Wikipedia talk:WikiProject Mathematics/Archive/2022/Aug

Weierstrass substitution → Tangent half-angle substitution

Just a heads up, since I know this came up a few times here before. I just restored Weierstrass substitution → Tangent half-angle substitution, after doing a fairly exhaustive search of old Calculus textbooks and other sources. Cf. Talk:Tangent half-angle substitution#Common name. I am now quite convinced that James Stewart was the source of this name (no other source before 1990 of the dozens I examined ever mentions Weierstrass in this context). Stewart’s (unsourced) claim that Karl Weierstrass originated/popularized this method is revealed by closer investigation to be clearly false (Euler first used it ~2 centuries before, and it was well known by Weierstrass’s time), but a few other authors in the 1990s took Stewart’s word for it and republished the claim uncritically, then it made its way into Mathworld and Wikipedia, whence it has spread widely. However, even today this remains minority usage (between them, descriptive terms like "tangent half-angle" and variants still outnumber "Weierstrass substitution" by at least 4:1 in recent academic literature, and the "Weierstrass" term didn’t exist at all in the pre-internet age). At some point in the indefinite future it’s possible the "Weierstrass substitution" name will proliferate to the extent it becomes commonly accepted throughout math/science/engineering; at that point Wikipedia can switch the name per WP:COMMONNAME. But today is not that day. –jacobolus (t) 01:14, 29 July 2022 (UTC)

I called this the "Weierstrass substitution", having learned that name from Stewart's book, in a very short publication in the American Mathematical Monthly, and Prof. Fred Rickey of the United States Military Academy at West Point wrote to me to say that that is a misnomer, and that he had thoroughly searched through Weierstrass's writings and had not found it, and that Euler had used this substitution in the 18th century. (Recall that Euler died some decades before Weierstrass was born.) I then sent an email to Steward asking about it. He replied that he was not the originator of the name, but he cited no earlier sources. I think he died shortly after that. Sone time after that, I sent an email to Rickey suggesting that he publish his findings. I never heard from him. Michael Hardy (talk) 06:10, 29 July 2022 (UTC)

Thanks for shedding more light here. I wonder where Stewart got that from. While you’re here Michael Hardy, I might mention that I started working on a draft of a more general article about the "half tangent" (that was the original name from the 17th–18th century but also has some currency in modern robotics and elsewhere; a.k.a. "semi-tangent" in the 18th–19th century, "half-angle tangent", "stereographic projection", many variations ...) in user namespace at User:Jacobolus/HalfTan. You might be interested in light of e.g. your AMM paper "Stereographic Trigonometric Identities". Right now I am mostly just gathering sources so the top part of the page there is not really reflective of what I am hoping to write (I haven’t yet started trying to make figures, structure sections, flesh out the history/applications, etc.) I wonder if you [or anyone else reading here] has any advice for sources to look at, esp. about historical sources, survey papers in fields where this is used regularly, etc. –jacobolus (t) 17:38, 29 July 2022 (UTC)

Ha ha.! :-) I think if we used Bayes' theorem we'd probably find that having something named after a mathematician is evidence somebody else discovered it first! NadVolum (talk) 10:08, 29 July 2022 (UTC)

Perhaps we're noticing Stigler's law of eponymy? Dicklyon (talk) 18:12, 29 July 2022 (UTC)

Thanks for that. NadVolum (talk) 23:46, 31 July 2022 (UTC)

Here is the publication of mine that I mentioned above: Hardy, Michael (2013). "Efficiency in Antidifferentiation of the Secant Function". The American Mathematical Monthly. 120 (6): 580. doi:10.4169/amer.math.monthly.120.06.580.
There I used the following variant of the tangent half-angle substitution:

$x={}\underbrace {\tan \left({\frac {\pi }{4}}+{\frac {\theta }{2}}\right)=\tan \theta +\sec \theta } _{\left({\begin{array}{l}{\text{Privately I think of this as}}\\{\text{the ``cartographers' tangent }}\\{\text{half-angle formula.''}}\end{array}}\right)}$

which leads to

$\sin \theta ={\frac {x^{2}-1}{x^{2}+1}},\quad \cos \theta ={\frac {2x}{x^{2}+1}},\quad d\theta ={\frac {2\,dx}{x^{2}+1}}$

and then to

$\int \sec \theta \,d\theta =\int {\frac {dx}{x}}.$

Is this variant worth mentioning in the article? Michael Hardy (talk) 18:59, 31 July 2022 (UTC)

Yes, if you explain how you derive the formulas. JRSpriggs (talk) 20:28, 31 July 2022 (UTC)

Yes, the stereographic projections from all 4 cardinal points are worth mentioning (cf. User:Jacobolus/HalfTan#Supplement and complement half-tangents). It’s also worth discussing branch cuts and other discontinuities resulting from such integrals, and possible ways of making integrals continuous (https://dl.acm.org/doi/pdf/10.1145/174603.174409 https://www.maa.org/sites/default/files/0025570x43754.di021186.02p0083t.pdf). (Though perhaps further discussion should be moved to talk: Tangent half-angle substitution.) –jacobolus (t) 16:07, 1 August 2022 (UTC)

is there any way to access NCTM journals without being an NCTM member?

Every once in a while in researching elementary-ish mathematical subjects I come across interesting looking paper titles in literature searches (or citations from other papers) in NCTM (current or former) journals, e.g. in The Mathematics Teacher. But it seems the only way to access these as an individual is to pay $150/year for an NCTM membership. Does anyone here know of alternatives? (This has come up several times in the past few months, but the specific paper I was curious about just now is Garfunkel & Leeds (1966) "The Circle of Unit Diameter"; just a one-sentence teaser isn’t enough information to assess whether there’s anything relevant in there though.) –jacobolus (t) 05:02, 8 August 2022 (UTC)

To answer my own question, they are apparently on JSTOR. Accessible from wikipedialibrary.wmflabs.org. –jacobolus (t) 05:43, 8 August 2022 (UTC)

Deleted drafts and the list thereof

At Wikipedia:Articles for deletion/Schneider's sine approximation formula, David Eppstein, XOR'easter, and I agreed that if drafts on Wikipedia:WikiProject Mathematics/List of math draft pages are deleted (usually because they were abandoned for 6 months), they should be removed from the list. Sometimes editors come by and do that, and TakuyaMurata typically reverts this. Taku will also often request undeletion for drafts that have been deleted just because they have been abandoned for 6 months. This means that if I want to get an incomplete draft out of an endless cycle of undeletion and re-deletion (which I think the three of us would argue goes against the consensus on how to use Draft: space), I either need to trim it enough to get it into article space, which seems to annoy editors with high standards, or it we need to have an affirmative deletion discussion. Many of the drafts stuck in this loop seem to be highly technical, and individual editors including some at Articles for Creation aren't necessarily able to discern whether the topic is worthy or the content is reasonable. This leads to the draft or trimmed down article being sent to a deletion discussion for discernment as the only way to get rid of it, which also annoys people for different reasons.

The practice of keeping redlinks and of undeletion was previously discussed at Wikipedia talk:WikiProject Mathematics/List of math draft pages#Keep redlinks?, and we revisited that. Other than Taku and XOR'easter (who said they were reconsidering their "keep" vote), the only other "keep" vote on deletion discussion for this list was Felix QW, who said they use Category:Draft-Class mathematics articles instead. This category is available as an alternative that does not require manual pruning when a draft gets promoted or deleted, and which also has a much more comprehensive list of math-related drafts. (It could be divided into subcategories if people think that would be helpful for navigation.) Looking at the edit history, Taku is the only editor that seems to be using the list for drafts other than their own anymore, and is certainly the only editor who needs a list because they want to undelete other editors' abandoned drafts.

It sounds like instead of making some policy about how the list should be used with respect to deleted drafts, the proposed solution coming out of the "Keep redlinks?" discussion seems to be to redirect the list of math drafts to the category of math drafts, and ask Taku to keep any list of drafts they need for undeletion or personal prioritization in their own User: space. This would save other editors the overhead of trying to use a list which is full of links to things that aren't drafts anymore or that should have been deleted by default or that actually have been deleted and are thus unreadable; the overhead of pruning the list to try to make it useful; and the unpleasantness of getting reverted when they try.

David Eppstein suggested this is the correct forum to get consensus for implementing this, so here we are. Apologies if my summary did not adequately convey anyone's opinions; I hope folks will speak for themselves here since now they've all been pinged. What are your thoughts? -- Beland (talk) 02:01, 3 August 2022 (UTC)

Incidentally, there are also many threads in the WP:AN and WP:ANI archives on Taku's misbehavior with respect to drafts (search for TakuyaMurata). This is not a new problem. —David Eppstein (talk) 02:37, 3 August 2022 (UTC)

If people want to keep draft articles around indefinitely perhaps they should use their own user namespace? –jacobolus (t) 04:11, 3 August 2022 (UTC)

If it's labeled as a draft (with an AFC template) in userspace, then it's also subject to the six-month limit. But it's easy to keep partial and not-ready-for-mainspace draft-like material on your own computers offsite (I have roughly 100 of them on my laptop). So the insistance that they must be kept on-wiki, when they really only have one person working on them, baffles me. —David Eppstein (talk) 05:09, 3 August 2022 (UTC)

I already replied but, to repeat (for others), that’s against the spirit of Wiki: in Wiki-way of development, we always make incomplete materials public. This helps feedbacks and also, for example, avoid duplicate efforts. This is why userspace drafts are not preferable, since they are less visible. Anyway, your argument is simply an argument against the draftspace per se. —- Taku (talk) 05:14, 3 August 2022 (UTC)

Sort of, yes. My general feeling is that the draftspace should be avoided by good-faith and serious editors. It is mostly a honeypot used to direct spammers to create their spam somewhere relatively harmless where it can be more easily cordoned off and disposed of. It needs some attention because some worthwhile content from naive editors (or inappropriate draftifications of good article content) ends up there as well, and should be skimmed off, but that's not its main purpose. —David Eppstein (talk) 05:19, 3 August 2022 (UTC)

"that's not its main purpose". I (and the other advocates of the draftspace) obviously disagree. Anyway, all I am saying is that there is a reason for the draftspace. —- Taku (talk) 05:38, 3 August 2022 (UTC)

