Wikipedia talk:WikiProject Mathematics#Help with Simple harmonic motion

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Hello everyone,

In the past few days, I rewrote the entirety of the page about the pentagram map (it went from this to that). I'm continuing to do some small edits, for instance I'd like to make better illustrations. There is no survey article on the subject, and I'd like to submit it to the Wikijournal of Science.
I would appreciate any feedback on it, if some people have time.

Kind regards, Regliste (talk) 21:19, 2 December 2025 (UTC)[reply]

One big improvement for the images would be to make the text labels about 3x bigger. –jacobolus (t) 05:23, 3 December 2025 (UTC)[reply]

I thought the almost the same (about 3.14x times bigger), but jacobolus (t) wrote faster. :( MathKeduor7 (talk) 08:23, 3 December 2025 (UTC)[reply]

Yes, it's definitely needed, I was planning to do it. Thanks for the feedback. Regliste (talk) 09:33, 3 December 2025 (UTC)[reply]

I fixed one broken ref template (wrong year). ~2025-31850-11 (talk) 11:23, 3 December 2025 (UTC)[reply]

Thanks. I also updated the images to be more readable. Regliste (talk) 15:09, 3 December 2025 (UTC)[reply]

Hi all, was hoping someone who knows a bit more about statistics may be able to help with a COI request at Talk:Little's law. Thanks, Encoded  Talk 💬 13:13, 4 December 2025 (UTC)[reply]

I took care of it. Malparti (talk) 14:31, 4 December 2025 (UTC)[reply]

For WikiProjects that participate in rating articles, the banners for talk pages usually say something like:

• "This article has been rated as Low-importance on the importance scale."

There is a proposal to change the default wording on the banners to say "priority" instead of "importance". This could affect the template for your group. Please join the discussion at Wikipedia talk:WikiProject Council#Proposal to update wording on WikiProject banners. Stefen 𝕋ower ^{Huddle • Handiwerk} 19:45, 6 December 2025 (UTC) (on behalf of the WikiProject Council)[reply]

Our banner has for a long time called this priority not importance. —David Eppstein (talk) 20:16, 6 December 2025 (UTC)[reply]

There is a requested move discussion at Talk:Jean le Rond d'Alembert#Requested move 29 November 2025 that may be of interest to members of this WikiProject. TarnishedPath^talk 02:19, 7 December 2025 (UTC)[reply]

Can someone with sufficient understanding of the subject please take a look at this question: Talk:Absolute infinite#Tav letter? It could be a mystification, especially considering that no supporting source has been indicated, and the information on the actual symbol of "absolute infinite" (omega letter - Ω) was removed by the same editor. Much appreciated. -- Prokurator11 (talk) 03:30, 7 December 2025 (UTC)[reply]

Tav (ת‎) is the last letter of the Hebrew alphabet. Some people choose to use it to stand for the class of all ordinals (Ord or On). I am not surprised that some people view it as God-like since treating it like an ordinary ordinal leads to contradictions. On the other hand, capital Omega (Ω) does not stand for that class, rather it stands for ω₁ which is the least uncountable initial ordinal or the least regular ordinal larger than ω. JRSpriggs (talk) 16:24, 7 December 2025 (UTC)[reply]

I've removed the tav stuff. If re-added it should be sourced and it should be explained who uses it this way. I've never seen it. --Trovatore (talk) 22:28, 7 December 2025 (UTC)[reply]

Please add reliable sources. Bearian (talk) 03:42, 7 December 2025 (UTC)[reply]

@Bearian. Umm... why can't you be the provider instead? Dedhert.Jr (talk) 05:08, 8 December 2025 (UTC)[reply]

@Dedhert.Jr, I think Bearian is a lawyer whose name isn't some variant of Petrus (unlike this this guy and this guy); so most likely he doesn't know enough about the topic to look for sources efficiently. Malparti (talk) 08:01, 8 December 2025 (UTC)[reply]

