a series of meetings following an investigation occurred in the first week of January (the [[Social Victorians/Boxing/Pelican Club Meeting Smith-Slavin match|Pelican Club meetings]] referred to below). Slavin followed this fight with a challenge for American John L. Sullivan, saying he would fight in America or Australia, but not in a private venue in England. Many, many newspapers covered this fight and the reaction to it in the boxing community. Copy-and-paste journalism and the lack of copyright laws means that many of the stories are all or in part identical to others, so no attempt has been made here to offer complete coverage. Specialized sports coverage is privileged. ==Logistics== * 23 December 1889, Monday, 8:00–9:00 a.m., actual fighting commencing at 8:35 * "the private grounds of a gentleman's residence near Bruges, Belgium"<ref name=":1">"The Great Fight. Smith & Slavin for £1000. Disorderly Proceedings. Brutal Attack on Slavin. Smith Knocked Down Repeatedly. He Leaves the Ring. A Draw Declared after 14 Rounds." ''The Sportsman'' 24 December 1889, Tuesday: 3 [of 4], Col. 1a – 4, Col. 6c [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001055%2F18891224&page=3&article=057&stringtohighlight=mandeville+viscount. Same print title and p.</ref> (3, Col. 1a) * Stakes: £1,000 ==Related Events== * [[Social Victorians/Boxing/Pelican Club Meeting Smith-Slavin match|Pelican Club Meetings about the Smith-Slavin match]] * the "[[Social Victorians/Boxing/Fracas at the Trocadero|Fracas at the Trocadero]]" ==Who Was Present== # Jem Smith, British boxer ## Jack Harper, Smith's second ## Jack Baldock, Smith's second ## Mr J. Fleming, umpired for Smith # Frank Slavin, Australian boxer ## Josh Cosnett, Slavin's second ## Bob Kirby, Slavin's second ## Mick Taylor, "superintended the arrangements in his [Slavin's] corner" ## Mr W. Riley umpired for Slavin # "the company round the ring ## Lord Mandeville — [[Social Victorians/People/Mandeville|Kim Montagu, Viscount Mandeville]] ## Lord Royston ## Hon. M. Sandys ## Mr Abington — Mr. G. Abington Baird, Smith's manager? and horseman (see description in Anthology) ## Mr F. Kotchie ## Mr J. Kilby — Jack Kilby, "a real sportsman"<ref name=":1" /> (3, Col. 1c) ## Mr C. Parsons ## Mr Ike White ## Mr C. Morton ## Mr Harris ## Mr E. Bayley — Teddy Bayley ## Mr John Lewis (Australia) — Jack Lewis, Slavin's manager ## Mr J. Vesey — Joe Vesey, more often, or Vezey, referee ## Mr F. Hinde — Frank Hinde ## Mr M. Taylor ## Mr J. Calder — timekeeper ## "Pop" Joy ## R. Habbijam — Bob Habbijam ## G. ("Barney") Sheppard — "superintended the pitching of the ring"<ref name=":1" /> (3, Col. 3b) ## Jem Carney ## Tom Smith ## Mangie [?] Hyams ## Matthews ## Summers ## Boulton ## Mr G. T. Dunning — Tom Dunning, worked at ''The Sportsman'' and served as treasurer for the subscription to collect a cash prize for Slavin. ## "several others, including two or three reporters" — "three scribes with pockets bulging from a surplusage of note-books dropped in"<ref name=":1" /> (3, Col. 1c) ## The writer of the big 24 December article, who reports for ''The Sportsman'' and who is not the "well-known sporting journalist"<ref name=":1" /> (3, Col. 1b) who had heard that Slavin had been arrested in Margate # "an English resident in Bruges"<ref name=":1" /> (3, Col. 3a) # "Pop" Hinde # C. Horton # "a mob of Birmingham men"<ref name=":1" /> (3, Col. 2c) # Lord Rosslyn ? # "The Squire" # ==Entertainment== ==Anthology== === The Sportsman === The Tuesday, 24 December 1889 issue of ''The Sportsman'' devoted page 3 and most of page 4 (nearly 13 full columns) entirely to this story. This reporter's writing style is very ornate: * "Long before the earliest purveyor of the lacteal fluid arrived in the quiet suburban street to wake the sleepers with his hideous yelping" (3, Col. 1c) * "For a time it [the sea] was a bit rough, and one of the good sailors commenced quoting Byron. 'O'er the glad waters of the dark blue sea,' sang he. Well, it was not too cerulean, but there was no question as to its gladness. The English Channel is generally built that way, and it was evidently making extra merry on account of the season."<ref name=":1" /> (3, Col. 2a) * "Water was at a premium, while soap could only be obtained by borrowing from the one or two lucky ones who had thought to bring that useful saponaceous compound with them."<ref name=":1" /> (3, Col. 2b) * "While awaiting the refection Slavin opened the piano which stood at one end of the ''salle-à-manger'', and dashing his lingers over the keys soon gave evidence that he was no mean performer on that instrument."<ref name=":1" /> (3, Col. 2c) * "He looked wonderfully well, having worked off much superfluous adiposity during the last few weeks' training."<ref name=":1" /> (3, Col. 2c) Besides the street-fighting terms (knuckle-dusters, life preservers) above, he also uses slang and local vocabulary like sabots (wooden clogs worn by working-class Belgians), Brums (people from Birmingham [?]) This is, then, a very long article, reproduced here in full except where the text is illegible, the very large block quote broken up by level-2 heads for navigation:<blockquote>The long-talked-of fight between Jem Smith, Champion of England, and Frank P. Slavin, Champion of Australia, took place between eight and nine o'clock yesterday morning in the private grounds of a gentleman's residence near Bruges, Belgium. The contest, as everybody knows, was for 1000''l''. Thanks to the most cowardly and disgraceful behaviour of a gang of ruffians in Smith's corner, the referee was forced to declare the fight a draw at the close of the fourteenth round. Full details are given below.</blockquote> ==== THE JOURNEY TO THE CONTINENT. ==== <blockquote>(By our special reporter.) [?] travellers accustomed to make long and frequent journeys do not trouble themselves much about starting. The pangs of parting are easly effaced, and after a few years of "globe-trotting," as the Yankees are pleased to call it, beyond looking after personal comforts the travelling Briton has very little trouble. I have made many notable journeys upon all sorts of errands, but must confess that entering upon my last jaunt brought not a few qualms — other than those likely to be experienced at sea. The preliminaries of the international fight, which was the reason of the trip from town, had not been carried through without many untoward circumstances arising to spoil the fun. On Saturday, however, there was every prospect of the business being brought to a successful termination, and when word was brought me that on the following morning our party were to leave London at an early hour there was no need for further hesitation, and preparations for the journey were rapidly made. What a day it was! Rain of a most annoying and penetrating kind fell until well into the night, making every one hurry to bring their day's business, or pleasure, to an end, that they might get indoors out of the dismal, depressing weather. Just as I had thought all safe for the [night came] A Rude Shock. [Arriving??] at the office of T<small>HE</small> S<small>PORTSMAN</small> I found a well-known sporting journalist, whose expressive features at once conveyed to my practised eye that "something had happened." His right hand convulsively clutched a telegram, and it was quickly patent that this innocent-looking piece of paper was the cause of the trouble. "What do you think of this?" asked he, handing over the document. Only a few words were pencilled thereon, but these were enough to cause us alarm. "Stoppage, but think can get bail. — Slavin." Here was a pretty "go," the mystic words being translated meaning that the Australian had been "pinched" at Margate. Before we had thoroughly grasped the situation a second wire arrived containing the definite information that Slavin had been arrested at the Kentish watering-place and that he had a difficulty in finding bail among strangers. This dire news sent our spirits down to zero. Two acts of the little drama we were enacting had been very depressing, but the third brought sunshine again. Close upon the heels of the second telegram came a third, and it was with trembling fingers that at the request of my friend I opened the missive. A glance was enough — Slavin was free, and on his way to Dover. This sent us home satisfied that all would be well on the morrow now that both the principal actors in the contest were on the spot or nearby. Daylight brought with it A May Morning. Long before '''the earliest purveyor of the lacteal fluid''' arrived in the quiet suburban street to wake the sleepers with his hideous yelping, a cross between that of a beaten dog and a Comanche Indian, I had turned out, as there was no time to be lost. It was a delightful morning, the rain clouds having vanished, and being replaced by brilliant sunshine the weather being more akin to early summer than that usually associated with late December. The early promise did not last, as before eight o'clock the south-westerly breeze brought up rain clouds once more, and a fine free sample of "London peculiar" had taken possession of the streets as I wended my way towards Cannon-street Station. Ten o'clock was the hour named, but half an hour before that time several of the party had arrived at the trysting place. First to be noticed was Bob Habbijam, in company with two less-known sports, and this trio had not the dim terminus long to themselves. Jack Lewis, looking "all broke up," put in an appearance a few minutes later, while at the same time three scribes with pockets bulging from a '''surplusage of note-books''' dropped in. It was very soon evident that the company would be much larger than intended, as cabs rattled up continually, bringing a further complement. Tom Smith, Bob Kirby, Barney Sheppard, "Pop," and Frank Hinde were the next to join us, and in quick succession came Teddy Bayley, Will Riley, and Joe Vezey [sic], who was to occupy the unthankful office of referee. According to the original conditions, a number of the intending spectators should have proceeded by way of Calais overnight, but by some means or other they managed to miss the train, and it was owing to this fact that so many were present on Sunday morning. There was no disguising the fact that such a crowd would draw attention, and militate against the secrecy necessary to insure us against intervention. There was no help for it, however, and before the Continental express came in from Charing-Cross "The Squire," Ike White, J. Kilby, C. Horton, C. Parsons, and J. Fleming had swelled the ranks of the ''voyageurs''. Down to Dover. It was only by judicious squeezing and packing that room could be found for all in the train, already well freighted with passengers, but eventually everyone managed to find a corner, luggage being conspicuous by its absence. I had a real sportsman for companion, Jack Kilby, of the Ferry Hotel, Cookham. Having missed the train overnight, not to be thwarted of his promised journey he arranged to proceed to town by road in the early morning. Instructing two lads to sit up through the night so as to be awakened in good time, Kilby turned in. At four o'clock he had the horse put in the shafts of a dog-cart, and drove slick away to Cannon-street. It was a particularly quiet trip, broken only by stoppages at Ashford and Folkestone, where some of the irrepressibles saw fit to leave the train and perambulate the platform. This, to say the least of it, was a foolish proceeding, as it fairly "gave the game away," and there was almost an air of expectancy about the officials when, after a run of nearly two hours, the South-Eastern express pulled up on Dover [Col. 1c–2a] Pier. Thoughts of coming trouble had ere this sobered down the playful ones, and it did not add to their joy when, looking seawards, they saw what is known as "dirty" weather in store. On the Briny. The transfer of passengers from the pier to the deck of the Princess Henriette was rapidly effected, and "once on board the lugger" my fellow-travellers disappeared as if by magic, but as rapidly came to light again, having, in view of developments likely to appear later, made arrangements below. There was a general changing of headgear, the bowler being discarded for the more useful tight-fitting cap — and what a variety were donned! As on the appearance of the clown in the pantomime, now the fun commenced. Before noon, when the hawsers were cast off, several shining lights in the boxing world prepared for the worst, the long rollers which broke in against the pier giving them the greatest alarm. Many had never previously ventured upon anything of a more stormy character than the Thames, and but for the fear of reproach would have turned back. As the "Princess" swung off from the pier the two "Bobs," Kirby and Habbijam, betook themselves to the "rail" in expectation of an attack of ''mal de mer''. What a pitiable sight they presented, but in a few minutes they found many brothers in misfortune, Tom Smith caving in. For a time it was a bit rough, and one of the good sailors commenced quoting Byron. "O'er the glad waters of the dark blue sea," sang he. Well, it was not too cerulean, but there was no question as to its gladness. The English Channel is generally built that way, and it was evidently making extra merry on account of the season. Once away from the shore-swell it was smooth enough, and the sickly division came round wonderfully. Frank Hinde, who played his old part of low comedian, amused them, and at length by his wonderful flow of spirits — animal and otherwise — had the worst cases on their legs again. A few exceptions there were, half a dozen or so of the swells having "sought the seclusion which the cabin grants," and there they stayed. Our low-comedy merchant now found a a [sic] serious rival in "Pop," and between them they kept the coterie on the quarter-deck from being dull. Yarns were spun by this pair of drolls, and the merry jest went round until more substantial fare was in request at the table. Both the aforementioned did their share, the way Hinde put away the humble yet satisfying cold meat and pickles causing intense envy in the breasts of the less hardy mariners. A very quick passage was made across the streak, and at half-past three the coast appeared in sight. At the same time rain commenced to fall, and as we steamed past the lighthouse on Ostend breakwater it came pelting down sharply. At a quarter to three the good ship was secured alongside the wharf, and out came the lost sheep looking white and miserable, one passenger, although not of us, who had sat on deck more dead than alive the whole way over, fairly dancing with joy at his release from the purgatory of sea-sickness. [3, Col. 2a–2b] Ostend to Bruges. While those unfortunate enough to be hampered with luggage stood by for the purpose of having it searched the rest of us secured seats in the train already drawn up alongside. It was then discovered that we did not start for half an hour, and the interval was turned to account by a  visit to the buffet. ''Cafe-au-lait'' was the general order, and mightily refreshing it proved to be. Everything comes to him who waits, but before the journey was continued sharp to the time mentioned, it was very patent that our descent upon Belgium in such numbers had attracted much attention. One dark-bearded "foreigner" who had watched us closely on the way across, actually grew so confident that he had exploited our movents that he grew bold beyond discretion. Coming forward with all the effrontery imaginable he rather startled us by asking, "Well, when is the 'mill' coming off?" In a twinkling one and all assumed a look of stony indifference, and on the question being repeated he was forcibly yet politely informed that we had nothing to do with any "mills." As we left the station our inquisitive friend was seen gesticulating to a belaced Ostender, evidently proud of his perspicuity. Thirty minutes' run through the flat and thoroughly soaked country brought the gable roofs of ancient Bruges in sight. Night had not yet darkened the streets, but there was mist enough to hide our movements to a great extent. It had been agreed that the brigade should split up as much as possible and spread themselves over the city. This was done in a great measure, Tom Dunning piloting my section across the  broad station-square to the Hotel de l'Univers. On the threshold I met Mick Taylor, who naturally looked somewhat aghast at the advent of so big a muster. It must have surprised him still more when others strolled in, and eventually the Britisher's party reached no less than fifteen. Fortunately our worthy host had plenty of available room, and after climbing up the winding stairs the whole troupe were comfortably housed. Water was at a premium, while soap could only be obtained by borrowing from the one or two lucky ones who had thought to bring '''that useful saponaceous compound''' with them. Entering the saloon after an outward and inward refresher, I ran across Josh Cosnett, and close behind the Brum stood, Frank Slavin, looming fine and large. The Australian Champion looked in grand condition, his face bronzed by the sea air and the toughening preparation he uses. Gently puffing a cloud from his Belgian weed, he greeted the arrivals cheerily, and was as skittish as a kitten, his hearty laugh resounding through the establishment. He had a very favourable passage across Channel the previous night, and amused himself by strolling around the city during the day. It was a piece of good fortune that not only could the ''garçon'' speak English fairly well, but at least two of my companions were conversant with the language of the country; negotiations anent dinner were therefore carried out with celerity. [3, Col. 2b–2c] Pugilism at the Piano. While '''awaiting the refection''' Slavin opened the piano which stood at one end of the ''salle-à-manger'', and dashing his lingers over the keys soon gave evidence that he was no mean performer on that instrument. Waltz, polka, and march all came as one to him. What a staggerer this would have been to the old timers, who never dared to allow a man in training such liberties. There was not the slightest sign of fear for the result of his coming encounter, and, in fact, Slavin appeared the least interested of the crowd. His piano selection whiled away the interval before dinner, at which the Australian presided. Taking his place at the head of the table Slavin entered into the fun, and no one would have conceived for a single moment that he had such a weighty matter on his mind as a fight. The repast was a lingering affair, and Slavin retired half way over the course, and betook himself once more to his favourite piano, which he wrestled with on and off during the remainder of the evening. While we were enjoying the good things under the roof of the Hotel Univers the rain had increased, and a perfect downpour succeeded. This had the effect of keeping the majority confined to the house, but several of the more venturesome spirits proceeded to explore the city, and they at any rate got a good drenching for their pains. The "pelting of the pitiless storm" continued the greater part of the night. Arrival of Jem Smith. The Champion of England, accompanied by Jack Baldock, Jack Harper, Jem Carney, and several other henchmen, came on from Lille at six o'clock, and arrived at Bruges about 8.30, taking up their quarters at the Hotel de Londres. Jem Smith, after leaving London on Friday, had travelled by easy stages to the Belgian frontier, so as not to miss a meal or proper night's rest and exercise between. He looked wonderfully well, having worked off much superfluous adiposity during the last few weeks' training. Unlike his opponent, Smith kept very quiet during the evening, and retired early. A meeting of the representatives of the men took place at a late hour, and in company with the owner of the ground and others interested, the final arrangements were made. I was present to assist at this necessary proceeding, and so perfectly had all the preliminaries been settled that there was very little left to be done[.] Owing to the presence of a mob of Birmingham men, who by some means or other had made their way to Bruges, there was fear of interference, but every precaution was taken to defeat anything disagreeable occurring. The behaviour of many in the streets during the evening was not calculated to assist those who desired to see a fair and square battle. Strict orders were given to the ''garçon'' to call us at 5.30 sharp, and to make assurance doubly sure many affixed their names on bedroom doors. Punctually to the moment came the rat-tat on the panel, and a hasty toilet was made by the light of the dip. A glance through the window reassured us with respect to the weather, the rain having ceased, but it was yet too dark to get any idea of the future. Even thus early the patter of sabots on the stones outside betokened the fact that Bruges, sleepy as it is said to be, was well awake. When the sounds from the famous belfry announced six o'clock [Col. 2c–3a] the bulk of the dwellers in the Hotel Univers had found their way to the ''salle-à-manger'', or "the manger" as "Pop" expressively named that apartment. Tea, coffee, fillets de bœuf, and chops were discussed, and the early birds had only been fairly started when with a cheery "Good morning, gentlemen," Slavin appeared. He lost no time, and was soon busy with knife and fork. Time flew by rapidly, and there were signs of an early daybreak. This hurried on the final preparations. Bills were paid, creature comforts taken on board, Slavin, with the greatest ''sangfroid'', seeing to his own business as unconcerned as possible. Our pilot put in an appearance shortly after the half-hour had chimed, and informed us that the other sections had already gone on. The March to the Battlefield. Breaking into groups of half a dozen the advance guard, led by an English resident in Bruges, pushed on, but before going two hundred yards there came a check. The railway had to be crossed, and just as the leading division reached the line they found the gates closed. Although opened in a couple of minutes it allowed the party to amalgamate, but they soon filed out again. Many streets had to be traversed, and in the now increasing light we were scanned by groups of workmen and workwomen who were on the way to the many factories in the neighborhood. Talking except in whispers was tabooed, so that our nationality might not be discovered, and without further incident a walk of twenty minutes or so brought us to the chosen spot. Entering the private grounds by a wicket-gate, there was light enough to see that the others were present standing among the trees. Four moving objects suddenly appeared as we crossed the garden carrying some white posts, which quite gave Joe Vesey a fright. The principals were hurried off to comfortable quarters near by, Smith having the stable to make his toilet in, while Slavin was accommodated in a barn. Proceeding towards a big plantation I found several quietly at work [3, Col. 3a–3b] Building the Ring. Between two belts of trees, formed chiefly of firs and beeches, was a clearing forty feet wide, and here the turf had been swept clear of the fallen leaves — in fact, a native, whose gigantic sabots caused much amusement, was still busy with rake and roller[.] Barney Sheppard superintended the pitching of the ring, an operation which took some time. Eight heavy stakes had been provided and plenty of rope, but the ground was very soft after so much rain, and wedges and guy-ropes had to be freely utilised. There being no tape, the distance was measured out by strides, and when eventually the job was finished it was plain that plenty of room had been allowed. The spectators amused themselves in various ways until, when the clock struck eight, all was in readiness. It was now broad daylight, and as several rustics on their way to employment caught sight of the, to them, peculiar proceeding, and stopped to more closely examine, the place did not promise to be free from interruption. All went well, however, and as the business did not concern them they passed on. There was some delay at this point, and it was close upon half-past eight when the men were reported ready for the fray. The following comprised the company round the ring: — Lord Mandeville, Lord Royston, Hon. M. Sandys, Mr Abington, Mr F. Kotchie, Mr J. Kilby, Mr C. Parsons, Mr Ike White, Mr W. Riley, Mr C. Morton, Mr Harris, Mr E. Bayley, Mr J. Lewis (Australia), Mr J. Vesey, Mr F. Hinde, Mr J. Fleming, Mr M. Taylor, Mr J. Calder, Mr G. T. Dunning, "Pop" Joy, R. Habbijam, G. ("Barney") Sheppard, Jem Carney, Tom Smith, Mangie [?] Hyams, Matthews, Summers, Boulton, and several others, including two or three reporters. Smith, accompanied by his seconds, J. Harper and J. Baldock, entered the ring, quietly going over to the south-west corner with hardly any notice. Baldock at once wanted to know why Slavin had not turned up, and was inclined to be nasty, when the Australian walked briskly to the opposite corner, having, without the customary teasing for choice of positions, allowed Smith to take the higher ground. Josh Cosnett and Bob Kirby accompanied the Australian Champion as seconds, while Mick Taylor superintended the arrangements in his corner. A loud cheer greeted their advent. There was a few minutes' delay after the men had taken up positions, owing to Slavin not being provided with a seat, and Baldock again wished to hurry him up, but matters proceeded peacefully. Mr Joe Vesey, who had been appointed to the unthankful post of umpire, took up a position on the lower side midway between the corners, and Mr J. Calder was selected as timekeeper. On either side of the referee Mr J. Fleming, umpired for Smith, and Mr W. Riley for Slavin, these preliminaries being quickly settled. The disposition of the officials made Slavin's corner appear the stronger, and to still further add to this, a large percentage of the spectators selected that side, so as to get their backs to the wind. Another, and, perhaps, a more potent reason was the fact that The Dreaded Birmingham Division had massed themselves behind Smith and along the higher aide. They had long caused considerable fear among the spectators, but were not so noticeable until they stationed themselves in a phalanx near the Englishman. While the corners were being arranged several of the "boys" worked their way round to Slavin's quarters and stood menacingly by. Mick Taylor was too old a bird to be caught, and with the assistance of Prank Hinde, Lord Mandeville, and one or two trusty friends, guard was kept over the water and other articles. Every necessary for the two athletes had been provided by the proprietor of the grounds, so that there was no trouble on this score. Smith was wrapped in a heavy frieze overcoat, while Slavin, who, during his sojourn in the barn had been divested of his heavy moustache — a loss he deeply regretted — was also covered by a big ulster. It was now half an hour beyond the time fixed for the commencement of hostilities and broad daylight, even the belfry of Bruges being plainly visible in the distance, but curiously enough not a soul beyond the pugilistic party was anywhere near the fighting-ground. At last everything was ''en règle'', and in perfect silence Mr Joe Vesey came forward and said, "I hope all those present will keep quiet and help me all you can," at which brief speech there was a chorus of "hear, hear," especially from Slavin's corner. At 8.35 Belgian time, the two antagonists met in the centre of the arena and shook hands, the seconds, as in time-honoured fashion, doing likewise, forming what is known as the Maltese Cross. Smith, who partook of a draught before commencing, was the first to peel, and although he looked fine enough in the face, when his covering had been removed he appeared fat, although nothing like so obese as when he met Peter Jackson. The Englishman wore short white drawers and green socks, while a strengthening plaister adorned his waist. Slavin looked the picture of health and strength, having trained down very hard, his muscles standing out most prominently. He was clothed in long black drawers and blue stockings, and, like his opponent, wore a deep plaister. In addition Slavin used a suspensory belt loaned to him by Charlie Mitchell, who had found it of great service in his fight with John L. Sullivan. Under weather, which for the business in hand was simply perfect, and particularly warm for the time of year, there was, as far as could be seen by the uninitiated, every prospect of a good [Col. 3c–4a] fight. This was doubted by the majority, the presence of the crowd of roughs betokening trouble when once the battle should commence. The Call of "Time" At twenty-five minutes to nine brought everyone to the ropes, and amid perfect silence the pair of pugilists shaped for the encounter. Slavin from the first smiled confidently, while Smith looked serious. Neither appeared in any hurry to begin, and sparring for an opening, Slavin gradually worked Smith back into his corner. Fifty seconds elapsed before a blow was struck, but this had not passed without our opinion being confirmed, that we might expect trouble from the Brums. Smith's seconds set the ball rolling by hurling the vilest of epithets at the Australian, and their example was followed by their supporters. By some oversight the seconds had not been ordered out of the ring, but attention was at once called to the fact, but, constituting himself referee, Baldock refused to obey the order to retire when given by the appointed officials. This boded ill, and before a round had been fought it was pretty plain to all that Slavin would have little chance of victory. Had the objectionable party confined themselves to vituperation this might have been borne, but going from bad to worse we soon witnessed a scene that was not only a blot upon the good name of Englishmen as lovers of fair play but one never equalled even in the worst days of the ring. Slavin was the first to lead, but only tapped his opponent lightly on the face, and he had the best of several exchanges, but did not put forth all his power into his left-handers. Smith's blows were also comparatively harmless, until the last half minute, when they got to close quarters and hammered away sharply amidst a chorus of yells from the Smithites, until they fell together. No sooner were the two men down than Baldock rushed up, and in picking his man up knelt on Slavin. A foul was claimed, but no notice was taken of it, although it was very palpable. Warnings were given to the Australian not to go into Smith's corner, but without avail, and he entered upon the second round full of pluck and confidence. Language — if such filthy expressions as were levelled at Slavin could be so designated — of the violent kind greeted him on facing Smith, and this was not confined to the hired mob. Those from whom at least fair play might reasonably have been expected indulged in blasphemy and rowdyism even more pronounced than that of the others. To still further disconcert Slavin a claim of first blood was made. The moment he walked across the ring Smith worked up close at once, and on rushing in was met with the left on the mouth. A brief struggle ensued before they fell together, Smith while on the ground spiking Slavin in the thigh. A foul was again claimed but the referee was so badgered that he could hardly have known where he was, and no notice was taken of the occurrence. In the third round, again a short one, Smith was Knocked Down By a cross on the jaw, and he came up looking the worse for wear next time, while the blackguards in his corner were more threatening than before. Smith again waited in his corner, and, nothing daunted by their menacing attitude, Slavin boldly went after him. As he advanced he was assailed by the miscreants, who now saw that Slavin was getting the best of it, and when after another round had been fought, in which Smith began to blow freely, the Australian was near the ropes he received a blow from one of their number. Every time Slavin was forced to fetch Smith out of his corner, where at this early stage the ropes had been loosened. In the sixth round Slavin now warmed up, sent home a hot left-hander on the right eye, from which the ruby fluid ran freely. This he followed up by some sharp work, eventually fetching Smith down with a vicious right-hander. This treatment of their "Champion" did not suit the villanious [sic] coterie, and Slavin went across the ring next time at great risk. Smith worked Slavin round to the ropes, and while there the dastards held him for the Englishman — save the mark! — to punish, and there was an indescribable scene of confusion. Still, Slavin would not be denied, and in the eighth round sent the right heavily on the jaw, and fairly knocked Smith off his legs. In the following round Smith received a smash on the mouth, but Slavin was terribly handled by the outsiders, who punched him freely while in holds. Smith up to this had hardly made a mark on his antagonist, and beyond a cut on the lip he showed no signs of punishment, but the cowardly ruffians who assisted the "Champion" wounded him severely. So vile was the conduct that the referee was, like every one else had long been, thoroughly disgusted, and he tried without avail to put a stop to it, calling upon Harper to "be a man." Smith was generally short in his deliveries, and Slavin, paying more attention to the body had doled out some telling work. In the twelfth round Smith was felled in his corner, and this brought a crisis. The latter broke away from Slavin's attempts to get on with the left until he was almost backed up against the corner stake, when the Australian dashed the left on the face. No sooner was he fibbing away than the ruffians crowded up and showered blows on his head. In the midst of the mélée a cry of "Here they are" was raised, and A Stampede Ensued from Smith's side. It was evidently a concerted plan, as when the leaders found that no one stirred from Slavin's corner they actually came back, and pointing to the roadway, yelled, "There they are, there they are." By this time Smith had run a hundred yards away towards the house, and Slavin's party, under Rule 26 [?] claimed the fight, but to no purpose. The confusion ensuing upon this manoeuvre looked like putting an end to further fighting. Slavin, who had shown not only admirable pluck and judgment, but also kept his temper, was quieted down when he thought there was yet a chance of winning. Smith was fetched back again, and time was called. Slavin, before putting his hands up, addressing his remarks to the crowd at the other side of the ring, said, "Are you Englishmen? I am an Englishman, and only want fair play." The fight then proceeded. Seeking to settle matters now that he had Smith weakened, Slavin went right over to Smith, and planted the left sharply on the body twice, and then dashed in with both bands, landing on the jaw. As they closed someone of the brutal mob struck Slavin on the right ear again with a "duster," the referee saying, "I saw that." As Slavin threw Smith and the mob again became aggressive, Vesey, who could stand it no longer, said, "I refuse to act any longer. It is impossible for this man — pointing to Slavin — to get fair play." The referee concluded by giving the decision, "It's a draw." The mob heard this with fiendish delight, and at once cleared off from the ring-side. Slavin could hardly contain himself, shouting "There is not a man round the ring can kill me. l came 16,000 miles for a fair fight, and why don't you give a man a chance." There was no help for it, and the latest fight for the Championship ended under circumstances which brought the greatest discredit upon those who were responsible for [Col. 4c–5a] the presence of the wretches, who were prepared for any villany [sic] to prevent Smith being defeated. Not satisfied with their performance at the ring-side, they followed him to his temporary dressing-room, but were soon persuaded to leave him alone, which was perhaps fortunate for at least some of the party. Jem Smith had a carriage in waiting for him, and was rapidly carried off to the town, where it was intended to stay for some hours. There was a rush to the telegraph-office to send messages to interested friends, but only a few minutes were available, as at least a third of  the party intended Making All Speed Homewards. The Ostend train was waiting in the handsome station, and there was no time to be lost[.] Slavin, who walked the whole of the way back into town, was hurried into a first-class compartment, where he made himself comfortable in a corner with a cigar. There was a crowd of hangers-on in and around the station, who evidently were by this time aware of the nature of the morning's work, but without further incident the train steamed out of Bruges. Arriving at Ostend at 10.15 we found the Comte de Flandres ready to receive passengers at the quay-side. This boat is not to be compared with the Princess Henriette, being much smaller and less seaworthy. Slavin had a deck cabin prepared, and therein held a levée, champagne and other sparking wines being ordered up. The Australian, under the careful hands of Mick Taylor, had the cruel wounds inflicted by the ruffians at the ring-aide attended to, and by the time the boat was clear of the offing Slavin was fixed up in shape and paraded the deck. Everyone talked of the fight and its terrible surroundings, and nothing but the severest condemnation was accorded the Englishman's party. One gentleman, who was wearing Smith's colours, was so disgusted that he threw them overboard, and replaced the kerchief with one bearing Slavin's monogram. Dover was reached in due course, a big crowd awaiting Slavin's arrival on the pier, but, shorn of his moustache, he was hardly recognised. He proceeded thence to Margate with M. Taylor and J. Cosnett, where another ovation awaited him. The other portion of our company journeyed direct to London, and on detraining at Cannon-street there was a crowd collected to gather news from the seat of war. Smith was to leave Bruges during the evening, and all being well will arrive in London early this (Tuesday) morning. </blockquote> ==== THE FIGHT. ==== <blockquote>First Round. Slavin left his corner quickly, with a firm, determined step. Smith was much slower in his movements, and the Australian had almost reached his opponent's corner when the men were face to face. The disparity in the height of the men was very marked, Slavin standing well over the Englishman. Each wore a deep strengthening plaister, whilst Slavin, it may also be added, made use of the suspender worn by Charley Mitchell in his memorable fight with John L. Sullivan. Full of confidence, and evidently in splendid condition, the colonial looked every inch a fighter, his length of reach, and lithe, agile movements contrasting strongly with the lumbering position struck by Smith. Though fairly clean in the face Smith looked very heavy below, and undoubtedly carried too much flesh for the business he had taken in hand. Great caution was exercised on both sides, and it was seen that neither man intended to throw the slightest chance away. Weaving in Slavin feinted with his left, but Smith was quickly out of danger, and in turn Slavin dodged an intended blow from the Englishman's left. In this manner fifty seconds sped on, after which Smith got in lightly on the month. Exchanges of a light character followed, Slavin reaching the body and Smith the face. Subsequently the latter, who seemed considerably puzzled by the Australian's style, several times led out of distance at the head, Slavin on each occasion breaking ground very prettily. At last the men got to close quarters, where some sharp infighting ensued. Slavin made the body his mark, where he put in heavy work with the right, Smith in the meantime visiting his opponent's head. The Australian's blows seemed to take the most effect, and the round ended by Slavin having the worst of a fall. Time, 2min 30sec. Second Round. No sooner had the men been removed to their corners than Jack Harper called out in a very loud voice, "First blood," a claim which was of course allowed, the Colonial showing a slight trickle from the lips. On "Time" being called the pair were quick to scratch, that is to say, Slavin walked right across to Smith's corner, the Englishman refusing to come out. A long opening spar took place, but at length blows were exchanged, nothing very serious being done, and closing, the pair had a slight struggle, both falling together. Whilst on the ground a good deal of kicking and struggimg was indulged in, and whether intentionally or no Smith spiked his opponent on the inside of the left thigh, tearing his drawers, and causing the blood to flow considerably. Uproar followed, the round lasting 20sec. Third Round. Though up to this time neither man had sustained much punishment, the exchanges not having been very severe, Smith was always carried to his corner, Slavin, on the other hand, walking back to his. At the beginning of the third round the referee ordered the seconds out of the ring, but they declined to go, saying that official had no power to order them to do so. On starting Smith forced the fighting, and leading with the left, hit Slavin upon the body. This he followed up rapidly with two more in the same place, all light hits, and some rapid exchanges followed, the Colonial using the right with effect upon the side of the head. Smith paid principal attention to the body, but at length Slavin, drawing back the right, shot it out straight from the shoulder, catching the Englishman fair on the point, and sending him down all of a heap. This magnificent delivery put the Slavinites in excellent spirits, the Colonial smiling all over his face, while the Smithites looked serious. First knock down blow was claimed, and, of course, allowed for Slavin. Time of round, 24sec. Fourth Round. Smith rose from his seat looking very serious indeed, Slavin, on the other hand, being in much better spirits. At the same time a suspicious movement was noticeable among the brigade of Birmingham ruffians, and one of them came round to the Colonial's corner with no good intentions. Had it not been that Mick Taylor and Frank Hinde kept zealous guard over all the water provided for the use of the combatants, there is no knowing what fiendish trick might not have been perpetrated. The remainder of that party stayed in Smith's [Col. 5c–6a] corner. As for the seconds, all remained in the ring. The opponents sparred for the first twenty-five seconds, and at length Slavin, getting an opening, led out of distance at the body. The Englishman seemed glad to have a blow, but Slavin weaving in delivered lightly with the left upon the cheek. Again the pair faced each other in the centre of the ring, and Slavin went for his man, and feinting with the left, just failed to bring off the right, Smith skipping out of the way. Again the Antipodean feinted with the left, and following up the charge, this time successfully caught Smith flush on the mouth. Then quick as lightning getting to close quarters, Slavin delivered heavily right and left on the body, Smith being very slow in responding to this vigorous attack. He had, however, other assistants, for a vile ruffian from over the ropes deliberately struck Slavin a blow on the head. A shout was at once raised, but when charged with it the rascal denied that he had done anything. A scuffle ensued between the men, and to escape from the difficulty Smith cross-buttocked his opponent, who fell, the seconds, rushing to the centre of the ring, falling over them. Time, 1min 15sec. Fifth Round. "Don't go into his corner," urged Taylor and others of Slavin's party to their man, but nothing could restrain him when time was called, and, springing up with a bound, he advanced towards the opposite corner, where Smith was standing up. Once or twice the Englishman seemed inclined to go into the middle of the ring, but was always prevented by his yelling seconds, who stood on either side of him. On toeing the mark Slavin appeared with a suspicious-looking redness of the left eye, caused by the miscreant above referred to. Though appealed to the referee declined to give any decision on the subject, and the fight proceeded amidst some of the most horrible language it has ever been our misfortune to listen to. This proceeded entirely from Smith's corner, who, seeing that their man was already beginning to blow and look distressed, prepared to stop at nothing. Slavin, after wasting a second or two, followed Smith into his corner. One or two exchanges, quickly delivered, of a light nature took place, and the Colonial got in on the body with the right, following up with the same on the head. This Smith considered ample justification for sinking gracefully upon the ground, the round having lasted only sixteen seconds. Sixth Round. Smith came up blowing Iike a grampus, whilst on the other hand, Slavin, seeing his advantage, was eager to begin. Of course, it was necessary to go right over into Smith's corner, that worthy not moving two feet from his chair, whilst the shouts, jeers, and din which greeted the Australian were of an inexpressibly disgusting nature. Still, nothing daunted, the Antipodean followed his man up, Smith leading at the head. This Slavin easily turned aside by a lithe movement, and in turn was stopped by Smith. Resuming, Slavin banged in the left on the mouth, Smith countering on the body. A smart counter ensued, and at this juncture the referee entered the ring, making a fruitless appeal to Smith's corner to behave themselves. Nothing, however, could silence the foul language which proceeded from that quarter. Once more facing each other, the Australian shot in the left fist heavily on Smith's left eye, opening a severe cut, which bled freely. Some vicious infighting followed, and Smith twice got the right in upon the head. Slavin countered with a terrific right-handed blow on the eye, knocking Smith down. Time, 1min 20sec. Seventh Round. In vain did Slavin's friends implore him not to go into Smith's very "warm corner." It was plain that if he did not do so there would be no fight, Smith never coming many feet away from the rascals who had been hired to protect him. Getting to close quarters Smith delivered the left lightly upon the face and banged in directly afterwards the right on the body. Slavin did not see the Englishman having matters all his own way, and a desperate rally took place, during which Smith fought Slavin on to the ropes, and there held him. Here was a grand opportunity for the miscreants, who did not fail to make use of it. One of them kicked Slavin repeatedly, and others beat him about the head, whilst, naturally, Harper and Baldock were yelling at the top of their voices. The confusion was something terrible, and the ring looked very much like being invaded. The ropes in Smith's corner were pulled right down, so that an entrance might be effected at any moment, and it was a relief when the pair wrestled and came down in a dog-fall together, the round having lasted one minute. Eighth Round. Crossing over at once to the only place where Smith was to be found (''i.e.'', in his own corner), Slavin worked his opponent round to the side of the ring, and there let him have the left lightly upon the face. Standing at this moment close up to the ring-side, the Colonial received a couple of smart blows from a stick which a ruffian coward carried.  