To jacobolus, there is an issue of ownership and copyright: most of the drafts in the list are not started by me. So, it is tricky and controversial to move them to my userspace. If I keep them in my computer (really my iPad), then the copyright info gets lost and that could be a problem. -- Taku (talk) 05:24, 3 August 2022 (UTC)

The copyright issue is the main reason I haven't moved the three drafts I've been keeping alive off-wiki. —David Eppstein (talk) 05:31, 3 August 2022 (UTC)

If I understand, to keep track of the edit history, you need to maintain a draft in Wikipedia. Maybe there is a way to keep the edit history off-site; but that’s tricky and more work (I don’t know how to do it easily). —- Taku (talk) 05:38, 3 August 2022 (UTC)

I concede the list is mainly maintained by me. I maintain that it shouldn’t just list all the math drafts; that’s what a category is for. Therefore, if the project prefers to keep the list in my userspace instead of the project space, I do not object that. It’s not too important for me where the list is placed. (In fact, I already have a list of Japan-related drafts in my user space). —- Taku (talk) 05:18, 3 August 2022 (UTC)

I like to use LaTeX or other special mathematical formating which is available to pages in Wikipedia. I am not aware of any way to get that functionality on my own computer or elsewhere. This is a major reason why I like to keep my writings in Wikipedia, even if not in the articles themselves. JRSpriggs (talk) 07:50, 3 August 2022 (UTC)

It relatively trivial to get MathJax to render maths formula in a local webpage. Just add

<script>
MathJax = {
  tex: {
    inlineMath: [['$', '$'], ['<math>', '</math>']]
  },
  svg: {
    fontCache: 'global'
  }
};
</script>
<script type="text/javascript" id="MathJax-script" async
  src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-svg.js">
</script>

to the start of a page should kind of work. You would need a local webserver like xampp for it to function. Getting other Wikitext formatting to work is much more of a problem.--Salix alba (talk): 08:52, 3 August 2022 (UTC)

I use preview in a local sandbox when I need it. That doesn't require actually storing anything on-wiki. —David Eppstein (talk) 16:21, 3 August 2022 (UTC)

Same here, most of the time. (Writing offline reduces distractions.) XOR'easter (talk) 19:17, 3 August 2022 (UTC)

Just some observations (not proposals). What David is suggesting sounds like a Nupedia model to me, which was not a wiki and editors are supposed to submit a complete article developed privately. That model didn’t work and as an experiment Wikipedia was introduced (the rest is history). The draftspace supports two models in a sense. One aspect is an AfC; like a Nupedia, especially one editor develops a draft and submit it to be reviewed and, if passed, promoted to mainspace. On the other hand, the draftspace is also a place to develop new materials for established editors, who can just move materials to mainspace when they are done.

Editing through a preview cannot store editor history and even only one editor is editing an article, the edit history is useful (to restore previous discarded materials, etc.) Also, it is not reasonable to ask to run a local website in order to develop an article. (Doesn’t work for me, for example, as I usually edit on an iPad.)

It seems clear that the draftspace should be reformed in some fashion (but not sure how). In any case, we got to work with the system we got right now. So, for example, a list like the one in question is one tool for that. — Taku (talk) 05:52, 4 August 2022 (UTC)

It's not especially difficult to write a preliminary version of an article in a form that can survive in article space rather than draft space, and then let the collaboration with other editors begin from that point. Draft space is unnecessary for article creation, and the draft/article creation process (especially the long wait for a reviewer and the lack of subject expertise of reviewers) makes it a hindrance rather than a constructive way to work. The fact that the draft fragments you so cherish are languishing without edits for more than six months and getting deleted should be a hint to you that the draft process is not working for you, either. —David Eppstein (talk) 06:31, 4 August 2022 (UTC)

Just one more response. Like I said above, there is a problem but we got to work with what we got. I think, given what we got, the process is working: we are still getting drafts promoted to mainspace and, without my and some others’ works, a lot of valuable works would have been lost. “hints” are that we need to understand that, as is current the case, the draftspace is an article creation process we got and we simply have to do our best to work with it. It is time for you to realize the draftspace is here to stay if you like it or not. —- Taku (talk) 06:25, 5 August 2022 (UTC)

OK, since Taku is not objecting to userifying, unless someone in the next two days objects or wants to tweak the details or beats me to it, I will:

• Move Wikipedia:WikiProject Mathematics/List of math draft pages to User:TakuyaMurata/List of math draft pages
• Put a redirect from Wikipedia:WikiProject Mathematics/List of math draft pages to Category:Draft-Class mathematics articles and clean up incoming links.

-- Beland (talk) 18:28, 4 August 2022 (UTC)

Ah, I think we should at least keep the link since there might be someone interested in the list. There is no rule that we can’t link a userspace page in the project space. Ditto for redirects. I mean how is making it less visible makes our work more productive. —- Taku (talk)

It would make the math WikiProject more productive because the list is not well-maintained, and incurs maintenance overhead for anyone who attempts to use it that the category does not, including perennial disputes over the removal of redlinks. The point of userifying it would be to disaffiliate it from the WikiProject, while keeping it visible to you because you actually use it. Linking to the category makes it more visible to other WikiProject participants, who seem to prefer it over the list. -- Beland (talk) 07:01, 5 August 2022 (UTC)

No one is forcing anyone to use the list. I disagree it is not well-maintained; the list is selective and categorized, this makes it more convenient for, for example, me. Especially if it is in the userspace, it incurs no maintenance cost on the project. I am only talking about keeping the link: why it is necessary to hide the existence of the list? At least you need a consensus for that. —- Taku (talk) 07:10, 5 August 2022 (UTC)

I mean, I am a member of the project and so my list cannot be completely divorced from the project. I get you prefer a category to a list: but that preference should not be forced. —- Taku (talk) 07:20, 5 August 2022 (UTC)

I for one am quite happy to have the list in projectspace. Precisely because there is a large number of drafts that are not worth much, it seems valuable to me if a member of this project puts together drafts (initiated by him and others) that contain material they consider potentially worth having. I am also fine with not wanting half-baked articles in the encyclopedia that lead to eventually unproductive deletion discussion when the material could be used in a better way, either by potentially incorporating it somewhere else or by expanding into a well-sourced article.

I have certainly worked on some of these in the past and they have certainly enriched the encyclopedia when they reached mainspace. Felix QW (talk) 07:44, 5 August 2022 (UTC)

Like I said above, a list like this is a tool to work on the draftspace: nothing more. It’s mainly maintained by me so it may make sense to put in my userspace. But there is no need to make it secret to the others. —- Taku (talk) 07:42, 5 August 2022 (UTC)

@TakuyaMurata: If we point project participants at a userspace list that has redlinks and links to drafts that have already been turned into articles (which is what I see on the current list every time I clean it), then we will waste their time suggesting drafts they can't or don't need to work on. If they try to update the list to make it more useful for their future selves or the next editor who comes along, their time will be wasted when they get reverted because of the redlink dispute.

@Felix QW: You wrote in February on Wikipedia:Miscellany for deletion/Wikipedia:WikiProject Mathematics/List of math draft pages that you personally used the category instead. Has that changed?

What about a compromise where this list is kept but red links are allowed to be removed on sight and won't be re-added unless they turn blue again? That would eliminate the main source of conflict and the reason drafts have been getting pushed into article space or XFD. Taku can keep a secret list of deleted drafts if he wants, but the Requests for undeletion editors can also complain if the same draft is being undeleted several times, or decline an undeletion request if that keeps happening. It sounds like multiple undeletions will happen less often in the future because people have already done a lot of complaining, and the number of drafts stuck in this cycle is dwindling? Not sure how David Eppstein and XOR'easter feel about such a compromise. -- Beland (talk) 01:58, 6 August 2022 (UTC)

I wouldn't say it changed in that I now use it regularly, but since the last AfD brought the list to my attention I have looked over it to see if there is anything there which matches my interests or expertise. At any rate, I am very busy with real-life academic commitments over the last weeks and the foreseeable future, so I will probably not be using Wikipedia regularly, let alone a list of drafts... Felix QW (talk) 08:29, 6 August 2022 (UTC)

Either red links should be removed, or they need to be clearly marked with the reason for their deletion. I think the former is simpler. Either way, having to play a guessing game about what is listed and why makes the list counterproductive. I mean, it's way, way down the list of time-wasting things even just on Wikipedia, but still, creating the false impression that there's a community working on a draft or actively wanting to keep it around just leads to weird little squabbles that we could do without. XOR'easter (talk) 18:06, 6 August 2022 (UTC)

I thought we are discussing red links due to G13, automatic deletion of 6 month inactive drafts. If the deletion is due to MfD, say, then obviously the red links should be removed as not needed. Also, I don’t think the list gives a false impression. Perhaps it should be clarified but the list should only include drafts that the project think are worth working on, not mere fact it is math-related. So, there is only one reason and is really no guessing game. —- Taku (talk) 05:07, 7 August 2022 (UTC)

I can agree to remove red links as a compromise if the other members prefer that way. I didn’t know keeping red links is controversial (and those links are still in old revisions anyway so the links are not really gone.) —- Taku (talk) 07:12, 6 August 2022 (UTC)

Great. There was one redlink on the list today, so I deleted it. Can we consider this solved? -- Beland (talk) 06:52, 8 August 2022 (UTC)

Oh, and I changed the instruction on the list page that said not to remove red links; it now just says "Remove red links." -- Beland (talk) 06:56, 8 August 2022 (UTC)

"Vertex (topography)" listed at Redirects for discussion

An editor has identified a potential problem with the redirect Vertex (topography) and has thus listed it for discussion. This discussion will occur at Wikipedia:Redirects for discussion/Log/2022 August 8#Vertex (topography) until a consensus is reached, and readers of this page are welcome to contribute to the discussion. Shhhnotsoloud (talk) 11:46, 8 August 2022 (UTC)

By the way, Triangulated irregular network (target of the above redirect) seems related to Simplicial complex but does not mention it. JRSpriggs (talk) 14:24, 8 August 2022 (UTC)

A TIN is of course a very specific kind of simplicial complex, but simplicial complex is a much more general type of object. More closely relevant articles include triangulation (geometry), polygon triangulation, surface triangulation, point-set triangulation triangulation (topology), Delaunay triangulation, triangle mesh, chordal graph. –jacobolus (t) 23:19, 9 August 2022 (UTC)

Construction animations

I have produced these animations to replace two of the images on the Straightedge and compass construction page - the first one was only intended to be demo (according to the original author) and the second was an overly convoluted construction according to some Wikipedians. Can anyone give me some feedback on these before I add them to the article, and can anyone suggest any other articles which might benefit from animations like these?