@Malparti. Ohh... I'm sorry then. Dedhert.Jr (talk) 08:14, 8 December 2025 (UTC)[reply]

Yes @Malparti. I have been a math teacher, but the farthest I taught was 7th grade math (in the United States that means ratios, fractions, etc.), and the farthest I've studied was 3 college courses in statistics, and very basic calculus. Monomial basis is beyond the scope of my zone of proximal development. Bearian (talk) 13:11, 8 December 2025 (UTC)[reply]

@Bearian. From what I observed, the monomial basis tends to a higher level of algebra. Relatedly, the polynomial basis is also redirected to the same article, which is the worst. Dedhert.Jr (talk) 08:20, 9 December 2025 (UTC)[reply]

I started adding some pointers to a book in the general area that people I know seem to like. My guess is that works which introduce Gröbner bases will also talk about these. Stepwise Continuous Dysfunction (talk) 07:39, 10 December 2025 (UTC)[reply]

The basic problem with this article is dramatic incompleteness, not sourcing per se.

The most important single thing to say about the monomial basis in my opinion (at least for its relevance to analysis), currently unmentioned, is that the coefficients of a polynomial (or infinite series) in monomial basis represent the local behavior near the origin in the complex plane, and are proportional to the values of the various derivatives of the function there (cf. Taylor series). When the series is the Taylor series of some non-polynomial function, it will converge within an origin-centered disk in the complex plane, whose radius is as large as possible such that the function is analytic inside the disk.

The article should explicitly contrast the monomial basis with various other polynomial bases, and explain the differences in high level concepts as well as concrete technical details. For example it is important to mention that polynomials in monomial basis should generally not be used for numerical evaluation away from the origin, and other polynomial bases are much better for representing a polynomial over a specific real interval or arbitrary region in the complex plane. –jacobolus (t) 09:55, 10 December 2025 (UTC)[reply]

@Jacobolus I thought the main interest of a monomial basis is for algebra, not for analysis. In particular, see the articles Gröbner basis and Monomial order, which is used in algorithms to compute Grobner bases. What you mention about Taylor series and convergence in the complex place is not directly relevant to this. Monomial bases are used over any kind of field or ring, and are used in commutative algebra and computational algebraic geometry. PatrickR2 (talk) 04:36, 11 December 2025 (UTC)[reply]

My impression is that polynomials (including in monomial basis) are used ubiquitously and are of interest throughout mathematics. –jacobolus (t) 07:36, 11 December 2025 (UTC)[reply]

I met these concepts through algebra, rather than analysis, but if there are books about analysis that talk about them, go ahead and expand the page! :-) Stepwise Continuous Dysfunction (talk) 21:39, 11 December 2025 (UTC)[reply]

I don't trust my own judgment right now, but shouldn't Orbison illusion have a math category? (because to know it's not a square one needs mathematical reasoning...)? MathKeduor7 (talk) 17:01, 8 December 2025 (UTC)[reply]

There is nothing really mathematical about that article. You could probably stretch any article to have a math category. For example, to understand that Spamalot grossed more than $168 million dollars you need number sense. A topic requiring some math knowledge is not sufficient to be in the math category, else almost every article would be that. EulerianTrail (talk) 17:13, 8 December 2025 (UTC)[reply]

Hi, EulerianTrail... What about mentioning it at the page square?? I think it's relevant. MathKeduor7 (talk) 05:03, 9 December 2025 (UTC)[reply]

Orbison illusion is more of a psychology topic about people's perception of shapes that are overlaid with radial lines and concentric circles. So, adding it to the square page seems out of place. I could see a mention at Line (geometry) or Curve but it does not seem needed nor notable as a math topic. EulerianTrail (talk) 05:53, 9 December 2025 (UTC)[reply]

@MathKeduor7. Well, if there is something that resembles a square, you can added to see-also section, or finding a source and put it to the body, if you want to. Dedhert.Jr (talk) 08:24, 9 December 2025 (UTC)[reply]