An immediate cry went up, and the individual finding himself under very close observation immediately slunk behind. Taking not the smallest notice of these interruptions Slavin pursued his legitimate opponent, both Smith's following him about and jeering in his face. Again the referee entered the ring, and cautioned the seconds to move away. This had very little effect, and in the midst of half-arm fighting of a very severe kind, Smith, who was receiver-general, judged it advisable to seek mother earth. Time of round, 1min 30sec. Ninth Round. This was altogether a very curious round. When time was called Slavin got up to find his opponent, who barely moved a foot from his chair, and this fact should have been sufficient warning that something awkward was intended. In the corner the two sparred for about fifteen seconds amidst a horrible din. Finding that the Englishman was in no hurry to begin, Slavin made the first movement, and landed with the left lightly on the head. Following up this, he brought the right round heavily on the dial, making Smith wince, but a second blow in the same quarter was avoided. Still in the corner, the pair got to half-arm fighting, once more bringing them close to the ropes. The Birmingham mob here set about Slavin with great brutality, kicking him and punching him on all parts of the body. The referee, though appealed to again and again, took no notice, though admitting that he saw what was going on. Getting away from the ropes Slavin let go the right, and, reaching Smith's mouth, caused the blood to spring forth profusely. This last blow sent Smith to grass, the round occupying 50sec. [Col. 6c–7a] Tenth Round. The Champion of England by no mean relished the treatment received in the last round, and at the expiration of thirty seconds was puffing and blowing freely. He attempted to spar for wind, but the Australian seeing his advantage bored in when he could find an opening. Delivering right and left, and receiving only slight returns from Smith, the Australian pulled his man over, and the round terminated in 40sec. Eleventh Round. Neither was quite so quick to time, and Harper, noticing that, said, "This is not a two-round job, Patsey." Something like fifteen seconds was spent in sparring. Following Smith up the Australian failed to get an opportunity for some time. At length he put his hands down and invited Smith to "Come on and have a round." This was evidently not a particularly pleasing invitation to the Champion, as he remained in his own corner. Not to be denied, Slavin went after his man, but a left-hander meant for the head was put aside by Smith. At the end of a minute Slavin landed heavily on the Englishman's left cheek, a great red blotch immediately appearing. A rapid exchange followed, and Slavin was again home on the body. A heavy blow on the mouth from the Antipodean sent his opponent to the turf, the round having lasted 1min 35sec. Twelfth Round. A great change was noticeable in the appearance of the rivals on meeting each other for this round. Smith was showing signs of punishment on the face to a very large extent, his left eye being cut, his lip split, and there being a number of marks of Slavin's handiwork on his face. He was very distressed, and blowing heavily. On the other hand, Slavin, beyond the bad left eye (not done by Smith, but by one of the gang of hirelings), had apparently nothing the matter with him. Springing up brightly to his work, the Australian roamed about the ring until he found Jem Smith secreted in his own corner, only just away from his chair. The Australian reached the mouth lightly, and endeavoured by this means to draw his opponent out, but failed to achieve his object, Smith being strenuously warned not to move away from his seconds. The corner was encroached upon by Smith's crew, Harper and Baldock this time being almost between the men. The tumult was very great, but it seemed impossible to daunt the Sydney man, who followed Smith up, though little harm was done. Sparring was the order of the day until Slavin worked in with the left, delivering heavily. With great rapidity he drove the right with terrific force right on to Jem's chin, knocking him clean off his pins, and ending the round. Time, 1min 30sec. Thirteenth Round. Smith came up thoroughly dazed, the terrible blow in the last round having taken a lot of the steam out of him. The Birmingham gang, seeing that this was the case, got all of a heap in Smith's corner, and though Slavin was most earnestly advised to keep away, he would not do so. Smith stood just by ''his'' chair, and going right up to him, Slavin let out with the left, and bringing round the right. Both of these visitations Smith missed, but not so in the case of a second smack from the right, which made Jem wink. However, turning round, the Englishman forced his opponent up against the ropes, and here occurred one of the most disgraceful scenes ever witnessed at a pugilistic encounter. Some villain drove his knuckle-dustered fist right on to Slavin's ear, cutting it almost in two and causing the Australian to exclaim, "Oh!" Other of these demons kicked him, a scene of indescribable confusion ensuing, in the midst of which the men continued fighting until the pair came down together. Time. 1min 28sec. No sooner was the round finished than cries were raised of "Here they come: the coppers, the coppers; and all Smith's gang, including his seconds, rushed away from the ring, at the same time calling upon Slavin to do so likewise. As for the Champion of England, he headed the runaway party, though nobody could detect the shadow of a "blue." The Australian never left the ring, much to the chagrin of the Smith party, who, seeing that the referee was being called upon for a decision, returned rather sheepishly. Baldock was in a dreadful fright, thinking the battle has been lost, but when the words "fight on" came he and his friends were very delighted. Fourteenth and Last Round. When "Time" was called Slavin folded his arms and waited for Smith to "come on," but Mr Smith didn't want to come on, and remained in his corner. Seeing it was impossible to make him stir Slavin once more crossed over, and a spar of nearly a minute took place. Then Slavin drove home the right on the body heavily, and the pair closed in Smith's corner. This gave another opportunity to a miscreant to strike Slavin on the head. Others in the gang were not slow to follow, and again the round ended in horrible confusion. Time. 2min 15sec. No sooner was this round over than the referee called out. "I refuse to act any longer. It is impossible for Slavin to get fair play. It's a draw." Then, going up to Slavin he said, "I will not stay to see you killed." The Antipodean stood up and exclaimed, "If you are Englishmen why don't you give me fair play? I have not had fair play." After this came a stampede. Remarks. Judging by the disgraceful proceedings recorded above, we are surely near the end of what are known as "fights in the old style." That such a scene as that witnessed yesterday could possibly be enacted by any man with a drop of Christian blood in his veins seems almost incredible. Take the picture. An athlete, one of our stock, journeys 16,000 miles to measure blades with the best we can produce. Confident he will receive fair play in a land which boasts of nothing foul, he, after trying in vain to ratify a match to meet England's Champion, to be decided before an impartial and unbiassed crowd, puts down his hard-earned hundreds and meets our man in the style the latter insists upon. And with what result? Battling under unheard-of difficulties, not fighting one man but nearly a dozen, he narrowly escapes being murdered, and in the end is robbed of a victory he had won not once but in almost every round contested. If the nail driven hard into the coffin of pugilism yesterday is not the last, it is indeed ten thousand pities. Nothing can flourish, however, without support, and, providing the remarks passed by the majority of the spectators at the ring-side at San Michael are of any account, it will be many a long day before a knuckle-fight receives the patronage of the "upper crust." Slavin, we say, narrowly escaped murder, a fact proved by the words the referee, who, as well as others present, stood in fear of his Iife. One gentleman, an old ring-goer, affirmed he had never witnessed such disgraceful proceedings, and when the ring was finally cleared a feeling of relief was manifest on all sides. Unfortunately we are called upon to say that the riot and murderous intent were all in Smith's corner. On the other side not a man was present against whom a breath of suspicion could be raised. Opposed to Slavin was a hired gang of desperadoes ready to commit any act necessary to serve the ends of those by whom they were engaged. Terms of imprisonment had been worked out by each, and, prepared with knuckle-dusters, revolvers, and knives, they appeared ready to butcher the company at the raising of a finger. In face of all this the Australian fought his way to a moral victory. Almost from the outset Smith was outmatched, and beaten at the game considered his own. Sticking to his corner, of course by order, he showed none of his boasted bull-dog pluck and courage. His dreadful body-blow was easily put aside by Slavin, whilst instead of being "bashed" on the ground and battered out of shape, the Australian fairly held his own in wrestling. We are not blaming Smith for the doings of the miscreants present, and we also know that he was acting under orders by staying in his corner and affording them every opportunity to kick, strike, and prod the Australian, but it was altogether un-English to hold Slavin on the ropes whilst the mob belaboured him with "dusters" and sticks. Smith was, besides being in poor condition, slow and ponderous. After the third round his chance was hopeless, and his supporters were surprised at the form shown by Slavin. Contrary to general expectation, the Cornstalk proved himself far and away a better knuckle-fighter than a "glover." With his long reach he did great execution by left-handed deliveries, and the way he toppled Smith's fourteen stone over with the terrible right was a sight [p. 3, Col. 7c – p. 4, Col. 1a] that would have gladdened the heart of old Bill Richardson. In a word Slavin was entirely a different man from the Slavin that fought Bill Goode. Brimful of confidence he faced dangers that few would have encountered, and had the battle been conducted on fair lines he would have been Champion of England and Australia in less than half an hour. In all his battles he has never known defeat nor met with a knock-down blow. Yesterday it was not once found necessary to carry him to his corner, and as all the fighting was done in Smith's corner he must have walked a matter of eighteen yards each round. Slavin has a method of his own in pugilism. Possessed of staying powers, or "bottom" of a most remarkable character, he tires his man and then fights him. Yesterday, providing he had met with no punishment from outsiders, he would have left the ring almost without a scratch, and, as he himself said at the finish, "he was just getting warm." Remarkably clever on his feet, Slavin was in and out with the activity of a feather-weight, and feinting with the left, which he brought forward, he sent his right under the ribs with crushing effect. For some time past it has been an open secret that if Smith did not win he would surely not lose, and it is a blot on the proverbial love of English fair play to think that a mob should have been organised, and such a cowardly attempt made to rob a stranger amongst us of a victory so hardly earned and so clearly deserved. From the first the rules were broken by allowing the seconds to be in the ring whilst the fight was in progress, and although Smith's men threw everything in the way of the Australian, Cosnett and Kirby never transgressed the rules of fair play. Why the referee did not award the fight to Slavin when Smith left the ring in the thirteenth round can only be explained by his fear of the consequences that might follow. Bearing on this subject, Rule 26 says:— "That if a man leaves the ring, either to escape punishment or for any other purpose, without the permission of the referee, unless he is involuntarily forced out, he shall forfeit the battle." Rule 24 is also plain enough in all conscience, "That any man voluntarily quitting the ring previous to the deliberate judgment of the referee being obtained shall be deemed to have lost the fight." Undoubtedly Mr Vesey lacked firmness, and perceiving this at the start, the "boys" and Smith's seconds, not to mention another couple who used their hands and feet at every opportunity, saw the game was in their own hands, and simply did as they liked. From first to last the proceedings were of a most disgraceful character, and the result showed plainly the reason why Smith's side objected to all the referees nominated by Slavin. Several gentlemen present, in fact all disinterested spectators, expressed their disgust at the treatment meted out to Slavin, and it was suggested on the return journey that a subscription be opened to provide funds for a testimonial to the plucky but unfortunate Colonial, particulars of which appear elsewhere. Even after the fight Slavin's assailants could not let him rest. Not content with robbing him of victory, they followed him to his place of dressing, but a determined front shown by Mr Taylor, Cosnett, and Kirby kept the blackguards back. These are well-known, and will, we believe, shortly meet with the punishment they so richly deserve. One rough made a rush for Lord Mandeville just before the close, but "Kim" soon showed he could hold his own with the "boy," who beat a hasty retreat at the "sight" of six-inch "Jack."<ref name=":1" /> (4, Col. 1a) We now take our leave of this unsavoury affair, which will probably be the last of its kind — "a Championship knuckle fight." The Englishman's boasted love of fair dealing appears lost to the professional fighter, and the sooner "merry mills in the old style" die out, and the hanger-on has to earn his living in some other way, the better. Slavin will visit London today. He leaves Margate by the 12.15 train, and will arrive at T<small>HE</small> S<small>PORTSMAN</small> office about three o'clock. Smith had a nasty lump on the jaw and left cheek, whilst his right eye was cut open deeply. In addition to this the punishment he sustained on the body was of a severe character. Slavin, on the other hand, only received a cut lip until after the fourth round, when the rowdies joined forces with Smith and smashed his eye during a mélée. After all their kicking and the free use of "dusters" the Australian only suffered from a badly-cut ear and the before-mentioned damaged eye. It may be stated that not a single bet was made at the ring side. [4, Col. 1b]</blockquote> ==== SLAVIN'S OPINION OF HIS TREATENT. ==== <blockquote>His Future Plans. On the return journey to England yesterday Slavin was the centre of attraction. At Ostend, where the tale of the fight had somehow or another been told, he was met by an eager crowd, and on the boat he held quite a ''levée''. Though at first somewhat disappointed at being robbed of the title of Champion and 500''l''. so well within his grasp, the Australian, surrounded by old friends, and new ones gained by reason of his straightforward conduct, rapidly regained his spirits. With the inner man refreshed by a steak, washed down with some of Heidsiek's [?] best, Slavin, a Havana between his lips, quickly got on good terms with himself and the rest of the  party. Much sympathy was expressed on all sides, and in the course of conversation with a S<small>PORTSMAN</small> representative Slavin said:— Of course, I feel a bit cut up, because I had my man beaten[.] Did you expect any trouble at the ring side? Slavin: Yes, I was prepared for that, as I was constantly receiving letters of a threatening nature, and though these things as a rule are of no account, I had reason to believe there was some truth this time. Besides, I had not forgotten the affair at Astley's Theatre. Do you feel any effects of the fighting? Slavin: The fighting? I feel nothing of what I got from anyone in the ring; it's what those beauties gave me outside. The only time Smith hit me in anything like form was on the jaw. Why did you persist in going to his corner? Slavin: I wanted to get the affair over and enjoy my Christmas dinner, and I knew if the fighting was left to Smith I should want it served in the ring. Of course you heard a mob was got together for Smith? Slavin: Yes, I knew all about that, but I relied on British fair play, and expected the referee to do his duty. Directly I got in the ring I saw what the game was, and knew my only chance was to knock Smith out. What do you think of Smith? — Well, I think so much of him that I'll bet him 200''l.'' I stop him in six rounds, but we must have no more private shows. I've had enough of that business. [4, Col. 1c] I suppose you have a poor opinion of English fair play? Slavin: I have been treated like a prince generally, but I can see the fighting men are easily led astray, and I expected trouble directly Smith objected to a referee. If we served an Englishman in the same manner in Australia we should get drummed out of the town, and rightly too. What are your plans for the future? Well, I shall stay in England some time and challenge Sullivan, and you might as well cable it over to America for me. With the gloves? Slavin: No, I went to fight him with the knuckles. I think I should get fair play out there. You prefer the old style to the new? Slavin: I am fond of boxing, but the other is my game, and though not a boaster I fear no one — that is if I can have fair play. Shall you give any exhibitions? Slavin: I may perhaps make a tour round the country, and very likely visit Ireland. You put on weight the last week? Slavin: Yes, I gained eight pounds and felt grand; in fact, just up to dick when Smith bolted. What do you think of our seconds? Slavin: Well, I'd like them to have a job in Australia. They'd never come back again. When do you propose visiting London? Slavin: I'll come up to-morrow and call at T<small>HE</small> S<small>PORTSMAN</small> Office about three. A stroll was now taken on deck. [sic] and reaching Dover Slavin was met by some friends from Margate, who carried him off to the train in triumph. </blockquote> ==== A Testimonial for Slavin. ==== <blockquote>So impressed were some noblemen and gentlemen with the pluck and ability shown yesterday by Slavin, and at the same time thoroughly disgusted at the treatment he had received, that it was decided whilst crossing the Channel on the way home to open a subscription on his behalf. The donations are limited to 2gs, and the following amounts have been already promised Mr G. T, [sic] [Col. 1c–2a] Dunning, T<small>HE</small> S<small>PORTSMAN</small> Office, Fleet-street, who has been requested to act as honorary treasurer to the fund: [names set as unordered list to save space, last 3 column headers: £ ''s.'' ''d.'' The maximum donation was 2 guineas, which would be 2£ 2''s.''] * Lord Mandeville 2 2 0 * Lord Royston 2 2 0 * Hon. Michael Sandys 2 2 0 * Mr Fred Ketchie 2 2 0 * Mr Ike White 2 2 0 * Mr W. Riley 2 2 0 * Mr C. Parsons 2 2 0 * Mr J. Kilby 2 2 0 * Mr Frank Hinde 2 2 0 * Mr J. Calder 2 2 0 Any contributions sent to the hon. treasurer will be duly acknowledged in T<small>HE</small> S<small>PORTSMAN</small>, which in a couple of days will contain the names of a committee now in course of formation. In the London clubs yesterday the opinion was very general that Slavin ought to be compensated for the loss he had sustained in consequence of the ruffianly tactics pursued in Smith's corner. The utmost indignation was expressed in reference to the treatment the Australian had received at the hands of so-called Englishmen. We have received a number of letters on the subject. The following is a sample of them: To the Editor of T<small>HE</small> S<small>PORTSMAN</small> Sir, — I have no doubt that many Englishmen will have read with regret the disgracefully unfair treatment that Slavin met with in his encounter with the  "Champion of England" to-day. I trust that a subscription will be started to show him in a substantial manner that the sympathy of most Englishmen who take an interest in boxing is entirely with him. If you are prepared to receive subscriptions I shall have much pleasure in subscribing a guinea, and in collecting those of many friends who will be glad to subscribe. — I am, Sir, yours faithfully, C. B. C. Royal Thames Yacht Club, December 23. [We refer our correspondent to the paragraph above. — Ed. T<small>HE</small> S<small>PORTSMAN</small>. ] [sic bracketed interpolation] [4, Col. 2b] </blockquote> ==== Eyewitnesses Interviewed. ==== <blockquote>A representative of T<small>HE</small> S<small>PORTSMAN</small> was at Cannon-street station yesterday afternoon to meet the Continental express, in which a goodly number of those who had witnessed the fight made their return to town. The train was somewhat late, and did not steam into the station until a quarter to six, when our reporter singled out several well-known "sports" (including more then one scion of a noble house) for a few minutes' chat. Asked as to how affairs happened at the outset, one and all agreed that it was plain a row was meant, the demeanour of a certain section of the party, which did not number more than forty, being particularly noticeable. "How did the combatants' seconds behave?" — "Well, after the first round, it was evident that Smith would soon be at the mercy of his powerful opponent, and his seconds very soon perceived this state of things. In the initial round Harper came down with some force on the Australian's chest, while in the next bout Slavin came in for some rough treatment at the hands of Baldock, the Champion evidently suffering with one of his eyes." "What form was the Englishman displaying?" — "From the outset he made a miserable stand, and was plainly afraid of his rival. He fought as a coward, and by the tactics adopted by several of those at the ring side Slavin was fighting against great odds. Every time he got into Smith's corner he was met with remarks of a most uncalled-for character, and had to be very sharp to keep at arm's length of several rowdies, who, as the fight proceeded, became extremely noisy." "How do you account for such a noisy corner at the back of Smith?" — "Although they did not number more than eight, they were some of the worst characters known, and had undoubtedly been commissioned to play the part they did. This was most disgraceful, inasmuch as they not only made Slavin a mark for the knuckledusters and other weapons they were armed with, but likewise made tracks for individual spectators who ventured to express their indignation at the course of proceedings. One rough, more venturesome than the others, "framed" [sic double quotes] up to a familiar figure at boxing tournaments, but on the latter producing a long bowie knife, accompanied with a few words of a somewhat emphatic nature, the villain rejoined his party." Are these men known at all?" — "Yes, they are mostly from Birmingham, and are of the lowest order. It was reported that more than one had been kept at the country's expense, one for a very lengthy period." "Was not this sort of trouble expected?" — "It had been given out by one influential patron of the English Champion that there would be an absence of rowdyism, but it was also stated on good authority that certain roughs had been specially engaged, so that trouble was naturally anticipated." In reply to questions as to how the contest proceeded, it was the opinion that the thirteenth round would be the last, as Smith's party made a determined effort to bring about an undesirable finish. On the two fighters getting to close quarters more rough work ensued, and on some pretence Smith left the ring. Slavin, however, stood his ground manfully. "How did the crowd behave towards the finish?" — "There was a lot of excitement on all sides, but the only fear was that the rough element would resort to extreme measures in endeavouring to save their Champion. Others were ready to insult the Australian by using most filthy language towards him, and altogether affairs began to look serious." "Is it true that attempts were made to tamper with the water used by Slavin's seconds?" — "Yes! a man was noticed to be hovering about in that quarter, but, fortunately, his efforts to drug the fluid were of no avail." "Did Smith deal out much punishment?" — "His blows lacked the force of his rival, and when the referee gave his verdict as a draw the Australian looked very little the worse for his exertions, and could have fought for two hours more. He could have beaten Smith and both his seconds into the bargain, given fair play." "Was Slavin injured during the fight?" — "No; not from the blows of his rival, as he heeded them very little. He, however, received a nasty blow from a knuckle-duster by one of the cowardly ruffians, which caused his ear to bleed." "As to the referee's decision?" — "That official was undoubtedly afraid of his life, and thought it best to stop the proceedings before any serious harm happened." "What becamiof Smith after the fight." — "He returned to his hotel, and will no doubt arrive by a later train. His friends were disgusted with the form he displayed, and it will be a long time before he recovers his former prestige, if ever he does." "How did the Cornstalk behave in the ring?" — "He fought in the most manly style throughout, and gained the highest opinion from all respectable people present. A testimonial to Slavin has already been decided upon, and no efforts will be spared by those concerned in making it worthy of the occasion." Mr Ike White, a well-known sportsman in the city, and one who, as a rule, does not mind going to considerable trouble to witness a "mill," was very severe in his comments on the gang who were so lost to all sense of decency and fair play. Mr White said: — "The story of the fight does not need much telling. Slavin had his man beaten at every point, and was winning easily. Slavin is a very brave man. He had to go into Smith's corner every time, and when there had to fight not one but six men; the ruffianism was simply awful." [4, Col. 2c] "Do you think it was for the best that the contest was stopped as it was?" "Yes, certainly. Goodness knows what would have happened before long. Probably Slavin would have been killed, as the villains that had congregated in Smith's earner seemed determined, at all hazards, to prevent him from losing. More than once the Australian had Baldock on one side and Harper on the other, both jeering at him, whilst Smith was in front and the 'boys' were making all sorts of attempts to injure him, but he seemed to pay no attention to anyone but Smith. Slavin would not have had a mark from Smith, such as he does now having been inflicted entirely by the mob[.]" "What do you think of Slavin's abilities?" "He is a very great natural fighter, and as for his gameness a pluckier man never pulled off a shirt." On the subject of who was responsible for the presence of the rowdies that caused the bother Mr White was reticent, but not so when the subject of a testimonial to the Australian was mooted. "He is coming to town to-morrow," said the speaker, "and shall have a great reception. Some good sportsmen have promised to leave no stone unturned to give Slavin a testimonial to be proud of, for he richly deserves it." "What seemed the general opinion on the ground?" "Why every ''man'' (with great emphasis on this word) was sick and disgusted: all but the mob gradually forsook Smith's side of the ring, and the Englishman will lose many friends in consequence of the turn affairs took." </blockquote> ==== Reception of the News in Birmingham. ==== <blockquote>Considering the ''penchant'' of the natives of Birmingham for fighting, and their interest in all matters concerning the ring, a stranger in the city yesterday knowing this would have been rather taken by sur prise [sic] at the indifference manifested in the result. At the various local sporting resorts, however, the cause was plain enough to those in the know. Early in the week it was an open secret that a warm corner was being provided for the English Champion, consequently betting was at almost a standstill. In what little speculation took place the odds were in favour of Smith, as the ''cognoscenti'' were confident that the Australian would not be allowed to win. Amongst the better class of sportsmen in the city the whole of yesterday's disgraceful proceeding were viewed with the greatest disgust. There are still many staunch supporters of the ring in the district who would gladly hail any signs of its regaining its past glory, but they look upon the fight of yesterday as the death-blow to the institution. By the few that thought the affair might possibly be allowed to be decided on its merits Slavin was expected to win, but his only chance was considered to be in his forcing the fighting at the start [Col. 2c–3a] and knocking his man out early. George Prober hoped to hear that the fight had been decided fairly, and he regretted the unsatisfactory ending. How the Match Was Made On the evening of Saturday, August 10, the P. and O. steamship Carthage cast anchor in the Albert Dock, Limehouse. On bard was an individual, anxiously expected by the British public — namely, Frank P. Slavin, the Champion at Australia, who was accompanied by his manager, John Lewis. Without loss of time, Slavin made his way to T<small>HE</small> S<small>PORTSMAN</small> Office, and on the succeeding Monday the following interesting particulars respecting the visitor appeared in the columns of this paper:— "He has a long record, including victories with both gloves and knuckles, and has never yet known defeat. His bearing is that of a thorough gentleman. He is a fluent talker, and can converse on any sporting subject. Devoid of conceit, he yet has a full comprehension of his own powers, and speaks with confidence as to the result of any encounter in which he may take part. Slavin is a splendid representative of the nation which is growing up across the seas. The contour of his features is distinctly English, square cut and firm. Beneath an intellectual forehead are two deep-set piercing blue eyes, and his features are bronzed with the burning suns of the south. From this it will be gleaned that the Antipodean is a formidable-looking customer, especially when we add that he stands no less than 6ft 1in, and in condition fights about 13st 4lb. Long before his arrival 100''l.'' had been posted at T<small>HE</small> S<small>PORTSMAN</small> office for Slavin to box any man in England, but the money was waiting nearly four months before any of our big guns would cover it. Jem Smith, the Champion, turned a deaf ear to the straightforward offer of the Colonists, and Mitchell was called away to Yankeeland to lend assistance to his friend Kikrain [?]. For some time it looked as though our visitor would have to return as he came, without giving anyone a hiding or receiving one himself, until a gallant little English middle-weight stepped into the breach to box for the honour of the old country, and agreed to face the stalwart Cornstalk. This was none other than William Goode, who in consequence of his politeness, urbanity, and elegence of dress was christened by his friends 'Chesterfield.' Goode had previously lowered the colours of another Australian, Tom [Less?], a much bigger man than himself, and, bearing this in mind, his friends freely plunked down 200''l.'' These were Messrs Robert Abel and Harry Hart, two well-known figures in the world of sport, articles after little delay being signed at T<small>HE</small> S<small>PORTSMAN</small> office, whereby Slavin and Goode agreed to box the bout of twelve rounds, under the usual rules, on October 17, for the sum stated. Many old ring-goers and patrons of the games shook their heads when the articles were published, and not a few blamed 'Chesterfield' for his rashness in tackling at catch-weights a man so much his superior in size. Goode, however, comes of a fighting stock, is full of pluck and stamina, and belongs to the order which never say die. Excepting in a competition, his maiden attempt, 'Chesterfield' had never known defeat, and the making a match with such overwhelming odds against him his bravery received due acknowledgment on all hands. Slavin held an unbroken record of nineteen successes, and throughout his career he had never known the effects of a knock-down blow. The articles stipulated that the men should box in a 24ft ring, and at the time of signing Mr B. J. [Angle?] was agreed to by both sides as referee. A very necessary clause was inserted, giving the referee power to award the stakes in case of what he might deem an organised interruption to the man who, in his opinion, had the best of the boxing at the time, and if all agreements contain such a clause, it will have a deterrent effect on those who invariably go on the sin, tie, and wrangle system. Slavin placed himself under the charge of that painstaking trainer and old-time boxer, Jack Start. The pair made Mr J. Kilby's, the Ferry Hotel, Cookham-on-Thames, their head-quarters, but things went very badly at the start. During the second week of his training the Australian caught a severe cold, and rheumatism setting in, the services of a doctor were required. The illness was, for obvious reasons, kept a profound secret, but so bad did Slavin get that the first man of medicine deemed it necessary to call in a second. Ten days were spent in the house before Slavin pulled round, and though all went well for some time, he contracted another bad cold. Start, however, was unremitting in his attention to his charge, and Slavin came to the scratch in fairly good shape. The result of the encounter, a win for Slavin in the fifth round, despite a grand stand by Goode, will be fresh in the memory of our readers." [sic: quotation begins at the top of the paragraph] '''Smith's failure to make a match with the Australian''' caused general surprise, but the Englishman would have nothing to do with the glove business, despite the repeated offers of Slavin. The latter's friends, on the other hand, saw little but trouble attached to a knuckle fight, and though Slavin himself preferred the fists to the mittens, there appeared small chance of a match between the pair until Mr Frank Hinde stepped forward and put up a deposit of 50''l.'' at T<small>HE</small> S<small>PORTSMAN</small> office for the Australian to fight Smith for the championship and 200''l.'' a-side. The old question of stakeholder then cropped up, and, after a Iot of bickering, the Colonial gave way, and agreed that the money should be deposited with private gentleman, who for obvious reasons shall be nameless. A meeting took place, and eventually the following contract was drawn up by a representative of T<small>HE</small> S<small>PORTSMAN</small> and signed: Articles of Agreement entered into this day (Monday, September 16, 1889), between Frank Slavin, of Melbourne, Australia, and James Smith, of London, England. The said Frank Slavin and James Smith hereby agree to fight a fair stand-up fight according to the new rules of the London Prize Ring, by which the said Frank Slavin and the said James Smith hereby mutually agree to be bound. The said fight shall be for 200''l.'' a-side, open for 1000''l.'', lor the Championship of England and Australia, and shall take place in 1889 out of England. The two representatives to select the battle-ground issue all invitations (not exceeding fifty persons a-side), and carry out the arrangements for bringing off the fight. The backers of the said Frank Slavin and the said Jem Smith this day (Monday, September 16) deposit 200''l.'' with the stakeholder. The representative of each man to supply the other with a list containing names of spectators, and to have mutual power to strike out a name they object to. The said James Smith and the said Frank Slavin each to have power to appoint an umpire. The referee to be mutually agreed upon by the duly authorised umpires of the men at least seven days before the day fixed for the fight, but in case they cannot agree, the final stakeholder to have power to appoint a referee. The men to be in the ring between the hours of six a.m. and twelve noon, or the man absent to forfeit the battle money. The expense of the ropes and stakes shall be borne by the two contestants equally. In case of magisterial interference the referee, if appointed, or the stakeholder if not, shall (if possible on the same day) name the next time and place of meeting, and either party failing to appear at the time and place specified to lose the battle money. The stakes not to be given up unless by mutual consent, or until fairly lost by a fight, and due notice shall be given to both parties of the time and place of giving up the money. In the event of any question arising which may not be provided for in these articles the referee to have full power and authority to decide such question, his decision to be final, conclusive, and subject to no appeal in any court of law. The stakeholder shall in any and every case be exonerated from all responsibility upon obeying the direction of the referee. In pursuance of this agreement we hereunto subscribe our names. [4, Col. 3c] Frank Hinde (for Frank Slavin). John Fleming (for James Smith). Witness for Smith, F. Montague. Witness for Stavin, John Lewes. Subsequently Slavin, as stated, defeated Goode, following which he fulfilled an engagement at the Royal Aquarium extending over thirteen nights. The "Cornstalk," though suffering from an injury to his left hand, offered 20''l.'' each evening to any man whom he could not step in four thee-minute rounds, and though several tried to earn the money Slavin always accomplished his self-imposed task, and brought his engagement to a close in a blaze of triuumph by stopping two men the last evening in four rounds. Slavin had now come into funds. Through the columns of this paper he expressed a wish to put some of his own money down, and, confident in his ability to uphold the honour of Australia, he offered to increase the stakes to 500''l.'' a-side. Smith, with a millionaire at his back, had little difficulty in getting the extra 300''l.'', and accordingly the money was made 1000''l.'', the sum fought for by Sullivan and Mitchell. Smith in the meantime, though ignoring Slavin's challenge to box under Queensberry rules, strange to say, entered into an engagement with Jackson under the conditions he so stoutly objected to when put forward by the white man[,] His ignominious show with the coloured Champion may be passed over without comment, and it will suffice to say that after he and his conqueror had boxed together for ten nights at the Aquarium the Englishman began to prepare himself for the affair under notice. </blockquote> ==== The Men in Training ==== <blockquote>Slavin, when he entered upon his training at the Nayland Rock Hotel, Margate, was 12st 9lb in weight, while fourteen days later, in the buff, he scaled 13st 6lb, and was as hard as nails. The increased weight was accounted for by the splendid development of the muscles in the arms, shoulders, and back. His daily programme while at Margate was as follows:— Up at seven sharp, and twenty to twenty-five minutes' strong exercise with 4lb dumb-bells, followed by a gentle stroll of a couple of miles before breakfast, at 8.30, which consisted of porridge, 1lb of chops or steak, dry toast, and a cup of tea. After the perusal of the morning papers he indulges in a ten-mile walk at a smart pace, averaging five miles per hour. Back again to the hotel, into a bath, and then a rub down with whisky, which was completed in time to give him a good rest before dinner, timed for 1.30, and composed of either roast beef, mutton, or chicken, with vegetables, light pudding, and a pint of seven-year-old bitter. The meal being digested over a game of billiards, he started at three o'clock on a six-mile stroll, varied at intervals by sprints of one hundred yards. On his return to his quarters he punched the ball for half an hour, and then sparred lightly with an Australian gentleman who was at the time on a visit to this country, and holds the Amateur Championship of Australia, he having kindly consented to assist Slavin. This was followed by a sponge and rub down and a good slapping of the muscles before a tea, at 6.30 p.m„ [sic] of cold meat, half a dozen eggs, dry toast, and tea. The wind-up of the day was a quiet stroll to the pier and back, and a game of billiards before retiring to rest, at ten o'clock sharp. Smith's programme was something of the same description, excepting the ball punching, the Englishman preferring the sack. He made the Greyhound,  Newmarket his head-quarters, most of his exercise being taken on the Heath, though, as visitors were forbidden and interviewing tabooed, little was gained [Col. 3c–4a] as to his doings. Under the care of Jem Howes, his old trainer, he was, however, reported to be doing well, and much finer than when he fought Jackson. </blockquote> ==== Finding the Battle-Ground. ==== <blockquote>(By one of the Explorers.) At a meeting held on Saturday, November 16, Mr John Fleming and Mr G. T. Dunning were deputed to act on behalf of Smith and Slavin respectively, their duties being to select the battle-ground, issue invitations, and carry out the arrangements for bringing off the fight. This was rather a strong order, and one of a most trying nature, as anyone conversant with the peculiarities of those attached to the P.R. may know. Wednesday, December 4, was a cold, raw day, and with the thermometer down to freezing-point travelling at night was anything but a luxury. Reaching Paddington soon after 9 p.m., Mr Fleming and I, thanks to an energetic guard, soon found ourselves comfortable in a first-class "smoker" attached to the Weymouth express. At 9.15 to the tick we steamed away from the Great Western terminus, and in due time reached Reading. The hour had passed quickly, pleasantly whiled away by interesting tales of old-time bouts told by the manager of the Pelican boxing. Such men as Punch Dowsett and Bill Charlton graduated in Mr Fleming's school, and the way these celebrities used to set about each other for as many shillings as the boxer of to-day gets pounds is nothing less than remarkable. A ten minutes' halt at Swindon was utilised to the fullest extent, and then bowling along we reached the end of our journey, so far as land was concerned, soon after 2 a.m. on Thursday. When we left town the air was crisp and frosty, with hardly a breath of wind stirring. We were, therefore, greatly surprised when stepping on beard the Gazelle we were informed that a "choppy sea" was running outside. The fact of a passenger's hat going over the side proved the truth of the assertion, and then this same passenger, a likely-looking fellow, bemoaned his fate and bad luck. "How confoundedly annoying,"  he said. "This is the sixth time I have been across during the year, and not once has it been calm." "Better have a sleeping berth, sir," said a sprightly youth at the top of the stairs. "Sleeping berth be hanged. I'll remain on deck," said he, and here for a time we left him inquiring if his horses had gone across in the morning. Guernsey, dear reader, was our destination, and with the idea of making ourselves comfortable we made for below. I felt a bit "peckish" and cast a longing eye on the good things set out in the dining saloon. This was, however, as far as I went in the line, and diving a floor lower doffed my boots and courted the god of sleep. Morpheus, however, scorned my attentions, thanks to the clatter on deck and the noise of the machinery, to say nothing of the "magging" [?] of our friend of the horses. This gentleman, after three or four futile attempts to drag me into a controversy about traveling, "struck ile [?]" with an elderly party, occupying the berth behind me, and for nearly an hour I had a pretty lively time of it. The "elderly party" had a voice greatly resembling the dividing of tin hoops with a file, and in addition displayed a shocking habit of making horrid and atrocious puns. Just as I thought of giving up sleep for a bad job a gale sprang up. Though the Geselle is a record breaker she soon felt the effects of the breeze and began to roll heavily. The increase in the motion of the steamer was followed by a decrease in the conversation around me, and by degrees the punster went from had to worse. The "[hussey??]" [one?] also dropped into a walk, and after monosyllables had been exchanged the two came to a dead stop. Offering up a prayer of thanksgiving for this I closed my eyes again, and being a good sailor was quickly sleeping the peace of, I hope, the just. The concussion of the Gazelle against the Guernsey Pier, accompanied by a prod from Fleming's stick, at length aroused me. [4, Col. 4b] Among the Channel Islands. The time by "Joe Vickers" was 7 a.m., and half-awake I took to my boots. "Need not lace them; we shall be there in a minute," said Fleming, and in a drowsy, submissive, take-me-anywhere-if-only-to-bed sort of way I followed him on deck. A Babel of voices and a clutch at my bag and rug thoroughly aroused me, and jumping into a trap the Pelican and I were in about three minutes set down at Gardner's Royal Hotel. A venerable-looking elder, whom Fleming voted a "[sheenie?]" (goodness knows what he meant, though), made us welcome, and agitating the communicator he handed us over to the care of a dark-eyed chambermaid. I forget her name, and as Fleming is not here I cannot give it. I will say no more than that after a cup of tea diluted with delicious cream, we took a well-earned and mucch needed rest. Up and doing soon after tea, a delicate task was before us. Fleming had a friend on the land, a gallant captain, who knew of a spot where we could fight for a month. Guernsey, dear to the "holiday maker" and the "honeymooner," is, as everybody knows, or should know, situate in the English Channel near the coasts of Brittany and Normandy. It is 68 [?] miles from Weymouth, 7 from Sark, 19 from Alderney [?], and 25 from Jersey. I mention these distances, for we explored the whole group. Encompassed with rocks, almost hidden in high water, navigation is exceedingly dangerous at all times near the island, the knowledge of which quickly knocked one of our plans on the head. Standing at the door of Gardner's Royal Hotel on Thursday morning Castle Coronet came in view, while in the distance, almost hidden by a heavy sea mist, could just be discerned the islands of Herm [?], Jethon, and Sark. Guernsey, it should be mentioned, though under the protection of England, boasts a sort of Home Rule government, rather irksome to the stranger within its gates, especially if that stranger is on mischief bent and gets caught. Making, in a cautious manner, inquiries at the breakfast table, we found a friend in "Mike." Said I, "He's a Frenchman." "Get out," replied Fleming, "he's a 'bark.'" "Drinks he isn't," "Done; drinks he is." "Mike" had not at that time spoken, but had noiselessly passed to and fro with a military step and a hand behind him. In reply to a call from Fleming he approached, and a "Yes, yer honour," told me I should have to "part." "Mike" was a trump, and I loved him from the start. For eleven years he had been in the service of a colonel at 1''l.'' a week, and three suit of clothes in the year. Hotel pay was not so good, and though he made "a bit" in the summer, the young ones were generally there when the bills were paid, if not when the work was on. "Mike" told us lots of things in what many consider the "fascinating brogue." He informed us — and how our hearts beat at the news — that the island, which had a population of over 32,000, employed but six policemen. "There's not a beggar in the land," said Mike, "and but one Hansom cab, and," pointing to the window, "be jabers, there it goes. " So far so good, but after a walk round the son of Erin gave us a shock by saying, in reply to a query from Fleming, "They've a way of their own on this island, and nearly ivery [sic] other man is a special constable." Fortunately we had just finished our repast, and, supporting each other, we tottered faintly to the door, partially regaining strength with a breath of the pure sea breeze. Beads of perspiration stood on the brow of the Pelican, whilst I was suffering from a "trickling" down the back of anything but a pleasing nature. Visions of a dungeon-cell under Castle Coronet flashed through my brain as a voice and a step were heard behind, and then I was somewhat reassured. "When would you like a chair?" fell softly on mine ear. Afraid that we had been thought of as a bit week on the leg, I turned to the speaker and asked what he meant. Explanations ensuing, we found the "chair" was a sort of Bath chair on wheels used throughout the island. Declining the offer, we took a stroll, and putting this and that together, came to the conclusion that our task was of a very delicate nature. The first thing was to interview the captain, who, in reply to a note, courteously waited upon us. He gave us the geography of the island and an introduction to Mr M., a friend, who we unfortunately found away from home. Taking a "chair" we then started on a voyage of exploration, making, as advised, our way to L'Ancresse [?] Common. Leaving St. Peter's Port and passing through St. Sampson's — the Vale — we came across acres of vineyards, in one instance extending nearly a mile along the road-side. Half an hour's drive brought us to the common mentioned, and dismounting we tried in vain to find a level piece of turf. Windmills abounded on all sides, and plodding on we reached L'Ancresse Bay, a lovely little spot, where the sea rippled softly over a bed of almost snow-white sand. Nowhere could be found a suitable spot whereon to pitch the "magic square," and as the shades of night were falling fast we rattled back to the "Royal." A wet night offered no inducement for further travel, and it was a case of early to bed and early to rise, the next day finding Fleming and myself at the door of Mr M. Acquainting this gentleman with the Nature of the business in hand he, like a good sportsman, fell into the scheme and at once volunteered to drive us to "the best spot in the world." "Bessie" was harnessed to the village cart, and away we went at the rate of fully fourteen miles an hour in the direction of the Forest. I have sat behind many a good goer, but must for her size award the palm to Bessie a beauty barely twelve hands high. Throwing the reins in the bottom of the vehicle, Mr M. let the pony have her head, and the way she went uphill, down dale, and past other traps was truly astonishing. Great St. Peter's was passed, and lovely scenery encountered, the gardens being full of flowers, geraniums and roses blooming on all sides. An enjoyable drive of forty-five minutes found us at Boequaire [?] Bay, and directly in front stood the island of Lihou. As many of our readers may know, Lihou is a small hill of land that at low water can be reached on foot from Guernsey. As a fact, a paved roadway is laid in the bed of the ocean, across which both foot passengers and carts easily make their way. With the tide up communication is effected by boats, but this being low at the time we had the novel experience of Driving Through the Sea. Gaining the other side we "explored" and as the piece of land is only some three hundred yards by a hundred and fifty, we were not long about it. Two excellent patches of level turf were found, but just as we were making for the trap a gaunt, Robinson Crusoe-looking individual scaled one of the small stone walls and barred the way. Of course, he wanted to know our business, and, after a rather rough opening, quickly "listened to reason." In the course of conversation we found that the population of the island was limited to three, the old "josser" and his two daughters, with a "moke" thrown in. Pointing a long skinny finger, which might have belonged to the Witch of Endor, towards the quadruped mentioned, the old man said, "Us two keeps the family. He draws the seaweed and I burn it."  "And why do you burn it?" "Well, to make [Col. 4c–5a] ashes, and from the ashes iodine is manufactured." "And how much do yen earn a week by that?" said  I. "Oh, about 4''s.''; not 5''s.'' any week." Great Scott! and this was all the old man, his two daughters,  and the "moke" had to live on. Handing him a franc each, which nearly stupefied the old chappie, Fleming and myself returned to Mr M., who drove us rapidly back to St. Peter's Port. The next day we crossed to Sark and Jersey, but found nothing so suitable as the ground at Lihou, and fairly well satisfied with the result of our visit, a day later boarded the Lynx for the return journey. During our visit the weather had been of a fairly favourable description, but the voyage home was made under very depressing circumstances. Rain fell heavily and a thick mist hung over the water, which after going a few miles was alive with porpoise. Some of these animals came within a few yards of the Lynx, but the speed of the boat proved too good for the finney ones, who were eventually left behind. With a breeze springing up sail was hoisted, and dashing through a heavy sea in splendid form the Lynx made some sixteen knots in the hour. In this way half the journey was completed, when all of a sudden we were caught in a squall. In an instant the wind chopped round, and before you could say "Jack Robinson" the good vessel was turned broadside to. The order to take in sail was promptly obeyed, but the clatter on deck brought many an anxious passenger rapidly from below. A very heavy sea was now running, and though the Lynx kept her course bravely the decks were swept from stem to stern. A huge East India-man now hove in sight, and, as one of the men informed me, she had the audacity to cross our bows instead of passing under our stern. This breach of ocean etiquette ruffled the skipper of the Lynx, who chased the trader, and eventually made her alter her course. This little "diversion" caused much amusement amongst our passengers, and after a cold, rough passage we landed safely at Weymouth. Chilled to the bone, we made for the Victoria Hotel, where a chop and a glass of old October revived the almost stagnant circulation. London was reached about 9.30, and, tired and worn out, I was glad to lay my head on a pillow I had not seen for four days. From London to Ostend. Unforseen [sic] difficulties having cropped up, the Channel Island scheme had to be abandoned; consequently we were once more called upon to leave our native land. This time Belgium was our destination, and having carefully studied the map of that country, we took our departure one fine starlight evening from Charing-cross by the 8.15 Continental express. In the previous week we had the luxury of a compartment to ourselves, but on the occasion under notice we were not so fortunate. Two individuals, one with a strong Midland accent, and the other a Frenchman speaking bad English, shared the carriage with us, and at such a rate did the former's tongue go directly he entered that I gave up reading as a bad job, with a sigh put away my unfinished book of the previous trip. Fleming fared better, and having a knack of ignoring all around him, once more tackled "Blood Money," and almost read himself off to sleep.  In the meantime our friends in the opposite corner made "hay," and I soon found out they were both in the lace trade. With a tongue that went a couple of hundred to the minute, the Midlander almost monopolised the conversation, from which I gleaned the two were bound for Calais, and thanked goodness we should part at Dover. Reaching this port about ten we boarded the Ostend boat, which, as regards passengers, was very poorly patronised. Hardly a breath of wind was stirring, and with the sea calm as a mill-pond we had a pleasant passage over, and landed safely at Ostend soon after 3 a.m. A cup of coffee was hastily swallowed, and a half-hour's run in the Brussels express found us [4, Col. 5b] At Bruges. Leaving the train, we had considerable difficulty in finding our way out of the station. For a moment we caught sight of a drowsy old porter, but the last carriage had not passed away from the platform ere he was lost to view. Seeing an opening on other side we made for it, only to have our passage barred by a half-dressed Belgian who, whilst displaying a total ignorance of English, Irish, and Scotch, directed us to return the way we came. For some time we tried in vain to find an outlet, and just as I had made up my mind to walk the platform until daylight Fleming found an iron gate ajar. Without loss of time we were in the street, and crossing the round, knocked loudly at the door of the nearest hotel. All was in darkness, and with no response to our fourth appeal for admittance, a return to the station or a "tramp round" appeared to be our only alternative. A slight noise inside followed by a shuffling of feet, again raised hope within us, and when, after some trouble, the door swung back and brough to view a shock-headed Belgian our relief was great. No time, I can assure you, was lost in getting between the sheets, and rising betimes we again went on a voyage of discovery. Fleming had a chum in the town, and to his house of call our steps were directed. Again disappointment was in store for our wanderers, and a feeling of disappointment came over me when we found Mr G. was away. There was, under the circumstances, nothing left but to wait, and Fleming, who puts on hair rapidly, decided to place himself under the care of the town barber, or, I should, properly speaking, my ''coiffeur''. For this piece of indiscretion he had to come away minus a slice of his lower lip, which, fortunately, was not large enough to seriously reduce his avordupois [sic?], and heaping blessings (?) [sic] on mankind generally, not in any way forgetting the "Bruges Barber, we roamed over the old town, noted for its magnificent cathedral and many seats of learning. The hours sped on pleasantly enough, and in due time our friend was unearthed. Being pledged to secrecy I am not going from my word by giving full particulars of The Battle Ground placed at our disposal. This is in close proximity to the town — in fact, not half an hour's walk, and on reaching the spot we were shown a lovely piece of turn. A clump of trees on each side partly hid the house from view, and when I say that the ring was to be pitched on a lawn tennis ground, it will be seen that neither side could claim an advantage as regards standing ground, &c., the lawn being as level as a billiard table. Though our efforts so far had been crowned with success, we did not get permission to use the "pictch" without much trouble. The matter had to be seriously considered, and Mr G. would not give a decided answer without waiting another day. Consequently our stay had to be extended and the following morning, after repeated promises that the affair should be conducted in an orderly manner with not a rough at the ring-side, we got the answer, "Yes." "But," said Mr G., "if there is any row or crowd I can assure you you will have a journey for nothing; therefore if trouble is at all probable keep away and save your money and time." As long as faith was not broken by either side we saw no reason why the matter should not be settled in a proper manner, and making all the necessary arrangements and laying down plans of a most complete description, we returned to town well satisfied with the result of a visit to Bruges. [4, Col. 5c] Trouble about the Referee. On returning to town we received satisfactory reports of the work done by each of the contestants. Slavin, looked after by Josh Cosnett, the Birmingham heavy-weight, and his friend Mr Michael Taylor, of Australia, though rather light, was in good health. At one time he scaled only 12st 8lb, but a judicious spell of light work brought him back to 13st odd. Considering the importance of the business in hand, and its bearing on future events, Slavin had some  cause for anxiety. In addition to this he was fighting for 300''l.'' of his own money, and consequently wished to do himself justice in the international battle. The next question was the selection of someone capable and willing to fill the all-important post of referee. According to the articles it was left to the stakeholder to appoint the official named providing the representatives failed to agree, and in the end this course had to be adopted, solely owing to the objections lodged by Smith. The first gentleman suggested by Slavin's side was Mr B. J. Angle, whom Smith promptly objected to. Next a well-known owner of racehorses (a gentleman who adjudicated upon the knuckle fight between George Camp and "Click" Soles) was proposed with no better result. Mr Bat Murphy, strange to say, would not suit, and then in succession "No" was said to the names of  Messrs G. H. Vise, A. F. Bettinson, and [B.?] Bayley. All these gentlemen, it must be stated, were proposed by Slavin and objected to by Smith, who in the meantime had named a member of the Pelican Club, a gentleman of limited experience in these matters, and the landlord of the house from which he was training, Mr W. Riley, Newmarket. This brought about a deadlock, and the state of affairs getting wind, ugly rumours were soon afloat, and even money, and in many cases good odds, were betted that there would be "no fight." All this while Slavin was chafing and fuming at the delay, whilst at the same time his  representative and Smith's were at work almost night and day endeavouring to bring about a settlement of the difficulty. For a long time it looked as though the matter would end in smoke, as after the services of the stakeholder had been called upon great difficulty was experienced in getting anyone to accept the office of referee. So late as Friday at noon nothing had been done, and it was not until the evening of that day that Mr Joe Vesey, consenting to stand, was nominated by the stakeholder. A Scare. Though the battle-ground was only known to two persons, the country where the fight was to be decided being, in fact, or supposed to be, a perfect secret, on Friday morning a paragraph said to have been sent out by a news agency appeared in several papers, and created intense astonishment and consternation. This, set out in large type by those who we should have thought would have suppressed the account, stated that Smith on the previous evening had arrived in London from his training quarters, and even went so far as to name the street he slept in. That Smith's visit to town was extremely injudicious there is not the slightest doubt, but this was not the worst. The time of departure for the scene of action was given, with a description of the place selected. This publicity had the effect of keeping away many who bad expressed a wish to be present, and on Slavin's side no less than eight gentlemen, each holding a high position in the sporting world, declined to have anything further to do with the affair. Who divulged the secret is at present a mystery, but there is not the slightest doubt that the information so freely put forward not only opened the eyes of the authorities, but gave the "mob," to a certain extent, a key to the [Col. 5c–6a] situation. Slavin received the news with no small amount of astonishment, and a couple of telegrams informing him that a batch of the "boys" had gone across to make things warm for him did not give peace to his troubled mind. Smith made his way out of England on Friday by the short sea route, Dover to Calais, which he reached in safety. Slavin, not so fortunate, was arrested on Satuday, as already reported, but, after being bound over to keep the peace, he got away the same evening.</blockquote> ==== Performance of the Men. ==== <blockquote>Jem Smith was born in Whitecross-street, in the parish of Cripple-gate, on January 21, 1863. He stands 5ft 8¹/₂in high, and weighs in condition 12st 10lb. Round the chest he measures 43¹/_?in; waist, 36¹/₂in; hips, 41in; thigh, 24¹/₂in; calf, 16¹/₄in; biceps, 15¹/₂in. For some years he was employed in one of the metropolitan timber yards, but developing a taste for boxing, after one or two rough-and-tumbles with his mates he was taken in hand by Jack Knifton ("81-tonner"), and later by Mr F. Grimm, of the Central Club. Smith has never been defeated, though in his first engagement he did not shape like a coming Champion. His first success was in a competition at the Griffin, Shoreditch. Later he beat Snowey, of Holloway, and was then matched to box Harry Arnold, with gloves, for a 10''l.'' purse. Arnold, though a stone and a half lighter than Smith, stripped in good condition, having for some time previously been engaged in training Jack Massey for an important engagement. The affair was looked upon as a good thing for Smith, but it took him nearly an hour to polish off the Seven Dials' representative, though he had slightly the best of the encounter from start to finish. Subsequently the veteran Goode deposited a [sov?] on behalf of Smith to match him to fight Massey, but this was forfeited. Smith's next engagement was with Woolf Bendoff to box to a finish with gloves for 25''l.'' a-side, which came off at an East-end club. In this contest Smith injured his right arm, but, nevertheless, proved successful at the end twelve rounds. Smith also won Tom Symonds's All-comers' Competition on February 26[?], 1885, at Bill Richardson's, defeating Sugar Goodson, Jack Wannop (the wrestler), and Tom Longer. At the close Smith was presented with a large oil painting of himself, executed by a prominent patron of the sport. Smith's next battle was with Jack Davis for 100''l.'' a-side and the Championship, on the turf, and came off on the borders of Surrey and Sussex, on Wednesday, December 17. In all six rounds were fought, occupying 7min 56sec, Davis being knocked out of time with a swinging right-hander. He subsequently met Alf Greenfield, of Birmingham, for 300''l.'' at Maisonne-Lafitte, near Paris, on Tuesday, February 16, 1886 [?]. Thirteen rounds were fought, mostly in Smith's favour, and the men fell, whereupon a cry of foul was raised by Greenfield's party, and a crowd of roughs broke into the ring, stopping the fight. The referee (Jem Mace), at the request of the principal backers of the men, agreed to decide the battle a draw. Soon after Smith was matched to fight Jack Knifton, the "81-tonner," as he is called. This proved a ''fiasco'', a two days' dreary tramp on the Continent being followed by a return to the old country. Knifton's people claimed that Smith had more than the specified number of followers, but there is little doubt that only one side wanted a fight, and that was not the "81-tonner's" lot. Meeting after meeting was held, Smith offering to fight anywhere the other liked, and after much wrangling arrangements were made to bring the affair off near Oxted [?]. Somehow of other the police got wind of it, and overtaking the Knifton party near Croydon rendered another postponement necessary. this time the arrangements were left in the hands of Knifton's side, with the result that the principals, seconds, and a dozen others were captured early one morning in a furniture van by the police before they had gone fifty yards as their journey. All were brought up at Thames Police-court, and after a remand bound over to keep the peace for twelve months. The memorial struggle between Smith and Kilrain, brought off on an island in the Seine, came next, darkness putting an end to the affair, which also resulted in a draw, after the men had faced each other for 106 rounds, on December 19, 1887 [?]. Jem's recent performance was a Ten-round Glove Contest with Jack Wannop, the Champion laying 250''l.'' to 200''l.,'' and winning easily, following which he was beaten in two rounds at the Pelican Club by Peter Jackson, the Coloured Champion, in a glove contest, for 1000''l.'' [4, Col. 6b] Frank P. Slavin. the Champion of Australia, was born on January 27, 1863, at Maitland, N.S.W. He stands 6ft 1in in his stockings, and in condition scales 13st 5lb or 13st 6lb. Slavin served his time or apprenticeship to a coachbuilder and blacksmith, and first came out as a pedestrian. He always had a liking for the gloves, and sparred a great deal when young, but did not enter into any match until the latter part of 1885 — that is, for money, though he won several competitions previously as an amateur. Slavin's first fight was with knuckles against M. Power for 50''l.'' a-side, and he won after seven rounds, lasting thirteen minutes. He then beat Jem Burke with 2oz gloves for 200''l.'' a-side and the Championship of Queensland, winning in three rounds. This was in December, 1885 [?], and in the following year the Australian formed a combination and went touring, offering purses ranging from 10''l.'' to 20''l.'' to any man who stood up for four rounds. At this game Slavin had an easy time of it; some stood one round, and some two, but none of them four. Towards the end of the year he went to Sydney, and entered into an agreement with Larry Foley, who has a big place there. Here Slavin met Taylor, a pupil of Jackson, for a purse with small gloves, and stopped him in two rounds. He was then matched with a big fellow named Bligh for 10''l.'' a-side, and beat him in one round. After a rest of two months articles were signed for him and Mike Dooley to box for 100''l.'' a-side. Dooley had a big reputation, but Slavin won in nine rounds. The subject of these remarks then had a little difficulty in finding an opponent, but eventually Mike Costello, an American, a good man, made his appearance, and the pair were matched for 100''l.'' a-side. They had a big battle in Sydney, lasting two hours and a half, and a draw was the result. Another match was made for 400''l.'', and 50''l.'' a-side was posted, but Costello forfeited this. Afterwards Slavin's backers matched him for 24''l.'' a-side to stop Costello in six rounds, but the latter is a very clever and tricky man, and lasted the time. Subsequently Frank journeyed to Sydney, and finding Mike there, challenged him again. The result of this was a match for 100''l.'' a=side with skin gloves, which Slavin won in twenty minutes. Slavin at this time had any amount of backing, and issued a challenge to fight Peter Jackson for 250''l'' a-side and the Championship. Jackson's party wanted a match with gloves for a purse. They could not come to terms, though Slavin's backers offered Jackson 50''l.'' to sign articles for 500''l.'' Australian was now a bit bare, so in January last year the Australian made a trip to New Zealand. The first man put up was Snath, who was backed to stand four rounds, but he had had enough at the end of the first. In Dunedin Slavin beat a big fellow in four minutes, and journeyed a long distance to fight Laing, the Champion. Terms could not be agreed upon until they had "fiddled" Slavin for nearly six weeks. The pair were then matched for 200''l.'' a-side, and fought with 2oz gloves at [Wangazul?], Laing failing to come up at the end of the fifth round. After this Slavin went back to Melbourne, hoping to get on a match with Jackson, and was surprised to find he had gone to America. Following this he met Jack Burke, but after Slavin had had all the best of it the contest was declared a draw. Mike Dooley was now in Sydney, and issued a challenge to him. This led to a match for 200''l.'' with small gloves, which ended in Mike being knocked out in 2min 40sec. He was very bad, and frightened all by not coming to for nearly half an hour. Slavin returned to Melbourne, and Burke having put several challenges in the paper, our visitor offered to stop him in six rounds; 200''l.'' a-side was put up and articles signed for 4oz gloves, but on the night Burke's party threw down regular pillow-cases. Of course this did not suit the other side, and there was a fine old wrangle, lasting two hours and a half. Eventually Mr Joe Thompson, who was referee, declared all bets off, and the two fought 6oz gloves, and agreed to divide the gate, and Burke was beaten in the middle of the third round. Previous to this Billy Farnan, the conqueror of Jackson, and Slavin, fought for 200''l.'', with the result that the latter added another winning bracket to his name, Farnan failing to answer to the call of time in the third round. This is considered to be one of Slavin's best performances. About this time Woolf Bendoff, of Whitechapel, was in Melbourne, and finding plenty of backers, they put up a forfeit of 100''l.'' for the Londoner to box Slavin, for 500''l.'' a-side. After seeing the latter polish off Burke, however, Bendoff's friends would go no further with the atch, and Slavin accordingly pocketed the "century." An easy victory over Bill Buck in two rounds followed, and then Slavin, on October 17 made his first appearance in England at Astley's Theatre, where he beat "Chesterfield" Goode in five rounds in a match of twelve rounds, for 400''l.'' [4, Col. 6c] </blockquote> ==== THE PELICAN CLUB AND THE FIGHT. ==== <blockquote>To the Editor of the Sportsman. Sir, — As an impression prevails that the Smith and Slavin fight was arranged under the patronage of this club, I should esteem it a favour if you would allow me to state emphatically that the Pelican Club gave no countenance to the affair in any way whatever, and had nothing to do with it. — Yours truly, Cecil Raleigh, Hon. Sec. Pelican Club, 21, Denman-street, W., Dec. 23. __________ We hear on good authority that it is the intention of the members of the Pelican Club to present Slavin, the Australian Champion, with a belt, in recognition of the manly exhibition he gave yesterday at Bruges. </blockquote> ==== THE CHAMPIONSHIP OF THE WORLD. ==== <blockquote>Frank Slavin to John L. Sullivan. Frank Slavin, the Champion of Australia, is prepared to meet John L. Sullivan, under London Prize Ring Rules, for 500''l.'' or 1000''l.'' a-side and the Championship of the World. Slavin has lodged with us a sum of 100''l.'', and will contest the title with Sullivan in either America or Australia in six months from signing articles. We have cabled this challenge to Mr R. K. Fox, of New York, and the money lodged with him or the Editor of T<small>HE</small> S<small>PORTSMAN</small> will lead to a match.<ref name=":1" /> </blockquote> === Dundee ''Evening Telegraph'' === This Wednesday, 25 December 1889 article describes Slavin's reception in London after the fight. Viscount Mandeville was there, suggesting that he was a Slavin supporter:<blockquote>There was (says a sporting correspondent) great excitement in London yesterday over the fight of Monday, and all classes of the community expressed their abhorrence of the proceedings adopted by the Smith party. It was known early that Slavin would journey up from his quarters at Margate about mid-day, and by two o'clock there was a large gathering in and about the Holborn Viaduct Station. By three o'clock the crowd had increased enormously. The train arrived behind time. As soon as Slavin and Mr Taylor were recognised, a loud cheer was raised. So great was the crush that it was only with the greatest difficulty that the Australians could make their way to the street. The reception accorded the champion, although very gratifying, was somewhat rough, Slavin and his party being forced across the road before they could take refuge in a hansom. Among those present were John Lewis, Slavin's manager; [[Social Victorians/People/Mandeville|Lord Mandeville]], E. Bayley, and other well-known sportsmen. From the station Slavin went, in answer to an urgent request, to the Stock Exchange, where another enthusiastic reception waited him. A move was then made to the office of the ''Sportsman'' in Fleet Street. Among those who were present to offer their sympathy and congratulations to Slavin on what all considered to be a victory were [[Social Victorians/People/Mandeville|Lord Mandeville]], Ike White, E. Bayley, George Knight, W. Riley, C. Mitchell, J. Goldberg, J. Kilby, F. Symes, F. Hinde, and a score of well-known boxers. Shouts for Slavin were kept up outside, and the crowd could not be silenced until Slavin went to the window. He bowed his acknowledgments, and after much difficulty obtained a hearing. He thanked the multitude for his great reception, at which three cheers wore raised for him, and a corresponding number of groans for Smith. Later Slavin dined at the Albert Club where a Testimonial Committee was formed. At seven o'clock Slavin departed for Margate. Smith remained in Bruges until one o'clock on Monday, when, in company with Baldock and Harper he left for London ''via'' Calais. They arrived in London at eleven o'clock, Smith going home in company with a friend. Smith has a wound over the right eye, and his face is much swollen.<ref>"London Gives the Colonist a Great Reception." ''Dundee Evening Telegraph'' 25 December 1889, Wednesday: 3 [of 4], Col. 6b [of 8]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000453%2F18891225&page=3&article=052&stringtohighlight=mandeville+viscount. Print title: ''TheEvening Telegraph'', n.p.</ref></blockquote> === ''Reynolds's Newspaper'' === The Sunday, 29 December 1899, of ''Reynolds's Newspaper'' published a detailed account of the fight.<blockquote>The fight between Slavin and Smith took place on Monday morning upon private property in the outskirts of Bruges. Various spots, both at home and abroad, were from time to time named as the possible battle-field, but finally it became known to a certain select few that an English gentleman, Mr. Atkinson-Grimshaw, residing near Bruges, had placed his grounds at the disposal of the combatants. The host is a well-known breeder of fowls; and he certainly did not expect the quality of fighting cock which responded to his invitation. The ground was encircled by large trees, which secured the utmost privacy. About forty persons assembled at the ring-side, including Viscount Royston, Viscount Mandeville, Mr. Abington, Mr. Harris, Mr. W. Riley, Mr. P. Kotchie, Mr. Ike White, the Hon. M. Sandys, Mr E. Bayley, Mr. C. Parsons, Mr. J. Kilby, Mr. C. Morton, and other well-known "sports." Smith was dressed first, and had to wait a few minutes for Slavin. The Englishman appeared in white flannel drawers, white socks, and lace-up boots; while the Australian wore black drawers, blue socks, and lace-up boots. Harper and Baldock were seconds, Howes bottle holder, and Mr. Fleming umpire for Smith; Cosnett and Bob Kirby, Mr. Taylor, and Mr. W. Riley acting in similar capacities for Slavin. Mr. Joe Vesey officiated as referee and Mr. Calder as time-keeper. The men were in the ring at 8.25, and ten minutes later the fight began. After the first two rounds everything went in favour of Slavin, who in the third round knocked Smith clean off his legs with a terrific right-hander. He repeated this operation four or five times subsequently and surprised many of the spectators by the determined way in which he fought. In the thirteenth round he doubled Smith up with a fearful blow under the left ribs, and the Englishman's friends, seeing that Smith was almost beaten, raised a cry of "Police!" Smith was hurried from the ring; but Slavin and his friends refused to budge, and, after "Time" had been called, they claimed the fight. The referee, who appeared afraid to give a just decision, was surrounded by partisans of Smith, who had meanwhile come back, and eventually ordered the fight to proceed. Prior to this Slavin had been repeatedly kicked on the legs and hit on the body and head with sticks and knuckle-dusters. These gross and cowardly outrages were committed in Smith's corner, where all the fighting took place from start to finish. The next round, the fourteenth, was the last. Slavin fought in a most determined fashion, and when he was punishing Smith heavily, the latter caught the Australian round the waist and held him on to the ropes, whilst the ruffians standing around beat and kicked him in a most cowardly fashion. Amid cries of foul, the pair fell to the ground, and, on the men taking their corners, the referee said he would act no longer, as it was perfectly clear Slavin was not to have fair play. This created immense excitement, during which the referee declared the light a draw, and, crossing to Slavin, said, "I do not want to stay here to see you killed." Afterwards the roughs tried to get at Slavin, who, however, managed to hide in a barn. Later on he went with a few of his friends to Bruges, where he caught the train for Ostend, and came over to Dover, thence proceeding to Margate. Smith and his friends were left behind at Bruges. Round 1. — Slavin stood over Smith with a longer reach. Both sparred cantiously at the opening, Slavin at length leading off and landing heavily on Smith's chest, jumping back out of danger. Sparring again Slavin landed full on Smith's mouth. Heavy in-fighting followed, the men closing and falling together. When Slavin rose it was seen that he was bleeding from the mouth. Time, 1min. 30sec. Round 2. — Slavin fought Smith right into his own corner. There was a disgraceful scrimmage there among Smith's friends, Slavin being badly used. Both men fell together. Time, 15sec. Smith's party shouted out that their man had been spiked by Slavin's boots. The referee, thus appealed to, declared that the men had spiked each other. Round 3. — Smith showed to better advantage in this round, getting home both right and left twice in quick succession on the Australian's body. Sharp close in-fighting followed, Smith going down before a terrific right-hander. (First knock-down blow to Slavin.) Round 4. — Both men were blowing when they came up for this round. The fighting was again fast and furious, Smith at length cross-buttocking Slavin. The Englishman, however, did not fall on him. Round 5. — A light round, Smith going down before a light blow. Time, 11sec. Round 6. — Slavin came up very determined, and forced the fighting at a great pace. He drove Smith all over the ring, landing with his right a heavy blow over the right eye. Smith went down bleeding freely from a gash on the forehead. Round 7. — Smith came up stronger and did some of the forcing work, beating Slavin for a moment on to the ropes. While in this position one of the crowd of roughs deliberately kicked the Australian, who, however, took no notice of the cowardly attack. Both the combatants got away from the ropes and fought to the middle of the ring, where Smith slipped, and both were taken to their corners. Round 8. — Slavin did the opening work in this round, driving Smith round the ring and finally into his corner, where, as usual, his friends were ready to protect him. Smith came out again, when Slavin landed heavily with right and left, and Smith sought the ground. Round — 9 There were heavy exchanges from the outset, Slavin giving his man no rest, and driving him back into his corner. While there one of the mob struck Slavin on the head a violent blow. Time, 1min. Round 10. — This was a far more sportsmanlike round. Smith stood up well in the centre of the ring, and fought it out without the assistance of his friends. There was hard fighting from first to last of a close order, both getting home some terrific body blows. Both fell together. Round 11. — Smith looked tired and led off feebly while Slavin returned with right and left on the head, cutting open the Englishman's cheek on the left side. Smith landed his left again, Smith countering heavily. Smith then rushed upon the Australian, who met him with a severe blow on the mouth, and then sent him down with a terrific right-hander. Round 12. — The disturbances at the ring had now become so unbearable that the referee cautioned the seconds to keep to their corners, and not to interfere with the principals during the progress of the round. The round was of the cautious order, Smith finally being sent to grass again from a heavy right-hand blow on the jaw. Time, 1min. 30sec. Round 13. — Slavin again did all the leading, fighting the Englishman round the ring, and forcing him into his corner. There were some heavy exehanges, Smith's friends again assisting their man by hitting freely at Slavin. Round 14 and last. — Just a second before "Time" was called, Slavin, remarking on the treatment he had received, said, "Are you Englishmen, boys?" This was received with derisive shouts from Smith's party, and then, in an instant, a cry of "Police" was raised. The whole of the Smith party instantly decamped, hurrying their man along with them. Slavin, however, declined to stir, and his friends shouted that it was only a ruse to stop the fight. After a time the Smith  party returned, and Slavin then said to Baldock, the most prominent of Jem Smith's seconds, "Why don't you give me fair play?" Slavin's seconds claimed the fight, but the referee ordered them to fight on. The tactics of the Englishman's supporters were now very evident, but Slavin, who was only anxious to have the fight out to an end, advanced into the  centre of the ring, and again beat the Englishman back into his own corner. A scrimmage ensued, both men landing heavily, and the mob in Smith's corner then closed upon Slavin, who was again kicked and struck. The Australian, however, paid no attention to anyone except Smith, and he finished up the round by throwing him heavily. The referee then said, "I shall refuse to act any longer. This man" — pointing  to Slavin — "can't have fair play. I declare it a draw." Smith seemed well at the finish, and Slavin was certainly full of fight and disgusted at having been robbed of victory by the cowardly attacks of roughs. The Australian had fought in the fairest and most plucky manner throughout, forcing the Englishman back into his corner in nearly every round, and keeping him there. Here the fight came to an end, the referee exclaiming, "I shall refuse to act any longer. I shall declare it a draw." There was considerable surprise among Slavin and his supporters, and the Australian said, "I came 16,000 miles to win, and why don't you give a man a chance?" After some little delay the company dispersed. The time at the end of the fight was eight minutes to nine. Mr. Cecil Raleigh, hon. secretary of the Pelican Club, 21, Denman-street W., writes as follows:— "As an impression prevails that the Smith and Slavin fight was arranged under the patronage of this club, I should esteem it a favour if you would allow me to state emphatically that the Pelican Club gave no countenance to the affair in any way whatever, and had nothing to do with it." Directly the news became known in London the greatest indignation prevailed in all the clubs at the dastardly way in which Slavin had been treated. Subsequently some forty or fifty gentlemen proceeded to the Pelican to demand the instant and public repudiation on the part of the committee with any official cognizance of the arrangements for the fight, and also for the summary punishment of those who had dragged prize fighting down to the lowest depth of degradation and blackguardism. In accordance with these demands, and in full sympathy with them, those members present, conjointly with the proprietor, immediately sent out telegrams summoning an extraordinary meeting of the committee. That Slavin has now a right to the title (empty though it be) of "champion" is clearly supported by the 24th rule of the Prize Ring, which runs as follows:— "Any pugilist voluntarily quitting the ring previous to the deliberate judgment of the referee being obtained shall be deemed to have lost the fight." It seemed a pity that Mr. Vesey should not have had sufficient support to enforce what was uadoubtedly the judgment of all impartial spectators of round thirteen. Arrival of Slavin at Margate. Slavin arrived at Margate at half-past seven on Monday evening, and met with a flattering reception. During his training in the town he had become a general favourite with those who took an interest in the event. Sympathy was almost wholly on his side, and during the day news was anxiously awaited. At the station he was met by a four-in-hand and the town band, and proceeded to the Elephant Hotel, the band playing, "See the conquering hero comes." Along the Parade, on which was assembled a large crowd of people, he was loudly cheered. At the Elephant Hotel, there was a large crowd of people, and the reception was most enthusiastic. Slavin briefly addressed the gathering, thanking them for the reception he had received. His intention, he said, when [Col. 4c–5a] he left England was to win the championship or lose it fairly, and he was sorry that the fight had ended in such a fiasco. Inside the hotel the scene was very exciting, and Slavin received the hearty congratulations of his friends at the slight punishment he had received. He then left for the Nayland Rock Hotel, his quarters, and on the road was loudly cheered. Upon arriving at the hotel, Slavin retired, accompanied by his second, Joss Cosnett, after which the correspondent of the Press Association was introduced to him. The first question put was, "Well, Slavin, how have you fared?" "Very badly," responded the Australian. "As far as the roughs were concerned, I never witnessed anything more disgraceful in all my experience. My treatment at their hands has been most cruel, and nothing I could say would sufficiently emphasize what I mean. I am very pleased indeed at  the reception I received on my arrival at Margate. Nothing could have been more enthusiastic. You see what punishment I have received. It is not from Smith so much as it is from the outsiders." — Joss Cosnett: Smith did not bit him any more than I am hitting you. The conduct of the roughs round the ring was shameful. Slavin: The treatment I have received from them was most unmanly. I am sure the roughs never meant it to be fought out. They intended to have a draw if they found their man losing. Several of Smith's backers, including two well-known noblemen, were disgusted, and threw his colours away and put mine on, as a protest, I suppose, against the treatment I had received. To speak the truth, I would not like to see a dog treated as I was. All I am anxious for now is to meet Sullivan for the championship of the world for £500 to £1,000, or anyone else. I am willing and ready to meet and fight anybody for the championship before I go back to Australia. The Pelican Club and the Fight. A meeting was held at the Pelican Club at one o'clock on Tuesday afternoon. At the conclusion the hon. secretary, Mr. Cecil Raleigh, furnished the following report:— "In view of the reports of what had occurred at the Smith and Slavin fight a special meeting of the committee of the Pelican Club was instantly convened by telegraph for this afternoon. There was a large attendance of the committee, among those present being the Marquis of Queensbury, Mr. John Corlett, and other well-known sportsmen. It was unanimously determined to address a letter of sympathy to Frank Slavin, expressing the appreciation of the committee of the courage he exhibited, in face of the most  blackguardly conduct which ever disgraced the ring side. The committee added that they fully recognised that he had indisputably established his claim to the championship of England, and they further informed him of their intention to present to him a belt and purse in recognition of his pluck. The committee then determined that Mr. John Fleming, late manager to Jem Smith, who had hitherto acted as master of the ceremonies at the Pelican Club, should be suspended from his office until such time as he should afford an explanation of his connection with the Smith and Slavin fight, which explanation would be laid before a general meeting of the members of the club on Tuesday, January 6th. The indignation of the members of the club knows no bounds, and every effort will be made to discover who were the real instigators of the disgraceful business." It is most likely that the belt and purse will be presented to Slavin on January 14th, when the club move into their new premises. The following letter has been addressed by the pugilist, F. P. Slavin, to the Pelican Club:— "In reply to your very kind and encouraging letter, accept my warmest thanks for the high compliment you are about to pay me in presenting me with a belt, called the Champion of England belt. You may rely it will be my duty, as it has been all through my career, to do my best to win any contest I may enter into in a fair and manly manner. — Again thanking you, I am, sir, yours truly, "F. P. SLAVIN. "Nayland Rock Hotel, Margate." Mr. Fleming's Statement. Mr. Fleming states that the fight was arranged before the boxing match with Jackson. He went