Basic constructions animation with labels

A straightedge-and-compass construction of a pentagon

Spiritual Directive (talk) 20:19, 4 August 2022 (UTC)

While I like animations in general, I don't think they should be added to Wikipedia articles. They distract from the text (cf. Motion perception), which can be annoying in particluar when I have to try hard to understand the text. However, this may be a matter of personal taste. - Jochen Burghardt (talk) 08:48, 5 August 2022 (UTC)

I think it's certainly a matter of topic, which is why I started with geometry/constructions. Spiritual Directive (talk) 13:47, 5 August 2022 (UTC)

Nice production value! What did you use to make it? Since you asked for feedback, here are some comments, which I hope are... constructive :)

• I think it would be more useful if the pentagon animation was less eager about erasing. The more important lines that are used in intermediate stages should stay visible for most of the time (at least until after the first edge of the pentagon is drawn). That is, we shouldn't erase them all immediately after they're no longer strictly needed for later steps. The minor details should still be erased immediately once they've served their purpose. If you're not sure how to decide what parts to keep visible and what to erase as you go, imagine what an uncluttered non-animated diagram of the same construction would contain. Like this: [1] (not 100% the same as your construction; I just mean roughly this level of detail).
• I think it's more familiar to viewers to have points drawn as dots instead of as X shapes. (Also, there was one part I especially thought was unnecessarily distracting: near the beginning, where two points drawn as + shapes rotate to become X shapes. If the points were dots, this wouldn't have been a problem.)

Adumbrativus (talk) 09:16, 5 August 2022 (UTC)

Thank you for your feedback! I used Manim to make these.

• Yes, I understand what you mean about erasing things: the segment bisector can stay, but the construction lines can be erased once the bisector is drawn.
• Using dots has occurred to me, but I found it difficult to make them stand out against the lines - maybe all dots can be another colour to make them easier to see? Not sure whether adding too much colour will be distracting - I also considered making old circles and lines grey as new ones appear to indicate the current step. This is also helpful if the animation is playing as a video and the viewer decides to pause it.

I will probably reduce the thickness of the lines if I substitute the crosses for dots and erase construction lines a little less readily, maybe that might help, although I think I'll still need a different colour for the dots. Spiritual Directive (talk) 14:00, 5 August 2022 (UTC)

@Adumbrativus, XOR'easter, and JayBeeEll: I've updated the animation, using points instead of crosses and retaining some construction lines where I deemed necessary. I also added some more colours to try and help differentiate the lines from the points - I didn't want to decrease their thickness/size because the diagrams have to be visible at a small size too. I don't think I can do anything about the zooming though, because otherwise it's unclear where the large arcs/circles are coming from.

I didn't bother updating the thumbnail yet, but you can click the old thumbnail beside this post to be taken to the new version of the file (there are no animated thumbnails for animations of this resolution, so you'll have to click on the gif again to view it on a separate page). Spiritual Directive (talk) 00:18, 10 August 2022 (UTC)

Your lovely animations are making me wish again that Wikipedia was not so completely incapable of rendering interactive content and multimedia in general. It would be really nice to have a version that could be clicked through step by step with description alongside, but Mediawiki sadly doesn’t have the tools for producing/rendering such a thing. –jacobolus (t) 10:31, 5 August 2022 (UTC)

Thank you! I think WebMs are decent for things like animations, but yeah, I wish there was a way to upload multiple versions of the same diagram/animation without just linking to different files in 'other versions'. Uploading is also a pain in that regard... Spiritual Directive (talk) 14:03, 5 August 2022 (UTC)

I agree with Adumbrativus's comments. I also found some of the abrupt zooming in and out to be distracting & in some cases disorienting. --JBL (talk) 18:04, 5 August 2022 (UTC)

Same here. This is a good start (and a good use of Manim), though. XOR'easter (talk) 17:53, 6 August 2022 (UTC)

Watch out for the file size on those gifs, because as of writing this your example is at 32.5 MB (6x higher than originally, and definitely not publishable). Depending on the tools you're using, you could address issues of both file size and motion distraction if you either used video files instead (which only load if the user clicks on them), or alternatively an interactive SVG (the latter is used for some circuits). Fwiw I liked the crosses over the dots just because that's sort of how the points would look if you were to actually construct them, but it's not a big deal. SamuelRiv (talk) 00:41, 10 August 2022 (UTC)

Thank you for the suggestion! I'll definitely upload a webm version - the large file size is just because I used the gif from Manim itself, rather than processing it myself with ffmpeg. Once I'm satisfied with the result I'll upload all 3 versions (gif, thumbnail gif and webm) properly. Spiritual Directive (talk) 01:41, 10 August 2022 (UTC)

Urysohn space vs. Urysohn universal space

Up until 8 Aug 2022 the page Urysohn space used to redirect to Urysohn and completely Hausdorff spaces (which covers the two concepts "Urysohn space" and "completely Hausdorff space"). Then recently someone had the idea to replace the redirect with a disambiguation page, disambiguating between "Urysohn space" and Urysohn universal space. (And then some well-intentioned editor went on a spree editing a bunch of other articles trying to bypass that disambiguation page, but that's beside the point.) As far as I can tell, there is no need for this disambiguation page. The "Urysohn universal space" is always specified under that name, and "Urysohn space" refers to the topological property instead.

What I am asking here is what the recommended procedure would be to undo the disambiguation page (because there were two edits A and B on the disambiguation page). Should I just do an undo of B and then an undo of A, or something else to get back to the previous state in one shot? PatrickR2 (talk) 04:11, 10 August 2022 (UTC)

You can just change the content back to #redirect [[Urysohn and completely Hausdorff spaces]] and if you want to be extra nice you can leave a message at the user talk page of Tosha who changed it. –jacobolus (t) 04:33, 10 August 2022 (UTC)

Thanks. I already left a message for Tosha on the talk page of the page. So I'll just change the contents directly then. PatrickR2 (talk) 05:53, 10 August 2022 (UTC)

Arthur Rubin

There’s been a few comments on the page Arthur Rubin regarding whether he’s actually notable enough to warrant an article. As far as I can tell his only significant accomplishment is being one of the only four-time Putnam Fellows. My feeling is that that alone probably wouldn’t make him notable, and the article should be deleted, but I figure folks here might have a more informed opinion. Thoughts? Isomorphic (talk) 15:36, 9 August 2022 (UTC)

I think some personal value judgment is unavoidable; some people find awards/competitions like Putnam and IMO to be significant, others (myself included) don't. It seems about half of the eight Putnam fellows have had notable careers, half have had basically ordinary ones. If it were up to me only the first half would have pages but I think enough people find Putnam excellence to be important/significant that it's ok to keep pages for the other half also. Gumshoe2 (talk) 17:22, 9 August 2022 (UTC)

Please review Wikipedia:Articles_for_deletion/Arthur_Rubin_(6th_nomination) before moving forward. --JBL (talk) 17:37, 9 August 2022 (UTC)

In particular, please see David Eppstein's carefully-reasoned !vote there. Without having a horse in this race, I think it's fairly clear that the article should stay. - CRGreathouse (t | c) 15:08, 10 August 2022 (UTC)

Wikipages for highly notable math papers

I recently became aware of a small number of wikipages for specific math papers [2]. There are surely a decent number of equally important papers that could be added. However I could not find much relevant information/advice on wiki notability guideline pages; has the question of such notability been discussed somewhere? For example, would papers receiving the AMS Seminal Research award [3] be considered automatically notable enough for a page? (In my opinion this would be reasonable) Gumshoe2 (talk) 18:40, 6 August 2022 (UTC)

By the strict letter of the General Notability Guideline, thousands of papers probably qualify, just for getting significant follow-up in papers by other authors. But that goes to show that strict GNG fundamentalism is a little silly, more than anything else. When it comes to textbooks, we can write about them as books, because reviews cover things like their organization, intended audience, writing style, idiosyncratic choices of topics included or excluded, etc. I'm not sure how often we can do something like that for individual papers. My guess is that often, even for important papers, there isn't a lot to write in that regard, and so it makes more sense to cover them in biographies of their authors or in articles on the subject matter. For example, "The Sphere Packing Problem in Dimension 8" is an important paper, but I'd be inclined to write about it in the articles Maryna Viazovska and Sphere packing.

I do, however, confess a great sentimental fondness for the idea of articles on specific math papers, just like I have for articles on textbooks. XOR'easter (talk) 18:55, 6 August 2022 (UTC)

I agree. However I think paper-specific wiki pages give a natural opportunity to go in some greater depth than would be more appropriate than biography pages (where, at the least, pretty much any formulas whatsoever would be out of place) or more general-purpose pages (where content has to be balanced with all other material on the page). For instance Viazovska's paper (disregarding the question of whether it is notable enough for a standalone page) already occupies a dense paragraph on the sphere packing page which I think is already somewhat unbalanced relative to the rest of the page. Gumshoe2 (talk) 19:08, 6 August 2022 (UTC)

To spring back at you with a question: why would formulae be out of place in a biography of a mathematician? The Featured article Leonhard Euler has several, for example.

Perhaps the best thing to do is to write an example of the kind of article you have in mind. At worst, the result would probably be suitable for merging if people don't like it as a stand-alone. XOR'easter (talk) 19:16, 6 August 2022 (UTC)

Good suggestion!