Thank you two! MathKeduor7 (talk) 09:39, 9 December 2025 (UTC)[reply]

Should regular icosahedron be merged to icosahedron per discussion? My opinion is that both articles have different purposes of informing the audience: icosahedron talks about the twenty-sided polyhedron, while the regular icosahedron focuses more on its characteristics and applications. At first, I thought that merging it would give the problem of WP:TOOBIG and it already meets notability under WP:GNG, but soon realized they have common topics in terms of relations to other polyhedra (i.e., stellation, Jessen icosahedron, pyritohedral version).

I have no further comments about this, so I'll hear your opinions. And this should be discussed in WP:3TOPE, but still due to lack of activity. Dedhert.Jr (talk) 01:10, 10 December 2025 (UTC)[reply]

On the talk page of Regular Icosahedron, @jacobouls suggested an idea that I like, which would to keep the icosahedron pages as is but create seperate pages for Regular Pentagon and Regular hexagon to maintain consistency. VidanaliK (talk) 01:50, 10 December 2025 (UTC)[reply]

The treatment of modern PDEs across WPM articles seems surprisingly lackluster to me. To my eye, any mathematician studying PDEs in <current year> works extensively with weak/variational formulations and the estimates they yield. I believe that many articles on specific PDEs could be improved by adding a treatment of their weak formulation, and a few results about their well-posedness.

The only article I am aware of that includes such a treatment is the article on the Navier-Stokes equations. Even so, I think that the article would benefit from trimming down the details of the derivation which could instead be found in any source on mathematical fluid dyanamics, in favor of some results concercing the weak formulation. For instance, it is frankly crazy to me that the article on the Navier-Stokes equations contains no mention of the energy inequality $${\displaystyle \Vert u(t)\Vert ^{2}+2\nu \int _{0}^{t}\Vert \nabla u\Vert ^{2}\,dt\leq \Vert u_{0}\Vert ^{2},}$$ which is a classic result dating back to Jean Leray.

I do not mean to rant but these sorts of estimates are pervasive in PDEs literature. Therefore I propose to add details about the weak formulations of PDEs to various articles with the following goals:

• Expand the articles on Weak formulations and Weak solutions to contain enough information to comprehend basic results concerning well-posedness of some of the most common PDES. Whether this is done via the theory of distributions or weak derivatives could be up for debate, although I have my own opinion.

• Trim existing sections on weak forms which rely heavily on derivations in favor of results such as:

• Collect common facts about well posedness (i.e. existence and uniqueness of weak solutions).

• Collect common facts about estimates on solutions and regularity.

• Perhaps discuss mild solutions in articles concerning time-dependent PDEs.

Emgram (talk) 06:18, 11 December 2025 (UTC)[reply]

No one will complain if you add content to Wikipedia articles that is in accordance with WP:V, WP:NPOV, WP:TECHNICAL, WP:LINKSPAM, etc. It is less clear to me how people will feel if you start removing cited, on-topic material. ~2025-31168-81 (talk) 16:38, 11 December 2025 (UTC)[reply]

Thank you for the feedback. I am new to editing on Wikipedia so I will keep this in mind! Emgram (talk) 00:47, 12 December 2025 (UTC)[reply]

Indeed you are; welcome! ~2025-31850-11 (talk) 11:02, 12 December 2025 (UTC)[reply]

I am not quite good enough at topology to say for definite but I think cantor fan redirecting to Knaster–Kuratowski fan might be a mistake. I am fairly sure that the cantor fan is a cone over the cantor set and the knaster-kuatowski one is a proper subset of it. Flapjack06 (talk) 14:59, 11 December 2025 (UTC)[reply]

Title X may redirect to title Y not because X and Y are synonymous but instead because the best current coverage of topic X is at the article titled Y, or because topic X is insufficiently notably to be the topic of its own article but merits mention in the article on Y. (I do not have an opinion about whether that is the case in this instance.) ~2025-31168-81 (talk) 16:42, 11 December 2025 (UTC)[reply]