over to Belgium and selected the ground. As regards the rough element present, he did not know one of the men. No doubt they were engaged by some friends of Smith. The only persons who went across with them were four or five gentlemen. All connection between Smith and him had ceased, as he felt that he could not act in any way for Smith after what had occurred. Every fight that he had previously had the management of had always been brought off without the intrusion of any of the rough element at the ring side. He took no part in the proceedings, being merely there as a spectator, and he had not seen Smith since the fight. He did not think that he should have any difficulty in proving that he had no connection with the disgraceful proceedings at the ring side. The Preliminary Arrangements. The preliminaries of the match will, perhaps, be interesting. When, in 1885, Jem Smith, who had made a name among English heavy-weight boxers, met and defeated Jack Davis, of Birmingham, there was a sign of a revival of pugilism in this country. This was increased when Smith fought Alf Greenfield, and, although the battle ended in a draw, it was not long before the "lost art" was freely discussed, and there was every appearance of the revival of the prize-ring. Smith, as will be well remembered, fought a memorable battle with Jake Kilrain, who came from America to wrest the championship honour from the Englishman. John L. Sullivan, the Boston Boy, soon followed, and, although he failed to beat Charles Mitchell, his claim to the title of champion of the world was made good last July, when be met and defeated Kilrain. Then came new stars in the firmament of boxers, but glove-fighting had almost extinguished the "old style." Prominent among the late arrivals were Peter Jackson, a coloured man, and Frank P. Slavin, both hailing from Australia. Their records were of the highest calibre, Slavin having been successful in all the nineteen contests in which he had engaged, either with gloves or with bare hands, while Jackson's was but little less noticeable. The latter, however, carried all before him in America, and then sought fresh fields in England. Only a few weeks ago he vanquished Jem Smith in a couple of rounds. Slavin arrived in London a week prior to Jackson, and, after a lengthy wait, he was accommodated with a match. No one but W. Goode cared to meet him with the gloves, and Goode was easily disposed of. After signing articles to fight Jem Smith under prize ring rules, both men went into training, Smith at Newmarket, under the care of Jem Howes, and Slavin at Margate, with Fred Symes as mentor. The most difficult part of the arrangements had yet to be settled, and it was not without great trouble that a battle ground could be selected which afforded facilities for the accommodation of a party of sportsmen to witness the contest. At length a point was pitched upon near the Belgian capital, easy of access and fairly safe from interference. Another difficulty now arose over the appointment of a referee, and no less than five good men were named, all of whom were in turn objected to by Smith. The possibility of this having been foreseen it had been stated in the articles that the two parties failing to agree, the stakeholder, Mr. C. W. Blacklock, should appoint that official. This he did with satisfaction to both parties, naming Mr. J. Vesey, a well-known sporting man, to act. The stakes had then been increased to £500 a side. There is a great difference in the physique of the two men. Slavin stands 6ft. 1in., and scales in condition thirteen stone, is a very muscular athlete, and particularly quick on his legs; while Smith is of the sturdy order, and is only 5ft. 8¹/₂in. high. His weight when fit is 12st. 10lbs., and although his muscles are very massively developed, giving proof of great strength, he has not the quick hitting power of the Australian. Performances of the Men. Frank P. Slavin, the champion of Australia, was born on January 27, 1863, at Maitland, N.S.W. He stands 6ft. 1in. in his stockings, and in condition scales 13st. 5lb. or 13st. 6lb. Shavin served his time or apprenticeship to a coachbuilder and blacksmith, and first came out as a pedestrian. After winning several competitions as an amateur, Slavin's first fight was with knuckles against M. Power for £50 a-side, and he won after seven rounds, lasting thirteen minutes. He then beat Jem Burke with two-ounce gloves for £200 a-side and the championship of Queensland, winning in three rounds. This was in December, 1885, and in 1886 he went to Sydney and entered into an engagement with Larry Foley. Here Slavin met Taylor, a pupil of Jackson's, for a purse with small gloves, and stopped him in two rounds. He was then matched with a big follow named Bligh for £10 a-side, and beat him in one round. After a rest of two months articles were signed for him and Mike Dooley to box for £100 a-side, and Slavin won in nine rounds. He next met Mike Costello, an American, a good man, and after a big battle in Sydney, lasting two hours and a half, a draw was the result. Another match was made for £400, and £50 a-side was posted, but Costello forfeited this. Afterwards Slavin's backers matched him for £25 a-side to stop Costello in six rounds, but the latter is very clever and tricky, and lasted the time. Subsequently Slavin journeyed to Sydney, and finding Mike there, challenged him again. The result of this was a match for £100 a-side with skin gloves, which Slavin won in twenty minutes. Slavin at this time had any amount of backing, and issued a challenge to fight Peter Jackson for £250 a-side and the championship. Jackson's party wanted a match with gloves for a purse. They could not, however, come to terms. In January last year the Australian made a trip to New Zealand. The first man put up was Smith, who was backed to stand four rounds, but he had had enough at the end of the first. In Dunedin Slavin beat a big fellow in four minutes, and journeyed a long distance to fight Laing, the champion. The pair were matched for  £200 a-side, and fought with two-ounce gloves at Wanganui, Laing failing to come up at the end of the fifth round. After this Slavin returned to Melbourne, and met Jack Burke, but after Slavin had had all the best of it, the contest was declared a draw. Mike Dooley was now in Sydney, and issued a challenge to him. This led to a match for £200 with small gloves, which ended in Mike being knocked out in 2min. 40sec. Slavin returned to Melbourne, and fought Burke, Slavin undertaking to stop him in six rounds; £200 a-side was put up and the two fought with six-ounce gloves, and agreed to divide the gate, and Burke was beaten in the middle of the third round. Previous to this Billy Farnan, the conqueror of Jackson, and Slavin, fought for £200, with the result that the latter added another winning bracket to his name, Farnan failing to answer to the call of time in the third round. He then received forfeit from Woolf Bendoff. An easy victory over Bill Buck in two rounds followed. He then came to England, and his late victory in his glove fight with the plucky young Englishman, W. Goode, must still be fresh in the memory of our readers. Jem Smith was born in Whitecross-street on January 21, 1863. He stands 5ft. 8¹/₂in. high, and weighs in condition 12st. 10lb. Round the chest he measures 43¹/₂in.; waist, 36¹/₂in.; hips, 41in.; thigh, 24¹/₂in.; calf, 16³/₄in.; biceps, 15¹/₂in. For some years he was employed in one of the metropolitan timber yards, but developing a taste for boxing after one or two rough-and-tumbles with his fellow-workmen, he was taken in hand by Jack Knifton ("eighty-one tonner") and later by Mr. F. Grimm, of the Central Club. His first success was in a competition at the Griffin, Shoreditch. Later on he beat Snowey, of Holloway, and was then matched to box Harry Arnold with gloves for a £10 purse. The affair was looked upon as a good thing [Col. 5c–6a] for Smith, but it took him nearly an hour to polish off this last opponent, though he had slightly the best of the encounter from start to finish. Smith's next engagement was with Woolf Bendoff to box to a finish with gloves for £25 a-side, which came off at an East-end club. In this contest Smith injured his right arm, but, nevertheless, proved successful at the end of twelve  rounds. Smith also won Tom Symonds's All-comers' Competition on February 26, 1885, at Bill Richardson's, defeating Sugar Goodson, Jack Wannop (the wrestler), and Tom Longer. Smith's next battle was with Jack Davis, for £100 a side and the championship, on the turf, and came off on the borders of Surrey and Sussex on Wednesday, December 17. In all six rounds were fought, occupying 7min. 56sec., Davis being knocked out of time with a swinging right-hander. He subsequently met Alf Greenfield, of Birmingham, for £300, at Maisons-Laffite, near Paris, on Tuesday, February 16, 1886. Thirteen rounds were fought, mostly in Smith's favour, and the men fell, whereupon a cry of foul was raised by Greenfield's party, and a crowd of roughs broke into the ring, stopping the fight. The referee (Jem Mace), at the request of the principal backers of the men, agreed to decide the battle a draw. Soon after Smith was matched to fight Knifton, the "eighty-one-tonner" as he is called. This proved a fiasco. The memorable struggle between Smith and Kilrain, brought off on an island in the Seine, came next, darkness putting an end to the affair, which also resulted in a draw, after the men had faced each other for 106 rounds, on December 19th, 1887. This brings us to his ten-round glove contest with Jack Wannop, Smith laying £250 to £200, and winning easily. After which, as all the pugilistic world knows, Smith was easily defeated by the coloured champion, Peter Jackson, in a glove fight at the Pelican Club, the last named winning on a foul by Smith, who was at the same time well beaten.<ref>"The Great Prize Fight. £1,000 in Stakes. Brutal Scenes in the Ring." ''Reynolds's Newspaper'' 29 December 1889, Sunday: 1 [of 8], Col. 4a–6a [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000101%2F18891229&page=1&article=006&stringtohighlight=mandeville+viscount. Same print title, n.p.</ref> </blockquote> === The ''People'' === On Sunday, 29 December 1899, the ''People''<blockquote>Disgraceful Scenes. Expressions of indignation. The prize fight between Jem Smith, who poses as the fistic "champion of England," and Frank Slavin, the Australian champion, took place early on Monday, and resulted in perhaps the most disgraceful scene ever witnessed in connection with the history of the prize ring. Various spots, both at home and abroad, were from time to time named as the possible battle-field, but finally it became known to a certain select few that an English gentleman, Mr. Atkinson-Grimshaw, residing near Bruges, Belgium, had placed his grounds at the disposal of the combatants. In London it soon became known that the principal supporters of the Englishman had caused a number of Birmingham ruffians to be hired for the purpose of making a "strong corner." The betting changed directly to short odds on the Australian, and also evens, while  offers of 30 to 20 that "Smith did not lose" proclaimed that some ugly and disreputable manœuvres would be attempted. The ring was pitched on a splendid piece of turf — the lawn tennis ground, in fact — and about forty persons assembled, including Viscount Royston, [[Social Victorians/People/Mandeville|Viscount Mandeville]], Mr. Abington, Mr. Harris, Mr. W. Riley, Mr. F. Kotchie, Mr. Ike White, the Hon. M. Sandys, Mr. E. Bayley, Mr. C. Parsons, Mr. J. Kilby, Mr. C. Morton, and other well-known "sports." Smith was dressed first, and and [sic] had to wait a few minutes for Slavin. The Englishman appeared in white flannel drawers, white socks, and lace-up boots, while the Australian wore black drawers, blue socks, and lace-up boots. Harper and Baldock were seconds, Howes bottle-holder, and Mr. Fleming umpire for Smith; Cosnett and Bob Kirby, Mr. Taylor, and Mr. W. Riley acting in similar capacities for Slavin. Mr. Joe Vezey officiated as referee and Mr. Calder as timekeeper. The Fight. The men were in the ring at 8.25, and ten minutes later the fight began. After the first two rounds everything went in favour of Slavin, who in the third round knocked Smith clean off his legs with a terrific right-hander. He repeated this operation four or five times subsequently, and surprised many of the spectators by the determined way in which he fought. Smith looked very serious on coming up for the fourth round. At this time a suspicious movement was noticeable among the brigade of Birmingham ruffians, and one of them came round to the colonial's corner with no good intentions. Had it not been that Mick Taylor and Frank Hinde kept zealous guard over all the water provided for the use of the combatants, there is no knowing what fiendish trick might not have been perpetrated. Getting to close quarters, Slavin delivered heavily right and left on Smith's body, the latter being very slow in responding to this vigorous attack. He had, however, other assistants, for a vile ruffian from over the ropes deliberately struck Slavin a blow on the head. A shout was at once raised, but when charged with it the rascal denied that he had done anything. A scuffle ensued between the men, and to escape from the difficulty Smith cross-buttocked his opponent, who fell. In the fifth and sixth rounds Slavin again brought Smith to the ground, and made a nasty gash on his forehead. All this time the most horrible language proceeded from Smith's corner. In the seventh round a desperate rally took place, during which Smith fought Slavin on to the ropes, and there held him. Here was a grand opportunity for the miscreants, who did not fail to make use of it. One of them kicked Slavin repeatedly, and others beat him about the head, knuckle-dusters and life preservers being used. Slavin during the progress of the eighth round further received a couple of smart blows from a stick which a cowardly ruffian carried. Taking not the smallest notice of these interruptions Slavin pursued his legitimate opponent, both Smith's seconds following him about and jeering in his face. The referee entered the ring, and cautioned the seconds to move away. This had very little effect, and in the midst of half-arm fighting of a very severe kind, Smith was one more brought to the ground. In the ninth round the Australian again ventured into Smith's corner, and the fighting brought him close to the ropes. The  Birmingham mob here set about Slavin with great brutality, kicking him and punching him on all parts of the body. Getting away from the ropes Slavin let go the right, and, reaching Smith's mouth, caused the blood to spring forth profusely, bringing the Englishman to grass. The tenth and eleventh rounds were not quite so exciting, but in the twelfth Slavin drove his right with terrific force on to Smith's chin, knocking him clean off his legs. In the thirteenth round the Australian doubled Smith up with a fearful blow under the left ribs, and the Englishman's friends, seeing that Smith was almost beaten, raised a cry of " Police!" Smith was hurried from the ring, but Slavin and his friends refused to budge, and after "Time" had been called they claimed the fight. The referee, who appeared afraid to give a just decision, was surrounded by partisans of Smith, who had meanwhile come back, and eventually ordered the fight to proceed. The next round, the fourteenth, was the last. Slavin fought in a most determined fashion, and when he was punishing Smith heavily, the latter caught the Australian round the waist and held him on to the ropes, whilst the ruffians standing round beat and kicked him in a most cowardly fashion. Amid cries of "Foul," the pair fell to the ground, and, on the men taking their corners, the referee said he would act no longer, as it was perfectly clear Slavin was not to have fair play. This created immense excitement, during which the referee declared the fight a draw, and, crossing to Slavin, said, "I do not want to stay here to see you killed." Afterwards the roughs tried to get at Slavin, who, however, managed to hide in a barn. Later on he went with a few of his friends to Bruges, where he caught the train for Ostend, and came over to Dover, thence proceeding to  Margate. Slavin's Opinion of his Treatment. The following conversation took place during an interview with Slavin, a few hours after the fight:— Did you expect any trouble at the ring  side? — Slavin: Yes, I was prepared for that, as I was constantly receiving letters of a threatening nature, and though these things as a rule are of no account, I had reason to believe there was some truth this time. Besides, I had not forgotten the affair at Astley's Theatre. — Do you feel any effects of the fighting? — Slavin: The fighting? I feel nothing of what I got from any one in the ring; it's what those beauties gave me outside. The only time Smith hit me in anything like form was on the jaw. — Why did you persist in going to his corner? — Slavin: I wanted to get the affair over and enjoy my Christmas dinner, and I knew if the fighting was left to Smith I should want it served in the ring. — Of course you heard a mob was got together for Smith? — Slavin: Yes, I knew all about that, but I relied on British fair play, and expected the referee to do his duty. Directly I got in the ring I saw what the game was, and knew my only chance was to knock Smith out. — What do you think of Smith? — Well, I think so much of him that I'll bet him £200 I stop him in six rounds, but we must have no more private shows. I've had enough of that business. — l suppose you have a poor opinion of English fair play? — Slavin: I have been treated like a prince generally, but I can see the fighting men are easily led astray, and I expected trouble directly Smith objected to a referee. If we served an Englishman in the same manner in Australia we should get drummed out of the town, and rightly too. — What are your plans for the future? Well, I shall stay in England some time and challenge Sullivan, and you might as well cable it over to America for me. — With the gloves? — No. I want to fight him with the knuckles. I think I should get fair play out there. Indignation in London. Directly the news became known in London the greatest indignation prevailed in all the West-end, [Col. 4c–5a] clubs at the dastardly way in which Slavin had been treated. Subsequently some forty or fifty gentlemen proceeded to the Pelican to demand the instant and public repudiation on the part of the committee with any official cognisance of the arrangements for the fight, and also for the summary punishment of those who had dragged dowr [sic] a manly pastime to the lowest depth of degradation and blackguardism. In accordance with these demands, and in full sympathy with them, those members present, conjointly with the proprietor, immediately sent out telegrams summoning an extraordinary meeting of the cornmittee. The Pelican Club Meeting. At the special meeting of the committee of the Pelican Club it was unanimously determined to address a letter of sympathy to Slavin, expressing the appreciation of the committee of "the courage he exhibited in face of the most blackguardly conduct which ever disgraced the ring side.["] The committee added that they fully recognised that he had indisputably established his claim to the championship of England, and they further informed him of their intention to present to him a belt and purse in recognition of his pluck[.] The committee determined that Mr. John Fleming, late manager to Jem Smith, who had hitherto acted as manager of the ceremonies at the Pelican Club, should be suspended from his office until such time as he should afford an explanation of his connection with the Smith and Slavin fight, which explanation would be laid before a general meeting of the members of the Pelican Club on Tuesday, January 7th. It is most likely that the belt and purse will be presented to Slavin on January 14th, when the club will move into their new premises. While Salvin was at the Stock Exchange on Tuesday, a subscription in his interest was started, and £110 was quickly subscribed. Slavin Challenges J. L. Sullivan. Frank Slavin, the champion of Australia, is prepared to meet John L. Sullivan, under London prize ring rules, for £500 or £1,000 a side and the championship of the world. Slavin has lodged a sum of £100, and will contest the title with Sullivan in either America or Australia in six months from signing articles. We have cabled this challenge to Mr. R. K. Fox, of New York, and the money lodged with him or the editor of the ''Sportsman'' will lead to a match.<ref>"The Smith-Slavin Fight." ''The People'' 29 December 1889, Sunday: 16 [of 16], Col. 4a–5a [of 5]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000729%2F18891229&page=16&article=150&stringtohighlight=mandeville+viscount. Same print title and p.</ref></blockquote> === The ''Sportsman'' === On Monday, 30 December 1889, the ''Sportsman'' printed a list of people and organizations that had contributed to the "testimonial" fund for Slavin as well as some letters to the editor about the Slavin-Smith match:<blockquote> A committee meeting of the above was held on Saturday afternoon, Mr W. J. Innes in the chair.  There were also present Mr W. Riley, Mr Fred H. [Gala?], Mr C. Parsons, Mr A. Butler, Mr M. J. Harrow (Margate), Mr Ike White, Mr E. C. Irish, and Mr G. T. Dunning (hon. sec. and treasurer). The chairman read a letter from Mr John Lees, regretting his inability to attend owing to illness, whilst the remaining committeeman, Mr E. W. Bayly, was absent in Paris. The appointment of the hon. sec. and treasurer was confirmed by the committee, and after some discussion it was decided to close the subscription-list on Monday, January 20, and to present the proceeds to Slavin at the Cambridge Music Hall, Bishopsgate-street, on a day to be named. Other business of minor importance was transacted, and after the next committee meeting had been fixed for Wednesday, January 15, the meeting closed with a vote of thanks to the chairman. Additional subscriptions to the fund, which now reaches 300''l''., will be found appended [names set as unordered list to save space, £ ''s.'' ''d.''] * Lord Mandeville 2 2 0 * Lord Royston 2 2 0 * Lord James Douglas 2 2 0 * Hon. Michael Sandys 2 2 0 * Fred Kotchie 2 2 0 * Mr Ike White 2 2 0 * Mr W. Riley 2 2 0 * Mr C. Parsons 2 2 0 * Mr J. Kilby 2 2 0 * Mr Frank Hinde 2 2 0 * Proprietors of The Sportsman 2 2 0 * Mr. J. Purdey 2 2 0 * Mr. E. W. Bayly 2 2 0 * Messrs H. A. Domby and Son 2 2 0 * "Caption Coe" 2 2 0 * Mr C. W. Bulpett 2 2 0 * Mr P. W. Carr 2 2 0 * Mr W. Morley Pegge 2 2 0 * W. D. S. 2 2 0 * J. E. S. 2 2 0 * Mr W. H. Grenfel 2 2 0 * Mr Quartermaine East 2 2 0 * Mr H. H. Hungerford 2 2 0 * Mr Noel Fenwick 2 2 0 * Sir John Leslie, Bart. 2 2 0 * Mr T. Brinkman 2 0 0 * Mr Calder 1 1 0 * Mr H. W. Hill 1 1 0 * Mr John Young 1 1 0 * Mr D. A. Neilson 1 1 0 * Mr W. Neilson 1 1 0 * Mr Julius Simon 1 1 0 * Mr J. Edge 1 1 0 * Mr H. Marshall 1 1 0 * Mr F. Aynsley 1 1 0 * Col. Hon. Wellesley 1 1 0 * Mr Charles Hawtrey 1 1 0 * Mr W. F. Ashton 1 1 0 * Mr Barratt 1 1 0 * Old Durham Ox 1 0 0 * Sir John Willoughby 1 0 0 * A friend, per C. H. A. 0 10 6 * Mr Ben Giles 0 10 6 * Mr Tom Vale 0 10 6 * [E.?] W. 0 10 6 * Officer 0 10 0 * Per Mr Ike White, Exchange Club: ** S. W. 2 2 0 ** Mr G. B. Knight 1 1 0 ** Mr A. Powles 1 1 0 ** Mr S. Blandford 1 1 0 ** T. F. W. C. 1 1 0 ** Mr Leo Harward 1 1 0 ** Mr J. Harward 1 1 0 ** Mr H. Harward 1 1 0 ** Mr [Monteagle?] [Moutcagie??] 1 1 0 ** Mr C. Orate 0 10 6 ** W. G. P. 0 10 6 ** H. R. T 0 10 6 ** Mr Josiah Smith 0 10 6 ** W. H. R. 0 10 6 ** Mr R. Wilson 0 5 0 * Per Mr M. J. Harlow, Margate: ** Mr A. H. [Cosi? Coni?] 2 2 0 ** Mr J. Thurston 1 1 0 ** Mr J. A. Fagg 1 1 0 ** Mr F. [Miles?] 1 1 0 ** Mr Adolphe [Drineqbeir?] 1 1 0 ** Mr Ernest [Drineqbier?] 1 1 0 ** Mr Lacy Brown 1 1 0 ** Mr Algy Brown 1 1 0 ** Mr M. J. Harlow 1 1 0 ** An Admirer 1 1 0 ** Mr J. W. Robinson 1 1 0 ** Mr W. Searles 1 1 0 ** Mr J. Smith 1 1 0 ** Mr J. Hume 1 1 0 ** Mr J. Painter 1 1 0 ** A Scotchman 1 1 0 ** Mr J. Mundell 0 10 6 ** Mr Bob Redman 0 10 6 ** Mr G. A. Body 0 10 6 ** Mr J. Phipps 0 10 6 ** Mr J. Doughty 0 10 6 ** Old Fisherman 0 10 6 ** Mr Joe Knott 0 10 6 * Per Mr B. J. Angle ** Some mebers of the Stock Exchange 125 0 0 ** Hr Henry J. Turner 2 2 0 * Per Mr W. J. Innes: ** Mr Sidney Fry 2 2 0 ** Mr W. J. I. 2 2 0 ** Mr W. Schlesinger 2 2 0 ** Mr Joseph Thompson 2 2 0 ** Mr Barney Thompson 2 2 0 ** Mr L. Meyers 2 2 0 ** Mr W. Shoe 2 2 0 ** Mr George Cooper 2 2 0 ** Mr J. T. Crossley 2 2 0 ** Mr Andy Anderson 2 2 0 ** Mr G. M. T. 2 2 0 ** Mr F. R. 2 2 0 ** Mr W. Bertram 1 1 0 ** Mr J. W. Hammon 1 1 0 ** Mr Alec Harris 1 1 0 ** Mr John Isaacs 1 1 0 ** Mr Edward [Dance? Dasce?] 1 1 0 ** Mr George Blanchett 1 1 0 ** Mr F. [Leleu? Lolou?] 1 1 0 ** Mr W. J. R. 1 1 0 ** Mr H. C. 1 1 0 ** Mr A. A. M. 1 1 0 ** Mr D. W. Fowler 0 10 6 * Per Mr F. H. Gale: ** Mr R. Moore 2 2 0 ** Mr A. H. Goode 2 2 0 ** Mr [B.? E.? R.?] J. G. Goode 2 2 0 ** Mr F. H. Gale 2 2 0 ** Mr H. Ulph 1 1 0 ** Mr J. Hooper 1 1 0 ** Mr C. Kittall 1 1 0 ** Mr C. Moore 1 1 0 * Per Mr W. Riley: ** Mr Brand (Wiltshire) 2 2 0 ** Mr Charles Godfrey 2 2 0 ** Mrs Lane (Britannia) 2 2 0 ** Mr Sam Adams 2 2 0 ** B. and M. 0 7 6 * Per Mr A. Cockburn: ** Mr Richardson 2 2 0 ** Mr A. Cox 1 1 0 ** Mr Hy. Brackenbury 1 1 0 To the Editor of T<small>HE</small> S<small>PORTSMAN</small>. Sir,— From the evidence of your eye-witness reporter there seems to me the clearest possible case against Smith, Harper, and Baldock — that Smith held Slavin on the ropes while the roughs kicked and "knuckle-dustered" him, that Harper put his knee on Slavin when down, and that Baldock did likewise, and that throughout they advised Smith to stand like a coward under the protection of the savages till the instinct which filled Slavin's manly bosom prompted the honest outburst to Smith, "Come and have a round." The duty for sportsmen to fulfil with the assistance of their representative journal, is, firstly, to see that Slavin is elected Champion and that he is handsomely recompensed, and that these so-called "seconds" should be properly punished and our splendid timber-yard Champion put in his proper place. The names of those who hired the roughs should also be published. I have spoken to at least fifty patrons of boxing shows, and one and all have made the most positive and determined objection to supporting any entertainment where the three men named above are concerned directly or indirectly. They, by their own stupidity and cupidity, have put the last nail in their own coffin, I hope. With regard to the referee, this individual is decidedly unsatisfactory. He allowed Smith to bolt when the cry of "Police" was raised without disqualifying him in any way, and then put an end to the business by declaring it a draw. Now, if the said referee is not a determined or courageous man, then he acted to the best of his judgment, for he was afraid of personal violence, having literally to escape to London; but on his arrival here, I and numberless others naturally expected some explanation or a reversal of his decision. The whole sporting community are on the tiptoe of excitement, and Mr Vesey in the coolest  possible manner washes his hands of the affair, declining absolutely to expose any opinion. This is rather rough on the public considering that be consented to act as referee of his own free will, and he is no chicken in such matters. He does not tell us whether he is aware that he has the power to reverse a decision given under fear; nor does he say whether he still considers the decision made on the spot a happy one. How was it that no steps were taken to protect the referee? There is no legitimate courage in the Brummagem rough. He is an imposter. With assistance of our excellent so-called Champion, and about another ten, armed with knuckle-dusters, he will doubtless attack Slavin, and if a torrent of filthy, cowardly abuse could kill he would beat Slavin single-handed. One of these gallant gentry actually returned to Birmingham without going to Bruges, being positively afraid to chance crossing the tiny stretch of sea. An American reader will bear me out that had our unsatisfactory referee been under the protection of one single genuine Nebraska "tough," as they are called out there, he would, without uttering one word of bad language, have cleared out the lot had they attempted violence to his charge. But it would never have come to that, for the sight of a real, genuine armed rough, with determined set features, would have struck terror into the hearts of the pluckless Brum shoddy bully, with the proverbial dull, stupid, animal-like pudding face. As an Englishman I [Col. 1c–2a] positively feel guilty among my American friends when they ask me what about my vaunted British fairplay, and I quite fail to see or understand how "seconds" — no matter, for argument's sake, how dishonest they may be can such fools as to kill the goose which lays their golden eggs. Prize-fighting and boxing are their bread-and-butter, and some of those who accepted the assistance of the roughs in the recent important international fight must have surely prognosticated that trouble and disgrace would follow, and they of all men should have been the last to wantonly risk breaking up one of our favourite English sports. In conclusion, contrast the courage of the two men. Slavin practically fought about six men, not knowing the moment that one well-directed blow from a "duster" might have cost him his life or lost him the fight. Think of his manly appeals to the cowards for a few minutes' fairplay. I only wish they each had to have four rounds singly with him! — Yours, &c., A Lover of Boxing. To the Editor of T<small>HE</small> S<small>PORTSMAN</small>. Sir, — Previous to the late show of ruffianism I was in sympathy with and respected Smith as the Champion, but I am grieved to say that nothing of late years has so thoroughly disgusted me as the ill-treatment which was meted out to Slavin by those who disgrace not only sport but the very name of man. I sincerely hope that Slavin will still continue to think that one of the dearest wishes of the true sportsman of this country is to see fair play. I enclose my mite in the shape of one guinea, and subscribe myself, yours, &c., Leicester, December 28. J. Barrett. To the Editor of T<small>HE</small> S<small>PORTSMAN</small>. Sir, — Herewith I inclose cheque 1''l''. 1''s''. to the Slavin Fund, and hope that his manly and honourable conduct will be well rewarded. I cannot, however, agree with those who hope "that we have seen the last of prize-fighting," and other sentiments of the kind. It will be an evil day for England when the fighting instinct dies out from among her sons. No, let us rather hope that the Slavin-Smith ''fiasco'' will be the beginning of a new era, and that for the future fights will not be allowed to take place without proper ring-keepers, as in the days of Spring, Langham, and Bendigo, and that the Championship of England will not be long without a native defender.—Yours, &c., J. W. B. C., Junior Carlton Club, December 27. To the Editor of T<small>HE</small> S<small>PORTSMAN</small>. Sir, — l beg to inclose you the sum of one guinea, my subscription to the Slavin Fund. I was indeed sorry to read of the outrageous and murderous treatment Slavin received from Smith's supporters, which support was tacitly sought after by Smith not leaving his corner and meeting his man in the centre of the ring, as any Englishman should have done that presumed to call himself "England's Champion." I feel quite certain that had this outrageous conduct passed away without the strong condemnation it received at all good sporting men's hands in this country, and the hearty and the thoroughly unanimous sympathy expressed for Slavin, the good feeling and perfect bon accord that has existed between the sporting fraternity of the two countries, New and Old England, would soon have ceased to exist. Australians are great stickers to and warm supporters of England and the English, and they will all feel most keenly the slur cast upon "British fair-play and courage." — Yours, a lover of it, Sydney Galvayne. York, December 26. To the Editor of T<small>HE</small> S<small>PORTSMAN</small>. Sir, — Enclosed you will cheque for one guinea as a simple tribute to Slavin, who so squarely held his own, and who should not be looked upon as a stranger in a strange country, but as a cousin Englishman, who deserves support, not only as a true sportsman but also against the fearful ordeal of ruffianism to which he has been subjected. As a lover of fair play believe me, yours faithfully, Birmingham, December 27. Tom B. Sharp. To the Editor of T<small>HE</small> S<small>PORTSMAN</small>. Sir, — Please add 9''l.'' 14''s.'' to the list I have already sent you for Slavin testimonial, and oblige, yours, &c., I. White. Exchange Club, Queen-street, Cheapside, Dec. 28.<ref>"The Ring. The Slavin Testimonial." ''The Sportsman'' 30 December 1889, Monday: 4 [of 4], Col. 1a–2b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001055%2F18891230&page=4&article=020&stringtohighlight=mandeville+viscount. Same print title and p.</ref> </blockquote> On 9 January 1890 in part of a much larger partisan report with critiques of the investigative committee, its chair and its results as well as other newspapers printing rumors:<blockquote>JOHN L. SULLIVAN ON ENGLISH FAIR PLAY. {{paragraph break}} J<small>OHN</small> L S<small>ULLIVAN</small> has been speaking his mind on the Smith-Slavin fight to some purpose. "I can't see how an English fighter can be beaten," he said. This man Smith is little better than a middle-weight, and I haven't the slightest doubt that Slavin beat him fairly. Some people wonder why I did not go to England to fight Smith. Now you understand why I insisted on meeting him in this country. In England fair play is unknown. The man with the greatest number of 'heelers' always wins or saves himself from defeat. Slavin or Jackson will, in all probability, look for a match with me when they arrive in this country, and | am perfectly willing to meet either or both of them for a proper consideration. I want a big purse, and I am not particular where I fight so long as it is in a club-house. No more law-breaking for  me."<ref>"The Late Fight. Meeting of the Pelican Club. Stormy Proceedings. The Committee Resigns." ''The Sportsman'' 9 January 1890, Thursday: 4 [of 4], Col. 3b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001055%2F18900109&page=4&article=049&stringtohighlight=mandeville+viscount. Same print title and p.</ref></blockquote> Also on January 9, the ''Sportsman'' reported on a collection made for Slavin:<blockquote>THE SLAVIN TESTIMONIAL {{paragraph break}} The subscriptions towards the above now amount to over 400''l.'', and it having been decided to close the list on the 20th, the committee will be obliged if those who have promised donations will forward the same to the hon. sec. and treasurer, Mr. G. T. Dunning, T<small>HE</small> S<small>PORTSMAN</small> Office.</blockquote> {| class="wikitable" ! !£ !s. !d. |- |Amount already acknowledged |407 |3 |6 |- |Mr E.Tabernacle |1 |1 |1 |- |H. S. |1 |1 |0 |} <blockquote>The guinea acknowledged per Mr Riley, from C. R., yesterday, should be from C. K.<ref>"The Late Fight. Meeting of the Pelican Club. Stormy Proceedings. The Committee Resigns." ''The Sportsman'' 9 January 1890, Thursday: 4 [of 4], Col. 3b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001055%2F18900109&page=4&article=049&stringtohighlight=mandeville+viscount. Same print title and p.</ref></blockquote> === The ''Huddersfield Daily Chronicle'' === On 10 January 1890:<blockquote> Mitchell and Lord Mandeville. As an addendum to the important meeting of the Pelican Club committee, on Wednesday, came a gathering of "sports" at the Trocadero, Piccadilly Circus. Lord Mandeville and Mr. Abington., who had been in attendance at Denman-street, were joined by "Pony" Moore, his son-in-law, C. Mitchell, J. Carney (the Birmingham light-weight), J. Baldock, B. Habbijam, C. Bates, &c. The party, who occupied seats in the stalls, naturally discussed things pugilistic, the talk being mostly devoted to the recent international fight between Frank P. Slavin and Jem Smith. " [sic] The Squire's opinions on the matter happened not to coincide with those of Mitchell, and high words were exchanged between the pair. Suddenly the Birmingham boxer jumped up and "went for" Mr. Abington, but did not strike him. Lord Mandeville immediately interposed and asked Mitchell to be quiet, whereupon the latter directed his attention to his lordship, and struck him sharply on the forehead. Carney and Baldock sprang to his lordship's assistance, and Mitchell and "Pony" Moore at once left the building, the whole proceedings not lasting longer than a few seconds. It soon became noised abroad that there was "something up," and a crowd gathered, but the police saw Mitchell and Mr. G. W. Moore safely across the road.<ref>"The Smith-Slavin Fight." ''Huddersfield Daily Chronicle'' 10 January 1890, Friday: 4 [of 4], Col. 6b [of 6]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0002876%2F18900110&page=4&article=071&stringtohighlight=mandeville+viscount. Same print title and p.</ref></blockquote> After the Pelican Club meetings, Slavin comments:<blockquote>On Wednesday at Westminster Aquarium, F.  P. Slavin, the colonial pugilist, who received such bad treatment at the hands of roughs in his recent prize-fight with Jem Smith, the English "champion," made his first public appearance since the fight. Mr. Frank Hinde, in introducing Slavin, said he would give an exhibition with Cosnett of Birmingham, who seconded him in his fight. Slavin was the gamest man that ever  stepped into a ring, he hoped the audience would rive him a good old English welcome. On appearing on the stage Slavin met with a most enthusiastic reception, and the three rounds' sparring with Cosnett was much appreciated. At the conclusion Slavin, in response to loud calls, bowed his acknowledgments.<ref>"Slavin at the Royal Acquarium." ''Liverpool Weekly Courier'' 11 January 1890, Saturday: 3 [of 8], Col. 5a [of 8]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0003067%2F18900111&page=3&article=042&stringtohighlight=mandeville+viscount. Same print title and p.</ref></blockquote> === ''Reynolds's Newspaper'' === ''Reynolds's Newspaper'' quotes J. L. Sullivan on the Smith-Slavin match:<blockquote>Mr. John L. Sullivan has been speaking his mind on the Smith-Slavin fight to some purpose. "I can't see how an English fighter can be beaten," he said. "This man Smith is little better than a middle-weight, and I haven't the slightest doubt that Slavin beat him fairly. Some people wonder why I did not go to England to fight Smith. Now you can understand why I insisted on meeting him in this country. In England fair play is unknown. The man with the greatest number of "heelers" always wins or saves himself from defeat. Slavin or Jackson will in all probability look for a match with me when they arrive in this country, and I am perfectly willing to meet either or both of them for a proper consideration. I went a big purse, and I am not particular where I fight so long as it is in a club-house. No more law-breaking for me."<ref>"The Recent Prize Fight." ''Reynolds's Newspaper'' 12 January 1890, Sunday: 6 [of 8], Col. 4a–b [of 7]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0000101%2F18900112&page=6&article=053&stringtohighlight=mandeville+viscount. Same print title and p.</ref></blockquote> === The ''Cork Constitution'' === About Mr G Baird (Mr. Abington) from the ''Cork Constitution'':, referring at the end to the [[Social Victorians/Boxing/Fracas at the Trocadero|Fracas at the Trocadero]] or a restaurant:<blockquote>This well-known sportsman (Mr G Baird) who is occupying an unenviable position owing to his conduct at the Smith-Slavin piece of brutality, is the largest owner of race horses in England. He has no less than 100 horses in training, and though he won £10,000 in stakes last year it is computed that he should have won £25,000 additional to even pay his way. Anent that fight which has caused such indignation in the country, a London music hall was last week the scene of a pretty disturbance. Mr Abington and Lord Mandeville occupied a box during the entertainment, and received, amongst others, Charlie Mitchell, the well-known pugilist; an angry discussion ''re'' the fight ensued, and concluded by the peer measuring himself on the floor from one Mitchell’s "lefts."<ref>"Mr. Abington." ''Cork Constitution'' 14 January 1890, Tuesday: 7 [of 8], Col. 5b [of 6]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0001648%2F18900114&page=7&article=099&stringtohighlight=mandeville+viscount. Same title and p.</ref></blockquote> === The ''Colonial Standard and Jamaica Despatch'' === This report from the ''Colonial Standard and Jamaica Despatch'' mentions fighting in the streets (at a corner in Fleet Street) and tosses in an unrelated sentence about an upcoming match between a West Indian and J. L. Sullivan:<blockquote>The disgraceful affair, called by courtesy and [sic] "International Prize Fight," which desecrated the peaceful dignity of the quaint old city of Bruges on Monday morning ought to convince people that there is nothing left to hope for in the Prize Ring. [2c–3a] At eight o'clock in the morning, Jem Smith, self-styled Champion of England, and Frank Slavin, the Australian Champion, with their seconds and parties, met in the grounds of a private gentleman to try conclusions. The "fight" lasted for twenty-five minutes, and was then brought to an abrupt conclusion by the referee declaring it drawn — he would have been killed had he given it to Slavin, who proved to be incomparably the better man. Fourteen rounds were fought in all, during the whole of which time Smith's friends and Smith's seconds worried, and at last assaulted, the Australian, who behaved quite pluckily. It is a disgrace to the name of Englishmen that this brutal scene should go forth to the world. Smith's backers knew well that he had no chance of winning, so they laid their plans to smash Slavin on their own account. It is a wonder that he was not killed — as was reported in Fleet-street at ten o'clock — for Smith's roughs struck and kicked him whenever he came near their corner. Although Lord Mandeville, Lord Rosslyn [??, s/b Royston?], Sir M. Sandys, and a few other members of the upper circle, were present at the fight, the bulk of the spectators were the refuse of the gambling rings of London, blackguards and ruffians of the deepest dye. The stakes were £1,000. So great an amount of indignation has been expressed on all sides at the treatment to which the Australian was exposed, that a subscription has been opened up for him. The West Indian, Jackson, is just leaving London for San Francisco, in order to get ready to meet J. L. Sullivan.<ref>"London." ''Colonial Standard and Jamaica Despatch'' 16 January 1890, Thursday: 2 [of 4], Col. 2c–3a [of 6]. ''British Newspaper Archive'' https://www.britishnewspaperarchive.com/image-viewer?issue=BL%2F0004059%2F18900116&page=2&article=019&stringtohighlight=mandeville+viscount. Same print title, n.p.</ref></blockquote> == Notes and Questions == # ==References== {{reflist}} kqaslcn3u55n3htve84fmyyh49qw57g 1 332493 2844947 2842215 2026-11-09T07:08:50Z Jtneill 10242 Book chapter feedback 2844947 wikitext text/x-wiki Hey! I found this chapter highly interesting, and I love how you've hyperlinked key terminology. It makes the chapter really accessible for someone who is interested in topic but has never studied psychology. The ongoing Maggie case study is also a great learning feature. One suggestion for the 'Emotion suppression' section is currently one incomplete sentence, so it may be worth expanding it with an example or a study. Otherwise , I thought this was a great chapter, well done!! [[User:U3280825|U3280825]] ([[User talk:U3280825|discuss]] • [[Special:Contributions/U3280825|contribs]]) 19:54, 14 October 2026 (UTC) == Feedback == Hi! I really enjoyed reading your book chapter, it was very engaging. I love the layout and it is very reader friendly. My only suggestion is your first figure does not show the picture to readers. Other than this your chapter is very well written! [[User:U3281277|U3281277]] ([[User talk:U3281277|discuss]] • [[Special:Contributions/U3281277|contribs]]) 16:49, 15 October 2026 (UTC) == Resource recommendation == Really nice chapter. One evidence-based idea you might find useful is self-compassion (Neff, 2003), which has been shown to reduce distress after romantic rejection and help regulate emotions. It fits well with the regulation strategies you discussed. NEFF, K. (2003). Self-Compassion: An Alternative Conceptualization of a Healthy Attitude Toward Oneself. ''Self and Identity'', ''2''(2), 85–101. <nowiki>https://doi.org/10.1080/15298860309032</nowiki> [[User:StudentUC2026|StudentUC2026]] ([[User talk:StudentUC2026|discuss]] • [[Special:Contributions/StudentUC2026|contribs]]) 02:32, 23 October 2026 (UTC) <!-- Official book chapter feedback --> {{MEBF/2026 |1= <!-- Overall comments... --> # This is a very good chapter that makes very good use of psychological theory and research to address a real-world phenomenon or problem <!-- Overall - Edit summaries --> # Very good use of [[Motivation and emotion/Wikiversity/Edit summary|edit summaries]] to communicate the changes made in most or all of the main edits <!-- Overall – Citations --> # Excellent use of academic, peer-reviewed citations to support claims <!-- Overall – Word count --> # Under the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]], so there is room to expand # Over the [[Motivation and emotion/Assessment/Chapter#Wordcount|maximum word count]]. Content beyond 4,000 words has been ignored for marking purposes. <!-- Overall – Copy edits --> # For additional feedback, see the following comments and [https://en.wikiversity.org/w/index.php?title=Motivation_and_emotion%2FBook%2F2026%2FRomantic_rejection_and_emotional_response&diff=2844946&oldid=2841237 these copy edits] |2= <!-- Overview – Comments... --> # Very good <!-- Overview – Scenario --> <!-- Overview – Scenario - Description --> # Reasonably good scenario or case study; could be more clear how this relates to romantic rejeection. Attachment styles are explained, so its hard for a reader to know the answer to the question. Consider providing the answer. <!-- Overview – Scenario - Figure --> # Include a relevant image <!-- Overview – Scenario - Feature box --> # The scenario uses an appropriate feature box <!