I suppose formulas in principle can be ok (and I have even added some formulas to bio pages), but I think should be generally avoided if possible in the interest of accessibility. The formulas on the Euler page can be understood by anyone who has taken calculus, so by my own standards they are very minimal offenders. (Although one of them, in the music section, is a little inscrutable to me.) When it comes to more modern (last 50 years) works it is significantly harder to use formulas or symbols which are understandable by any remotely broad kind of audience. Gumshoe2 (talk) 19:24, 6 August 2022 (UTC)

True, although the verbal jargon is likely not much better! XOR'easter (talk) 19:58, 6 August 2022 (UTC)

My feeling is that for a paper to have an article, there should be something about it that stands out separately from the research that the paper presents, enough to make a standalone article on the paper rather than on the mathematics. Maybe there are publications about the paper and its history (not just about the mathematical results it presents), it won a major award, it has a particularly unusual publication history, something like that. But ultimately the real standard is: some Wikipedia editor feels strongly enough about it to write an article, and the sourcing is independent and in-depth enough for it to survive deletion attempts. —David Eppstein (talk) 20:08, 6 August 2022 (UTC)

I'm thinking along similar lines: what makes a paper encyclopedic in a manner that should justify an article separate from its subject and/or author? I can think of two definites offhand: The Spandrels of San Marco and the Panglossian Paradigm, and A Structure for Deoxyribose Nucleic Acid for the famously understated foreboding: "It has not escaped our notice...." There's plenty of seminal papers out there, but how many of them present a moment greater than themselves that is iconic in this way?

Of the math-related papers I know offhand there's famously "In this paper, we present Google" (arguably performative, no more meaningful than what's on the tin), and Ramanujan has famously indecipherable papers which skip way too many steps (but is there a single iconic one?). James Gleick accused Newton in his bio of faking the experiment in his monograph on the visible spectrum, among others. I can think of clever jokes in titles, abstracts, and authors of some notable papers, but they do of course still have to be notable. Also there's iconic articles related to weapons tech and censorship, such as Morland's in The Progressive; I vividly remember the first time I saw dimensional analysis demonstrated on photos of the Trinity Test, and went looking for the original paper, but also found the popular story is riddled with myth. SamuelRiv (talk) 21:57, 6 August 2022 (UTC)

I just want to point out we have articles on mathematical manuscripts; e.g., Esquisse d'un Programme and Pursuing Stacks. So, it seems math papers should be treated similarly. I would argue that Grothendieck's Tohoku paper or Hironaka's paper on the resolution of singularities, or Mochizuki's (in?)famous papers on abc conjecture are surely of encyclopedic interests. -- Taku (talk) 08:09, 7 August 2022 (UTC)

I didn’t answer the original question. I think these articles can be handled case-by-case, as there are not many. —- Taku (talk) 19:48, 7 August 2022 (UTC)

Regarding the list of papers currently under Category:Mathematics_papers [4] it seems that one of them should probably removed from there and migrated to Category:Biology_papers [5], namely The Chemical Basis of Morphogenesis. It was written by Alan Turing, and it does use mathematics, but it seems the main purpose and contents of the paper is about biology/chemistry. Papers from other sciences routinely make use of mathematics, but that does not make them primarily mathematics papers, in the same way that not every paper written by Newton or Gauss is necessarily a mathematics paper. PatrickR2 (talk) 03:13, 8 August 2022 (UTC)

The article doesn't really give a justification, either in prose or references, for why that paper should have its own article separate from what's covered in Alan Turing and Turing pattern.

Also in browsing around it I found a very longstanding unsourced animation, if someone is familiar with the topic: Talk:Belousov–Zhabotinsky_reaction#12_years_an_orphaned_gif. SamuelRiv (talk) 04:35, 8 August 2022 (UTC)

I think it's arguable either way. It can be viewed as a paper on the theory of reaction-diffusion systems in partial differential equations, which happens to have some motivation from biology. (Or at least this is how I view it.) In my opinion it is more of a math paper than a biology paper, although the biological motivation is very interesting and strong. But I wouldn't argue if someone were to move it to the biology category. Gumshoe2 (talk) 04:43, 8 August 2022 (UTC)

Turing's paper is about the mathematical basis of pattern generation and therefore fits well as applied mathematics. Also it has huge citation counts and multiple sources specifically devoted to it as a publication, concerning its "its background, immediate reception and subsequent impact" (doi:10.1007/978-4-431-65958-7_3, doi:10.1007/978-3-642-70911-1_16, doi:10.1098/rstb.2014.0218, hdl:10776/2036, etc). So although the two articles as they stand don't clearly differentiate the publication and its background and impact from the patterns it describes and their subsequent development, I think there is clearly scope to do so. —David Eppstein (talk) 06:12, 8 August 2022 (UTC)

Sometimes books are produced which talk about specific papers or even reprint them. There's reprints in histories of maths and physics and economics and computing and even specific subjects like general relativity or quantum mechanics and there's lots in other subjects too. The ones that are reprinted definitely would qualify for having articles about them I'd have thought. NadVolum (talk) 09:31, 8 August 2022 (UTC)

I think merely being reprinted might not be a good reason to have a stand-alone article, because the mere fact of reprinting doesn't give us much more to write. But it is a signal of a paper's historical importance, and the prefaces to such collections may have information about their background and influence. XOR'easter (talk) 14:49, 8 August 2022 (UTC)

A Mathematical Theory of Communication is an example wiki article about a math paper. –jacobolus (t) 20:27, 8 August 2022 (UTC)

As soon as I read the initial posting above, I looked at the category and I did not find "Hearing the shape of a drum", so I went to that article and added the category. Moral of the story: This is, so far, incomplete. Maybe I'll start a list article for these. Or is there one already? Michael Hardy (talk) 22:18, 10 August 2022 (UTC)

. . . and now I've also added An Essay towards solving a Problem in the Doctrine of Chances. Michael Hardy (talk) 22:23, 10 August 2022 (UTC)

It's not so clear to me that Hearing the shape of a drum should be regarded as a page about Kac's article, as opposed to being about the topic of Kac's article. But I don't have a strong opinion Gumshoe2 (talk) 00:10, 11 August 2022 (UTC)

I agree that the subject of the article is broader than the paper introducing the subject, but if I were looking at that category I think this is indeed the sort of article I would be looking for, so I think the category is appropriate. - CRGreathouse (t | c) 03:18, 11 August 2022 (UTC)

That's a fair and convincing point Gumshoe2 (talk) 16:19, 11 August 2022 (UTC)

Suita conjecture

I am wearing my New Pages Patrol hat. I am requesting some editors from this project look at this recently created page and see if it qualifies for inclusion. I don't have the expertise in mathematics to determine anything about this topic. Do the references support this as a topic? Thanks in advance for any help. ---Steve Quinn (talk) 23:26, 17 August 2022 (UTC)

The classical Suita conjecture, a conjecture related to open Riemann surfaces, but technique of the L² extension theorem was used to prove it. So, I was wondering whether to create a separate article from the extension theorem, but since there seems to be a proof of the Suita conjecture that does not use the extension theorem, I decided to create a draft. --SilverMatsu (talk) 03:59, 18 August 2022 (UTC)

I have moved this draft to mainspace since the development of it seems complete (so no point to having it in the draftspace). One potential issue I can see is that WP:TOOSOON; some references in the article are only a year or two old (it is not uncommon someone announces a result and but retracts it soon after). But the conjecture itself is sufficiently old so maybe it's ok. -- Taku (talk) 07:32, 18 August 2022 (UTC)

Thanks very much for your help. I have marked the article as reviewed (and with no issues). ---Steve Quinn (talk) 17:17, 18 August 2022 (UTC)

Create a shadow angle article

Hello dear users, the shadow angle is one of the important topics of mathematics. I suggest that an article on the shadow angle be made. What do you think? AHEJJWILEMAMALIDGED (talk) 08:22, 5 August 2022 (UTC)

Can you elaborate? It's not clear just what topic you have in mind. Michael Hardy (talk) 17:23, 5 August 2022 (UTC)

See, I suggest you create the Shadow angle because this topic does not exist in mathematics. AHEJJWILEMAMALIDGED (talk) 19:09, 5 August 2022 (UTC)

Your initial post is vague and cryptic. If you want anyone to help you, then instead of repeating the same vague and cryptic statement, you should explain more clearly what you are talking about. JBL (talk) 19:43, 5 August 2022 (UTC)

By “shadow angle” are you talking about the length of a shadow cast by a gnomon? For instance as seen in Al-Battani’s “shadow table” (in modern times called the “cotangent” function). –jacobolus (t) 20:14, 5 August 2022 (UTC)

Shadow angle(به فارسی:زاویه ظلی)It is an angle drawn in a circle,I suggested that we create this article.Because this topic did not exist in mathematics.Now I wanted to ask your opinion.Did you all understand? — Preceding unsigned comment added by AHEJJWILEMAMALIDGED (talk • contribs) 04:26, 6 August 2022 (UTC)

No. Try explaining rather than just repeating the name of the topic. —David Eppstein (talk) 05:52, 6 August 2022 (UTC)

Articles can only be created in Wikipedia if there are notable sources about the topic. This means at the very least we need some book or place on the web that talks about shadow angle before anythng can be done about the topic. Can you point to something like that? NadVolum (talk) 11:13, 6 August 2022 (UTC)

This topic is in the book wiki. AHEJJWILEMAMALIDGED (talk) 11:36, 6 August 2022 (UTC)

Found out what is happening. It seeming is a literal translation from Arabic, like talking about water sheep in hydraulics. [6] shows it as the angle A between a chord and a tangent. In fact I very possibly got the wrong illustration there - thinking about it they're probably thinking of the alternate segment theorem. NadVolum (talk) 13:34, 6 August 2022 (UTC)

I believe AHEJJWILEMAMALIDGED is talking about the page b:fa:ریاضیات_پیشرفته/زاویه_ظلی in the Farsi Wikibooks. I’m not sure there’s any specific name in English for the angle between a tangent and a chord, but I agree it would be a useful angle to give a name to. –jacobolus (t) 15:27, 6 August 2022 (UTC)

It's briefly mentioned at Inscribed angle and Tangent lines to circles, but offhand, I don't recall there being a name for it. XOR'easter (talk) 20:52, 6 August 2022 (UTC)

Besides inscribed angle, this is also relevant to bipolar coordinates, Apollonian circles, radical axis, and pencil of circles. But I am not sure it needs its own article. –jacobolus (t) 00:01, 7 August 2022 (UTC)

I'm now reminded of an interesting opinion I once read at User:Colin_M/soapbox: whether we have an article on a topic may be too greatly influenced by whether it has a name. And, to add to that, whether it has a name in English. Given that notability isn't (supposed to be) English-centric, the idea of "Sapir–Whorf notability" is a little unsettling. Not necessarily an opinion on this specific topic, just a general thought. Adumbrativus (talk) 00:55, 7 August 2022 (UTC)