As the person who rewrote most of article Y I can say that topic X is not mentioned in it and I don’t think it is the best place for it to be mentioned. I am trying to improve the area around Knaster-Kuratowski fan but I am new here, not that experienced in topology, and the articles are mostly spaces constructed with the express purpose of having weird and unintuitive properties so I wanted a second eye to check over it before I was quite that bold and thought this might be the best place for that. I should probably have said most of this in the original comment. Flapjack06 (talk) 16:55, 11 December 2025 (UTC)[reply]

@Flapjack06 The redirect from Cantor fan to Knaster–Kuratowski fan was created by user "Hyacinth" in July 2016. Most of her contributions were about music and not mathematics, so one can assume she did not fully grasp the difference. Furthermore, the user is now deceased, so no way to ask for feedback. On the other hand, Dendroid (topology) is only page that makes use of that redirect, and explicitly mentions it as a cone over the Cantor set, which the Knaster–Kuratowski fan is not. So the right thing to do would be: (1) edit Dendroid (topology) to not make use of that link, and then (2) start the process to delete that redirect. (I forgot how to do it myself, but hopefully someone here can comment on the procedure). PatrickR2 (talk) 03:17, 12 December 2025 (UTC)[reply]

The Knaster–Kuratowski fan article does discuss the cone over the Cantor set, though, so it might be the best redirect target unless/until we have a separate Cantor fan article. —David Eppstein (talk) 06:09, 12 December 2025 (UTC)[reply]

Sorry, what is meant by "the cone over the Cantor set"? The image in the article looks sort of cone-like, I guess, but the word "cone" does not appear, and I'm not familiar with the notion of "cone over" in general. --Trovatore (talk) 06:23, 12 December 2025 (UTC)[reply]

A cone over a space X is usually defined as the product ${\displaystyle X\times [0,1]}$ with the top portion ${\displaystyle X\times \{1\}}$ identified to a point. So it's like a cone with full rays from each point of the base to the vertex. That is really different from the K-K fan, where all the "rays" are punctured in various ways, and keeping this redirect just confuses things more than anything else. PatrickR2 (talk) 06:33, 12 December 2025 (UTC)[reply]

Nice. Now I have a word to explain why the Big Bang doesn't prove that the universe is spatially finite. --Trovatore (talk) 07:26, 12 December 2025 (UTC)[reply]

It is different from the K-K fan, but it is identical to the construction in the first paragraph of Knaster–Kuratowski fan § Construction. It is pretty common for redirects to point to parts of other articles that discuss those topics. For it to be a redirect, though, it should say at that point of the article that what it is talking about there is called the Cantor fan. Maybe it should say that anyway. —David Eppstein (talk) 07:17, 12 December 2025 (UTC)[reply]

FYI, on the Dendroid (topology) page I have now removed the link from "Cantor fan" to the K-K fan, as it was incorrect. (Cantor fan is still mentioned, but without a link.) So as of now there are no more pages that make use of the Cantor fan redirect and this redirect can safely be removed. @Flapjack06, you can now follow the process for deleting it. PatrickR2 (talk) 07:05, 12 December 2025 (UTC)[reply]

Tosiaki! has been greatly expanding the ordinal number article, which is fine in itself and some of the new material is good, I think (I say I think because I haven't looked into detail into that). However he/she/they has added a lot of detail as to the proofs of elementary facts. In my view this goes against WP:NOTTEXTBOOK (and in fact is worse than that, because in an actual textbook these arguments would probably be in the exercises). I think this is entirely inappropriate for an encyclopedia article. Please join in the discussion, whichever view you have. --Trovatore (talk) 06:11, 12 December 2025 (UTC)[reply]

I completely agree with @Trovatore here and have posted a comment on that Talk page. Please follow up the discussion over there. PatrickR2 (talk) 06:49, 12 December 2025 (UTC)[reply]