-- Overview – Explains problem --> # Clearly explains the psychological problem or phenomenon <!-- Overview – Focus questions --> # The focus questions are excellent (clear and relevant) |3= <!-- Theory comments... --> <!-- Theory – Breadth --> # Excellent—key theories are very well explained and applied <!-- Theory – Builds on --> # Builds exceptionally well on [[w:|Wikipedia]] articles but not related [[Motivation and emotion/Book|chapters]] by embedding interwiki links for key terms <!-- Theory – Depth --> # Insightful depth is provided about key theory(ies) <!-- Theory – Tables/Figures/Lists --> # Basic use of tables, figures, and/or lists to clearly convey key theoretical information <!-- Theory – Citations --> # In some places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological theory about the topic. <!-- Theory – Examples --> # Excellent use of examples to illustrate theoretical concepts |4= <!-- Research comments... --> <!-- Research – Key findings --> # Excellent review of relevant research # Some emphasis on systematic reviews and/or meta-analyses; more emphasis would be ideal # In some places, the chapter could be strengthened by including more academic, peer-reviewed citations (e.g., see the {{f}} tags). This would help to demonstrate a deeper understanding of relevant psychological science about the topic. <!-- Research – Critical thinking --> # Good [[w:Critical thinking|critical thinking]] about relevant research is evident # [[w:Critical thinking|Critical thinking]] about research could be further evidenced by: ## describing the methodology (e.g., sample, country, measures) in important studies ## considering the strength of relationships ## acknowledging limitations ## pointing out specific critiques/counterarguments ## suggesting ''specific'' directions for future research |5= <!-- Integration comments... --> # Excellent integration between the most relevant theory(ies) and the best research # Insufficient integration with related [[Motivation and emotion/Book|chapters]] |6= <!-- Conclusion comments... --> # Not counted for marking purposes due to the chapter being over the maximum word count |7= <!-- Style comments... --> <!-- Style – Written expression --> # Written expression ## The quality of written expression is very good <!-- Style – Paragraphs --> ## Avoid one sentence paragraphs. Communicate one idea per paragraph using three to five sentences. <!-- Style – Language --> ## Avoid directional phrases such as “as previously mentioned” or “as noted above”, which add little value and can interrupt the flow of writing. Where cross-referencing is necessary, use [[w:Help#Section linking|section links]] to guide readers to the relevant content. ## Reduce use of [[w:weasel words|weasel words]]—they add bulk without improving meaning <!-- Style – Layout --> # Layout ## The chapter is well structured, with major sections using sub-sections ## Use the default heading style (e.g., remove additional numbers, italics, bold, and/or change in font size) ## Include an introductory paragraph before branching into the sub-sections <!-- Style – Grammar --> # Grammar ## The grammar for some sentences could be improved (e.g., see {{g}} tags); consider using a grammar checking tool, [https://www.studiosity.com/students/ Studiosity], and/or peer feedback ## Check and correct use of [https://www.google.com.au/search?q=grammar+that+vs+who that vs. who] ## Use past tense when describing research studies, although implications of findings could be in the present tense ## Improve the clarity and flow of the writing by checking and correcting use of commas. See [https://www.grammarly.com/blog/comma/ Grammarly's guide to using commas]. <!-- Style – Spelling --> # Spelling ## Use [https://www.abc.net.au/education/learn-english/australian-vs-american-spelling/11244196 Australian spelling] (e.g., hypothesize vs. hypothesise; behavior vs. behaviour) <!-- Style – Copy editing --> # Copy editing ## Further [[w:Copy editing|copy editing]] is needed to improve written expression and bring the chapter closer to a professional standard (e.g., correcting punctuation, spelling, grammar, and typographical errors). <!-- Style – APA style --> # APA style ## Use [[w:Serial comma|serial comma]]s[https://www.buzzfeed.com/adamdavis/the-oxford-comma-is-extremely-important-and-everyone-should][https://www.youtube.com/watch?v=gBx8ooDupXY] (also known as the Oxford comma) <!-- Style – APA style - Quotes --> ## Use double (not single) quotation marks "to introduce a word or phrase used ... as slang, or as an invented or coined expression" ([https://apastyle.apa.org/products/publication-manual-7th-edition APA Style 7th ed.], 2020, p. 159) <!-- Style – Figures - Other --> ### Image uploads were removed because of a lack of sufficient/appropriate copyright information; figure numbering needs updating <!-- Style – Tables --> ## Table(s) ### Very well captioned <!-- Style – Tables - Citations --> ### Each Table is referred to at least once within the main text using APA style <!-- Style – Citations --> # Citations use excellent [https://apastyle.apa.org/products/publication-manual-7th-edition APA Style (7th ed.)] # In some places, better use could be made of academic, peer-reviewed citations (e.g., see the {{f}} tags) <!-- Style – References --> ## References use excellent APA style <!-- Feedback responsiveness ---> ## No evidence of responsiveness to feedback on talk page |8= <!-- Learning features comments... --> # Excellent use of learning features <!-- Learning features – Wikipedia embedded links --> # Excellent use of embedded in-text [[m:Help:Interwiki linking|interwiki links]] to Wikipedia articles <!-- Learning features – Wikiversity embedded links --> # Add embedded in-text links to related [[Motivation and emotion/Book|book chapters]]. Embedding in-text links to related book chapters helps to integrate this chapter into the broader book project. <!-- Learning features – Figures, tables, feature boxes, scenarios --> # Insufficient use of figure(s) # Basic use of table(s) # Excellent use of feature box(es) # Excellent use of scenarios, case studies, or examples <!-- Learning features – Quizzes --> # No use of quiz(zes) and/or reflection question(s) <!-- Learning features – See also --> # [[{{PAGENAME}}#See also|See also]] section not counted for marking purposes due to being over the maximum word count <!-- Learning features – External links --> # [[{{PAGENAME}}#External links|External links]] section not counted for marking purposes due to being over the maximum word count |9= <!-- Social contribution comments... --> # ~11 logged, useful, mostly moderate with some /major contributions with [[Motivation and emotion/Assessment/Chapter/Summarising social contributions#How to add direct links to contributions|direct links to evidence]] }} -- [[User:Jtneill|Jtneill]] - <small>[[User talk:Jtneill|Talk]] - [[Special:Contributions/Jtneill|c]]</small> 07:08, 9 November 2026 (UTC) jtswy75sy8w8as8wyjmqdsac2umnw0h 2 332550 2844870 2841461 2026-11-08T15:07:35Z CorraleH 2903442 2844870 wikitext text/x-wiki == Open Research Book - Assessing Wikimedia Research Reproducibility: A Study on Collaborative Practices == === Abstract === Reproducibility underpins scientific credibility. The Wikimedia movement advocates open knowledge, yet the reproducibility of its research outputs has not been evaluated. This project applies a two-phase mixed-methods design. Phase I surveys peer-reviewed publications and documentation (including preprints and white papers) related to Wikimedia, published between 2010 and 2025. A structured reproducibility checklist is applied to a corpus derived from bibliographic databases, generating standardized z-scores for each publication. Phase II uses these scores to draw a stratified random sample, from which corresponding authors are selected for semi-structured interviews on research practices and the influence of their work on the Wikimedia community. Outcomes include a reproducibility package with protocols, data, and code; one peer-reviewed article; and a white paper with recommendations and dissemination strategies. The project engages the Wikimedia research community and connects with funded initiatives such as the bibliometric mapping by Buttliere et al. (2025). It aims to reinforce the epistemological basis of research about the Wikimedia movement. '''Project period:''' July 1, 2026 to June 30, 2027. '''Funding:''' Wikimedia Research Fund 2026. '''Team:''' Lilian Cássia Bórnia Jacob (Universidade de São Paulo, Brazil), Hector Gabriel Corrale de Matos (Universidade de São Paulo, Brazil), Alexandre Hannud Abdo (Centre National de la Recherche Scientifique, France). === What is an Open Research Book? === An Open Research Book is a living, publicly editable document in which a research team records the whole course of a project while it happens, rather than only reporting final results. It works as an open lab notebook and project logbook at the same time: decisions, protocols, versions of instruments, problems found along the way, and deviations from the original plan are written down openly, with dates, so that anyone can follow how the findings were produced. By keeping the research process visible and citable, an Open Research Book supports transparency, reproducibility, and collaboration. Because it lives on a wiki, it keeps a full page history, allows community comments on the talk pages, and can be reused and improved by others. In this project, the book is the public notebook of the team and complements the formal outputs (the article, the dataset, the code, and the white paper). === Notes === ==== Project setup and sourcing ==== * [[/Project log|Project log]] * Corpus and search strategy * Screening decisions * Full-text retrieval ==== Methods and reproducibility ==== * Reproducibility checklist * Annotation pipeline * Statistical analysis ==== Qualitative and interview work ==== * Interview protocol * Qualitative analysis ==== Ethics, protocol, and outputs ==== * Ethics and data management * Deviations from the protocol * Outputs and dissemination * Reading notes and references ==== External links ==== * Preregistration **PRISMA-S * Data management plan * Datasets * Code repository * Meta-Wiki project page bxppy1jskrh74sgouyjz3tp8zj6y493 2844872 2844870 2026-11-08T15:23:25Z CorraleH 2903442 /* Project setup and sourcing */ 2844872 wikitext text/x-wiki == Open Research Book - Assessing Wikimedia Research Reproducibility: A Study on Collaborative Practices == === Abstract === Reproducibility underpins scientific credibility. The Wikimedia movement advocates open knowledge, yet the reproducibility of its research outputs has not been evaluated. This project applies a two-phase mixed-methods design. Phase I surveys peer-reviewed publications and documentation (including preprints and white papers) related to Wikimedia, published between 2010 and 2025. A structured reproducibility checklist is applied to a corpus derived from bibliographic databases, generating standardized z-scores for each publication. Phase II uses these scores to draw a stratified random sample, from which corresponding authors are selected for semi-structured interviews on research practices and the influence of their work on the Wikimedia community. Outcomes include a reproducibility package with protocols, data, and code; one peer-reviewed article; and a white paper with recommendations and dissemination strategies. The project engages the Wikimedia research community and connects with funded initiatives such as the bibliometric mapping by Buttliere et al. (2025). It aims to reinforce the epistemological basis of research about the Wikimedia movement. '''Project period:''' July 1, 2026 to June 30, 2027. '''Funding:''' Wikimedia Research Fund 2026. '''Team:''' Lilian Cássia Bórnia Jacob (Universidade de São Paulo, Brazil), Hector Gabriel Corrale de Matos (Universidade de São Paulo, Brazil), Alexandre Hannud Abdo (Centre National de la Recherche Scientifique, France). === What is an Open Research Book? === An Open Research Book is a living, publicly editable document in which a research team records the whole course of a project while it happens, rather than only reporting final results. It works as an open lab notebook and project logbook at the same time: decisions, protocols, versions of instruments, problems found along the way, and deviations from the original plan are written down openly, with dates, so that anyone can follow how the findings were produced. By keeping the research process visible and citable, an Open Research Book supports transparency, reproducibility, and collaboration. Because it lives on a wiki, it keeps a full page history, allows community comments on the talk pages, and can be reused and improved by others. In this project, the book is the public notebook of the team and complements the formal outputs (the article, the dataset, the code, and the white paper). === Notes === ==== Project setup and sourcing ==== * [[/Project log|Project log]] * [[/Corpus and search strategy|Corpus and search strategy]] * Screening decisions * Full-text retrieval ==== Methods and reproducibility ==== * Reproducibility checklist * Annotation pipeline * Statistical analysis ==== Qualitative and interview work ==== * Interview protocol * Qualitative analysis ==== Ethics, protocol, and outputs ==== * Ethics and data management * Deviations from the protocol * Outputs and dissemination * Reading notes and references ==== External links ==== * Preregistration **PRISMA-S * Data management plan * Datasets * Code repository * Meta-Wiki project page ieikditory7e9x2yk2lat5zk10rvejl 2844873 2844872 2026-11-08T15:26:16Z CorraleH 2903442 /* External links */ 2844873 wikitext text/x-wiki == Open Research Book - Assessing Wikimedia Research Reproducibility: A Study on Collaborative Practices == === Abstract === Reproducibility underpins scientific credibility. The Wikimedia movement advocates open knowledge, yet the reproducibility of its research outputs has not been evaluated. This project applies a two-phase mixed-methods design. Phase I surveys peer-reviewed publications and documentation (including preprints and white papers) related to Wikimedia, published between 2010 and 2025. A structured reproducibility checklist is applied to a corpus derived from bibliographic databases, generating standardized z-scores for each publication. Phase II uses these scores to draw a stratified random sample, from which corresponding authors are selected for semi-structured interviews on research practices and the influence of their work on the Wikimedia community. Outcomes include a reproducibility package with protocols, data, and code; one peer-reviewed article; and a white paper with recommendations and dissemination strategies. The project engages the Wikimedia research community and connects with funded initiatives such as the bibliometric mapping by Buttliere et al. (2025). It aims to reinforce the epistemological basis of research about the Wikimedia movement. '''Project period:''' July 1, 2026 to June 30, 2027. '''Funding:''' Wikimedia Research Fund 2026. '''Team:''' Lilian Cássia Bórnia Jacob (Universidade de São Paulo, Brazil), Hector Gabriel Corrale de Matos (Universidade de São Paulo, Brazil), Alexandre Hannud Abdo (Centre National de la Recherche Scientifique, France). === What is an Open Research Book? === An Open Research Book is a living, publicly editable document in which a research team records the whole course of a project while it happens, rather than only reporting final results. It works as an open lab notebook and project logbook at the same time: decisions, protocols, versions of instruments, problems found along the way, and deviations from the original plan are written down openly, with dates, so that anyone can follow how the findings were produced. By keeping the research process visible and citable, an Open Research Book supports transparency, reproducibility, and collaboration. Because it lives on a wiki, it keeps a full page history, allows community comments on the talk pages, and can be reused and improved by others. In this project, the book is the public notebook of the team and complements the formal outputs (the article, the dataset, the code, and the white paper). === Notes === ==== Project setup and sourcing ==== * [[/Project log|Project log]] * [[/Corpus and search strategy|Corpus and search strategy]] * Screening decisions * Full-text retrieval ==== Methods and reproducibility ==== * Reproducibility checklist * Annotation pipeline * Statistical analysis ==== Qualitative and interview work ==== * Interview protocol * Qualitative analysis ==== Ethics, protocol, and outputs ==== * Ethics and data management * Deviations from the protocol * Outputs and dissemination * Reading notes and references ==== External links ==== * Preregistration **PRISMA-S * Data management plan * Datasets * Code repository *[[meta:Research:Assessing_Wikimedia_Research_Reproducibility:_A_Study_on_Collaborative_Practices|Meta-Wiki project page]] * [[meta:Grants:Programs/Wikimedia_Research_Fund/Assessing_Wikimedia_Research_Reproducibility:A_Study_on_Collaborative_Practices|WMF Grant application]] 0z2q2yggpo6wm3hva12lrhwmxgbhj6x 0 332595 2844937 2844426 2026-11-09T06:24:39Z Wb525 3112992 /* Precession term */ 2844937 wikitext text/x-wiki {{Research project}} ''Original research project by Willy Bohane — UG.NUG.'' == All the texts in this presentation == [[Cosmology: UG.NUG an Observation-Based Model|UG.NUG]] [[Cosmology: UG.NUG an Observation-Based Model/ΛCDM|ΛCDM]] [[Cosmology: UG.NUG an Observation-Based Model/Cosmic Time|Cosmic Time]] [[Cosmology: UG.NUG an Observation-Based Model/the Mass Imbroglio|the Mass Imbroglio]] [[Cosmology: UG.NUG an Observation-Based Model/the CMB|of the CMB]] [[Cosmology: UG.NUG an Observation-Based Model/the GRID|of the GRID]] [[Cosmology: UG.NUG an Observation-Based Model/Gravity|of Gravity]] [[Cosmology: UG.NUG an Observation-Based Model/Black Holes|of Black Holes]] = Current Definition = In encyclopedias, one cannot really say that time is defined, and when it is, it is closer to a sequence of events than to the measurement of time — its chronometry. A year, a day, a minute… This chronometry is only possible relative to precise references. References that are not other than the circadian pace of day and night that impact and rhythm the life of living beings. References that now exist throughout the universe, since the cesium atom is used to measure the second — even though its origin remains a human convention and the second itself expresses a duration, not human chronometric time. So one could live on Mars using the same time we use on the Earth by convention. A watch, based on cesium pace, could tell him when to stop working or watch TV. The only absolute necessity would be to keep contact with Earth in order to check, from time to time if their time systems are correctly synchronized to the circadian time. It is then evident that it is technically realizable as long as a logical limit of communication delay is not reached — delay that could affect the precision of the synchronization. This shows that this little interplanetary arrangement is not a universal solution and that still, cosmic time does not exist. We can add that time remains a human interpretation and chronometry of duration — and that, without Man, time exists nowhere. Not even on Earth. = Succession = What does exist, however, is '''Succession.''' This sequence of events gives the idea of past and future. A glass that breaks cannot reassemble itself. Indeed, once it has broken, we can say: it was intact (past), and now (present/future) it is shattered. This succession gives the impression of time passing, but without chronometry it is not the useful time indicated by our watches; it is simply a '''Succession''' of events. The confusion is easy, but the difference is immense. Our prehistoric ancestors saw that days followed one another, that the dead did not wake up, that water flowed in one direction in streams and rivers. But they had no watches. They did not measure time. They had no appointments at 3:00 p.m. At best, they could agree to meet at sunrise or sunset — nothing more. And it is precisely this reference — '''sunrise or sunset''' — actually '''the circadian periodicity,''' that makes time measurement possible. It seems far from inconsequential that the word "precession" — if it were the antonym of succession — does not exist. This is a kind of confirmation that such a movement has never been needed to explain the universe. It is not proof of anything, but we must admit that it is quite interesting. = the Circadian Periodicity = What we wear on our wrist is the calculation of this periodicity, divided into units of measurement: hours, minutes, seconds. Time zones are interpretations of this periodicity, based on the dance of the Sun and Earth for each latitude. People wake with the day in America, and in France as well — at the same local time, '''but not at the same moment'''. Universal time therefore does not exist. On the contrary, it exists only for this pin‑head called Earth, hidden among trillions of football fields. Worse still, it exists only for the humans who live on it. Animals do not care. Time zones are the best evidence of the circadian periodicity as they measure the sleep and awake time of humans all around the world. = the Misundertanding = Chronometric time is a key value for many physical parameters and equations. It is the basis of acceleration and velocity, which in turn allow us to calculate force, thrust, and so on. Even Einstein misunderstood this, naming his concept ''spacetime'', whereas its true name should have been closer to ''local-space‑time'' since time exists only for humans, locally, and not in the universe.   ΛCDM itself, when it calculates the age of the universe as 13.7 billion years, speaks of years that did not exist before the appearance of the Earth and the Sun. It obviously gives an idea of duration in a human's mind but says nothing about the real age of the universe. = The Light Years = Since distances are expressed in kilometres travelled by light in a year, we assume that cosmic distances are a question and a function of time. This is why this passage is of immense importance for the understanding of cosmology — or rather, for its misunderstanding, because this mistake calls the whole of it into question. The light-year is a human mind unit. The same is true of the speed of light. It is usually presented as a universal constant — 299,792,458 metres per second. But the metre and the second are human units. The second is defined by the circadian periodicity of life on Earth. The metre is defined by the distance light travels in 1/299,792,458 of a second. Each unit refers back to the other, and both refer back to the Earth and its humans. The speed of light is therefore not a constant of the universe, but a human convention — a circular one. '''Nothing is measurable in the universe without a human or any other entity's reference.''' o8o8lajdpt6kn1hvgd9lf1wzdjpu6yd 0 332786 2844935 2844856 2026-11-09T06:21:26Z Wb525 3112992 undifferentiated / elementary 2844935 wikitext text/x-wiki {{Research project}} Original research project by Willy Bohane — UG.NUG. https://doi.org/10.5281/zenodo.20644064 == All the texts in this presentation == [[Cosmology: UG.NUG an Observation-Based Model|UG.NUG]] [[Cosmology: UG.NUG an Observation-Based Model/ΛCDM|ΛCDM]] [[Cosmology: UG.NUG an Observation-Based Model/Cosmic Time|Cosmic Time]] [[Cosmology: UG.NUG an Observation-Based Model/the Mass Imbroglio|the Mass Imbroglio]] [[Cosmology: UG.NUG an Observation-Based Model/the CMB|of the CMB]] [[Cosmology: UG.NUG an Observation-Based Model/the GRID|of the GRID]] [[Cosmology: UG.NUG an Observation-Based Model/Gravity|of Gravity]] [[Cosmology: UG.NUG an Observation-Based Model/Black Holes|of Black Holes]] = Introduction = This article presents a reading of the Universe that differs in every respect from the existing model. The latter contains a false start which, for reasons explained in the dedicated article on [[Cosmology: UG.NUG an Observation-Based Model/ΛCDM|ΛCDM]], renders it null and void from the very first millisecond of its narrative: the Singularity. Before reading this detailed text, whose links to technical articles support and further develop the arguments presented, readers can consult a simplified [https://www.wbohane.com/BLOG/!three_point_universe.aspx three-point diagram] offering an overview of the proposed simplicity of the Universe. = State of Play = First, it is important to understand that cosmology, in its interpretative function, is not an exact science. As its name indicates, it means, in Greek, ''the study of the world'' — and therefore, by extension, its origin, its structure, its evolution, its content, and its future. We also have a duty never to forget that cosmology was born as a branch of metaphysics. This should remind us that mathematics must remain a means of understanding the Universe, not a substitute for it. Rather than building elaborate theoretical structures and continually adjusting them to accommodate observations, it would be far more sensible to seek a description that reflects the universe as it actually is. The purpose of cosmology should not be to make reality fit our mathematics, but to make our mathematics serve reality. This is why interpretative cosmology resembles a religion more than it does a science. As with religion, everybody can say anything, everybody can believe anything, everybody can make anyone believe anything. Humanity is divided into many creeds, and so is cosmology. This is why the following list of flaws is possible, especially where science is subjected to the rules of a free market place. '''[[Cosmology: UG.NUG an Observation-Based Model/ΛCDM|The long long list of ΛCDM flaws]]''' = the Natural Best-Way Principle = == definition == The Best-Way is the optimal solution attainable at a given stage of a process. It represents the point beyond which no further improvement is possible under the existing conditions. However, it is never necessarily permanent, as accumulated experience and evolving possibilities may eventually reveal a better way. == in Practice == In accordance with the principle of parsimony, observation, reading and reflection should be the first instincts to guide us when we look up at the sky and ask ourselves what the Universe is. But we must proceed with due respect for our own nature as human beings, confronted with the immensity of a habitat we did not choose, which brings us into existence, sustains us, and ultimately eliminates us without even noticing. In this sense, cosmology has less to do with technology than with philosophy, the mother of all sciences. Parsimony is not merely a rule of thought formulated by a philosopher. Long before Occam, it was already at work in nature. Water flowing downhill follows the paths available to it, overcoming the constraints of its environment while dissipating its available energy. This natural economy also brings to mind Darwin's principle of natural selection: forms that are better adapted to their environment are more likely to survive and perpetuate themselves. Nature does not necessarily favour simplicity, but it does not grant lasting advantages to unnecessary expenditure either. This should be a lesson for every human undertaking. Any project, theory, process or model that accumulates unnecessary complexity, without gaining anything in return, eventually exposes itself to being outperformed and replaced. An inadequate solution may nevertheless survive temporarily, simply because no better alternative is yet available. But it cannot indefinitely withstand the progress of knowledge and technology, which will eventually reveal and make possible a better way of achieving the same goal. When human beings, through the ΛCDM model, presume to decide when the Universe began and how it began, they brazenly violate the modesty and humility that should be incumbent upon them. They do so much as the authors of the biblical creation narrative did — distant predecessors whose audacity might be forgiven, but whose example is no longer intellectually acceptable in the twenty-first century. The issue here is not even to revisit the invalidity of such a conjecture, which is discussed at length in the list of flaws. Rather, it is to ask by what right the model's architects permitted themselves to make such an extraordinary claim in the first place. From that moment on, the claim becomes null and void, without further appeal. = the Universe = So, what does observation tell us when we look up at the sky? First and foremost, it tells us that the Universe exists, that it was already here before us. Our age and our experience also tell us that, as human beings, we are merely passengers, temporary workers, and mortals in waiting, and that whatever we do, the Universe will always be stronger than we are. Consequently, the only natural and parsimonious conclusion we can draw from looking at the sky is that the Universe exists, that it did not ask us to exist, and that it has never told us when it began, how it began, or why it began. From this starting point, we can say, without doubt, without prejudice, without invention, and, quite simply, without making things up, that what we see around us is the Universe; that it is the only thing that exists as far as we are concerned; that it does not know human clock-measured time; and that it is absolutely impossible for us to say anything more about it. Pure logic would therefore suggest that we consider ourselves inhabitants of a stationary Universe, one that would have absolutely no need to expand. The initial observation does not impose expansion upon us. A stationary universe therefore constitutes the most parsimonious starting point. On the one hand, this means not inventing an improbable birth date; on the other, it means not inventing an equally improbable expansive Big Bang. However, with our eyes fixed on the sky, especially at night, we see the Moon. And we are entitled to wonder why it does not fall on our heads, even before knowing about gravity or having the slightest idea of its existence. The natural reflex would therefore be to consider the concept of the Apeiron — an undefined, omnipresent substrate — or Aristotle's concept of Ether, or Faraday's idea of a "something" that might sustain celestial objects. Although these concepts are not entirely identical, they all point towards the same fundamental intuition: the possibility of a "Something" underlying the visible world. This may well be one of humanity's oldest intellectual reflexes. It comes naturally to mind whenever something appears to hang in the void, even during a Houdini performance. Something must be holding it, surely! And at this point, one might begin to think that the Universe is not what we see, but rather what we do not see: that what is visible emerges from a fertile, invisible substrate that fills the entire Universe. This would be a very concrete and believable image if all visible celestial objects appeared to be suspended in the void — suspended, yet held in the embrace of that same substrate, which prevents everything from collapsing. It is much like the air that fills the space on Earth. When the plant emerges from the ground, the air surrounds the plant, continues to envelop it, nourish it, and influence its nature. = The CMB = If we remain within this parsimonious perspective, which so far has required no invention, no additions, and no patches, it is easy to see why a sense of serenity might take hold of our minds. We have already saved ourselves quite a lot: the singularity and its strangeness, the improbable Big Bang, expansion and the many complications it brings in its wake… But be patient. We are about to do even better. Because when Penzias and Wilson discovered the cosmic microwave background radiation, nothing in that discovery compelled us to think of a fossil. The idea of a distant past was not even a necessary intellectual or cosmological option within this line of thought. Why go looking for a fossil, and where would it have come from? No, the question would not even arise. We would instead think of that substrate — the very one we had already invoked to explain why the Moon does not fall on our heads — which might now turn out to be noisy as well. Hardly a reason to spoil the party, this radiation would be the living confirmation of what humanity had intuited for 2,700 years: a "Something" that sustains "Everything." So what better response than to shout: "Bingo!" Since none of the observed properties of the [[Cosmology: UG.NUG an Observation-Based Model/the CMB|CMB]] contradicts this possibility, it would be only fair, and consistent with the principle of parsimony, to acknowledge that this interpretation is far simpler and more appealing than the intricate story of a cosmic fossil, its journey across billions of years, its puzzling temperature, and all the complications that come with it. = the Arrow of Emergence = The glass' message is one of the very few hints the universe deigned to offer us before its long nap. What it whispers if it slips from our hands and, by misfortune, the floor is tiled rather than carpeted: it shatters. And if we read the universe simply, we catch this message that expresses the irreversible Cosmic Order: the one that prevents the glass from reassembling, the one that prevents events from denying their own existence. Thus, the universe gives us the direction from past to future, what current physics commonly calls the Arrow of Time. It is striking: it gives us the Arrow of Time, but not time itself. The current name, Arrow of Time, is not really appropriate, since it is not “time” in the chronometric sense. It is rather, as explained earlier, a pre‑cosmic Order that governs everything, the universe included. Yes, this is an inescapable consequence of a careful reading of the universe. This succession order is of primary importance in the UG.NUG reading, but also in the ΛCDM, which — it seems — has not given it the place it deserves. In the [[Cosmology: UG.NUG an Observation-Based Model/ΛCDM|ΛCDM]], one observes that the universe ceased its creative activity only once its work was complete. One day, it emerged from an unknown state — the term ''Big Bang'', which everyone knows, usually refers to this event — and then particles appeared, followed by atoms, stars, galaxies… Since then, nothing is created, nothing is lost, everything transforms, as Lavoisier would say. What matters here is not the validity of this narrative, but the Succession  of things: this natural succession of phases is precisely the Succession  in question. And that is why we have renamed this arrow the Arrow of Emergence. The misunderstanding dissolves, and the meaning becomes clearer: Succession  of emergences versus time‑keeping. The Arrow of Emergence therefore indisputably precedes the universe. It’s new, fresh off the shelf, ready‑to‑wear. This can mean several things: * the arrow was there, and that’s all. We accept the universe and take the arrow as a bonus, * the arrow was there, and therefore the universe is governed by something we do not know, * the arrow was there, and therefore our universe is part of a series of universes, * the arrow was there, and therefore we are free to consider any interpretation. In short, it mainly means that the Arrow of Emergence is particularly important — especially for what follows. = The GRID = Since CMB is the name given to the discovery, it seems fair to rename it according to its cosmological function. Faraday deserves his “something,” and we have chosen [[Cosmology: UG.NUG an Observation-Based Model/the GRID|GRID]], which stands for Global Reference in Dynamics. In UG.NUG, the model presented in this paper, the [[Cosmology: UG.NUG an Observation-Based Model/the GRID|GRID]] is ''le clou du spectacle'', as the French would say — the highlight of the entire show. It is the key element that dissolves most of the paradoxes of ΛCDM in such a simple way that it seems almost impossible to have overlooked it. In other words, without the GRID, UG.NUG would be no more interesting than any other model. = UG = Apart from its resemblance to the exclamation of a prehistoric man, this name carries a very important cosmological meaning. What we call geometry refers to the shape or size of an individual object, properties that matter in its interactions with reality. Geometry begins above the level of chemistry. UG stands for the French '''''Uniformité Genrée''''' (Categorical Uniformity). We coined this term to describe a phenomenon whose significance has gone unnoticed. In short, everything produced by the Universe in its earliest stages — particles, nuclei, and so on — belongs to this regime, in which objects possess no geometry. They have no individuality, no history, and no variation. This uniformity is the hidden foundation of everything: the silent order governing the birth of the Universe. For now, let us simply understand that, in this model, the world of the very small — below the atomic level — has no geometry, even though some textbooks may suggest otherwise. = NUG = NUG stands for the French '''Non-Uniformité Genrée''' (Categorical Non-Uniformity). It represents everything that possesses geometry and individuality: stars, planets, meteors, and, of course, everything that derives from them — humans, artifacts, flora, and fauna. No two pebbles are alike, nor are any two trees. Individuality increases with complexity. The transition from UG to NUG occurs through the assembly of atoms and molecules, the underlying mechanism of which remains unknown. NUG is the third and final phase in the emergence of an object. Since humans, along with their clocks and measuring instruments, belong to NUG, the time measured by our wristwatches is also a NUG phenomenon. In this model, measurable time exists only where geometry and individuality exist. = UG.NUG = UG.NUG is the name of this model. It encompasses the two regimes that govern the entire Universe. As we shall see, NUG — and therefore geometry — emerges later than UG. Once it appears, however, it becomes an integral part of the Three Point Universe, a concise schematic representation of the UG.NUG model. NUG encompasses all objects, including the Moon and the other celestial bodies mentioned earlier, which, fortunately, do not fall on our heads. == Redshift == The UG.NUG reading understands that geometry is not a starting point, but a secondary level of organization, appearing only after UG. This single shift is enough to dissolve almost all cosmological problems of the ΛCDM. Thus, the universe is not the product of a geometric explosion, but is grounded in an elementary background. Geometry appears only when objects cease to be identical. This conceptual reversal eliminates in one stroke the paradoxes related to the origin of space, its shape, its homogeneity, or its flatness. One no longer tries to explain why geometry is already there. It is not an initial condition, but appears naturally, carried by the Arrow of Emergence, and stabilizes thanks to the GRID. The image of a fabric tube being inflated illustrates this perfectly. The tube already exists, but it is not yet deployed. Near the opening, the fabric is inflated; farther away, it seems to inflate progressively; in the distance, it is still flat. For an observer inside, this creates the illusion of expansion, then accelerated expansion, even though it is only the progressive realization of the structure. The distant regions appear to recede because they are not yet realized, not because they are moving. This inversion of perspective dissolves the very idea of cosmic expansion, inflation, an initial singularity, or dark energy. The spectroscopic observations and measurements themselves are not being disputed. The observed redshifts, the recorded spectra, and the data themselves remain unchanged. What UG.NUG challenges is the interpretation placed upon them: that redshift necessarily indicates recession, and that this recession necessarily means that space is expanding. The issue, therefore, is not the validity of the observations, but the assumptions through which they are interpreted. The same measurements may point to a different reading of the Universe. There is, however, a further question concerning the validity of the measurements themselves. As discussed in the paper on Cosmic Time, if the Universe has no intrinsic time, the very notion of measuring cosmic durations or assigning chronological ages to distant events becomes questionable. Such measurements rely on a chronometric framework whose applicability UG.NUG challenges. This raises a separate and much broader issue, which cannot be addressed here without taking us away from the subject of redshift. = the Genesis Phases = Now that the framework has been established, and we have seen that our universe is neither outlandish nor fundamentally different from the one we know, and that it is not threatened by our models, however incongruous they may be, we can begin to imagine what might actually have happened to produce the spectacle before our eyes. For this section, then, a little imagination is indeed required. Yet, for reasons of pure logic, the sequence you are about to discover is hardly surprising. The principle of parsimony remains our guide. Water has always flowed, and will always flow, along the paths best suited to its passage. This natural law, which is suspected to have inspired William of Ockham in formulating his principle, is far from trivial when attempting to reconstruct an event such as the emergence of the universe through a virtual model. We shall therefore continue to refrain from introducing artificial devices into the natural stages described below. = the First Phase = Strictly speaking, this is not a phase at all. It is included here to make clear that everything begins with the omnipresence of the universe. This phase never began, because it is our sole reality. Nothing else exists. This omnipresence is inferred from, and embodied in, the omnipresent GRID, which belongs to the UG regime, where objects inaccessible to our senses have no history, variation, or individuality. We do not know what it is made of. Nevertheless, it is logical to suppose that it contains the codes of the perceivable universe: the non-geometric component commonly encountered at the depths of matter and described by quantum mechanics, including elementary particles and atomic nuclei. For human beings, such a configuration borders on metaphysics. Our cognitive faculties are not designed to grasp invisible, non-geometric entities that carry information, almost like ghosts. We can invent ghosts, but we cannot manage them. According to the standard cosmological model, this radiation was released approximately 380,000 years after the Big Bang, hence its designation as fossil radiation. Such dating has no meaning within the present model, since chronometric time, as explained earlier, does not exist at the fundamental level of the universe. The quantum effervescence associated with the emergence of the GRID is held together by a fundamental UG energy: a pre-geometric substrate that makes emergence possible. This energy may correspond to the unique energy of the BBP, subsequently differentiated into the electromagnetic, weak, and strong interactions, the latter ensuring nuclear cohesion. These interactions then mysteriously disappear from the broader cosmological narrative. The persistence of the GRID explains its presence in every atom. Whatever an atom may eventually become, it retains this universal imprint. When an atom is destroyed, its particles are not necessarily destroyed with it: they return silently to the elementary reservoir of the GRID. Quantum particles cannot be manipulated directly in their fundamental nature; they emanate from the original GRID. This is a personal assertion, but not an entirely baseless one. As explained in The Fear of the Unexplainable, the dominant mindset refuses to accept that the unexplainable might be fundamental. Everything must be physical — except when it is convenient to invoke something more elusive, as when fundamental energy is called upon to explain atomic cohesion. This double standard exposes what should be regarded as a lack of logic in the BBP. This is why CERN is unlikely ever to obtain the results it expects. These particles will never reveal what they truly are. Attempting to reach the UG side of the universe using NUG instruments is like asking a newborn to intervene in the device that brought it into existence. The limitations become apparent immediately. The atomic bomb has already shown, with tragic consequences, what can happen when humanity interferes too directly with the elements of the GRID. Einstein was right to reject the idea that “God plays dice.” His “God” — nature, the universe itself — is present in every object. He did not believe that quantum mechanics had appeared in matter by chance. Yet this is precisely how Bohr and Heisenberg interpreted it: they treated quantum mechanics as a contingent curiosity rather than as the signature of something still unknown. = the Second Phase = Once the presence of the underlying “carpet” containing the codes has been established, it becomes plausible that primary objects — atoms and simple molecules — begin to form. These are the first objects to possess geometry, yet all objects of a given kind remain identical to one another. Any attempt to determine the precise beginning and end of this phase through elaborate calculations would be highly speculative. The immaterial effervescence persists, but it is now accompanied by objects that require time to assemble. In parallel, the fundamental energy of the GRID becomes involved in maintaining the cohesion of these new atomic structures. This cohesive role requires it to manifest properties that were previously unnecessary: the strong interaction, which binds the constituents of atomic nuclei together; the weak interaction, whose role is more secondary in this context; and the electromagnetic interaction, which governs exchanges between charged particles. One energy, then, with multiple manifestations — always present, always active. In this model, it replaces the various concepts invoked by the BBP to describe primordial energy and its effects: vacuum energy, dark energy, the cosmological constant, and quantum fluctuations. These become different labels for what the model interprets as a single primordial presence. At this level, deduction is more reliable than equations. When atomic nuclei absorb part of the primordial energy and convert it into binding energy or other forms of energy associated with their structure, they clearly do not absorb the entire substrate that sustains them. Like leaves