This is of course true. Things that have clear and widely adopted names get used where appropriate under those names; things that don’t have clear or widely adopted names get ignored, written about under a mishmash of ad-hoc names which are often either obscure or cumbersome, or just used without being named. In all of these cases until a good name emerges, those concepts are held back because relevant results are hard to search for, hard to link together, and hard to develop a coherent and cohesive body of knowledge about. Same story for good notation. –jacobolus (t) 23:08, 9 August 2022 (UTC)

Since this topic is mentioned in the Persian book wiki, it is good to make this article as well AHEJJWILEMAMALIDGED (talk) 20:24, 6 August 2022 (UTC)

Why don't you add it to the Farsi wikipedia then? PatrickR2 (talk) 02:26, 8 August 2022 (UTC)

In my opinion, we should create it first, so that other wikipedias will create it later. AHEJJWILEMAMALIDGED (talk) 11:16, 9 August 2022 (UTC)

In searching I couldn’t find any use of the phrase “shadow angle” in English, except in the context of literal shadows (like the angle of the shadow in a photograph of a crater on the moon, or the angle of the shadow of a gnomon on a sundial). So it wouldn’t really make sense to add an English wikipedia article under the name shadow angle. I personally don’t think the angle between the tangent and chord is noteworthy enough for its own article, you could try adding more detail about it at inscribed angle if you want. –jacobolus (t) 13:20, 9 August 2022 (UTC)

Do we have a mathematician, fluent in both Farsi and English, who is willing to do the translation? If not, then this is all moot. JRSpriggs (talk) 21:57, 9 August 2022 (UTC)

I think this is an important issue. This topic has been brought up in the circle chapter of the 11th grade geometry book of mathematics and physics and the theorem has been proven. There are many different types of this angle, I'd say there's nothing wrong with creating it.what is your opinion? AHEJJWILEMAMALIDGED (talk) 05:26, 10 August 2022 (UTC)

You should go ahead and create the article on the Farsi Wikipedia, citing reliable sources written in Farsi. Nobody here is going to make an article about this on the English Wikipedia, because there are no relevant sources in English. If you like you can also add material to inscribed angle as long as it is encyclopedic and based on reliable sources. –jacobolus (t) 17:57, 10 August 2022 (UTC)

Thank you very much, I write this topic in this article. The issue is resolved. AHEJJWILEMAMALIDGED (talk) 19:12, 10 August 2022 (UTC)

Just to make things very clear, we told you to write this in the Farsi wikipedia, not in the English wikipedia. PatrickR2 (talk) 02:49, 12 August 2022 (UTC)

That means they accept my theory? AHEJJWILEMAMALIDGED (talk) 04:38, 12 August 2022 (UTC)

If you want to add something to inscribed angle it needs to be based on reliable sources. Those could plausibly be in Farsi, but Wikibooks doesn’t cut it. The ideal would be something like a scholarly article describing the history of the term "shadow angle". Then you could add to the section mentioning the angle between the chord and the tangent something like "In Farsi and Arabic the angle between a tangent and chord was named the "shadow angle" (word in Farsi) by astronomer ABC in the YZ century". –jacobolus (t) 04:48, 12 August 2022 (UTC)

In the name of of Allah the Merciful

Helllo.I read several articles in English about the shadow angle, but not much about the circle, and its content is about spherical coordinates and the aspect of applied mathematics in astronomy, and it also has generalization content. In terms of application, it deals with the sun, earth, eclipse, lunar eclipse, etc. If you want, I will post the contents of other sites. AHEJJWILEMAMALIDGED (talk) 08:13, 23 August 2022 (UTC)

Just to be clear, leave that contents in the other sites and don't import it to the English wikipedia. Any such attempt will be rejected, for reasons already explained above (and specifically the arguments provided by jacobolus). PatrickR2 (talk) 05:04, 1 September 2022 (UTC)

Creation of Fourier Series Integral Essay

Hello again, the subject of Fourier series integral is based on the combination of Fourier series and integral. In general, integration is based on Fourier series and its transformation. This topic is available in English and Farsi on Google. I recommend that this article be made. — Preceding unsigned comment added by AHEJJWILEMAMALIDGED (talk • contribs) 11:16, 11 August 2022 (UTC)

Please stop telling people to create articles. We are all volunteers here. We cannot not tell anyone to go and create an article just because we think it would be useful. PatrickR2 (talk) 02:51, 12 August 2022 (UTC)

No, I do not order, it is translated into this verb in the translation. AHEJJWILEMAMALIDGED (talk) 04:49, 12 August 2022 (UTC) Please reply to my text AHEJJWILEMAMALIDGED (talk) 12:46, 14 August 2022 (UTC)

We already have Fourier series, Fourier transform, Fourier analysis, and other pages. What are you suggesting we write? XOR'easter (talk) 20:10, 14 August 2022 (UTC)

See, my suggestion is to create a Fourier series integral. Fourier series integral is related to Fourier series and Fourier transform, Fourier analysis, etc., but this topic has a separate topic and integration of Fourier series and Fourier transform or a combination of these two topics. If this science is created, it will provide more information for the concepts of Fourier series and Fourier transform, etc., there is no problem in creating it. AHEJJWILEMAMALIDGED (talk) 05:31, 15 August 2022 (UTC)

Please list at least one English-language reliable source that treats the material in the way that you want. By doing so, you help us understand what you want, and you help us avoid original research. Mgnbar (talk) 13:26, 15 August 2022 (UTC)

At least how many English sources should we bring? AHEJJWILEMAMALIDGED (talk) 03:38, 16 August 2022 (UTC)

In the name of Allah

Hello, the topic of Fourier series integration can be included in the Fourier series article, and I have seen several sources of it, you can search. AHEJJWILEMAMALIDGED (talk) 08:32, 23 August 2022 (UTC)

We can't tell what you're talking about unless you point to the specific sources that you have seen. XOR'easter (talk) 17:54, 23 August 2022 (UTC)

I have reached such sources

• https://math24.net › ...

Differentiation and Integration of Fourier Series - Math24.net

• https://uwaterloo.ca › files › a...PDF

5.3.2 Integration of Fourier series AHEJJWILEMAMALIDGED (talk) 03:30, 24 August 2022 (UTC)

You have to include the whole URL. I’m not sure where you got the part you copy/pasted here, but nobody else can make use of it. I would recommend again that you ask for help on fa.wikipedia.org where Farsi speakers can help you figure out how to use your web browser and operating system if you run into technical difficulties. You are wasting your time and other people’s time struggling with this in English. –jacobolus (t) 18:00, 25 August 2022 (UTC)

@Jacobolus: AHEJJWILEMAMALIDGED was blocked two days ago. JBL (talk) 18:59, 25 August 2022 (UTC)

Creation a general page for two articles, area and volume

Hello, excuse me, I had two arguments for two theories and these two theories are very important, one for Fourier integral series and one for this topic of area and volume.

I believe that the concepts of volume and area in the article are not continuous and all of them are scattered and discrete, as well as the concepts of surface and volume such as era, enclosure, three-view drawing... are they even discrete or not. I recommend that we create a general article for volume and area and write their concepts such as period and enclosure, etc., so that there is a general and continuous concept for these two topics and the concepts of these two topics compared to the rest of the article. Through their discrete and reading through their reference or continuous article.Thanks AHEJJWILEMAMALIDGED (talk) 11:48, 11 August 2022 (UTC) Please reply to my text AHEJJWILEMAMALIDGED (talk) 12:47, 14 August 2022 (UTC)

What is wrong with the existing articles on area and volume? You are free to improve them, if you want to. JRSpriggs (talk) 20:04, 14 August 2022 (UTC)

Given the patchy grammar of AHEJJWILEMAMALIDGED's contributions here, I would suggest instead improving the coverage for the Wikipedia in a language they are more fluent in. —David Eppstein (talk) 21:36, 14 August 2022 (UTC)

There is no problem with two articles, area and volume, I say to add a general page for these two sciences and their concepts for more information. Like the analysis of mathematics, which defined its branches and wrote the main article of these concepts.that both the area and volume and their concepts should be in the form of separate articles and in the form of a general article and a complete and continuous reference. AHEJJWILEMAMALIDGED (talk) 05:21, 15 August 2022 (UTC) Mr. David Eppstein Hello, I am fluent in English AHEJJWILEMAMALIDGED (talk) 05:43, 15 August 2022 (UTC)

Sorry, but this is incoherent. --Kinu ^t/_c 12:20, 15 August 2022 (UTC)

I think a link to whatever it is that is wanted in Arabic was put here that would be best. Probably Google translate is being used and it isn't getting the meaning over properly. Too many words in mathematics mean smething quite differentin other contexts. NadVolum (talk) 12:47, 15 August 2022 (UTC)

Please list at least one English-language reliable source that treats the material in the way that you want. By doing so, you help us understand what you want, and you help us avoid original research. Mgnbar (talk) 13:27, 15 August 2022 (UTC)

Perhaps you a looking for something like Measure (mathematics). JRSpriggs (talk) 02:12, 16 August 2022 (UTC)

Hello, this article does not have any incoherent or unrelated topics. I can create a list of sources through English websites and books to write this page. I mean the area and volume article is not a measurement (mathematics) article, but related to It is.I am sure that this article will be widely viewed. We collect articles about volume and area and other concepts that are not made in this wiki from other sources and then create them. — Preceding unsigned comment added by AHEJJWILEMAMALIDGED (talk • contribs) 04:03, 16 August 2022 (UTC)

I think it would be best if you supplied something in a language you are proficient in rather than trying to do something in English. NadVolum (talk) 21:55, 16 August 2022 (UTC)

In addition to Persian, I am also fluent in English AHEJJWILEMAMALIDGED (talk) 04:15, 17 August 2022 (UTC)

You are not able to talk about mathematics in English with proficiency. It would be much easier for us to see what you are talking about in Persian and try and work out what you want from that. NadVolum (talk) 09:53, 17 August 2022 (UTC)

Yes, you are right, I am not very fluent, but I know to some extent. AHEJJWILEMAMALIDGED (talk) 14:21, 17 August 2022 (UTC)

Now let go of this issue. Our most important topic is about volume and area, not about mastering the English language, it is important that you present the main idea in any way. I told you my idea with this level of English. AHEJJWILEMAMALIDGED (talk) 14:31, 17 August 2022 (UTC)

I am grateful for the volume and area article that you are reviewing. However, it would be very good if the article that covers both area and volume and their concepts is created because:

• Through a general article and at the same time, we have a reference on the two topics of volume and area, and its topics are fully explained, and by reading it, people get to know their concepts in addition to area and volume. *We also have a separate article on volume and area and its concepts.AHEJJWILEMAMALIDGED (talk) 14:39, 17 August 2022 (UTC)

AHEJJWILEMAMALIDGED, I would recommend you you try working on the Farsi wikipedia instead; or if you insist on discussing here, perhaps you could find a fluent bilingual friend who can clearly relay your thoughts to an English-reading audience. English Wikipedia already has articles about area and volume, and nobody here understands what you are trying to say. –jacobolus (t) 17:54, 17 August 2022 (UTC)

Well, tell me from the beginning, my dear Now I will explain to you clearly and completely AHEJJWILEMAMALIDGED (talk) 04:41, 18 August 2022 (UTC)

It is true that the article on area and volume has already been made. But I say that we shall we come create an article that collects all the principles and concepts of area and volume, as well as other concepts such as:

• Rotation
• surrounded volume
• Drawing three views
• Extensive drawing of geometric *volumes
• section
• Cutting and...