floating on a pond, organised structures can appear without eliminating the medium in which they exist. The primordial energy continues to sustain the whole, even when part of its flow is redirected towards cohesion. Atoms are assemblies of ghosts, and all atoms of a given kind appear identical. What lies at their heart is non-geometric and cannot be observed directly. Applied physics detects only measurable effects — energies, transitions, and interactions — never the intrinsic nature of the particles themselves. Conversely, the BBP assigns geometric labels to entities that are inferred from non-geometric experimental results: spin, charge, isospin, quantum numbers, and so on. Collisions produce deposited energies, momenta, angles, jets, resonances, and statistical peaks. From these data, the BBP constructs its picture of elementary particles. This conceptual shift is rarely acknowledged. Despite the absence of directly geometric data at the fundamental level, the BBP continues to construct its own universe in order to preserve what may be regarded as a sterile mathematical edifice. The second phase is the bridge between the inaccessible and the modifiable, between UG and NUG, between the GRID and geometry. = the Third Phase = All remaining objects — stars, planets, galaxies, and everything that derives from them — emerge according to their order of formation, depending on the availability and completeness of the preceding stages for each object individually. This is where uniformity ends and individuality begins. No precise dating is possible within the present model. This phase represents the culmination of the process: the world that emerges from UG, the world we see, touch, hear, smell, and taste. Once UG has reached maturity, complex forms, interactions, and histories become possible. The universe enters the NUG regime. NUG encompasses: * Stars * Planets * Chemistry * Biology * Perception Everything we experience is the final geometry of a pre-geometric reality. Pre-geometric also means pre-volumetric. The GRID — UG — is both pre-geometric and pre-volumetric. Geometry begins above the atomic level, and individuality emerges with complexity. The GRID has no visible form. It manifests itself through the infinitesimal temperature variations observed in the CMB in every direction, through gravity on Earth, and through magnetic fields. It is an invisible presence that precedes the emergence of volumetric structures. In this model, geometry and volume emerge from UG without requiring expansion, unlike the BBP, which postulates an initial singularity followed by the expansion of the metric. Our interpretation is straightforward: * '''No singularity:''' the universe is already extended in the form of the GRID. * '''No infinities:''' emergence follows an ordered sequence, from Phase 1 through Phase 2 to Phase 3. * '''No paradox:''' geometry, or NUG, emerges from UG without requiring expansion. The GRID never disappears. It permeates every atom in every object. It is present throughout our world in the form of quantum mechanics, whose rules, according to this model, differ radically from those commonly accepted. Using a scanning tunnelling microscope (STM), it is possible to distinguish individual atoms and observe their arrangement. Don Eigler demonstrated this in 1989 by positioning xenon atoms on a nickel surface to spell out the letters IBM. Beyond the atomic scale, the gap in scale becomes immense. Atoms are approximately a nanometre across, whereas the characteristic scale of their constituent particles is around a femtometre — roughly one millionth of a nanometre. No elementary particle has been observed directly in the sense of being imaged as a tiny object with a visible surface. Instead, experiments detect traces and measurable effects from which the properties of particles are inferred. The process is therefore highly indirect. Every fragment of matter carries within it an irreducible part of the universe's deepest mystery, together with the codes from which geometry emerges. = Conceptual Consequences = The problems of the ΛCDM are not independent: they naturally group into three families, all stemming from the same implicit assumption — that the universe is fundamentally geometric. By changing this starting point, these difficulties cease to be enigmas. They become the expected consequences of an inadequate reading. The three blocks that follow present these families of problems and show how UG.NUG reading dissolves them without additions, without corrections, simply by restoring the natural Succession of emergence. == for Cosmology == Dark matter — Dark energy — Cosmological constant — Horizon — Flatness — Homogeneity — Origin of geometry — Big Bang — Expansion — Large‑scale structure The UG.NUG reading understands that geometry is not a starting point, but a secondary level of organization, appearing only after UG. This single shift is enough to dissolve almost all cosmological problems of the ΛCDM. Thus, the universe does not begin with a geometric explosion, but with an elementary background. Geometry appears only when objects cease to be identical. This conceptual reversal eliminates in one stroke the paradoxes related to the origin of space, its shape, its homogeneity, or its flatness. One no longer tries to explain why geometry is already there. It is not there at the beginning. It appears naturally, carried by the Arrow of Emergence, and stabilizes thanks to the GRID. The image of a fabric tube being inflated illustrates this perfectly. The tube already exists, but it is not yet deployed. Near the opening, the fabric is inflated; farther away, it seems to inflate progressively; in the distance, it is still flat. For an observer inside, this creates the illusion of expansion, then accelerated expansion, even though it is only the progressive realization of the structure. The distant regions appear to recede because they are not yet realized, not because they are moving. This inversion of perspective dissolves the very idea of cosmic expansion, inflation, an initial singularity, or dark energy. In this reading, the great cosmological enigmas cease to be anomalies. * Dark matter is no longer an invisible substance added to fix equations, but the consequence of applying a geometric interpretation to a phenomenon that is not geometric. * Dark energy is no longer a mysterious force pushing the universe to expand, but the effect of a secondary geometry misread as dynamic when it is simply structural. * The horizon problem disappears because homogeneity does not need to be transmitted: it is inherited from UG, where everything is identical. * The flatness problem vanishes because geometry is not a fragile structure requiring fine‑tuning, but a stable organization imposed by the GRID. In the UG.NUG reading, geometry is not fundamental but secondary, emergent. By changing the starting point, one does not correct anomalies: one dissolves them. The universe was never incoherent. The interpretation was. == for Quantum Physics   == Measurement - Decoherence - Superposition - Classicality - Quantum gravity - Particle identity - Non‑locality - Hidden variables - Wave‑particle duality - Indeterminacy - Absence of trajectory Quantum physics accumulates paradoxes because it tries to describe a non‑geometric regime using geometric tools. It applies notions of shape, position, trajectory, or mass to objects that possess none of these. In UG.NUG reading, first‑wave particles belong to the UG regime: they are inaccessible, elementary, without form, without variation, without geometry. They are not tiny objects but non‑identifiable pre‑geometric entities.   In this reading, the measurement problem disappears. * There is no wave‑packet collapse, only the transition from a UG state to a NUG interaction — that is, the appearance of a geometric imprint. * Decoherence is no longer a mysterious mechanism, but is simply the incompatibility between a non‑geometric state and a geometric environment. * Superposition is not a magical phenomenon, but the natural behavior of objects that have neither shape nor position. * Classicality needs no explanation: it appears as soon as objects acquire geometry — that is, in the second phase, the primordial one. * Quantum gravity ceases to be a meaningful objective, because there is nothing to quantize. * Gravity is not a fundamental force but the static reaction of the GRID, a purely geometric phenomenon. * Non‑locality is no longer a mystery: in a non‑geometric regime, the notion of distance has no meaning. * Hidden variables have no place: there is nothing to hide in a regime without internal structure. Thus, all quantum paradoxes arise from a single mistake: trying to apply NUG tools to UG. The paradoxes vanish as soon as we stop demanding that UG behave like a geometric world. Quantum mechanics is the universe’s signature within every atom of matter, and the keeper of the code for the geometry of the emergent, perceivable forms that make up our world. That said, where we hope this reading of the universe can serve as a model is in a radical shift in how we treat the information obtained through the manipulation and analysis of particles. In fact, the investigations concerning them can be counted on the fingers of one hand: <nowiki>:</nowiki> * energy levels through spectrometry, * transition probabilities in lasers, * electronic structures via STM, * conduction bands in solid‑state physics, * bound states in quantum chemistry. Yet these data, as precise and rich as they are, are systematically and arbitrarily transformed into geometric forms: orbitals, positions, bands, crystal lattices… as if nature suddenly became classical the moment we look at it. But none of this has ever been observed. The size of particles, their wave‑particle duality, and above all the very principle of quantum mechanics — where everything is probabilities, superpositions, and wave functions — should forbid this geometric illusion. Why, then, this persistent habit of hiding raw data beneath familiar but false representations? Why prefer reassuring visual models over a clear presentation of investigative methods and probabilistic results? Quantum mechanics has taught us that reality is not a neat drawing of well‑traced orbits, but a cloud of probabilities in constant evolution. Yet we continue to teach, publish, and design technologies based on geometric diagrams that are nothing more than convenient metaphors — or even lies by omission. The problem is not only scientific; it is epistemological. By over‑geometrizing, we reduce quantum complexity to a classical caricature and deprive researchers — and the public — of an honest understanding of what particles and their interactions truly are. Atomic orbitals are not physical objects occupying geometrically defined regions of space. They are mathematical representations of quantum states. So why not fully embrace quantum strangeness? Why not present the data as they are: probability distributions, complex amplitudes, entangled states? Science has a duty to tell the truth, even when it is unsettling. And the truth, here, is that the quantum world has nothing geometric about it — at least not in the classical sense we impose on it. Perhaps it is time to break with this tradition and finally show the real face of matter: not a collection of localized objects, but a network of possibilities in perpetual fluctuation, where geometry is only a shadow cast by our human limitations. It is not impossible that this obsession with geometrization — this desperate need to draw orbitals, bands, or lattices where only blurry probabilities exist — is directly linked to the phobia described in the paper The Fear of the Unexplainable. For reducing the quantum to reassuring shapes is a way to flee the fundamental absurdity of a universe where particles have neither trajectory nor defined position. It is a denial of strangeness, a clinging to the illusion of a classical, manageable, predictable world. Geometry is the refuge of physicists frightened by the metaphysical void. == for Forces and Interactions   == Gravity — Unification — Renormalization — Fundamental constants — Mass In the ΛCDM, forces are treated as fundamental entities, each with its own carrier, field, constants, and symmetries. This assumption generates most of the conceptual difficulties. In the UG.NUG reading, this framework collapses: what the ΛCDM interprets as “forces” are not fundamental ingredients of the universe but the observable behaviors that appear when objects exist or move within the GRID. * Gravity is not an interaction. It has no carrier, no quantum, no fundamental field. It is simply the static behavior of the GRID in the presence of a geometric object. The problem of quantum gravity disappears — not because it is solved, but because it never existed: gravity was never a quantum phenomenon to begin with. * Magnetic effects are the dynamic version of the same behavior when the object moves or rotates. * Renormalization also ceases to be a difficulty: there is nothing to renormalize once these behaviors are no longer treated as fundamental forces. * Mass is not a property of the universe. It is only the human interpretation of certain geometric behaviors that remain fully calculable, even though the quantity itself does not exist. Thus, the conceptual problems associated with forces and interactions in the ΛCDM arise from a single mistake: treating contextual behaviors as fundamental forces. 0ja6io515g8q5mbdrmpfga48h2vp7gv 0 332850 2844876 2844790 2026-11-08T16:20:35Z Sylvain Ribault 2127778 More to the point 2844876 wikitext text/x-wiki [[w:Liouville theory]] is a simple 2d conformal field theory, with applications to quantum gravity, string theory, and statistical physics. The theory can be solved using either a constructive, path integral approach, or the axiomatic conformal bootstrap approach. The path integral approach can be made mathematically rigorous in the context of probability theory, at the price of restricting the central charge to <math display="inline">c\geq 25</math>. The bootstrap approach provides a unique solution in the larger domain <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, and numerically tests its consistency. Correlation functions of Liouville theory are meromorphic functions of <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, with an essential singularity for <math display="inline">c\leq 1</math>. This singularity occurs when the degenerate values <math display="inline">\{P_{(r,s)}=\frac12(r\beta -s\beta^{-1})\}_{r,s\in\mathbb{N}^*}</math> of the momentum become dense on the real line, instead of being isolated from one another. (Notations for the central charge <math display="inline">c=13-6\beta^2-6\beta^{-2}</math> and conformal dimension <math display="inline">\Delta=\frac{c-1}{24}+P^2</math>.) Due to this singularity, no theory with <math display="inline">c\leq 1</math> can be deduced from the original definition of Liouville theory. However, in the conformal bootstrap approach, the assumptions and methods that lead to Liouville theory can be applied for <math display="inline">c\leq 1</math>. The result is a unique conformal field theory with a continuous spectrum <math display="inline">P\in\mathbb{R}</math>.<ref name="rs15"/> This theory has been called <math display="inline">c\leq 1</math> Liouville theory, or imaginary Liouville theory, or timelike Liouville theory. (The latter name originated before the spectrum was found to be spacelike.) In this page we review the conformal bootstrap solution, and discuss whether its features can emerge from a path integral construction. In particular, we argue that the behaviour of fields when their dimension goes to zero is hard to reproduce from the path integral. == Features of correlation functions == === Spectrum and 3-point structure constant === In the conformal bootstrap approach, solving Liouville theory reduces to determining the spectrum and 3-point structure constant. The '''spectrum''' is the set of values of the momentum over which we integrate (or sum) when computing operator product expansions. The spectrum of Liouville theory is continuous for any <math display="inline">c\in\mathbb{C}</math>, and OPEs read <math display="inline">V_{P_1}V_{P_2}\sim \int_\mathbb{R} dP\ V_P</math>. We can compute correlation functions of fields that do not belong to the spectrum: fields <math display="inline">V_P</math> for <math display="inline">P\in\mathbb{C}</math>, and degenerate fields <math display="inline">V^d_{\langle r,s\rangle}</math> for <math display="inline">r,s\in\mathbb{N}^*</math>. The field <math display="inline">V^d_{\langle r,s\rangle}</math> has momentum <math display="inline">P_{(r,s)}</math>, and the OPE <math display="inline">V^d_{\langle r,s\rangle}V_P</math> involves a finite number <math display="inline">rs</math> of primary fields. In particular, the degenerate field <math display="inline">V^d_{\langle 1,1\rangle}</math> with momentum <math display="inline">P=P_{(1,1)}</math> is the identity field, and obeys the singular vector equation <math display="inline">\frac{\partial}{\partial z} V^d_{\langle 1,1\rangle}(z)=0</math>. The '''3-point structure constant''' is a function of 3 momentums <math display="inline">C_{P_1,P_2,P_3}</math>. To constrain it, we study 4-point correlation functions with degenerate fields <math display="inline">\left\langle V^d_{\langle 2,1\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math> and <math display="inline">\left\langle V^d_{\langle 1,2\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math>. Crossing symmetry and single-valuedness of these 4-point functions imply shift equations, which determine how <math display="inline">C_{P_1,P_2,P_3}</math> behaves under <math display="inline">P_k\to P_k+\beta</math> and <math display="inline">P_k\to P_k+\beta^{-1}</math>. Shift equations have a unique solution that is meromorphic in <math display="inline">\beta</math> and <math display="inline">P</math> over <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> and <math display="inline">P\in\mathbb{C}</math>, called the DOZZ formula for Dorn–Otto and Zamolodchikov–Zamolodchikov. There is also a unique solution that is meromorphic over <math display="inline">c\in \mathbb{C}\backslash(25, \infty)</math> and <math display="inline">P\in\mathbb{C}</math>. The latter solution is relevant to <math display="inline">c\leq 1</math> Liouville theory. However, the 3-point structure constant does not known the spectrum of the theory. It also does not know its domain of definition in the complex <math display="inline">c</math>-plane. In fact it does not even know which theory we are studying: the 3-point structure constant of <math display="inline">c\leq 1</math> Liouville theory also appears in critical loop models, which have a discrete spectrum and are defined over the half-plane <math display="inline">\Re c<13</math>.<ref name="rib24"/> === Features of 4-point functions === To really understand Liouville theory with <math display="inline">c\leq 1</math>, it is crucial to study 4-point functions, whose decompositions into conformal blocks are integrals over the spectrum. This determines the spectrum, and explains why the two definitions of Liouville theory for <math display="inline">c\leq 1</math> and <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> are not related by analytic continuation. And this leads to some features of a 4-point function <math display="inline">\left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle</math>, which any proposed construction would have to reproduce: <ol> <li><p>'''Limit of coinciding fields:''' Due to the continuous spectrum, the leading behaviour involves a logarithmic factor: <math display="block">\begin{align} \left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle \underset{z_1\to z_2}{\sim} |z_1-z_2|^{-2P_1^2-2P_2^2-\frac{c-1}{12}} \left|\log|z_1-z_2|\right|^{\alpha}\ , \end{align}</math> where <math display="inline">\alpha=-\frac12</math> for <math display="inline">c\leq 1</math>, and <math display="inline">\alpha=-\frac32</math> otherwise.</p></li> <li><p>'''Analyticity in momentums:''' The 4-point function is a holomorphic function of <math display="inline">P_i</math> for <math display="inline">c\leq 1</math>, and meromorphic otherwise. This is because the structure constants and conformal blocks are themselves holomorphic or meromorphic.</p> <p>These properties hold under the assumption that fields are well-normalized. In the bootstrap approach, we are indeed free to renormalize fields as <math display="inline">V_P(z)\to \lambda_PV_P(z)</math> for any function <math display="inline">\lambda_P</math>, which might have singularities. In correlation functions, we will call factorized the singularities that can be added or removed by field renormalizations.</p></li> <li><p>'''Degenerate values of momentums:''' The limit <math display="inline">\lim_{P\to P_{(r,s)}}V_P</math> is the degenerate field <math display="inline">V^d_{\langle r,s\rangle}</math> unless <math display="inline">c\leq 1</math>, in which case <math display="inline">\lim_{P\to P_{(r,s)}}V_P=V_{P_{(r,s)}}</math>. (Same story with <math display="inline">P\to -P_{(r,s)}</math>.) In particular, for <math display="inline">c\leq 1</math>, any <math display="inline">N\geq 3</math>-point function <math display="inline">\left\langle V_{P_{(1,1)}}(z)\cdots \right\rangle</math> depends on <math display="inline">z</math>, in contrast to <math display="inline">\left\langle V^d_{\langle 1,1\rangle}(z)\cdots \right\rangle</math> which does not.</p></li></ol> These features follow from the known spectrum and structure constant, together with the convergence of the decomposition of correlation functions into structure constants and conformal blocks. This decomposition is an integral over <math display="inline">P</math> that is numerically seen to converge very fast. Failure to converge would call into question the very existence of <math display="inline">c\leq 1</math> Liouville theory. Summary table: <math display="block">\begin{align} \begin{array}{|c|r||c|c|} \hline \# & \text{Property} & c\in (-\infty, 1) & c\in\mathbb{C}\backslash (-\infty, 1) \\ \hline 1 & \text{Log exponent for }z_1\to z_2 & -\frac12 & -\frac32 \\ \hline 2 & \text{Analyticity in } P_i & \text{holomorphic} & \text{meromorphic} \\ \hline 3& \lim_{P\to P_{(r,s)}}V_P & V_{P_{(r,s)}} & V^d_{\langle r,s\rangle} \\ \hline \end{array} \end{align}</math> == Attempts at a construction == === Path integral construction === In known constructions of Liouville theory, <math display="inline">N</math>-point functions are built as a path integral of the type <math display="block">\begin{align} \left\langle \prod_{i=1}^N V_{P_i}(z_i) \right\rangle=\int D\varphi\ \prod_{i=1}^N e^{2(P_i+P_{(1,1)})\varphi(z_i)}\ , \end{align}</math> for some field (or random variable) <math display="inline">\varphi(z)</math>, with a functional measure <math display="inline">D\varphi</math> that includes the action of the theory. A given contruction will work under some conditions on the central charge <math display="inline">c</math> and the momentums <math display="inline">P_i</math>, such as: * The restrictions <math display="inline">c\in (25,\infty)</math> or <math display="inline">c\in (-\infty, 1)</math>: positivity conditions that allows probabilistic methods to apply. * Seiberg bounds on momentums, for convergence of the integral over <math display="inline">\varphi</math>. * Another condition on momentums called charge neutrality, for constructions based on free fields. A simple analogy is the construction of the function <math display="inline">f(z)=\frac{1}{1-z}</math> as the infinite series <math display="inline">\sum_{n=0}^\infty z^n</math>, where the pole of <math display="inline">f(z)</math> at <math display="inline">z=1</math> manifests itself as the condition <math display="inline">|z|<1</math> on the construction. Similarly, we expect that the conditions for constructions of Liouville theory are related to the singularities of correlation functions. === Reproducing known features === Existing attempts at constructing <math display="inline">c\leq 1</math> Liouville theory use similar ideas as the construction that works for <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Features of <math display="inline">c\leq 1</math> Liouville theory are therefore harder to reproduce when they differ more from features at <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Let us discuss the features we discussed previously: <ol> <li><p>'''Limit of coinciding fields:''' This feature does not depend much on the value of <math display="inline">c</math>, and does not look very problematic. All the same, it would be nice to check it.</p></li> <li><p>'''Analyticity in momentums:''' In the case of the 3-point function for <math display="inline">c\leq 1</math>, the known constructions do not yield the well-normalized, holomorphic formula: there are factorized poles at <math display="inline">2P_i\in (-\beta\mathbb{N}^*-\beta^{-1}\mathbb{N})\cup (\beta\mathbb{N}+\beta^{-1}\mathbb{N}^*)</math>.</p> <p>Since the integrand of the path integral is holomorphic in <math display="inline">P_i</math>, we expect that the integral is locally holomorphic, wherever it converges. We expect that the domain of convergence is related to the factorized poles, and should therefore include all (or part) of the interval <math display="inline">P_i\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math>.</p></li> <li><p>'''Degenerate values of momentums:''' In a path integral construction, if the limit commutes with the integral <math display="inline">\int D\varphi</math>, then <math display="inline">\lim_{P\to -P_{(1,1)}} V_{P}(z)=V^d_{\langle 1,1\rangle}(z)</math> is <math display="inline">z</math>-independent. For <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>, this <math display="inline">z</math>-independence is indeed observed. (In particular, the leading behaviour at <math display="inline">z_1\to z_2</math> comes with a <math display="inline">P_i</math>-dependent prefactor that goes to zero if <math display="inline">P_i\to -P_{(1,1)}</math>.) For <math display="inline">c\leq 1</math>, since <math display="inline">-P_{(1,1)}\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math> for any <math display="inline">\beta\in\mathbb{R}_{>0}</math>, there is no reason for the construction to fail for <math display="inline">P=-P_{(1,1)}</math>. Nevertheless, fail it must, since the <math display="inline">z</math>-dependence survives in the limit.</p></li></ol> Conclusion: <blockquote>Any path integral construction is likely valid for <math display="inline">P=-P_{(1,1)}</math>. And if it is valid for <math display="inline">P=-P_{(1,1)}</math>, then it cannot describe <math display="inline">c\leq 1</math> Liouville theory. </blockquote> === Specific attempt === An attempt to construct <math display="inline">c\leq 1</math> Liouville theory is due to Usciati, Guillarmou, Rhodes and Santachiara.<ref name="urgs25"/> In that article, the focus was on the 3-point function, in which case <math display="inline">P=-P_{(1,1)}</math> is outside the domain of validity. The same approach was extended to <math display="inline">N\geq 4</math>-point functions by Cerclé and Usciati,<ref name="cu26"/> and it seems that <math display="inline">P=-P_{(1,1)}</math> is allowed. This would imply that this construction does not agree with the bootstrap construction. == Living without a construction == Even for CFTs whose correlation functions can be computed in the bootstrap approach, a construction can be interesting for two main reasons: * Constructing a CFT proves its existence, which is hard to do in the bootstrap approach. * The Lagrangian is a simple object that encodes broad features of the theory, such as its relations to other theories. This can be very useful in applications. What can be done in <math>c\leq 1</math> Liouville theory, in the absence of a construction? === Proof of existence === Proving the existence of the theory amounts to proving crossing symmetry of all correlation functions. Since we have explicit expressions in terms of structure constants and conformal blocks, this is a well-defined technical problem. A construction could provide an elegant solution, but other approaches are possible. In particular, from the consistency of diagonal minimal models, it might be possible to deduce the existence of <math display="inline">c\leq 1</math> Liouville theory by taking limits. === Application to the Virasoro minimal string === A recent application of <math display="inline">c\leq 1</math> Liouville theory is the construction of the Virasoro minimal string.<ref name="cemr23"/> This application did not need more than the bootstrap definition of the theory, including for finding a matrix integral description of the resulting string theory. A construction would have been convenient, but it was possible to do without it. When it came to deducing correlation numbers of the string theory from correlation functions of the CFT, it was essential to know their analytic properties extensively:<ref name="kl25"/> a construction that would come with limitations on the allowed values of momentums might not have been very helpful. == References == {{Reflist|refs= <ref name="kl25">{{cite web | last1=Khromov | first1=Dmitry | last2=Litvinov | first2=Alexey | title=On correlation numbers $V_{0,4}$ and $V_{1,1}$ in Virasoro Minimal String Theory | website=arXiv.org | date=2025-09-30 | url=https://arxiv.org/abs/2509.25960 | access-date=2026-11-06}}</ref> <ref name="cemr23">{{cite journal | last1=Collier | first1=Scott | last2=Eberhardt | first2=Lorenz | last3=Mühlmann | first3=Beatrix | last4=Rodriguez | first4=Victor A. | title=The Virasoro minimal string | journal=SciPost Physics | publisher=Stichting SciPost | volume=16 | issue=2 | date=2024-02-26 | issn=2542-4653 | doi=10.21468/scipostphys.16.2.057 | doi-access=free | url=https://arxiv.org/abs/2309.10846}}</ref> <ref name="cu26">{{cite web | last1=Cerclé | first1=Baptiste | last2=Usciati | first2=Romain | title=On the local conformal structure of Imaginary Liouville theory | website=arXiv.org | date=2026-08-03 | url=https://arxiv.org/abs/2608.02543 | access-date=2026-11-06}}</ref> <ref name="urgs25">{{cite journal | last1=Usciati | first1=Romain | last2=Guillarmou | first2=Colin | last3=Rhodes | first3=Remi | last4=Santachiara | first4=Raoul | title=Probabilistic Construction of Noncompactified Imaginary Liouville Field Theory | journal=Physical Review Letters | volume=136 | issue=3 | date=2026-01-21 | issn=0031-9007 | doi=10.1103/d723-gk4m | doi-access=free | url=https://arxiv.org/abs/2505.09390}}</ref> <ref name="rib24">{{cite journal | last=Ribault | first=Sylvain | title=Exactly solvable conformal field theories | journal=SciPost Physics Lecture Notes | publisher=Stichting SciPost | url = https://arxiv.org/abs/2411.17262| date=2026-07-22 | issn=2590-1990 | doi=10.21468/scipostphyslectnotes.130 | doi-access=free | page=}}</ref> <ref name="rs15">{{cite journal | last1=Ribault | first1=Sylvain | last2=Santachiara | first2=Raoul | title=Liouville theory with a central charge less than one | journal=Journal of High Energy Physics | volume=2015 | issue=8 | year=2015 | issn=1029-8479 | doi=10.1007/jhep08(2015)109 | doi-access=free | url = https://arxiv.org/abs/1503.02067| access-date=2026-11-06 | page=}}</ref> }} [[Category:Research]] [[Category:Conformal field theory]] fochl4z4dagc6f95z2n624dxrarsjl7 2844877 2844876 2026-11-08T16:21:08Z Sylvain Ribault 2127778 /* Features of 4-point functions */ ce 2844877 wikitext text/x-wiki [[w:Liouville theory]] is a simple 2d conformal field theory, with applications to quantum gravity, string theory, and statistical physics. The theory can be solved using either a constructive, path integral approach, or the axiomatic conformal bootstrap approach. The path integral approach can be made mathematically rigorous in the context of probability theory, at the price of restricting the central charge to <math display="inline">c\geq 25</math>. The bootstrap approach provides a unique solution in the larger domain <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, and numerically tests its consistency. Correlation functions of Liouville theory are meromorphic functions of <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, with an essential singularity for <math display="inline">c\leq 1</math>. This singularity occurs when the degenerate values <math display="inline">\{P_{(r,s)}=\frac12(r\beta -s\beta^{-1})\}_{r,s\in\mathbb{N}^*}</math> of the momentum become dense on the real line, instead of being isolated from one another. (Notations for the central charge <math display="inline">c=13-6\beta^2-6\beta^{-2}</math> and conformal dimension <math display="inline">\Delta=\frac{c-1}{24}+P^2</math>.) Due to this singularity, no theory with <math display="inline">c\leq 1</math> can be deduced from the original definition of Liouville theory. However, in the conformal bootstrap approach, the assumptions and methods that lead to Liouville theory can be applied for <math display="inline">c\leq 1</math>. The result is a unique conformal field theory with a continuous spectrum <math display="inline">P\in\mathbb{R}</math>.<ref name="rs15"/> This theory has been called <math display="inline">c\leq 1</math> Liouville theory, or imaginary Liouville theory, or timelike Liouville theory. (The latter name originated before the spectrum was found to be spacelike.) In this page we review the conformal bootstrap solution, and discuss whether its features can emerge from a path integral construction. In particular, we argue that the behaviour of fields when their dimension goes to zero is hard to reproduce from the path integral. == Features of correlation functions == === Spectrum and 3-point structure constant === In the conformal bootstrap approach, solving Liouville theory reduces to determining the spectrum and 3-point structure constant. The '''spectrum''' is the set of values of the momentum over which we integrate (or sum) when computing operator product expansions. The spectrum of Liouville theory is continuous for any <math display="inline">c\in\mathbb{C}</math>, and OPEs read <math display="inline">V_{P_1}V_{P_2}\sim \int_\mathbb{R} dP\ V_P</math>. We can compute correlation functions of fields that do not belong to the spectrum: fields <math display="inline">V_P</math> for <math display="inline">P\in\mathbb{C}</math>, and degenerate fields <math display="inline">V^d_{\langle r,s\rangle}</math> for <math display="inline">r,s\in\mathbb{N}^*</math>. The field <math display="inline">V^d_{\langle r,s\rangle}</math> has momentum <math display="inline">P_{(r,s)}</math>, and the OPE <math display="inline">V^d_{\langle r,s\rangle}V_P</math> involves a finite number <math display="inline">rs</math> of primary fields. In particular, the degenerate field <math display="inline">V^d_{\langle 1,1\rangle}</math> with momentum <math display="inline">P=P_{(1,1)}</math> is the identity field, and obeys the singular vector equation <math display="inline">\frac{\partial}{\partial z} V^d_{\langle 1,1\rangle}(z)=0</math>. The '''3-point structure constant''' is a function of 3 momentums <math display="inline">C_{P_1,P_2,P_3}</math>. To constrain it, we study 4-point correlation functions with degenerate fields <math display="inline">\left\langle V^d_{\langle 2,1\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math> and <math display="inline">\left\langle V^d_{\langle 1,2\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math>. Crossing symmetry and single-valuedness of these 4-point functions imply shift equations, which determine how <math display="inline">C_{P_1,P_2,P_3}</math> behaves under <math display="inline">P_k\to P_k+\beta</math> and <math display="inline">P_k\to P_k+\beta^{-1}</math>. Shift equations have a unique solution that is meromorphic in <math display="inline">\beta</math> and <math display="inline">P</math> over <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> and <math display="inline">P\in\mathbb{C}</math>, called the DOZZ formula for Dorn–Otto and Zamolodchikov–Zamolodchikov. There is also a unique solution that is meromorphic over <math display="inline">c\in \mathbb{C}\backslash(25, \infty)</math> and <math display="inline">P\in\mathbb{C}</math>. The latter solution is relevant to <math display="inline">c\leq 1</math> Liouville theory. However, the 3-point structure constant does not known the spectrum of the theory. It also does not know its domain of definition in the complex <math display="inline">c</math>-plane. In fact it does not even know which theory we are studying: the 3-point structure constant of <math display="inline">c\leq 1</math> Liouville theory also appears in critical loop models, which have a discrete spectrum and are defined over the half-plane <math display="inline">\Re c<13</math>.<ref name="rib24"/> === Features of 4-point functions === To understand Liouville theory with <math display="inline">c\leq 1</math>, it is crucial to study 4-point functions, whose decompositions into conformal blocks are integrals over the spectrum. This determines the spectrum, and explains why the two definitions of Liouville theory for <math display="inline">c\leq 1</math> and <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> are not related by analytic continuation. And this leads to some features of a 4-point function <math display="inline">\left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle</math>, which any proposed construction would have to reproduce: <ol> <li><p>'''Limit of coinciding fields:''' Due to the continuous spectrum, the leading behaviour involves a logarithmic factor: <math display="block">\begin{align} \left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle \underset{z_1\to z_2}{\sim} |z_1-z_2|^{-2P_1^2-2P_2^2-\frac{c-1}{12}} \left|\log|z_1-z_2|\right|^{\alpha}\ , \end{align}</math> where <math display="inline">\alpha=-\frac12</math> for <math display="inline">c\leq 1</math>, and <math display="inline">\alpha=-\frac32</math> otherwise.</p></li> <li><p>'''Analyticity in momentums:''' The 4-point function is a holomorphic function of <math display="inline">P_i</math> for <math display="inline">c\leq 1</math>, and meromorphic otherwise. This is because the structure constants and conformal blocks are themselves holomorphic or meromorphic.</p> <p>These properties hold under the assumption that fields are well-normalized. In the bootstrap approach, we are indeed free to renormalize fields as <math display="inline">V_P(z)\to \lambda_PV_P(z)</math> for any function <math display="inline">\lambda_P</math>, which might have singularities. In correlation functions, we will call factorized the singularities that can be added or removed by field renormalizations.</p></li> <li><p>'''Degenerate values of momentums:''' The limit <math display="inline">\lim_{P\to P_{(r,s)}}V_P</math> is the degenerate field <math display="inline">V^d_{\langle r,s\rangle}</math> unless <math display="inline">c\leq 1</math>, in which case <math display="inline">\lim_{P\to P_{(r,s)}}V_P=V_{P_{(r,s)}}</math>. (Same story with <math display="inline">P\to -P_{(r,s)}</math>.) In particular, for <math display="inline">c\leq 1</math>, any <math display="inline">N\geq 3</math>-point function <math display="inline">\left\langle V_{P_{(1,1)}}(z)\cdots \right\rangle</math> depends on <math display="inline">z</math>, in contrast to <math display="inline">\left\langle V^d_{\langle 1,1\rangle}(z)\cdots \right\rangle</math> which does not.</p></li></ol> These features follow from the known spectrum and structure constant, together with the convergence of the decomposition of correlation functions into structure constants and conformal blocks. This decomposition is an integral over <math display="inline">P</math> that is numerically seen to converge very fast. Failure to converge would call into question the very existence of <math display="inline">c\leq 1</math> Liouville theory. Summary table: <math display="block">\begin{align} \begin{array}{|c|r||c|c|} \hline \# & \text{Property} & c\in (-\infty, 1) & c\in\mathbb{C}\backslash (-\infty, 1) \\ \hline 1 & \text{Log exponent for }z_1\to z_2 & -\frac12 & -\frac32 \\ \hline 2 & \text{Analyticity in } P_i & \text{holomorphic} & \text{meromorphic} \\ \hline 3& \lim_{P\to P_{(r,s)}}V_P & V_{P_{(r,s)}} & V^d_{\langle r,s\rangle} \\ \hline \end{array} \end{align}</math> == Attempts at a construction == === Path integral construction === In known constructions of Liouville theory, <math display="inline">N</math>-point functions are built as a path integral of the type <math display="block">\begin{align} \left\langle \prod_{i=1}^N V_{P_i}(z_i) \right\rangle=\int D\varphi\ \prod_{i=1}^N e^{2(P_i+P_{(1,1)})\varphi(z_i)}\ , \end{align}</math> for some field (or random variable) <math display="inline">\varphi(z)</math>, with a functional measure <math display="inline">D\varphi</math> that includes the action of the theory. A given contruction will work under some conditions on the central charge <math display="inline">c</math> and the momentums <math display="inline">P_i</math>, such as: * The restrictions <math display="inline">c\in (25,\infty)</math> or <math display="inline">c\in (-\infty, 1)</math>: positivity conditions that allows probabilistic methods to apply. * Seiberg bounds on momentums, for convergence of the integral over <math display="inline">\varphi</math>. * Another condition on momentums called charge neutrality, for constructions based on free fields. A simple analogy is the construction of the function <math display="inline">f(z)=\frac{1}{1-z}</math> as the infinite series <math display="inline">\sum_{n=0}^\infty z^n</math>, where the pole of <math display="inline">f(z)</math> at <math display="inline">z=1</math> manifests itself as the condition <math display="inline">|z|<1</math> on the construction. Similarly, we expect that the conditions for constructions of Liouville theory are related to the singularities of correlation functions. === Reproducing known features === Existing attempts at constructing <math display="inline">c\leq 1</math> Liouville theory use similar ideas as the construction that works for <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Features of <math display="inline">c\leq 1</math> Liouville theory are therefore harder to reproduce when they differ more from features at <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Let us discuss the features we discussed previously: <ol> <li><p>'''Limit of coinciding fields:''' This feature does not depend much on the value of <math display="inline">c</math>, and does not look very problematic. All the same, it would be nice to check it.</p></li> <li><p>'''Analyticity in momentums:''' In the case of the 3-point function for <math display="inline">c\leq 1</math>, the known constructions do not yield the well-normalized, holomorphic formula: there are factorized poles at <math display="inline">2P_i\in (-\beta\mathbb{N}^*-\beta^{-1}\mathbb{N})\cup (\beta\mathbb{N}+\beta^{-1}\mathbb{N}^*)</math>.</p> <p>Since the integrand of the path integral is holomorphic in <math display="inline">P_i</math>, we expect that the integral is locally holomorphic, wherever it converges. We expect that the domain of convergence is related to the factorized poles, and should therefore include all (or part) of the interval <math display="inline">P_i\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math>.</p></li> <li><p>'''Degenerate values of momentums:''' In a path integral construction, if the limit commutes with the integral <math display="inline">\int D\varphi</math>, then <math display="inline">\lim_{P\to -P_{(1,1)}} V_{P}(z)=V^d_{\langle 1,1\rangle}(z)</math> is <math display="inline">z</math>-independent. For <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>, this <math display="inline">z</math>-independence is indeed observed. (In particular, the leading behaviour at <math display="inline">z_1\to z_2</math> comes with a <math display="inline">P_i</math>-dependent prefactor that goes to zero if <math display="inline">P_i\to -P_{(1,1)}</math>.) For <math display="inline">c\leq 1</math>, since <math display="inline">-P_{(1,1)}\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math> for any <math display="inline">\beta\in\mathbb{R}_{>0}</math>, there is no reason for the construction to fail for <math display="inline">P=-P_{(1,1)}</math>. Nevertheless, fail it must, since the <math display="inline">z</math>-dependence survives in the limit.</p></li></ol> Conclusion: <blockquote>Any path integral construction is likely valid for <math display="inline">P=-P_{(1,1)}</math>. And if it is valid for <math display="inline">P=-P_{(1,1)}</math>, then it cannot describe <math display="inline">c\leq 1</math> Liouville theory. </blockquote> === Specific attempt === An attempt to construct <math display="inline">c\leq 1</math> Liouville theory is due to Usciati, Guillarmou, Rhodes and Santachiara.<ref name="urgs25"/> In that article, the focus was on the 3-point function, in which case <math display="inline">P=-P_{(1,1)}</math> is outside the domain of validity. The same approach was extended to <math display="inline">N\geq 4</math>-point functions by Cerclé and Usciati,<ref name="cu26"/> and it seems that <math display="inline">P=-P_{(1,1)}</math> is allowed. This would imply that this construction does not agree with the bootstrap construction. == Living without a construction == Even for CFTs whose correlation functions can be computed in the bootstrap approach, a construction can be interesting for two main reasons: * Constructing a CFT proves its existence, which is hard to do in the bootstrap approach. * The Lagrangian is a simple object that encodes broad features of the theory, such as its relations to other theories. This can be very useful in applications. What can be done in <math>c\leq 1</math> Liouville theory, in the absence of a construction? === Proof of existence === Proving the existence of the theory amounts to proving crossing symmetry of all correlation functions. Since we have explicit expressions in terms of structure constants and conformal blocks, this is a well-defined technical problem. A construction could provide an elegant solution, but other approaches are possible. In particular, from the consistency of diagonal minimal models, it might be possible to deduce the existence of <math display="inline">c\leq 1</math> Liouville theory by taking limits. === Application to the Virasoro minimal string === A recent application of <math display="inline">c\leq 1</math> Liouville theory is the construction of the Virasoro minimal string.