It is also written in it.

This article is intended to be a complete and reference article on area and volume. AHEJJWILEMAMALIDGED (talk) 04:41, 18 August 2022 (UTC)

Why don’t you stop discussing possibilities here and go ahead and write that article in Farsi (or write a blog post or pamphlet or something in some other venue), and then people can look at it under machine translation or you can perhaps find someone fluent in both Farsi and English to translate it. From your brief description here, this sounds like a mishmash of several unrelated or loosely related topics that would be a nightmare to integrate as a Wikipedia article. Nobody here thinks this is an article that needs to be written, has any idea how to structure or write that article, or is going to write one for you based on a loose request. You are wasting your time. –jacobolus (t) 07:00, 18 August 2022 (UTC)

I understand completely What is You mean

1. People think I use machine translation
2. I need to find someone who is fluent in English and Persian to create this page I gave few ideas
3. I didn't fully explain how this article is
4. I am wasting time with mysterious and complicated words — Preceding unsigned comment added by AHEJJWILEMAMALIDGED (talk • contribs) 08:17, 18 August 2022 (UTC)

No, you did not understand what I meant; you are misunderstanding nearly every point. I didn’t say you are using machine translation or should find someone else to create your page. I said you should write something in Farsi, and then afterward someone could use machine translation to read it or you could find a translator. Your further efforts to “fully explain” are not clear and coherent enough English for people to understand what you are aiming for, which is why people are recommending you write your imagined article in Farsi instead. You are wasting time (yours and other people’s) not because of “mysterious words” but because nobody here is going to act based on comments of this type even if you repeat them a few more times. –jacobolus (t) 06:13, 19 August 2022 (UTC)

Oh, you mean that I should speak in Persian, right? AHEJJWILEMAMALIDGED (talk) 11:11, 19 August 2022 (UTC)

Not on this talk page. But perhaps you would find it easier to make yourself understood on https://fa.wikipedia.org/ rather than here on en. —David Eppstein (talk) 16:02, 19 August 2022 (UTC)

Yes, I also participate in Persian Wikipedia and I said my argument, but I also contribute in Persian and English. AHEJJWILEMAMALIDGED (talk) 04:09, 20 August 2022 (UTC)

It is an idea for this article.

1. The article must have a History.
2. The article should also have a topic such as definitions
3. The article should also explain other concepts (such as rotation, section, perimeter, etc.)
4. Then the article should show the area and volume of geometric volumes and explain the method of proving it.
5. The article should have a gallery to show the overall picture of geometric volumes.
6. The article should have a topic called application and importance
7. The article should be useful at the same time
8. The article should also have a bibliography for area and volume.

The area and volume article should have a history because people should know how area and volume were created and what are their other events and also get information about the scientists who worked in the field of area and volume. The article must also have definitions, because the definitions must explain about area and volume, about geometric volumes and non-geometric volumes, about prismatic, spherical, pyramidal volumes, etc.

The article should also have concepts that are about concepts such as rotation, circumference, section, etc., so that people can know more about them.

The article should also show the formulas of area and volume of geometric shapes and write their proof methods. This topic is an important topic in the article.

The article should have a gallery containing photos of geometric shapes such as prisms, pyramids, spheres, etc. so that people can get to know them more.

The article should have a topic called importance and application, that is, people should know what is the use of area and volume in life and what is its importance in mathematics and life.

The article should also be useful so that people use it more. Because one person may use it for conferences for example.

Nair article should have a bibliography topic so that people can read other topics through other references. AHEJJWILEMAMALIDGED (talk) 05:14, 19 August 2022 (UTC)

The articles area and volume are adequate as presented, and despite the OP's (repetitive) arguments, I see no logical reason for an article that redundantly shoehorns the two topics (along with other seemingly tangential information) into one. --Kinu ^t/_c 16:00, 19 August 2022 (UTC)

Why doesn't it make sense? I have already said what my purpose is and explained it in general — Preceding unsigned comment added by AHEJJWILEMAMALIDGED (talk • contribs) 03:57, 20 August 2022 (UTC)

I have to agree with the other users. area and volume already exist and seem to be quite reasonable articles, and I don't understand what AHEJJWILEMAMALIDGED is trying to accomplish. Meters (talk) 05:33, 21 August 2022 (UTC)

AHEJJWILEMAMALIDGED, at the moment, you literally have only eight contributions to the Article namespace, and basically all of the ones to mathematics-related articles have been reverted. Perhaps something is being lost in translation; despite what you say, I am concerned (as are other editors, based on their comments here) that you are not able to communicate effectively about mathematics in English. It's not that your ideas are bad, per se; it's just that they don't seem to be an improvement on what exists. Given that, I would recommend that you drop the stick and try to focus on improving the encyclopedia (perhaps not necessarily this one, but the Farsi one) in other ways that you are comfortable based on your knowledge and communication skills. --Kinu ^t/_c 05:50, 21 August 2022 (UTC)

I have to agree with others here and say that I cannot understand what AHEJJWILEMAMALIDGED is trying to communicate. My best guess is that they want a page which illustrates area and volume as being two particular manifestations of one single framework (such as Hausdorff measure?) Gumshoe2 (talk) 06:58, 21 August 2022 (UTC)

Hello,Gumshoe2 you almost understood my theory My theory is to create an article that includes the concepts of area and volume and other concepts in the context of the article. this article should also have a topic generalization and general structures. — Preceding unsigned comment added by AHEJJWILEMAMALIDGED (talk • contribs) 19:02, 21 August 2022 (UTC) AHEJJWILEMAMALIDGED (talk) 07:16, 21 August 2022 (UTC)

In the name of God

The article on area and volume was found in many sources, which has both theoretical and practical aspects and has the formula of area and volume and their proof method. About other concepts such as: Rotation, encirclement, three-view drawing, section, etc. have separate sources. Another source also said about its generalization. AHEJJWILEMAMALIDGED (talk) 08:26, 23 August 2022 (UTC)

Saying that you have seen a source, without any details, is not helpful. Please specify the URL or at least give the name so that we can find it with Google or in a library. JRSpriggs (talk) 17:47, 23 August 2022 (UTC)

We can collect area and volume content And the formulas of area and volume of geometric volumes and the method of proving them and the contents of period, section, conic section also created this article. I found all the materials of three-dimensional drawing, perimeter, section, etc.

• Area
• Volume
• rotation (geometry)
• Conic section

This content can be selected as a source. I have to refer to other sources. AHEJJWILEMAMALIDGED (talk) 03:53, 24 August 2022 (UTC)

We keep asking you for clarification and sources, yet you keep posting the same almost incoherent ramblings over and over again, both here and in other threads. I'm sorry, but this is basically disruptive editing at this point, and I am blocking as such per WP:IDHT. We've wasted enough time here. --Kinu ^t/_c 04:04, 24 August 2022 (UTC)

Blowing up in differential equations

Do we have an article to which the general concept of blowing-up in differential equations can be linked? For instance it is mentioned (without a link) in point five of Navier–Stokes existence and smoothness § Partial results, at Harmonic map § Singularities and weak solutions, at Differential inclusion § Theory, at Method of averaging § Example: Restricting the time interval, etc. It needs to be disambiguated at Blowing up (the unrelated concept in algebraic geometry) for which at least some of the incoming links are wrong (for instance one at Saruhashi Prize) but to do so we need an article to link in the hatnote and on blow up (disambiguation). —David Eppstein (talk) 20:45, 20 August 2022 (UTC)

Are you referring to what happens when the Taylor series no longer converges to the function? See Natural_logarithm#/media/File:LogTay.svg. JRSpriggs (talk) 22:15, 20 August 2022 (UTC)

I'm referring to a phenomenon where the solution to a differential equation blows up to an infinite (in some sense) value in a finite time. It is not about approximations to the solution; the solution itself blows up. Another relevant example is alluded to near the end of Painlevé conjecture. —David Eppstein (talk) 23:17, 20 August 2022 (UTC)

It may not be the best location, but would you like to add it to the Glossary of calculus ? --SilverMatsu (talk) 01:21, 21 August 2022 (UTC)

Comment-- to my knowledge "blowup" is in general (even beyond PDE) only a piece of colloquial/informal vocabulary which analysts use to say that something converges to infinity; in certain contexts it takes on a basically fixed meaning. For instance I would have no idea what someone really means if they just refer to "a PDE which blows up" or a "solution of a PDE which blows up"; I know exactly what someone must mean if they say "a Ricci flow on a closed manifold with finite-time blowup"; I could not be sure if they say "a Ricci flow on a noncompact manifold with finite-time blowup" although I could probably guess what they have in mind. A more general phrase like "blowup of Navier-Stokes" or "blowup of Ricci flow" has pretty much no 'a priori' or inherent mathematical meaning, although of course they might happen to be defined 'de facto' by general agreement in research community; this seems to be the case for Navier-Stokes. (Some people also talk about blowup at infinite time, e.g. [7].)