<ref name="cemr23"/> This application did not need more than the bootstrap definition of the theory, including for finding a matrix integral description of the resulting string theory. A construction would have been convenient, but it was possible to do without it. When it came to deducing correlation numbers of the string theory from correlation functions of the CFT, it was essential to know their analytic properties extensively:<ref name="kl25"/> a construction that would come with limitations on the allowed values of momentums might not have been very helpful. == References == {{Reflist|refs= <ref name="kl25">{{cite web | last1=Khromov | first1=Dmitry | last2=Litvinov | first2=Alexey | title=On correlation numbers $V_{0,4}$ and $V_{1,1}$ in Virasoro Minimal String Theory | website=arXiv.org | date=2025-09-30 | url=https://arxiv.org/abs/2509.25960 | access-date=2026-11-06}}</ref> <ref name="cemr23">{{cite journal | last1=Collier | first1=Scott | last2=Eberhardt | first2=Lorenz | last3=Mühlmann | first3=Beatrix | last4=Rodriguez | first4=Victor A. | title=The Virasoro minimal string | journal=SciPost Physics | publisher=Stichting SciPost | volume=16 | issue=2 | date=2024-02-26 | issn=2542-4653 | doi=10.21468/scipostphys.16.2.057 | doi-access=free | url=https://arxiv.org/abs/2309.10846}}</ref> <ref name="cu26">{{cite web | last1=Cerclé | first1=Baptiste | last2=Usciati | first2=Romain | title=On the local conformal structure of Imaginary Liouville theory | website=arXiv.org | date=2026-08-03 | url=https://arxiv.org/abs/2608.02543 | access-date=2026-11-06}}</ref> <ref name="urgs25">{{cite journal | last1=Usciati | first1=Romain | last2=Guillarmou | first2=Colin | last3=Rhodes | first3=Remi | last4=Santachiara | first4=Raoul | title=Probabilistic Construction of Noncompactified Imaginary Liouville Field Theory | journal=Physical Review Letters | volume=136 | issue=3 | date=2026-01-21 | issn=0031-9007 | doi=10.1103/d723-gk4m | doi-access=free | url=https://arxiv.org/abs/2505.09390}}</ref> <ref name="rib24">{{cite journal | last=Ribault | first=Sylvain | title=Exactly solvable conformal field theories | journal=SciPost Physics Lecture Notes | publisher=Stichting SciPost | url = https://arxiv.org/abs/2411.17262| date=2026-07-22 | issn=2590-1990 | doi=10.21468/scipostphyslectnotes.130 | doi-access=free | page=}}</ref> <ref name="rs15">{{cite journal | last1=Ribault | first1=Sylvain | last2=Santachiara | first2=Raoul | title=Liouville theory with a central charge less than one | journal=Journal of High Energy Physics | volume=2015 | issue=8 | year=2015 | issn=1029-8479 | doi=10.1007/jhep08(2015)109 | doi-access=free | url = https://arxiv.org/abs/1503.02067| access-date=2026-11-06 | page=}}</ref> }} [[Category:Research]] [[Category:Conformal field theory]] o0fia91x794m6pxeyix4lelcawcf6eq 2844878 2844877 2026-11-08T16:22:49Z Sylvain Ribault 2127778 /* Attempts at a construction */ 2844878 wikitext text/x-wiki [[w:Liouville theory]] is a simple 2d conformal field theory, with applications to quantum gravity, string theory, and statistical physics. The theory can be solved using either a constructive, path integral approach, or the axiomatic conformal bootstrap approach. The path integral approach can be made mathematically rigorous in the context of probability theory, at the price of restricting the central charge to <math display="inline">c\geq 25</math>. The bootstrap approach provides a unique solution in the larger domain <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, and numerically tests its consistency. Correlation functions of Liouville theory are meromorphic functions of <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, with an essential singularity for <math display="inline">c\leq 1</math>. This singularity occurs when the degenerate values <math display="inline">\{P_{(r,s)}=\frac12(r\beta -s\beta^{-1})\}_{r,s\in\mathbb{N}^*}</math> of the momentum become dense on the real line, instead of being isolated from one another. (Notations for the central charge <math display="inline">c=13-6\beta^2-6\beta^{-2}</math> and conformal dimension <math display="inline">\Delta=\frac{c-1}{24}+P^2</math>.) Due to this singularity, no theory with <math display="inline">c\leq 1</math> can be deduced from the original definition of Liouville theory. However, in the conformal bootstrap approach, the assumptions and methods that lead to Liouville theory can be applied for <math display="inline">c\leq 1</math>. The result is a unique conformal field theory with a continuous spectrum <math display="inline">P\in\mathbb{R}</math>.<ref name="rs15"/> This theory has been called <math display="inline">c\leq 1</math> Liouville theory, or imaginary Liouville theory, or timelike Liouville theory. (The latter name originated before the spectrum was found to be spacelike.) In this page we review the conformal bootstrap solution, and discuss whether its features can emerge from a path integral construction. In particular, we argue that the behaviour of fields when their dimension goes to zero is hard to reproduce from the path integral. == Features of correlation functions == === Spectrum and 3-point structure constant === In the conformal bootstrap approach, solving Liouville theory reduces to determining the spectrum and 3-point structure constant. The '''spectrum''' is the set of values of the momentum over which we integrate (or sum) when computing operator product expansions. The spectrum of Liouville theory is continuous for any <math display="inline">c\in\mathbb{C}</math>, and OPEs read <math display="inline">V_{P_1}V_{P_2}\sim \int_\mathbb{R} dP\ V_P</math>. We can compute correlation functions of fields that do not belong to the spectrum: fields <math display="inline">V_P</math> for <math display="inline">P\in\mathbb{C}</math>, and degenerate fields <math display="inline">V^d_{\langle r,s\rangle}</math> for <math display="inline">r,s\in\mathbb{N}^*</math>. The field <math display="inline">V^d_{\langle r,s\rangle}</math> has momentum <math display="inline">P_{(r,s)}</math>, and the OPE <math display="inline">V^d_{\langle r,s\rangle}V_P</math> involves a finite number <math display="inline">rs</math> of primary fields. In particular, the degenerate field <math display="inline">V^d_{\langle 1,1\rangle}</math> with momentum <math display="inline">P=P_{(1,1)}</math> is the identity field, and obeys the singular vector equation <math display="inline">\frac{\partial}{\partial z} V^d_{\langle 1,1\rangle}(z)=0</math>. The '''3-point structure constant''' is a function of 3 momentums <math display="inline">C_{P_1,P_2,P_3}</math>. To constrain it, we study 4-point correlation functions with degenerate fields <math display="inline">\left\langle V^d_{\langle 2,1\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math> and <math display="inline">\left\langle V^d_{\langle 1,2\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math>. Crossing symmetry and single-valuedness of these 4-point functions imply shift equations, which determine how <math display="inline">C_{P_1,P_2,P_3}</math> behaves under <math display="inline">P_k\to P_k+\beta</math> and <math display="inline">P_k\to P_k+\beta^{-1}</math>. Shift equations have a unique solution that is meromorphic in <math display="inline">\beta</math> and <math display="inline">P</math> over <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> and <math display="inline">P\in\mathbb{C}</math>, called the DOZZ formula for Dorn–Otto and Zamolodchikov–Zamolodchikov. There is also a unique solution that is meromorphic over <math display="inline">c\in \mathbb{C}\backslash(25, \infty)</math> and <math display="inline">P\in\mathbb{C}</math>. The latter solution is relevant to <math display="inline">c\leq 1</math> Liouville theory. However, the 3-point structure constant does not known the spectrum of the theory. It also does not know its domain of definition in the complex <math display="inline">c</math>-plane. In fact it does not even know which theory we are studying: the 3-point structure constant of <math display="inline">c\leq 1</math> Liouville theory also appears in critical loop models, which have a discrete spectrum and are defined over the half-plane <math display="inline">\Re c<13</math>.<ref name="rib24"/> === Features of 4-point functions === To understand Liouville theory with <math display="inline">c\leq 1</math>, it is crucial to study 4-point functions, whose decompositions into conformal blocks are integrals over the spectrum. This determines the spectrum, and explains why the two definitions of Liouville theory for <math display="inline">c\leq 1</math> and <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> are not related by analytic continuation. And this leads to some features of a 4-point function <math display="inline">\left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle</math>, which any proposed construction would have to reproduce: <ol> <li><p>'''Limit of coinciding fields:''' Due to the continuous spectrum, the leading behaviour involves a logarithmic factor: <math display="block">\begin{align} \left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle \underset{z_1\to z_2}{\sim} |z_1-z_2|^{-2P_1^2-2P_2^2-\frac{c-1}{12}} \left|\log|z_1-z_2|\right|^{\alpha}\ , \end{align}</math> where <math display="inline">\alpha=-\frac12</math> for <math display="inline">c\leq 1</math>, and <math display="inline">\alpha=-\frac32</math> otherwise.</p></li> <li><p>'''Analyticity in momentums:''' The 4-point function is a holomorphic function of <math display="inline">P_i</math> for <math display="inline">c\leq 1</math>, and meromorphic otherwise. This is because the structure constants and conformal blocks are themselves holomorphic or meromorphic.</p> <p>These properties hold under the assumption that fields are well-normalized. In the bootstrap approach, we are indeed free to renormalize fields as <math display="inline">V_P(z)\to \lambda_PV_P(z)</math> for any function <math display="inline">\lambda_P</math>, which might have singularities. In correlation functions, we will call factorized the singularities that can be added or removed by field renormalizations.</p></li> <li><p>'''Degenerate values of momentums:''' The limit <math display="inline">\lim_{P\to P_{(r,s)}}V_P</math> is the degenerate field <math display="inline">V^d_{\langle r,s\rangle}</math> unless <math display="inline">c\leq 1</math>, in which case <math display="inline">\lim_{P\to P_{(r,s)}}V_P=V_{P_{(r,s)}}</math>. (Same story with <math display="inline">P\to -P_{(r,s)}</math>.) In particular, for <math display="inline">c\leq 1</math>, any <math display="inline">N\geq 3</math>-point function <math display="inline">\left\langle V_{P_{(1,1)}}(z)\cdots \right\rangle</math> depends on <math display="inline">z</math>, in contrast to <math display="inline">\left\langle V^d_{\langle 1,1\rangle}(z)\cdots \right\rangle</math> which does not.</p></li></ol> These features follow from the known spectrum and structure constant, together with the convergence of the decomposition of correlation functions into structure constants and conformal blocks. This decomposition is an integral over <math display="inline">P</math> that is numerically seen to converge very fast. Failure to converge would call into question the very existence of <math display="inline">c\leq 1</math> Liouville theory. Summary table: <math display="block">\begin{align} \begin{array}{|c|r||c|c|} \hline \# & \text{Property} & c\in (-\infty, 1) & c\in\mathbb{C}\backslash (-\infty, 1) \\ \hline 1 & \text{Log exponent for }z_1\to z_2 & -\frac12 & -\frac32 \\ \hline 2 & \text{Analyticity in } P_i & \text{holomorphic} & \text{meromorphic} \\ \hline 3& \lim_{P\to P_{(r,s)}}V_P & V_{P_{(r,s)}} & V^d_{\langle r,s\rangle} \\ \hline \end{array} \end{align}</math> == Path integral construction == === Definition === In known constructions of Liouville theory, <math display="inline">N</math>-point functions are built as a path integral of the type <math display="block">\begin{align} \left\langle \prod_{i=1}^N V_{P_i}(z_i) \right\rangle=\int D\varphi\ \prod_{i=1}^N e^{2(P_i+P_{(1,1)})\varphi(z_i)}\ , \end{align}</math> for some field (or random variable) <math display="inline">\varphi(z)</math>, with a functional measure <math display="inline">D\varphi</math> that includes the action of the theory. A given contruction will work under some conditions on the central charge <math display="inline">c</math> and the momentums <math display="inline">P_i</math>, such as: * The restrictions <math display="inline">c\in (25,\infty)</math> or <math display="inline">c\in (-\infty, 1)</math>: positivity conditions that allows probabilistic methods to apply. * Seiberg bounds on momentums, for convergence of the integral over <math display="inline">\varphi</math>. * Another condition on momentums called charge neutrality, for constructions based on free fields. A simple analogy is the construction of the function <math display="inline">f(z)=\frac{1}{1-z}</math> as the infinite series <math display="inline">\sum_{n=0}^\infty z^n</math>, where the pole of <math display="inline">f(z)</math> at <math display="inline">z=1</math> manifests itself as the condition <math display="inline">|z|<1</math> on the construction. Similarly, we expect that the conditions for constructions of Liouville theory are related to the singularities of correlation functions. === Reproducing known features === Existing attempts at constructing <math display="inline">c\leq 1</math> Liouville theory use similar ideas as the construction that works for <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Features of <math display="inline">c\leq 1</math> Liouville theory are therefore harder to reproduce when they differ more from features at <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Let us discuss the features we discussed previously: <ol> <li><p>'''Limit of coinciding fields:''' This feature does not depend much on the value of <math display="inline">c</math>, and does not look very problematic. All the same, it would be nice to check it.</p></li> <li><p>'''Analyticity in momentums:''' In the case of the 3-point function for <math display="inline">c\leq 1</math>, the known constructions do not yield the well-normalized, holomorphic formula: there are factorized poles at <math display="inline">2P_i\in (-\beta\mathbb{N}^*-\beta^{-1}\mathbb{N})\cup (\beta\mathbb{N}+\beta^{-1}\mathbb{N}^*)</math>.</p> <p>Since the integrand of the path integral is holomorphic in <math display="inline">P_i</math>, we expect that the integral is locally holomorphic, wherever it converges. We expect that the domain of convergence is related to the factorized poles, and should therefore include all (or part) of the interval <math display="inline">P_i\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math>.</p></li> <li><p>'''Degenerate values of momentums:''' In a path integral construction, if the limit commutes with the integral <math display="inline">\int D\varphi</math>, then <math display="inline">\lim_{P\to -P_{(1,1)}} V_{P}(z)=V^d_{\langle 1,1\rangle}(z)</math> is <math display="inline">z</math>-independent. For <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>, this <math display="inline">z</math>-independence is indeed observed. (In particular, the leading behaviour at <math display="inline">z_1\to z_2</math> comes with a <math display="inline">P_i</math>-dependent prefactor that goes to zero if <math display="inline">P_i\to -P_{(1,1)}</math>.) For <math display="inline">c\leq 1</math>, since <math display="inline">-P_{(1,1)}\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math> for any <math display="inline">\beta\in\mathbb{R}_{>0}</math>, there is no reason for the construction to fail for <math display="inline">P=-P_{(1,1)}</math>. Nevertheless, fail it must, since the <math display="inline">z</math>-dependence survives in the limit.</p></li></ol> Conclusion: <blockquote>Any path integral construction is likely valid for <math display="inline">P=-P_{(1,1)}</math>. And if it is valid for <math display="inline">P=-P_{(1,1)}</math>, then it cannot describe <math display="inline">c\leq 1</math> Liouville theory. </blockquote> === Specific attempt === An attempt to construct <math display="inline">c\leq 1</math> Liouville theory is due to Usciati, Guillarmou, Rhodes and Santachiara.<ref name="urgs25"/> In that article, the focus was on the 3-point function, in which case <math display="inline">P=-P_{(1,1)}</math> is outside the domain of validity. The same approach was extended to <math display="inline">N\geq 4</math>-point functions by Cerclé and Usciati,<ref name="cu26"/> and it seems that <math display="inline">P=-P_{(1,1)}</math> is allowed. This would imply that this construction does not agree with the bootstrap construction. == Living without a construction == Even for CFTs whose correlation functions can be computed in the bootstrap approach, a construction can be interesting for two main reasons: * Constructing a CFT proves its existence, which is hard to do in the bootstrap approach. * The Lagrangian is a simple object that encodes broad features of the theory, such as its relations to other theories. This can be very useful in applications. What can be done in <math>c\leq 1</math> Liouville theory, in the absence of a construction? === Proof of existence === Proving the existence of the theory amounts to proving crossing symmetry of all correlation functions. Since we have explicit expressions in terms of structure constants and conformal blocks, this is a well-defined technical problem. A construction could provide an elegant solution, but other approaches are possible. In particular, from the consistency of diagonal minimal models, it might be possible to deduce the existence of <math display="inline">c\leq 1</math> Liouville theory by taking limits. === Application to the Virasoro minimal string === A recent application of <math display="inline">c\leq 1</math> Liouville theory is the construction of the Virasoro minimal string.<ref name="cemr23"/> This application did not need more than the bootstrap definition of the theory, including for finding a matrix integral description of the resulting string theory. A construction would have been convenient, but it was possible to do without it. When it came to deducing correlation numbers of the string theory from correlation functions of the CFT, it was essential to know their analytic properties extensively:<ref name="kl25"/> a construction that would come with limitations on the allowed values of momentums might not have been very helpful. == References == {{Reflist|refs= <ref name="kl25">{{cite web | last1=Khromov | first1=Dmitry | last2=Litvinov | first2=Alexey | title=On correlation numbers $V_{0,4}$ and $V_{1,1}$ in Virasoro Minimal String Theory | website=arXiv.org | date=2025-09-30 | url=https://arxiv.org/abs/2509.25960 | access-date=2026-11-06}}</ref> <ref name="cemr23">{{cite journal | last1=Collier | first1=Scott | last2=Eberhardt | first2=Lorenz | last3=Mühlmann | first3=Beatrix | last4=Rodriguez | first4=Victor A. | title=The Virasoro minimal string | journal=SciPost Physics | publisher=Stichting SciPost | volume=16 | issue=2 | date=2024-02-26 | issn=2542-4653 | doi=10.21468/scipostphys.16.2.057 | doi-access=free | url=https://arxiv.org/abs/2309.10846}}</ref> <ref name="cu26">{{cite web | last1=Cerclé | first1=Baptiste | last2=Usciati | first2=Romain | title=On the local conformal structure of Imaginary Liouville theory | website=arXiv.org | date=2026-08-03 | url=https://arxiv.org/abs/2608.02543 | access-date=2026-11-06}}</ref> <ref name="urgs25">{{cite journal | last1=Usciati | first1=Romain | last2=Guillarmou | first2=Colin | last3=Rhodes | first3=Remi | last4=Santachiara | first4=Raoul | title=Probabilistic Construction of Noncompactified Imaginary Liouville Field Theory | journal=Physical Review Letters | volume=136 | issue=3 | date=2026-01-21 | issn=0031-9007 | doi=10.1103/d723-gk4m | doi-access=free | url=https://arxiv.org/abs/2505.09390}}</ref> <ref name="rib24">{{cite journal | last=Ribault | first=Sylvain | title=Exactly solvable conformal field theories | journal=SciPost Physics Lecture Notes | publisher=Stichting SciPost | url = https://arxiv.org/abs/2411.17262| date=2026-07-22 | issn=2590-1990 | doi=10.21468/scipostphyslectnotes.130 | doi-access=free | page=}}</ref> <ref name="rs15">{{cite journal | last1=Ribault | first1=Sylvain | last2=Santachiara | first2=Raoul | title=Liouville theory with a central charge less than one | journal=Journal of High Energy Physics | volume=2015 | issue=8 | year=2015 | issn=1029-8479 | doi=10.1007/jhep08(2015)109 | doi-access=free | url = https://arxiv.org/abs/1503.02067| access-date=2026-11-06 | page=}}</ref> }} [[Category:Research]] [[Category:Conformal field theory]] cg6cm4cq32nvielowvv2we2bndqwmpf 2844879 2844878 2026-11-08T16:32:10Z Sylvain Ribault 2127778 /* Specific attempt */ 2844879 wikitext text/x-wiki [[w:Liouville theory]] is a simple 2d conformal field theory, with applications to quantum gravity, string theory, and statistical physics. The theory can be solved using either a constructive, path integral approach, or the axiomatic conformal bootstrap approach. The path integral approach can be made mathematically rigorous in the context of probability theory, at the price of restricting the central charge to <math display="inline">c\geq 25</math>. The bootstrap approach provides a unique solution in the larger domain <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, and numerically tests its consistency. Correlation functions of Liouville theory are meromorphic functions of <math display="inline">c\in \mathbb{C}\backslash(-\infty , 1)</math>, with an essential singularity for <math display="inline">c\leq 1</math>. This singularity occurs when the degenerate values <math display="inline">\{P_{(r,s)}=\frac12(r\beta -s\beta^{-1})\}_{r,s\in\mathbb{N}^*}</math> of the momentum become dense on the real line, instead of being isolated from one another. (Notations for the central charge <math display="inline">c=13-6\beta^2-6\beta^{-2}</math> and conformal dimension <math display="inline">\Delta=\frac{c-1}{24}+P^2</math>.) Due to this singularity, no theory with <math display="inline">c\leq 1</math> can be deduced from the original definition of Liouville theory. However, in the conformal bootstrap approach, the assumptions and methods that lead to Liouville theory can be applied for <math display="inline">c\leq 1</math>. The result is a unique conformal field theory with a continuous spectrum <math display="inline">P\in\mathbb{R}</math>.<ref name="rs15"/> This theory has been called <math display="inline">c\leq 1</math> Liouville theory, or imaginary Liouville theory, or timelike Liouville theory. (The latter name originated before the spectrum was found to be spacelike.) In this page we review the conformal bootstrap solution, and discuss whether its features can emerge from a path integral construction. In particular, we argue that the behaviour of fields when their dimension goes to zero is hard to reproduce from the path integral. == Features of correlation functions == === Spectrum and 3-point structure constant === In the conformal bootstrap approach, solving Liouville theory reduces to determining the spectrum and 3-point structure constant. The '''spectrum''' is the set of values of the momentum over which we integrate (or sum) when computing operator product expansions. The spectrum of Liouville theory is continuous for any <math display="inline">c\in\mathbb{C}</math>, and OPEs read <math display="inline">V_{P_1}V_{P_2}\sim \int_\mathbb{R} dP\ V_P</math>. We can compute correlation functions of fields that do not belong to the spectrum: fields <math display="inline">V_P</math> for <math display="inline">P\in\mathbb{C}</math>, and degenerate fields <math display="inline">V^d_{\langle r,s\rangle}</math> for <math display="inline">r,s\in\mathbb{N}^*</math>. The field <math display="inline">V^d_{\langle r,s\rangle}</math> has momentum <math display="inline">P_{(r,s)}</math>, and the OPE <math display="inline">V^d_{\langle r,s\rangle}V_P</math> involves a finite number <math display="inline">rs</math> of primary fields. In particular, the degenerate field <math display="inline">V^d_{\langle 1,1\rangle}</math> with momentum <math display="inline">P=P_{(1,1)}</math> is the identity field, and obeys the singular vector equation <math display="inline">\frac{\partial}{\partial z} V^d_{\langle 1,1\rangle}(z)=0</math>. The '''3-point structure constant''' is a function of 3 momentums <math display="inline">C_{P_1,P_2,P_3}</math>. To constrain it, we study 4-point correlation functions with degenerate fields <math display="inline">\left\langle V^d_{\langle 2,1\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math> and <math display="inline">\left\langle V^d_{\langle 1,2\rangle}V_{P_1}V_{P_2}V_{P_3}\right\rangle</math>. Crossing symmetry and single-valuedness of these 4-point functions imply shift equations, which determine how <math display="inline">C_{P_1,P_2,P_3}</math> behaves under <math display="inline">P_k\to P_k+\beta</math> and <math display="inline">P_k\to P_k+\beta^{-1}</math>. Shift equations have a unique solution that is meromorphic in <math display="inline">\beta</math> and <math display="inline">P</math> over <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> and <math display="inline">P\in\mathbb{C}</math>, called the DOZZ formula for Dorn–Otto and Zamolodchikov–Zamolodchikov. There is also a unique solution that is meromorphic over <math display="inline">c\in \mathbb{C}\backslash(25, \infty)</math> and <math display="inline">P\in\mathbb{C}</math>. The latter solution is relevant to <math display="inline">c\leq 1</math> Liouville theory. However, the 3-point structure constant does not known the spectrum of the theory. It also does not know its domain of definition in the complex <math display="inline">c</math>-plane. In fact it does not even know which theory we are studying: the 3-point structure constant of <math display="inline">c\leq 1</math> Liouville theory also appears in critical loop models, which have a discrete spectrum and are defined over the half-plane <math display="inline">\Re c<13</math>.<ref name="rib24"/> === Features of 4-point functions === To understand Liouville theory with <math display="inline">c\leq 1</math>, it is crucial to study 4-point functions, whose decompositions into conformal blocks are integrals over the spectrum. This determines the spectrum, and explains why the two definitions of Liouville theory for <math display="inline">c\leq 1</math> and <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math> are not related by analytic continuation. And this leads to some features of a 4-point function <math display="inline">\left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle</math>, which any proposed construction would have to reproduce: <ol> <li><p>'''Limit of coinciding fields:''' Due to the continuous spectrum, the leading behaviour involves a logarithmic factor: <math display="block">\begin{align} \left\langle \prod_{i=1}^4V_{P_i}(z_i)\right\rangle \underset{z_1\to z_2}{\sim} |z_1-z_2|^{-2P_1^2-2P_2^2-\frac{c-1}{12}} \left|\log|z_1-z_2|\right|^{\alpha}\ , \end{align}</math> where <math display="inline">\alpha=-\frac12</math> for <math display="inline">c\leq 1</math>, and <math display="inline">\alpha=-\frac32</math> otherwise.</p></li> <li><p>'''Analyticity in momentums:''' The 4-point function is a holomorphic function of <math display="inline">P_i</math> for <math display="inline">c\leq 1</math>, and meromorphic otherwise. This is because the structure constants and conformal blocks are themselves holomorphic or meromorphic.</p> <p>These properties hold under the assumption that fields are well-normalized. In the bootstrap approach, we are indeed free to renormalize fields as <math display="inline">V_P(z)\to \lambda_PV_P(z)</math> for any function <math display="inline">\lambda_P</math>, which might have singularities. In correlation functions, we will call factorized the singularities that can be added or removed by field renormalizations.</p></li> <li><p>'''Degenerate values of momentums:''' The limit <math display="inline">\lim_{P\to P_{(r,s)}}V_P</math> is the degenerate field <math display="inline">V^d_{\langle r,s\rangle}</math> unless <math display="inline">c\leq 1</math>, in which case <math display="inline">\lim_{P\to P_{(r,s)}}V_P=V_{P_{(r,s)}}</math>. (Same story with <math display="inline">P\to -P_{(r,s)}</math>.) In particular, for <math display="inline">c\leq 1</math>, any <math display="inline">N\geq 3</math>-point function <math display="inline">\left\langle V_{P_{(1,1)}}(z)\cdots \right\rangle</math> depends on <math display="inline">z</math>, in contrast to <math display="inline">\left\langle V^d_{\langle 1,1\rangle}(z)\cdots \right\rangle</math> which does not.</p></li></ol> These features follow from the known spectrum and structure constant, together with the convergence of the decomposition of correlation functions into structure constants and conformal blocks. This decomposition is an integral over <math display="inline">P</math> that is numerically seen to converge very fast. Failure to converge would call into question the very existence of <math display="inline">c\leq 1</math> Liouville theory. Summary table: <math display="block">\begin{align} \begin{array}{|c|r||c|c|} \hline \# & \text{Property} & c\in (-\infty, 1) & c\in\mathbb{C}\backslash (-\infty, 1) \\ \hline 1 & \text{Log exponent for }z_1\to z_2 & -\frac12 & -\frac32 \\ \hline 2 & \text{Analyticity in } P_i & \text{holomorphic} & \text{meromorphic} \\ \hline 3& \lim_{P\to P_{(r,s)}}V_P & V_{P_{(r,s)}} & V^d_{\langle r,s\rangle} \\ \hline \end{array} \end{align}</math> == Path integral construction == === Definition === In known constructions of Liouville theory, <math display="inline">N</math>-point functions are built as a path integral of the type <math display="block">\begin{align} \left\langle \prod_{i=1}^N V_{P_i}(z_i) \right\rangle=\int D\varphi\ \prod_{i=1}^N e^{2(P_i+P_{(1,1)})\varphi(z_i)}\ , \end{align}</math> for some field (or random variable) <math display="inline">\varphi(z)</math>, with a functional measure <math display="inline">D\varphi</math> that includes the action of the theory. A given contruction will work under some conditions on the central charge <math display="inline">c</math> and the momentums <math display="inline">P_i</math>, such as: * The restrictions <math display="inline">c\in (25,\infty)</math> or <math display="inline">c\in (-\infty, 1)</math>: positivity conditions that allows probabilistic methods to apply. * Seiberg bounds on momentums, for convergence of the integral over <math display="inline">\varphi</math>. * Another condition on momentums called charge neutrality, for constructions based on free fields. A simple analogy is the construction of the function <math display="inline">f(z)=\frac{1}{1-z}</math> as the infinite series <math display="inline">\sum_{n=0}^\infty z^n</math>, where the pole of <math display="inline">f(z)</math> at <math display="inline">z=1</math> manifests itself as the condition <math display="inline">|z|<1</math> on the construction. Similarly, we expect that the conditions for constructions of Liouville theory are related to the singularities of correlation functions. === Reproducing known features === Existing attempts at constructing <math display="inline">c\leq 1</math> Liouville theory use similar ideas as the construction that works for <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Features of <math display="inline">c\leq 1</math> Liouville theory are therefore harder to reproduce when they differ more from features at <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>. Let us discuss the features we discussed previously: <ol> <li><p>'''Limit of coinciding fields:''' This feature does not depend much on the value of <math display="inline">c</math>, and does not look very problematic. All the same, it would be nice to check it.</p></li> <li><p>'''Analyticity in momentums:''' In the case of the 3-point function for <math display="inline">c\leq 1</math>, the known constructions do not yield the well-normalized, holomorphic formula: there are factorized poles at <math display="inline">2P_i\in (-\beta\mathbb{N}^*-\beta^{-1}\mathbb{N})\cup (\beta\mathbb{N}+\beta^{-1}\mathbb{N}^*)</math>.</p> <p>Since the integrand of the path integral is holomorphic in <math display="inline">P_i</math>, we expect that the integral is locally holomorphic, wherever it converges. We expect that the domain of convergence is related to the factorized poles, and should therefore include all (or part) of the interval <math display="inline">P_i\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math>.</p></li> <li><p>'''Degenerate values of momentums:''' In a path integral construction, if the limit commutes with the integral <math display="inline">\int D\varphi</math>, then <math display="inline">\lim_{P\to -P_{(1,1)}} V_{P}(z)=V^d_{\langle 1,1\rangle}(z)</math> is <math display="inline">z</math>-independent. For <math display="inline">c\in \mathbb{C}\backslash(-\infty, 1)</math>, this <math display="inline">z</math>-independence is indeed observed. (In particular, the leading behaviour at <math display="inline">z_1\to z_2</math> comes with a <math display="inline">P_i</math>-dependent prefactor that goes to zero if <math display="inline">P_i\to -P_{(1,1)}</math>.) For <math display="inline">c\leq 1</math>, since <math display="inline">-P_{(1,1)}\in (-\frac{\beta}{2},\frac{\beta^{-1}}{2})</math> for any <math display="inline">\beta\in\mathbb{R}_{>0}</math>, there is no reason for the construction to fail for <math display="inline">P=-P_{(1,1)}</math>. Nevertheless, fail it must, since the <math display="inline">z</math>-dependence survives in the limit.</p></li></ol> Conclusion: <blockquote>Any path integral construction is likely valid for <math display="inline">P=-P_{(1,1)}</math>. And if it is valid for <math display="inline">P=-P_{(1,1)}</math>, then it cannot describe <math display="inline">c\leq 1</math> Liouville theory. </blockquote> === Specific attempt === An attempt to construct <math display="inline">c\leq 1</math> Liouville theory is due to Usciati, Guillarmou, Rhodes and Santachiara.<ref name="urgs25"/> In that article, the focus was on the 3-point function, in which case <math display="inline">P=-P_{(1,1)}</math> is outside the domain of validity. The same approach was extended to <math display="inline">N\geq 4</math>-point functions by Cerclé and Usciati,<ref name="cu26"/> and it seems that <math display="inline">P=-P_{(1,1)}</math> is allowed. This would imply that this construction does not agree with the known theory.<ref name="rs15"/> The authors reach the same conclusion by comparing spectrums, but stop short of claiming that they have found a new CFT. == Living without a construction == Even for CFTs whose correlation functions can be computed in the bootstrap approach, a construction can be interesting for two main reasons: * Constructing a CFT proves its existence, which is hard to do in the bootstrap approach. * The Lagrangian is a simple object that encodes broad features of the theory, such as its relations to other theories. This can be very useful in applications. What can be done in <math>c\leq 1</math> Liouville theory, in the absence of a construction? === Proof of existence === Proving the existence of the theory amounts to proving crossing symmetry of all correlation functions. Since we have explicit expressions in terms of structure constants and conformal blocks, this is a well-defined technical problem. A construction could provide an elegant solution, but other approaches are possible. In particular, from the consistency of diagonal minimal models, it might be possible to deduce the existence of <math display="inline">c\leq 1</math> Liouville theory by taking limits. === Application to the Virasoro minimal string === A recent application of <math display="inline">c\leq 1</math> Liouville theory is the construction of the Virasoro minimal string.<ref name="cemr23"/> This application did not need more than the bootstrap definition of the theory, including for finding a matrix integral description of the resulting string theory. A construction would have been convenient, but it was possible to do without it. When it came to deducing correlation numbers of the string theory from correlation functions of the CFT, it was essential to know their analytic properties extensively:<ref name="kl25"/> a construction that would come with limitations on the allowed values of momentums might not have been very helpful. == References == {{Reflist|refs= <ref name="kl25">{{cite web | last1=Khromov | first1=Dmitry | last2=Litvinov | first2=Alexey | title=On correlation numbers $V_{0,4}$ and $V_{1,1}$ in Virasoro Minimal String Theory | website=arXiv.org | date=2025-09-30 | url=https://arxiv.org/abs/2509.25960 | access-date=2026-11-06}}</ref> <ref name="cemr23">{{cite journal | last1=Collier | first1=Scott | last2=Eberhardt | first2=Lorenz | last3=Mühlmann | first3=Beatrix | last4=Rodriguez | first4=Victor A. | title=The Virasoro minimal string | journal=SciPost Physics | publisher=Stichting SciPost | volume=16 | issue=2 | date=2024-02-26 | issn=2542-4653 | doi=10.21468/scipostphys.16.2.057 | doi-access=free | url=https://arxiv.org/abs/2309.10846}}</ref> <ref name="cu26">{{cite web | last1=Cerclé | first1=Baptiste | last2=Usciati | first2=Romain | title=On the local conformal structure of Imaginary Liouville theory | website=arXiv.org | date=2026-08-03 | url=https://arxiv.org/abs/2608.02543 | access-date=2026-11-06}}</ref> <ref name="urgs25">{{cite journal | last1=Usciati | first1=Romain | last2=Guillarmou | first2=Colin | last3=Rhodes | first3=Remi | last4=Santachiara | first4=Raoul | title=Probabilistic Construction of Noncompactified Imaginary Liouville Field Theory | journal=Physical Review Letters | volume=136 | issue=3 | date=2026-01-21 | issn=0031-9007 | doi=10.1103/d723-gk4m | doi-access=free | url=https://arxiv.org/abs/2505.09390}}</ref> <ref name="rib24">{{cite journal | last=Ribault | first=Sylvain | title=Exactly solvable conformal field theories | journal=SciPost Physics Lecture Notes | publisher=Stichting SciPost | url = https://arxiv.org/abs/2411.17262| date=2026-07-22 | issn=2590-1990 | doi=10.21468/scipostphyslectnotes.130 | doi-access=free | page=}}</ref> <ref name="rs15">{{cite journal | last1=Ribault | first1=Sylvain | last2=Santachiara | first2=Raoul | title=Liouville theory with a central charge less than one | journal=Journal of High Energy Physics | volume=2015 | issue=8 | year=2015 | issn=1029-8479 | doi=10.1007/jhep08(2015)109 | doi-access=free | url = https://arxiv.org/abs/1503.02067| access-date=2026-11-06 | page=}}</ref> }} [[Category:Research]] [[Category:Conformal field theory]] po7jrh00kgrnkvtdpxix8uktlogzcyp 2 332868 2844869 2026-11-08T15:05:55Z CorraleH 2903442 Open Research Book - Assessing Wikimedia Research Reproducibility/Project log 2844869 wikitext text/x-wiki = Project log = This page documents preliminary meetings, methodological discussions and organisational activities related to the research project ''Assessing Wikimedia Research Reproducibility: A Study on Collaborative Practices''. == February 2026 — Initial coordination == Hector Gabriel Corrale de Matos, Alexandre Hannud Abdo (CNRS) and Lilian Cássia Bórnia Jacob (USP) exchanged emails to organise the research activities. A meeting was scheduled for 27 February 2026 to discuss the project and its next steps. == September 2026 — Research preparation == '''2 September 2026.''' Hector informed Alexandre about preliminary contacts concerning bibliographic data availability and support for literature retrieval. Alexandre suggested evaluating the reuse of computational tools developed in previous research on open scientific hardware ([https://github.com/amchagas/open-hardware-supply Open Hardware Supply]). '''16 September 2026.''' Hector, Alexandre and Lilian met to discuss the organisation of the research notebook, data collection and preregistration. Alexandre shared examples of research documentation using Wikimedia platforms: [https://en.wikiversity.org/wiki/Just_sustainability_transitions:_a_living_review Just sustainability transitions: a living review] — [https://meta.wikimedia.org/wiki/Research Research documentation on Meta-Wiki]. [https://pt.wikiversity.org/wiki/Pesquisaérito_crack_Brasil Inquérito crack Brasil]. [https://en.wikiversity.org/wiki/The_dynamics_and_social_organization_of_innovation_in_the_field_of_oncology The dynamics and social organization of innovation in the field of oncology]. [https://github.com/amchagas/open-hardware-supply Open Hardware Supply]. '''17 September 2026.''' Alexandre shared [https://tabernacle.toolforge.org/ Tabernacle], a tool for working with Wikidata items in tabular format. Further discussions were proposed as this research notebook, data collection procedures and preregistration advanced. == September–October 2026 — Bibliographic search planning == '''26 September 2026.''' Research assistant Lilian Viana prepared a preliminary assessment of bibliographic resources and reporting protocols. The document examined language restrictions, metadata retrieval and database coverage. Dimensions was considered a relevant source, while Zenodo presented limitations related to document filtering and batch export. OSF Preprints and arXiv were evaluated using Zotero Connector. Lilian also suggested examining [https://www.equator-network.org/reporting-guidelines/entreq/ ENTREQ] and an [https://dl.acm.org/doi/pdf/10.1145/3685266 umbrella review on reporting quality in HCI]. '''28 September 2026.''' Hector circulated the Phase I search strategy prepared with support from Lilian Viana and invited comments from Alexandre and other collaborators. '''26 October 2026.''' Further correspondence addressed the possible inclusion of Redalyc and SciELO, the preservation of bibliographic metadata and identifiers, and the proposed schedule for record extraction. == Research data management proposal == The [https://www.g-node.org/ German Neuroinformatics Node (G-Node)] and its [https://gin.g-node.org/ G-Node Data Infrastructure (GIN)] were considered as options for the final storage and sharing of research datasets. GIN supports dataset versioning, private and public repositories, and collaboration between researchers. Its potential use was discussed in relation to long-term data preservation, open science and research reproducibility. The final repository selection remains to be documented. ba7jeuskvyq23ix6c2zjyi7khcu08c4 2 332869 2844871 2026-11-08T15:22:37Z CorraleH 2903442 Open Research Book - Assessing Wikimedia Research Reproducibility/Corpus and search strategy 2844871 wikitext text/x-wiki = Corpus and search strategy = This page documents the preliminary planning of the bibliographic corpus and search strategy for the research project ''Assessing Wikimedia Research Reproducibility: A Study on Collaborative Practices''. The initial assessment was prepared by research assistant Lilian Viana in September 2026. == Corpus definition == The preliminary planning considered publication types, language restrictions and eligibility criteria. Particular attention was given to the different names of Wikimedia projects across languages and their implications for bibliographic retrieval. {{Collapsible |'''Corpus definition and eligibility''' |The study was planned to examine scientific articles related to Wikimedia research. The preliminary assessment considered: * Publication types and eligibility criteria. * Language restrictions and multilingual search terms. * Bibliographic coverage and metadata availability. * Identification and retrieval of scientific articles. Language restrictions required further consideration. Some Wikimedia projects have different names across languages, which may affect record retrieval. Dimensions, for example, does not provide a language filter, requiring language screening after retrieval. |collapsed=true |expandtext=Show details |collapsetext=Hide details }} == Bibliographic databases and resources == The preliminary assessment examined Dimensions, Zenodo, OSF Preprints and arXiv. The comparison considered the relevance of each resource to the proposed corpus, document filtering and reference export options. {{Collapsible |'''Database assessment and export procedures''' |'''Dimensions''' Dimensions was considered relevant because of its multidisciplinary coverage and indexing of publications identified through DOI records. Although the platform has limitations for complex search expressions, the planned search terms were relatively simple. Dimensions supports RIS export. '''Zenodo''' Zenodo was considered less suitable because the study intended to analyse scientific articles. The platform does not provide a direct filter restricted to journal articles. Additional screening would therefore be necessary. Limitations in batch export and potential overlap with DOI-indexed resources were also considered. '''OSF Preprints''' OSF Preprints was evaluated as a possible source for literature distributed through preprint repositories. Its inclusion required clarification of eligible publication types. Zotero Connector was identified as an option for collecting references. '''arXiv''' Zotero Connector was tested as an option for collecting references from arXiv. The proposed procedure involved capturing records from successive search results pages. |collapsed=true |expandtext=Show database assessment |collapsetext=Hide details }} == Previous research and search terms == The planning considered a previous bibliographic study by Buttliere and colleagues as a reference for identifying Wikimedia-related publications and developing search expressions. {{Collapsible |'''Previous bibliographic research and search expression''' |The previous study used [https://openalex.org/ OpenAlex] to retrieve publications related to Wikimedia projects. * Period: 2015–2024. * Initial sample: 9,137 records. * Retrieved results: 8,379 records. The reported search expression included: <code>Wikipedia OR Wikimedia OR Wikidata OR Wikisource OR Wikinews OR Wikibooks OR Wikispecies OR Wikivoyage OR Wikiquote OR Wiktionary OR Wikiversity OR Wikimania OR MediaWiki OR Wikifunctions</code> These terms and figures were examined as a methodological reference. They do not represent the final search strategy of the present project. |collapsed=true |expandtext=Show search terms |collapsetext=Hide details }} == Search documentation and methodological decisions == The preliminary assessment also examined reporting guidelines and methodological references. Several questions remained open concerning database selection, language restrictions, eligible publication types and reference management. {{Collapsible |'''Reporting guidelines and pending decisions''' |'''Reporting guidelines''' Lilian suggested examining the following materials to support the documentation of search and selection procedures: * [https://www.equator-network.org/reporting-guidelines/entreq/ ENTREQ — Enhancing Transparency in Reporting the Synthesis of Qualitative Research]. * [https://dl.acm.org/doi/10.1145/3685266 An Umbrella Review of Reporting Quality in CHI Systematic Reviews: Guiding Questions and Best Practices for HCI]. '''Pending methodological decisions''' * Definition of language restrictions. * Eligibility of preprints and other publication types. * Selection of bibliographic databases. * Standardisation of metadata and identifiers. * Export procedures and subsequent record screening. These elements were identified during preliminary planning and required further discussion before the search strategy could be finalised. |collapsed=true |expandtext=Show methodological considerations |collapsetext=Hide details }} 2lczn4vicb6415w5n4bpqxfvlu17yuj 6 332872 2844894 2026-11-08T21:06:28Z SILamal 3001524 This paper presents a rigorous mathematical framework for the instantaneous inter-conversion of total space into total time and its inverse. Building upon the foundational concepts established in my previous paper “Theory of Original Gravity Revisited: Unified Field Theory, Starting out from Quantum Formulation to the Manifold Geometry”, this paper refines the core concepts, terminology, and governing equations bridging quantum formulation and manifold geometry into a more cohesive unified fi... 2844894 wikitext text/x-wiki == Summary == This paper presents a rigorous mathematical framework for the instantaneous inter-conversion of total space into total time and its inverse. Building upon the foundational concepts established in my previous paper “Theory of Original Gravity Revisited: Unified Field Theory, Starting out from Quantum Formulation to the Manifold Geometry”, this paper refines the core concepts, terminology, and governing equations bridging quantum formulation and manifold geometry into a more cohesive unified field theory. Furthermore, this paper demonstrates the utility of this model in resolving long-standing foundational problems, discusses its broader of the implications for future theoretical physics, and underscore the mathematical validity underlying this framework. == Licensing == {{self|GFDL|cc-by-4.0}} h6s5cqvidac02sdttnx3639j7wtmed9 0 332873 2844915 2026-11-09T00:03:32Z GODSAUDITION SYMPHOGRAPHY 3114035 Created page with " = SYMPHOGRAPHY™ = '''SYMPHOGRAPHY™''' is an original interdisciplinary research framework developed through '''GODSAUDITION™ SYMPHOGRAPHY™''' for the investigation, mapping, comparison, translation, and composition of structural relationships across creative and analytical media. This Wikiversity resource documents the developing research architecture, terminology, methodology, chronology, and applications of SYMPHOGRAPHY™. The material presented here include..." 