Give such context-dependence, it might be inappropriate for its own page. Maybe I agree with SilverMatsu that it is best to add to some glossary page, with an appropriately loose definition in the spirit of what you provided above to JRSpriggs. And then on each particular wikipage (e.g. Navier-Stokes, harmonic map, Ricci flow, etc) to specify what exactly it is typically taken to refer to in that context.

I should also point out the the very closely related phrases "blowup analysis" or "blowup limit" by which solutions which "blowup" are often studied. However these are also used equivalently in situations where it would be a little unusual to refer to "blowup" directly. For instance (starting with Sacks-Uhlenbeck) one may study singular points of weak harmonic maps by blowup analysis and blowup limits. This is exactly analogous to studying singular points of harmonic map heat flow, also by blowup analysis and blowup limit. However only the latter (I conjecture: only for psychological reason that former does not involve a variable commonly called "time") is commonly referred to as having a PDE solution which blows up. However in both cases one could specifically say "the gradient of the solution blows up along a certain sequence of points", and this would be well-understood (simply in the most general sense of convergence to infinity), and coincides with the commonly-understood notion of "solution blowup" in the heat flow case (when on a closed manifold). Gumshoe2 (talk) 06:47, 21 August 2022 (UTC)

This detailed and careful answer is very helpful; thanks! It is also why I didn't just go ahead and do something about this myself: getting the subtleties of this terminology right is beyond my expertise. But even if it is not well formalized as a general term, I think the lack of disambiguation of it at the algebraic geometry page and the disambiguation page is a problem, one that has led to wrong links. If there's something we could link to at those two pages, even a glossary page, that would help. —David Eppstein (talk) 07:00, 21 August 2022 (UTC)

Yes, completely agreed! Gumshoe2 (talk) 07:06, 21 August 2022 (UTC)

Calculus

I put some time into brushing the cobwebs out of the calculus article, since it looked both important and highly visible (in excess of 800K views per year). However, I'm increasingly busy and increasingly burned out. Would anyone like to try picking it up and getting it to GA status? XOR'easter (talk) 21:38, 14 August 2022 (UTC)

This article seems to me to have the wrong scope and organization for an article called "calculus". History is interesting and important but should be deferred, and the first few sections should try to introduce calculus in a more general way and describe how it is used in the world. In particular, there should probably be a more substantial discussion of differential equations as a basic tool of science and engineering. There should be some discussion of the calculus of variations. There should be more coverage of the calculus of finite differences and multivariable calculus ("multivariable", "differential form", "Stokes’s theorem" are not anywhere mentioned). The history section itself is also far too focused on (a) a priority dispute between Newton/Leibniz, and (b) disputes among mathematicians about axiomatic foundations, while almost entirely neglecting the history of the *use* of calculus (Euler and the Bernoullis are more important to the history of calculus than Weierstrass or Lebesgue). I don’t know if there are any good model articles out there with the right scope, but folks might want to start from the perspective of http://www.science.smith.edu/~callahan/intromine.html –jacobolus (t) 17:41, 16 August 2022 (UTC)

The history could be cut down drastically as there is a good separate article on the history. The history article has rather too short a lead, if it was given a proper summary in the lead that could be used in the calculus article. NadVolum (talk)

The existing sections of history could be cut down (as a somewhat unbalanced) but the history section overall could be expanded. I just think it should go in the middle or end of the article rather than the very beginning. The history of calculus article could be very dramatically expanded. –jacobolus (t) 01:08, 17 August 2022 (UTC)

What's the point of expanding the history section? It should just be a summary without any sections and point off to the proper article on the history of calculus. As it is at the moment a person is liable to do changes to the section on history in the calculus instead of the proper history article. It harms both articles to have a long section on the history in the wrong place. NadVolum (talk) 08:27, 18 August 2022 (UTC)

As a general rule, I’d prefer if Wikipedia authors tried to figure out the amount of material and the appropriate structure in any particular section likely to best serve the expected audience(s) for the article. So far as I know there’s no manual of style rule/guideline that a section summarizing a longer sub-article be of any particular length or structure. In the case of calculus the history is relevant and important and a summary that takes several paragraphs and maybe a few sub-sections seems fine. The article about history of calculus would ideally be greatly expanded; it currently mostly cuts off at ~1700. –jacobolus (t) 17:30, 21 August 2022 (UTC)

I'll have a go at updating the History of calulus article with the various different bits in the history section of calculus. It is not trivial, they have diverged quite bit and I'm not a fast worker. NadVolum (talk) 09:49, 18 August 2022 (UTC)

In my opinion, we should create a topic in this article called concepts so that the concept of integral, differential calculus, derivative, etc. will be presented in it.what is your opinion? AHEJJWILEMAMALIDGED (talk) 04:20, 17 August 2022 (UTC)

The naming of cats

There is a discussion on renaming Category:Set families at Wikipedia:Categories for discussion/Log/2022 August 17 § Category:Set families. More input from people with some mathematical expertise and less from Wikipedia category naming specialists might help. —David Eppstein (talk) 07:32, 23 August 2022 (UTC)

Reconstruct

I feel that this GA article, Derivative, has many problems which need to reconstruct as soon as possible. I'll make a new section on a talk page once I reread it. Do you mind if I ask? Dedhert.Jr (talk) 03:15, 24 August 2022 (UTC)

The article does look under-footnoted, by modern standards. My guess is that much of it dates back to the early years of Wikipedia. (Its GA reassessment was in 2007.) Fortunately, finding references for standard material is not so difficult; mostly it's a matter of picking which of the many books on the shelf are decently readable and not too hard to get hold of. The textbooks referenced in the Calculus article would be a good start. XOR'easter (talk) 16:18, 24 August 2022 (UTC)

XOR'easter I already gave my opinion and commentary on a talk page. And actually, there are a lot of things that I have to discuss it. You can reply here. Regards, Dedhert.Jr (talk) 15:38, 25 August 2022 (UTC)

Metric space and Metric (mathematics)

Recently I started trying to spruce up the metric space article. The more I think about it, the less the split between that and metric (mathematics) makes sense. For example, the section on examples of metric spaces, if it were better organized, could have a subsection on different metrics on $\mathbb {R} ^{2}$. But then those are examples of metrics on the "same" space!

The reasons for the split are summarized on a talk page, but I don't think they're great reasons. The articles duplicate each other to some degree and would have to duplicate each other even more to achieve really good exposition. The main topic that's covered in metric (mathematics) but not metric space is various weakenings of the metric axioms. Does it make sense to rename that article to something like generalized metric to focus it on this topic, and merge the rest into metric space? I would just go ahead and do it but I'm not sure about the naming, plus it's marked as a "high priority" article so someone obviously thought it was important.

Any comments or better naming suggestions? --platypeanArchcow (talk) 03:28, 24 August 2022 (UTC)

I am in complete agreement with you, and the given reasons for splitting are very weak. In my opinion the articles should just be merged, although I think it would also be ok to keep the second article purely for generalized metrics. Gumshoe2 (talk) 03:56, 24 August 2022 (UTC)

What Gumshoe2 said. I too find it is hard to justify having separate articles. However, it does seem to be a case that a metric can mean something more general than one in a metric space; just as a space can mean more than a topological space. For example, it seems a bit weird to have a discussion on a metric tensor in a metric space article. (I am not specialist) but a metric that varies from a point to a point should be discussed in some geometric fashions, the metric space article is not a good place for that. Maybe we need metric (geometry) or something, which discusses Riemannian metric, Kahler metric, etc. —- Taku (talk) 09:31, 24 August 2022 (UTC)

There is a difference between how the term metric is used in Geometry and in Differential Geometry. In the former a metric is a distance function on the space, while in the latter a metric is a family of inner products on the tangent spaces of the manifold, or the equivalent rank two tensor field. Both of these are distinct from a metric on a vector space, although the second is obviously closely related to it. Shmuel (Seymour J.) Metz Username:Chatul (talk) 15:49, 25 August 2022 (UTC)

Hartshorne here says “A distance function on a Hilbert plane is a function d that to each segment assigns an element of an ordered abelian group G such that ...” – is it worth mentioning such definitions? Everything on Wikipedia defines distances as real numbers under addition rather than elements of an arbitrary ordered abelian group. –jacobolus (t) 10:11, 24 August 2022 (UTC)

I would say yes, although I'm not sure where. IAC, wiki discusses, and should discuss,complex inner products. A case could be made for discussing generalizations to vectors spaces with normed scalar fields or to modules with normed scalar rings, but generlizing to arbitrary groups is a bit dicier. IMHO, we need to hear from a SME on such topics. Shmuel (Seymour J.) Metz Username:Chatul (talk) 16:03, 25 August 2022 (UTC)

Good points from everyone, thanks. I like the idea of just merging the articles. There are several separate "related topics" that need to be discussed or at least mentioned and linked in this article:

• The relationship between metric spaces and topological spaces, as well as in-between structures like uniform spaces
• Metric spaces with additional structure (e.g. Riemannian, sub-Riemannian, and Finsler manifolds, length spaces, normed vector spaces)
• Weakenings of the metric axioms, like quasi-, semi- etc. (I'm still tempted to silo detailed discussion of those into a separate article, maybe after merging with pseudometric space, because they don't feel important enough to me to discuss at length in the main article)

and optionally also

• Other modifications of the axioms (like metrics on multisets and the abelian group-valued metrics mentioned by jacobolus)

I think metric tensor is the right place for what Taku is proposing. We already have a metric disambiguation page which links to both concepts. --platypeanArchcow (talk) 15:44, 24 August 2022 (UTC)

I think manifold-specific discussion (metric tensors and so on) is pretty remote from what the metric space article should be. Sure, manifolds should be mentioned, but only briefly. I don't think there's any warrant to start talking about tensors in an article called "metric space". The topology discussed in the metric space article should be mostly point-set topology.

I guess maybe that means I'm against the merge. What might make sense to do is to move the more general content from metric (mathematics) into metric space, and the manifold-related content into metric tensor. Then the metric (mathematics) redirect could probably be deleted or disambig-ified. --Trovatore (talk) 16:07, 24 August 2022 (UTC)

To be clear, I agree with this. And metric (mathematics) currently has only a brief two-paragraph discussion of Riemannian manifolds, about as much as I intend to put in metric space. --platypeanArchcow (talk) 16:38, 24 August 2022 (UTC)

As analogy let me point out that a topological space defines a homology group, and that this is an important source of groups. But it would be misuse of language to conclude that a topological space is an example of a group, or that it is an example of something like "generalized group".

In exactly the same way, a (continuous) Riemannian manifold defines a metric space, i.e. a (continuous Riemannian) metric tensor defines a metric. Also in exactly the same way, it misuses language to say that a Riemannian manifold is an example of a metric space, or that a metric tensor is an example of a metric, or that a Riemannian manifold is an example of "generalized metric space". Just pointing this out in case there is any confusion.

Anyway, I agree with trovatore that a disambiguation page could be good, since differential geometers often use "metric" to implicitly refer to a Riemannian (or Finsler, etc) metric. But I think the material presently on this page about Riemannian metrics is all appropriate to a metric space page. However (per the above comments) I think it should be phrased and contextualized in a more proper way. Gumshoe2 (talk) 16:46, 24 August 2022 (UTC)

This brings up a good point: should metric (mathematics) redirect to metric space, or to metric (disambiguation) (which already exists)? --platypeanArchcow (talk) 16:48, 24 August 2022 (UTC)

Another article in the same general semantic space is distance. Obviously this should be a more informal article aimed at people with less math background, but covering overlapping ground. That said, I don't have a clear sense of what it should cover. It would be nice if someone could take the lead in making it coherent and useful. --platypeanArchcow (talk) 18:24, 24 August 2022 (UTC)

One potential difficulty with reorganization seems to be what to do with incoming links. There are a lot of links to "metric (mathematics)"; many refer to metric in a metric space but some other use metric in a (differential) geometric context. Redirecting metric (mathematics) to metric (disambiguation) means all of those links need to be modified, which actually is a right thing to do since "metric (mathematics)" is too generic and there shouldn’t be links to it. -- Taku (talk) 05:30, 25 August 2022 (UTC)

Well, I just did my part: Global LGBTQI+ Employee & Allies at Microsoft no longer links to that page. LOL. --platypeanArchcow (talk) 06:06, 25 August 2022 (UTC)

In all seriousness, the topic of that page is/was metrics in the metric space sense, not the differential geometry sense, so if there were incoming links referring to differential geometry sense they were already incorrect. --platypeanArchcow (talk) 06:10, 25 August 2022 (UTC)

Given what you all said above, I think the best solution is to merge the material at metric (mathematics) into metric space, and to allow metric tensor to continue to be the article covering the (quite different) notion of metric on a Riemannian manifold. Any link to metric (mathematics) should then link to either metric space or metric tensor, depending on what is intended. Ebony Jackson (talk) 21:40, 25 August 2022 (UTC)

OK -- the deed is done. I did a big rewrite of metric space and incorporated almost all the material from metric (mathematics). I also cleaned links to metric (mathematics) that needed to go somewhere else (though I may have missed some). Physicists were the big offenders, most of the wrong links needed to go to metric (general relativity). I redirected metric (mathematics) to metric space for now in order for link cleanup to happen. Eventually it can be redirected to metric (disambiguation) after the dust settles. As for metric space, it still needs some work: expanding the history section, adding more references and cleaning up the references that are there. But I need to get back to my actual job. Please let me know if you have any comments on the rewrite! --platypeanArchcow (talk) 01:10, 30 August 2022 (UTC)

Recent addition of fringe definition of Dirac delta as function to hyperreal numbers

I just came across Dirac delta function, where somebody has just added a reference to a paper proposing to define it as a function to hyperreal numbers in a very prominent fashion (it's the very second sentence on the page, as well as later on). This should probably be reverted, or the mention of it at least downgraded to a side remark somewhere in the history part, as it in my estimation is an unknown, fringe interpretation of an otherwise very widely used tool, and thus misleading to the general audience. As I am not too familiar with the English Wikipedia conventions for mathematics, I don't want to get involved in a dispute myself, but as the page is marked as a Good Article, I thought I would flag it here. --Clickingban (talk) 15:31, 27 August 2022 (UTC)

Thanks to pointing this. I have reverted this addition. Apparently, the editor who added this reference ignored that this was already discussed in section Dirac delta function § Infinitesimal delta functions. D.Lazard (talk) 15:58, 27 August 2022 (UTC)

It's not even altogether clear that this fringe definition is workable. Michael Hardy (talk) 19:00, 27 August 2022 (UTC)

Well it was published in a journal by a garbage publisher (MDPI) so there's no particular reason to suspect it would be correct, valid, or even sensible. JBL (talk) 20:33, 27 August 2022 (UTC)

Clarification in case anyone else goes through same confusion I just went through for a few minutes- the added intro text (presently removed from page) is to a MDPI publication but the original text linked to by D.Lazard is from a reputable journal, the Journal of Mathematical Physics. Gumshoe2 (talk) 23:17, 27 August 2022 (UTC)

This is also an odd citation though, somehow. It is a citation to a 1-page commentary on a paper by the same author in the same journal in 2006.

Maybe someone with a bit more clue in this area than me could check that this is actually a sensible citation, rather than citing the original paper (or another paper cited in the commentary note)? Felix QW (talk) 09:50, 28 August 2022 (UTC)

I don't know anything about nonstandard analysis but it looks to me like the wiki page correctly says exactly what the article contains. Of course, there could still be better references. Gumshoe2 (talk) 19:24, 28 August 2022 (UTC)

Just some remarks. (1) There is no such thing as a "fringe" definition in mathematics. Either it is a correct definition of an object (or space or whatever), or it is not a definition at all. There is nothing in between. Your personal dislike does not make a definition "fringe": your personal opinion is irrelevant. (2) The definition of the Dirac delta as an ordinary function is published in the journal Axiom which is indexed by the Science Citation Index of Clarivate. That makes it a recognized journal: there is no other criterion of demarcation between "good" and "bad" journals. Your personal dislike of the publisher doesn't make it a garbage journal: your personal opinion is irrelevant. (3) The definitions of the Dirac delta referred to in the section section Dirac delta function § Infinitesimal delta functions concern definitions as a function on the hyperreals. The definition in Axioms is a definition on the reals, which is not the same. (4) This is a wiki page about the Dirac delta, not your personal textbook on analysis. As such a new introduction should be included, even it makes other info obsolete. Such is the nature of scientific progress. For these reasons, I have restored the version with the new definition. — Preceding unsigned comment added by SwissGuy22 (talk • contribs)

"There is no other criterion of demarcation between "good" and "bad" journals." -- there are plenty. For example, Axioms is not indexed by Mathematical Reviews, which I and many other mathematicians would trust over SCI. Regardless, it is Wikipedia policy not to give undue weight to particular topics. Until this new definition is used in many other papers and (for a subject as basic and important as the Dirac delta function) textbooks, it should not be in the first paragraph of the article. --platypeanArchcow (talk) 00:24, 29 August 2022 (UTC)

You may have a fair point with MR but in the whole of science, being indexed in Clarivate's SCIE is widely regarded as a criterion for recognition or reliability of a journal. There is not a single professional scientist who would say that a journal indexed in Clarivate's SCIE is fraudulent or garbage. Then we might as well say that inclusion in the Ivy League is not a sufficient criterion for recognition of a university: why not start claiming that Harvard is a garbage university because anyone with money can get in and it sells courses that one can get for less than 1% of the money at a European university? You also may have a fair point with your comment about undue weight. But if we want to apply that policy consequently, we should start deleting references to isolated works of (often American?) scientists who use wikipedia as a PR forum. SwissGuy22 (talk) 12:02, 29 August 2022 (UTC)

If your assertions were valid then you would have a point, but (1), (2), and (4) are all certainly false. --JBL (talk) 00:42, 29 August 2022 (UTC)

If you say that (1) is false then you say that there *is* such a thing as a fringe definition in mathematics. That is utter nonsense and you know it: there is not a single scientific publication (article, textbook) where objective conditions have been established under which the predicate "fringe" applies to a mathematical definition. The predicate "fringe" is merely a pejorative used outside the framework of a scientific discussion to express one's personal dislike of something. SwissGuy22 (talk) 11:36, 29 August 2022 (UTC)

See WP:Fringe theories for a general definition of "fringe" that applies here. The aim of your edit is to replace the standard definition of Dirac delta (the one that appears in every textbook) by a different one that is not even mentioned in any textbook. This suffices definitively to qualify your definition as fringe. This has nothing to do with any personal dislike of something. D.Lazard (talk) 13:27, 29 August 2022 (UTC)

+1. JBL (talk) 17:05, 29 August 2022 (UTC)

The aim was not to replace the standard definition of the Dirac delta, but merely to mention that there is a new definition as an ordinary function on the reals. Good to know that Perelman's proof of Thurston's geometrization conjecture was just fringe mathematics before 2010 (when it appeared in a textbook). SwissGuy22 (talk) 08:58, 30 August 2022 (UTC)

People who solve millenium problems generally have a degree of self-respect that precludes publishing their work with MDPI and trying to self-promote on Wikipedia. --JBL (talk) 17:15, 30 August 2022 (UTC)

Then talk to your buddy D.Lazard who created his own wikipedia page Daniel Lazard SwissGuy22 (talk) 16:09, 31 August 2022 (UTC)

I don't know if it helps but there is a definition of Dirac delta in the framework of Sato's hyperfunction. This definition does not appear in the intro and I wouldn't say it is a *fringe* definition. The point is that the intro should only mention the standard definition and the body of the article can and should mention other definitions. In other words, reputations of journals, etc. aren't too relevant here; simply whether a definition is standard or not. -- Taku (talk) 09:48, 30 August 2022 (UTC)

Fair enough. I added the new definition to the body of the article. SwissGuy22 (talk) 11:51, 31 August 2022 (UTC)

The edit has immediately been reverted (twice) by D.Lazard; apparently D.Lazard and JBL think that the two of them having the same opinion means that there is consensus about this article; I can do other things with my time so goodbye! SwissGuy22 (talk) 16:15, 31 August 2022 (UTC)

Perfect, it sounds like everyone is in agreement about what would be best. JBL (talk) 17:28, 31 August 2022 (UTC)