2844915 wikitext text/x-wiki = SYMPHOGRAPHY™ = '''SYMPHOGRAPHY™''' is an original interdisciplinary research framework developed through '''GODSAUDITION™ SYMPHOGRAPHY™''' for the investigation, mapping, comparison, translation, and composition of structural relationships across creative and analytical media. This Wikiversity resource documents the developing research architecture, terminology, methodology, chronology, and applications of SYMPHOGRAPHY™. The material presented here includes '''original research''' by GODSAUDITION™ SYMPHOGRAPHY™ and should be read as documentation of an evolving interdisciplinary system rather than as an established academic consensus. == Documented Genesis and Foundational Chronology == The development of SYMPHOGRAPHY™ occurred nonlinearly. Three dates distinguish the developmental beginning, the earliest presently recovered explicit written naming record, and the formal foundational establishment of the discipline. '''July 13, 2025 — Developmental Beginning''' The documented foundational writing period began on July 13, 2025, during an intensive period of literary, conceptual, artistic, musical, structural, and interdisciplinary creation. This period represents the developmental environment from which the architecture later named SYMPHOGRAPHY™ emerged. '''July 28, 2025 — Earliest Explicit Written Naming Record''' By July 28, 2025, the term '''SYMPHOGRAPHY''' and the designation '''GODSAUDITION™ SYMPHOGRAPHY™''' were explicitly documented in connection with the developing interdisciplinary framework. This is the earliest presently recovered written record in which the emerging discipline was expressly identified by the SYMPHOGRAPHY name. '''July 30, 2025 — Official Foundational Formalization''' On July 30, 2025, the developing framework reached its foundational formalization as GODSAUDITION™ SYMPHOGRAPHY™. The framework incorporated structural concepts involving arcs, interludes, transitions, nonlinear composition, emotional scoring, analytical mapping, narrative relationships, and cross-media composition. These dates represent separate events within the documented genesis of the discipline and are not interchangeable. == Core Definition == SYMPHOGRAPHY™ is a coherent interdisciplinary system through which relationships among different forms of information may be identified, organized, mapped, computed, interpreted, translated, and composed. The framework may operate across: * literature * music * visual art * cinema * narrative structure * geometry * spatial organization * semantics * philosophy * symbolic systems * dimensional analysis * emotional structures * temporal relationships * conceptual architecture * interdisciplinary research Rather than treating these domains as isolated practices, SYMPHOGRAPHY™ investigates the relationships that connect them. Narrative may therefore be examined structurally as score. Visual form may be interpreted as partition. Spatial relationships may be mapped as analytical coordinates. Patterns of language, sound, imagery, emotion, movement, structure, space, and time may be compared or translated across media. == GODSAUDITION™ SYMPHOGRAPHY™ == '''GODSAUDITION™ SYMPHOGRAPHY™''' identifies the originating creative and intellectual research house within which the SYMPHOGRAPHY™ system was conceived and developed. The relationship between GODSAUDITION™ and SYMPHOGRAPHY™ is foundational to the documented genesis of the discipline. The term SYMPHOGRAPHY™ is therefore used within this research framework to identify a structured body of concepts, methods, terminology, analytical procedures, compositional relationships, and research applications. The originating practitioner is identified within the framework as the '''Symphograph'''. == Methodological Structure == SYMPHOGRAPHY™ may employ combinations of: '''Observation''' - identifying structural, visual, linguistic, emotional, musical, spatial, or conceptual relationships. '''Registration''' - recording relevant variables, positions, sequences, patterns, or relationships. '''Mapping''' - organizing relationships spatially, graphically, symbolically, narratively, or conceptually. '''Comparison'''- examining correspondences, differences, repetitions, transformations, and relational patterns. '''Translation''' - converting information or structure from one medium or representational system into another. '''Computation''' - applying numerical, geometric, spatial, dimensional, or proportional relationships where relevant. '''Composition''' - reorganizing mapped or translated relationships into literary, musical, visual, spatial, cinematic, or interdisciplinary forms. '''Interpretation''' - examining the conceptual, philosophical, semantic, emotional, or structural significance of the resulting relationships. == Nonlinear Development == The discipline developed through interconnected creative and research activity rather than through a single linear sequence. Literature, music, visual art, philosophical inquiry, storytelling, geometry, spatial analysis, semantics, symbolic systems, and conceptual research influenced one another during its development. This nonlinear structure remains part of the methodology itself. A SYMPHOGRAPHIC investigation may begin in one medium and produce meaningful relationships in another. A literary structure may generate a spatial model. A geometric arrangement may inform musical composition. A semantic absence may become the subject of philosophical analysis. A narrative structure may be mapped as a visual or temporal system. == Formal Disciplinary Demarcation == Within the GODSAUDITION™ SYMPHOGRAPHY™ framework, SYMPHOGRAPHY™ requires substantive structural, literary, analytical, spatial, architectural, mathematical, semantic, compositional, or otherwise relational depth. The discipline is concerned with the identification and organization of relationships across defined variables and media. Within this framework, use of the word '''symphography''' alone does not establish participation in the GODSAUDITION™ SYMPHOGRAPHY™ discipline. The system is therefore distinguished from uses of similar terminology referring solely to decorative lettering, calligraffiti, graffiti classification, gestural abstraction, isolated visual aesthetics, or unrelated artistic practices. This distinction concerns the internal definition and methodology of the GODSAUDITION™ SYMPHOGRAPHY™ research framework. == Terminological Integrity == SYMPHOGRAPHY™ is designed as an expanding research architecture. Its vocabulary may continue to develop as additional concepts, variables, classifications, analytical instruments, methodologies, and applications are identified. Expansion does not require abandonment of the foundational definition. '''Development expands the structural framework; it does not replace its foundational meaning.''' The framework evolves. The vocabulary expands. The methodologies develop. The applications multiply. The research deepens. The core architecture remains connected to its documented genesis. == Related Research == Research developed within or in relation to the SYMPHOGRAPHY™ architecture includes concepts and projects such as: '''ENTROAPORIA™''' - a conceptual framework concerning semantic absence. '''Mountain String Theory''' - a computational and spatial research framework examining structural relationships that may be translated into musical string composition. '''HOMOAXIOMOGRAPHY™'''- research concerning dimensional architecture, spatial relationships, conceptual structures, symbolic representation, and human or Soul Architecture. '''Mythopoetology™''' - an interdisciplinary conceptual framework developed through relationships among mythology, poetics, narrative, symbolic systems, and interdisciplinary composition. Additional terminology and research areas continue to develop as part of the broader SYMPHOGRAPHY™ research architecture. == Research Applications == Potential and developing applications of SYMPHOGRAPHY™ include: * literary and narrative analysis * interdisciplinary composition * musical structure * visual mapping * spatial analysis * geometry * conceptual architecture * semantics * symbolic representation * cinematic sequencing * multidimensional composition * philosophical inquiry * artistic research * cross-media translation * comparative structural analysis The framework is intended to permit examination of relationships that may otherwise remain separated by conventional disciplinary boundaries. == Provenance and Research Record == The chronology, terminology, written materials, diagrams, research texts, compositional systems, analytical models, graphics, methodological structures, and original expressions developed within SYMPHOGRAPHY™ form part of the documented research record of GODSAUDITION™ SYMPHOGRAPHY™. The presently documented foundational chronology is: '''July 13, 2025''' - developmental beginning '''July 28, 2025''' - earliest presently recovered explicit written naming record '''July 30, 2025''' - foundational formalization of the named discipline Subsequent publications, websites, research texts, books, diagrams, and public documentation continue the provenance record of the framework. == Research Status == SYMPHOGRAPHY™ is an evolving original research system. This Wikiversity resource is intended to document its concepts, development, terminology, methodology, applications, and research questions openly as the framework continues to develop. Readers and researchers should distinguish between: * documentation of the framework itself, * original hypotheses and interpretations developed within the framework, * externally established scholarship cited in connection with individual research questions, and * subsequent independent analysis or criticism of the framework. == External Resources == '''GODSAUDITION™ SYMPHOGRAPHY™''' <nowiki>https://godsaudition.com/</nowiki> '''SYMPHOGRAPHY™''' <nowiki>https://symphography.com/</nowiki> '''G-Symphography™ Core Doctrine''' <nowiki>https://godsaudition.com/g-symphography%E2%84%A2-1</nowiki> kwpe8ilhyz01knod16hs7oubzawxnz1 2844916 2844915 2026-11-09T00:04:18Z GODSAUDITION SYMPHOGRAPHY 3114035 symbols 2844916 wikitext text/x-wiki = SYMPHOGRAPHY™ = '''SYMPHOGRAPHY™''' is an original interdisciplinary research framework developed through '''GODSAUDITION™ SYMPHOGRAPHY™''' for the investigation, mapping, comparison, translation, and composition of structural relationships across creative and analytical media. This Wikiversity resource documents the developing research architecture, terminology, methodology, chronology, and applications of SYMPHOGRAPHY™. The material presented here includes '''original research''' by GODSAUDITION™ SYMPHOGRAPHY™ and should be read as documentation of an evolving interdisciplinary system rather than as an established academic consensus. == Documented Genesis and Foundational Chronology == The development of SYMPHOGRAPHY™ occurred nonlinearly. Three dates distinguish the developmental beginning, the earliest presently recovered explicit written naming record, and the formal foundational establishment of the discipline. '''July 13, 2025 - Developmental Beginning''' The documented foundational writing period began on July 13, 2025, during an intensive period of literary, conceptual, artistic, musical, structural, and interdisciplinary creation. This period represents the developmental environment from which the architecture later named SYMPHOGRAPHY™ emerged. '''July 28, 2025 - Earliest Explicit Written Naming Record''' By July 28, 2025, the term '''SYMPHOGRAPHY''' and the designation '''GODSAUDITION™ SYMPHOGRAPHY™''' were explicitly documented in connection with the developing interdisciplinary framework. This is the earliest presently recovered written record in which the emerging discipline was expressly identified by the SYMPHOGRAPHY name. '''July 30, 2025 - Official Foundational Formalization''' On July 30, 2025, the developing framework reached its foundational formalization as GODSAUDITION™ SYMPHOGRAPHY™. The framework incorporated structural concepts involving arcs, interludes, transitions, nonlinear composition, emotional scoring, analytical mapping, narrative relationships, and cross-media composition. These dates represent separate events within the documented genesis of the discipline and are not interchangeable. == Core Definition == SYMPHOGRAPHY™ is a coherent interdisciplinary system through which relationships among different forms of information may be identified, organized, mapped, computed, interpreted, translated, and composed. The framework may operate across: * literature * music * visual art * cinema * narrative structure * geometry * spatial organization * semantics * philosophy * symbolic systems * dimensional analysis * emotional structures * temporal relationships * conceptual architecture * interdisciplinary research Rather than treating these domains as isolated practices, SYMPHOGRAPHY™ investigates the relationships that connect them. Narrative may therefore be examined structurally as score. Visual form may be interpreted as partition. Spatial relationships may be mapped as analytical coordinates. Patterns of language, sound, imagery, emotion, movement, structure, space, and time may be compared or translated across media. == GODSAUDITION™ SYMPHOGRAPHY™ == '''GODSAUDITION™ SYMPHOGRAPHY™''' identifies the originating creative and intellectual research house within which the SYMPHOGRAPHY™ system was conceived and developed. The relationship between GODSAUDITION™ and SYMPHOGRAPHY™ is foundational to the documented genesis of the discipline. The term SYMPHOGRAPHY™ is therefore used within this research framework to identify a structured body of concepts, methods, terminology, analytical procedures, compositional relationships, and research applications. The originating practitioner is identified within the framework as the '''Symphograph'''. == Methodological Structure == SYMPHOGRAPHY™ may employ combinations of: '''Observation''' - identifying structural, visual, linguistic, emotional, musical, spatial, or conceptual relationships. '''Registration''' - recording relevant variables, positions, sequences, patterns, or relationships. '''Mapping''' - organizing relationships spatially, graphically, symbolically, narratively, or conceptually. '''Comparison'''- examining correspondences, differences, repetitions, transformations, and relational patterns. '''Translation''' - converting information or structure from one medium or representational system into another. '''Computation''' - applying numerical, geometric, spatial, dimensional, or proportional relationships where relevant. '''Composition''' - reorganizing mapped or translated relationships into literary, musical, visual, spatial, cinematic, or interdisciplinary forms. '''Interpretation''' - examining the conceptual, philosophical, semantic, emotional, or structural significance of the resulting relationships. == Nonlinear Development == The discipline developed through interconnected creative and research activity rather than through a single linear sequence. Literature, music, visual art, philosophical inquiry, storytelling, geometry, spatial analysis, semantics, symbolic systems, and conceptual research influenced one another during its development. This nonlinear structure remains part of the methodology itself. A SYMPHOGRAPHIC investigation may begin in one medium and produce meaningful relationships in another. A literary structure may generate a spatial model. A geometric arrangement may inform musical composition. A semantic absence may become the subject of philosophical analysis. A narrative structure may be mapped as a visual or temporal system. == Formal Disciplinary Demarcation == Within the GODSAUDITION™ SYMPHOGRAPHY™ framework, SYMPHOGRAPHY™ requires substantive structural, literary, analytical, spatial, architectural, mathematical, semantic, compositional, or otherwise relational depth. The discipline is concerned with the identification and organization of relationships across defined variables and media. Within this framework, use of the word '''symphography''' alone does not establish participation in the GODSAUDITION™ SYMPHOGRAPHY™ discipline. The system is therefore distinguished from uses of similar terminology referring solely to decorative lettering, calligraffiti, graffiti classification, gestural abstraction, isolated visual aesthetics, or unrelated artistic practices. This distinction concerns the internal definition and methodology of the GODSAUDITION™ SYMPHOGRAPHY™ research framework. == Terminological Integrity == SYMPHOGRAPHY™ is designed as an expanding research architecture. Its vocabulary may continue to develop as additional concepts, variables, classifications, analytical instruments, methodologies, and applications are identified. Expansion does not require abandonment of the foundational definition. '''Development expands the structural framework; it does not replace its foundational meaning.''' The framework evolves. The vocabulary expands. The methodologies develop. The applications multiply. The research deepens. The core architecture remains connected to its documented genesis. == Related Research == Research developed within or in relation to the SYMPHOGRAPHY™ architecture includes concepts and projects such as: '''ENTROAPORIA™''' - a conceptual framework concerning semantic absence. '''Mountain String Theory''' - a computational and spatial research framework examining structural relationships that may be translated into musical string composition. '''HOMOAXIOMOGRAPHY™'''- research concerning dimensional architecture, spatial relationships, conceptual structures, symbolic representation, and human or Soul Architecture. '''Mythopoetology™''' - an interdisciplinary conceptual framework developed through relationships among mythology, poetics, narrative, symbolic systems, and interdisciplinary composition. Additional terminology and research areas continue to develop as part of the broader SYMPHOGRAPHY™ research architecture. == Research Applications == Potential and developing applications of SYMPHOGRAPHY™ include: * literary and narrative analysis * interdisciplinary composition * musical structure * visual mapping * spatial analysis * geometry * conceptual architecture * semantics * symbolic representation * cinematic sequencing * multidimensional composition * philosophical inquiry * artistic research * cross-media translation * comparative structural analysis The framework is intended to permit examination of relationships that may otherwise remain separated by conventional disciplinary boundaries. == Provenance and Research Record == The chronology, terminology, written materials, diagrams, research texts, compositional systems, analytical models, graphics, methodological structures, and original expressions developed within SYMPHOGRAPHY™ form part of the documented research record of GODSAUDITION™ SYMPHOGRAPHY™. The presently documented foundational chronology is: '''July 13, 2025''' - developmental beginning '''July 28, 2025''' - earliest presently recovered explicit written naming record '''July 30, 2025''' - foundational formalization of the named discipline Subsequent publications, websites, research texts, books, diagrams, and public documentation continue the provenance record of the framework. == Research Status == SYMPHOGRAPHY™ is an evolving original research system. This Wikiversity resource is intended to document its concepts, development, terminology, methodology, applications, and research questions openly as the framework continues to develop. Readers and researchers should distinguish between: * documentation of the framework itself, * original hypotheses and interpretations developed within the framework, * externally established scholarship cited in connection with individual research questions, and * subsequent independent analysis or criticism of the framework. == External Resources == '''GODSAUDITION™ SYMPHOGRAPHY™''' <nowiki>https://godsaudition.com/</nowiki> '''SYMPHOGRAPHY™''' <nowiki>https://symphography.com/</nowiki> '''G-Symphography™ Core Doctrine''' <nowiki>https://godsaudition.com/g-symphography%E2%84%A2-1</nowiki> 134b0wzlj4rklk4fvu2m557cbhsmpy7 0 332874 2844918 2026-11-09T00:22:38Z GODSAUDITION SYMPHOGRAPHY 3114035 Created page with "= GODSAUDITION™ SYMPHOGRAPHY™ = '''GODSAUDITION™ SYMPHOGRAPHY™''' is an American creative, interdisciplinary, philosophical, and research foundation established in '''2022'''. It functions as the originating creative and intellectual house within which the interdisciplinary system '''SYMPHOGRAPHY™''' was later conceived, named, developed, and formally systematized. This Wikiversity resource documents the development, structure, research activity, creative meth..." 2844918 wikitext text/x-wiki = GODSAUDITION™ SYMPHOGRAPHY™ = '''GODSAUDITION™ SYMPHOGRAPHY™''' is an American creative, interdisciplinary, philosophical, and research foundation established in '''2022'''. It functions as the originating creative and intellectual house within which the interdisciplinary system '''SYMPHOGRAPHY™''' was later conceived, named, developed, and formally systematized. This Wikiversity resource documents the development, structure, research activity, creative methodology, terminology, and related projects of GODSAUDITION™ SYMPHOGRAPHY™. Material presented here includes '''original research and first-party documentation''' by GODSAUDITION™ SYMPHOGRAPHY™ and should be understood as documentation of a developing creative and intellectual framework rather than established academic consensus. == Foundation == GODSAUDITION™ was established in '''2022''' as a multidisciplinary creative identity encompassing music, songwriting, literature, visual art, storytelling, conceptual development, research, and related creative practices. Over time, these activities increasingly converged rather than remaining separate disciplines. The resulting body of work developed through recurring relationships among: * literature * music * visual art * philosophy * narrative * semantics * spatial organization * geometry * cinematic structure * symbolic systems * emotional experience * interdisciplinary research * conceptual architecture This convergence eventually produced the research architecture later named '''SYMPHOGRAPHY™'''. == Relationship Between GODSAUDITION™ and SYMPHOGRAPHY™ == The terms '''GODSAUDITION™''' and '''SYMPHOGRAPHY™''' describe related but distinct components of the same originating creative and intellectual structure. '''GODSAUDITION™''' identifies the originating multidisciplinary creator, creative identity, and body of work. '''SYMPHOGRAPHY™''' identifies the interdisciplinary research and compositional system developed through that body of work. '''GODSAUDITION™ SYMPHOGRAPHY™''' identifies the unified creative and intellectual house through which the system, its terminology, research frameworks, publications, and related concepts are developed. The relationship is therefore foundational rather than incidental. SYMPHOGRAPHY™ did not emerge as an isolated term detached from the broader GODSAUDITION™ creative practice. It developed through the convergence of previously existing literary, musical, visual, philosophical, narrative, and analytical work. == Development of SYMPHOGRAPHY™ == The formal emergence of SYMPHOGRAPHY™ occurred during an intensive period of interdisciplinary development in '''July 2025'''. The presently documented chronology distinguishes three stages: '''July 13, 2025: Developmental Beginning''' An intensive foundational writing and creative-development period began, bringing together literary, conceptual, artistic, musical, structural, and interdisciplinary work. '''July 28, 2025: Earliest Explicit Written Naming Record''' By July 28, the term '''SYMPHOGRAPHY''' and the designation '''GODSAUDITION™ SYMPHOGRAPHY™''' were explicitly documented in connection with the developing interdisciplinary system. '''July 30, 2025: Foundational Formalization''' The developing system reached its formal foundational articulation as a named interdisciplinary framework involving structural relationships, nonlinear composition, narrative architecture, arcs, interludes, transitions, emotional scoring, mapping, and cross-media analysis. The development of SYMPHOGRAPHY™ therefore represents an expansion of the GODSAUDITION™ creative foundation rather than the beginning of GODSAUDITION™ itself. == Creative and Intellectual Architecture == GODSAUDITION™ SYMPHOGRAPHY™ operates through the principle that creative and analytical disciplines may contain structural relationships capable of being examined across media. A literary work may possess musical structure. A musical composition may contain spatial relationships. A visual work may function as a symbolic or narrative map. A story may be organized through arcs, transitions, emotional scores, temporal patterns, or spatial structures. Language may contain relationships that can be examined visually, semantically, structurally, or philosophically. The system therefore investigates not merely individual works, but the relationships operating within and between them. == Interdisciplinary Practice == The creative and research practice of GODSAUDITION™ SYMPHOGRAPHY™ may involve combinations of: * songwriting * musical composition * literature * poetry * visual art * storytelling * cinematic development * philosophical inquiry * independent research * semantic analysis * spatial analysis * geometry * dimensional concepts * symbolic representation * conceptual architecture * interdisciplinary mapping These practices may operate independently, but within the SYMPHOGRAPHY™ framework they may also function as interconnected components of a larger structural composition. == The Symphograph == Within the framework, a practitioner of SYMPHOGRAPHY™ is identified as a '''Symphograph'''. The originating Symphograph is '''GODSAUDITION™''', through whom the named framework, its foundational architecture, terminology, classifications, and developing methodology were established. The Symphograph may investigate relationships across multiple forms of information and may translate those relationships between media. A Symphograph may therefore function simultaneously through literary, musical, visual, spatial, philosophical, analytical, or compositional processes depending upon the research question or creative work being examined. == Creative Research Roles == Within the broader GODSAUDITION™ SYMPHOGRAPHY™ framework, several descriptive creative-research roles have been used to express different aspects of interdisciplinary practice. These include: '''Philosophical Researcher''': investigating conceptual, ethical, semantic, existential, and structural questions. '''Mathematical Multidimensional Artist''': using mathematical, geometric, dimensional, proportional, or spatial relationships as artistic and conceptual materials. This designation is used as a creative and conceptual descriptor rather than as a professional mathematics credential. '''Lyrical Painter''': treating language and lyric as visual, emotional, and compositional material. '''Sonic Scribe''': treating sound, music, and songwriting as forms of inscription and narrative communication. '''Cinematic Storyteller''': developing narrative through visual sequencing, temporal structure, scene architecture, and cinematic relationships. '''Symphograph''': investigating and composing relationships across disciplines through the SYMPHOGRAPHY™ framework. These descriptions are not intended as rigid professional categories. They identify recurring functions within an interdisciplinary creative practice. == Research Methodology == GODSAUDITION™ SYMPHOGRAPHY™ employs an evolving methodology concerned with structural relationships. Research may involve: '''Observation''': identifying patterns, structures, variables, or relationships. '''Documentation''': recording the relevant creative, analytical, spatial, semantic, musical, narrative, or conceptual information. '''Mapping''': representing relationships spatially, graphically, symbolically, or conceptually. '''Comparison''': examining similarities, differences, repetitions, transformations, and correspondences. '''Translation''': moving a structure or relationship from one representational system into another. '''Computation''': applying mathematical, proportional, geometric, spatial, or dimensional relationships where appropriate. '''Composition''': reorganizing relationships into new literary, musical, visual, spatial, cinematic, or interdisciplinary forms. '''Interpretation''': examining what those relationships may reveal conceptually, structurally, emotionally, philosophically, or semantically. == Nonlinear Development == A central characteristic of GODSAUDITION™ SYMPHOGRAPHY™ is nonlinear development. Ideas may emerge in one work and become fully articulated in another. A concept introduced through literature may later become a research framework. A musical relationship may produce a spatial hypothesis. A visual structure may lead to philosophical inquiry. A narrative question may produce new terminology. Earlier creative works may therefore acquire additional analytical significance as later research frameworks reveal relationships that were not initially named. The interconnected nature of the creative catalog is consequently part of the research architecture itself. == Research Areas == Research developed through GODSAUDITION™ SYMPHOGRAPHY™ includes multiple emerging areas and named frameworks. === SYMPHOGRAPHY™ === SYMPHOGRAPHY™ is the central interdisciplinary system for investigating, mapping, translating, computing, comparing, interpreting, and composing structural relationships across creative and analytical media. === Semantic Density === '''Semantic Density''' is the concentration, accumulation, and interconnected depth of meaning within the SYMPHOGRAPHY™ framework. It develops as language, symbols, narrative, memory, knowledge, emotion, sound, imagery, spatial relationships, dimensional structures, research, and other forms of information become increasingly connected within an orchestrated whole. Semantic Density is not simply the presence of many meanings. It concerns the structural interconnection of those meanings: how one element refers to, strengthens, alters, echoes, or transforms another across a larger composition. Meaning may therefore accumulate word by word, page by page, image by image, sound by sound, and structure by structure until a work develops a highly concentrated semantic architecture in which very little exists independently of the relationships surrounding it. Within SYMPHOGRAPHY™, Semantic Density may be examined through the mapping of references, symbols, recurring motifs, narrative connections, emotional structures, spatial relationships, interdisciplinary associations, and other forms of semantic interdependence. The resulting density may extend across a single work or across multiple works, media, disciplines, and periods of development. === ENTROAPORIA™ === '''ENTROAPORIA™''' is a conceptual framework concerning '''semantic absence, nullification, indeterminacy, referential emptiness, semantic vacancy, and the disruption or refusal of compulsory semantic resolution'''. ENTROAPORIA™ does not merely describe a work containing less meaning. It concerns conditions in which semantic infrastructure may be removed, nullified, withheld, disconnected, flattened, rendered indeterminate, or prevented from reaching a compulsory interpretive destination. A central principle of ENTROAPORIA™ is that '''semantics must exist in order for semantics to be nullified'''. Nullification therefore represents a transformation of an existing or expected semantic condition. Material may remain physically, visually, linguistically, sonically, or structurally present while its stable semantic identity, referential certainty, encoded emotional trajectory, narrative destination, or required interpretive resolution is disrupted or voided. Within this framework, ENTROAPORIA™ may involve conditions such as: * semantic nullification * semantic flatline * referential emptiness * semantic vacancy * indeterminacy * unresolved destination * absence of compulsory emotional or narrative resolution * disruption of stable reference * refusal of predetermined semantic infrastructure * material presence accompanied by semantic absence * the silent score of nullification The relationship between Semantic Density and ENTROAPORIA™ is therefore not one of simple mathematical opposition or equivalence. '''Semantic Density develops interconnected semantic architecture, while ENTROAPORIA™ examines the nullification, absence, disruption, or suspension of semantic architecture.''' Within the framework, this distinction may be expressed through a '''Law of Non-Equivalence''': the semantic architecture produced through SYMPHOGRAPHY™ is not equivalent to the nullified or unresolved semantic condition examined through ENTROAPORIA™. ENTROAPORIA™ therefore occupies what may be described as '''the dead end of semantic completion, the world of nullification''', where the expectation of resolved meaning encounters absence, vacancy, interruption, indeterminacy, or refusal. === G-Symphography™ Core Architecture === '''G-Symphography™''' is the core architectural framework operating within the broader SYMPHOGRAPHY™ discipline. Within the established structure: '''GODSAUDITION™ is the House.''' '''SYMPHOGRAPHY™ is the discipline.''' '''G-Symphography™ is the core architecture.''' G-Symphography™ provides the structural environment through which relationships may be identified, organized, graphed, mapped, translated, compared, interpreted, analyzed, and composed across variables, disciplines, dimensions, and media. Its function is architectural rather than merely stylistic. It provides a relational framework through which literary, musical, visual, spatial, semantic, symbolic, emotional, temporal, mathematical, philosophical, and interdisciplinary information may be positioned in relation to other information. Within this architecture, the significance of an element is not necessarily limited to its isolated form. Meaning may arise from placement, sequence, recurrence, distance, direction, contrast, absence, density, resonance, transformation, and relationship. G-Symphography™ therefore operates as a structural core through which the broader methodologies and specialized systems of SYMPHOGRAPHY™ may be developed and applied. === Mountain String Theory === '''Mountain String Theory''' is a computational and spatial research framework developed within SYMPHOGRAPHY™ that investigates how measurable structural relationships derived from visual landscape form may be translated into musical string composition. The research establishes the visual source as more than thematic inspiration. Spatial and geometric information contained within a source form may participate directly in the development of musical structure through controlled computational translation. The first documented Mountain String research examined a measured two-dimensional landscape representation and translated selected spatial relationships into a one-dimensionally ordered musical composition. Mountain String Theory therefore demonstrates a central SYMPHOGRAPHIC principle: '''the structure of one medium may become compositional information within another while retaining a traceable relationship to its source.''' The detailed calculations, mapping procedures, computational rules, musical-event generation, notation systems, diagrams, and operational methodology are reserved for the corresponding GODSAUDITION™ SYMPHOGRAPHY™ research publications and doctrine. === HOMOAXIOMOGRAPHY™ === '''HOMOAXIOMOGRAPHY™''' concerns dimensional architecture, spatial relationships, conceptual structures, symbolic representation, and questions associated with human and Soul Architecture. Its complete methodological and analytical architecture remains documented within the corresponding GODSAUDITION™ SYMPHOGRAPHY™ research materials. === Mythopoetology™ === '''Mythopoetology™''' is an interdisciplinary conceptual framework involving relationships among mythology, poetics, narrative systems, symbolism, and creative composition. Its complete definitions, internal structures, and methodologies remain documented within the corresponding research and publication record. == Named Systems and Research Frameworks == GODSAUDITION™ SYMPHOGRAPHY™ includes a developing body of named systems, doctrines, research frameworks, analytical structures, and compositional models. These include: * '''G-Symphography™''' * '''Semantic Density''' * '''ENTROAPORIA™''' * '''Mountain String Theory''' * '''HOMOAXIOMOGRAPHY™''' * '''Mythopoetology™''' * '''Triple S™ / Sonic Symphographic Score™''' * '''S-Matrix''' * '''Golden Arc''' * '''Y-Axis''' * '''Nexus/Core models''' * '''Semantic Architectures''' * '''ASTRONEUROLOGY''' The names are presented here as part of the documented architecture and continuing research record of GODSAUDITION™ SYMPHOGRAPHY™. Their complete definitions, methodologies, internal structures, applications, diagrams, analytical procedures, computational rules, and operational relationships are reserved for the relevant doctrines, research publications, books, and official GODSAUDITION™ SYMPHOGRAPHY™ materials. == Literature and Narrative Research == Literature occupies a significant position within GODSAUDITION™ SYMPHOGRAPHY™. Narratives may be examined not only through plot and character, but through: * structural arcs * interruptions * recurrence * emotional movement * nonlinear sequencing * symbolic relationships * unresolved connections * temporal displacement * intertextual relationships * transitions * narrative resonance Within this framework, a story may be considered structurally analogous to a musical score. Characters, scenes, motifs, spaces, objects, memories, sounds, and emotional events may function relationally across a larger narrative composition. == Music and Sonic Research == Music and songwriting contributed significantly to the development of the broader framework. Research may consider: * rhythm * melody * lyrical structure * repetition * silence * emotional resonance * spatial relationships * timing * interval * sequence * compositional geometry * translation between visual or spatial structure and sound Music may therefore function both as an artistic medium and as a model through which relationships in other disciplines can be understood. == Visual and Spatial Research == Visual and spatial research within GODSAUDITION™ SYMPHOGRAPHY™ may involve: * geometric relationships * dimensional structures * visual mapping * architectural relationships * proportion * coordinates * partitions * axes * movement through space * symbolic geometry * compositional positioning These structures may subsequently be translated into music, narrative, diagrams, conceptual models, or other forms of representation. == Semantics and Conceptual Research == Language is treated as both communicative material and structural information. Research may examine: * meaning * semantic absence * semantic density * semantic nullification * referential emptiness * indeterminacy * newly developed terminology * neology * conceptual classification * relationships between words and structures * symbolic language * narrative meaning * ambiguity * conceptual boundaries * interdisciplinary translation New terminology may be introduced when existing vocabulary does not adequately identify an observed relationship within the developing framework. == Terminological Development == The vocabulary of GODSAUDITION™ SYMPHOGRAPHY™ is cumulative. New terms may identify previously unnamed: * relationships * processes * structures * classifications * analytical tools * conceptual states * research questions * compositional methods * applications The introduction of new terminology is therefore treated as expansion of the research architecture rather than replacement of its foundational structure. '''The framework evolves.''' '''The vocabulary expands.''' '''The methodologies develop.''' '''The applications multiply.''' '''The research deepens.''' == Publications and Documentation == The developing research architecture is documented through books, research texts, creative publications, websites, diagrams, music, visual works, narrative projects, and other public materials produced through GODSAUDITION™ SYMPHOGRAPHY™. The publication record serves both creative and provenance functions by documenting the chronology through which concepts, terminology, methods, and related frameworks developed. Individual publications may document specific research areas while remaining part of the broader interdisciplinary architecture. Detailed operational methods, formulas, diagrams, internal models, computational systems, analytical procedures, and complete doctrinal structures remain within the corresponding publications and official research materials. == Research Status == GODSAUDITION™ SYMPHOGRAPHY™ is an evolving independent creative and research framework. Material documented through this Wikiversity resource may include: * original research * first-party historical documentation * developing hypotheses * terminology * methodologies * conceptual models * creative applications * cited external scholarship where relevant Readers should distinguish between the internally documented structure of the framework and claims established independently through external scholarship. This public resource presents the general architecture, documented chronology, terminology, and principal research areas of GODSAUDITION™ SYMPHOGRAPHY™. It does not reproduce the complete operational architecture of the doctrines, research publications, analytical systems, formulas, diagrams, or protected creative materials. == Provenance == The chronology of GODSAUDITION™ SYMPHOGRAPHY™ distinguishes the establishment of the creative foundation from the later development of the named SYMPHOGRAPHY™ discipline. '''2022''': GODSAUDITION™ established. '''October 25, 2024''': GODSAUDITION™ YouTube presence established. '''July 13, 2025''': documented developmental period associated with the emergence of the later SYMPHOGRAPHY™ framework. '''July 28, 2025''': earliest presently recovered explicit written naming record of SYMPHOGRAPHY™. '''July 30, 2025''': foundational formalization of the named SYMPHOGRAPHY™ framework. The subsequent development of publications, terminology, research frameworks, compositional systems, and applications continues the documented history of GODSAUDITION™ SYMPHOGRAPHY™. == External Resources == '''GODSAUDITION™ SYMPHOGRAPHY™''' <nowiki>https://godsaudition.com/</nowiki> '''SYMPHOGRAPHY™''' <nowiki>https://symphography.com/</nowiki> '''G-Symphography™ Core Doctrine''' <nowiki>https://godsaudition.com/g-symphography%E2%84%A2-1</nowiki> == Related Wikiversity Resource == '''SYMPHOGRAPHY™''': the dedicated Wikiversity resource documenting the interdisciplinary system, its chronology, methodology, terminology, and developing research architecture. a0b98egj8o42lec805dmwksqxscycte 0 332875 2844932 2026-11-09T05:05:04Z ~2026-59286-66 3114046 Started a short learning-resource page explaining how an innings is recorded on a scorecard 2844932 wikitext text/x-wiki A scorecard is the written record of a cricket innings. Each batter's runs, balls faced and manner of dismissal are set out in turn, and a team's total is written as runs for the wickets lost, so that a total shown as 112/3 is read as 112 runs for three wickets.<ref>{{cite web |url=https://reddy-books.com/blog/how-to-read-a-cricket-scorecard/ |title=How to Read a Cricket Scorecard: A Complete Guide |website=Reddy Books |access-date=2026-11-09 |language=en-IN}}</ref> Extras such as wides and no-balls are added to the batting side's total and recorded separately from runs scored off the bat. ==See also== * [[Cricket]] [[Category:Cricket]] 7b1484tixkkfioq9p6i0um133v6x03p