It looks like this might be resolved already but just in case the talk section in question is Talk:Ordinal number#Excessive detail in von Neumann section. ~2025-31850-11 (talk) 11:06, 12 December 2025 (UTC)[reply]

Note: The same user @Tosiaki! has also decided to modify the lead of the article Stone–Čech compactification. This has considerably bloated the lead and diluted some of the ideas, and all without any references. Could this be construed as WP:OR or WP:SYNTH? I agree it has added "motivation", but perhaps at the cost of replacing the previous concise summary with a dumbed down bunch of fuzzy ideas (good for laypeople maybe, but why would laypeople need to care about Stone-Cech compactification anyway). This change seems misguided to me. But please comment below, if you understand the situation differently. PatrickR2 (talk) 20:59, 12 December 2025 (UTC)[reply]

I really don't see how it's going to help laypersons. Table stakes for reading the article is knowing what a compact Hausdorff space is, and that would take at least a few hours to explain to anyone who hasn't seen the basic notions of general topology. And what it means for a map to "factor through" something is even more abstract. That said, I don't necessarily hate it for the "one level down" intended audience. --Trovatore (talk) 06:27, 13 December 2025 (UTC)[reply]

The previous first paragraph (added by Tito Omburo) was really good, it’s a shame it’s been replaced with something more technical. The article lead should have a paragraph understandable by an undergraduate math major. ~2025-31850-11 (talk) 12:30, 13 December 2025 (UTC)[reply]

The motivation section is also good, except that its first paragraph should be reintegrated into the lead. PatrickR2’s comments seem wildly misguided: the right audience is not laypeople, it is “people who have just completed the prerequisite class to the one where this idea might normally be introduced”. The material added by TO and T! seems like a major improvement in accessibility, in accordance with WP:ONELEVELDOWN. ~2025-31850-11 (talk) 12:42, 13 December 2025 (UTC)[reply]

I pulled Tito Omburo's first paragraph out of the revision history and re-integrated it into the new lead. I also moved the line about the history into the first paragraph, since that's a fairly digestible detail. Stepwise Continuous Dysfunction (talk) 19:58, 13 December 2025 (UTC)[reply]

@Stepwise Continuous Dysfunction Thank you for this. Nice improvement. PatrickR2 (talk) 21:12, 13 December 2025 (UTC)[reply]

I agree! ~2025-31850-11 (talk) 11:42, 14 December 2025 (UTC)[reply]

Thanks. Stepwise Continuous Dysfunction (talk) 07:49, 15 December 2025 (UTC)[reply]

@~2025-31850-11 Do you mid logging in before commenting? Using an anonymous account is not helpful to know who you are. PatrickR2 (talk) 21:05, 13 December 2025 (UTC)[reply]

What I mean is that you write very cogently, so most probably you have contributed to many discussions in WPM in the past. So it would be good to associate the anonymous account with a person we know well in this forum. PatrickR2 (talk) 21:19, 13 December 2025 (UTC)[reply]

Yes I have edited for a long time under IPs before temporary accounts were created, most recently as 173.79.19.248. ~2025-31850-11 (talk) 11:40, 14 December 2025 (UTC)[reply]

Hello everyone,
I revamped the page about the pentagram map, and I thought that it could use a reassessment? I'm unsure of the procedure to follow. I wrote a request on WP:ASSESS/REQ, but maybe the WP:WPM has specifities I'm unaware of.
Thanks to anyone who will take a look, Regliste (talk) 11:28, 14 December 2025 (UTC)[reply]

I could only give C for the assessment. The article looks unsourced in some spots. Dedhert.Jr (talk) 07:07, 15 December 2025 (UTC)[reply]

The overall footnote density looks OK to me. What stands out as unsourced? Stepwise Continuous Dysfunction (talk) 07:48, 15 December 2025 (UTC)[reply]

@Stepwise Continuous Dysfunction. I meant there are some unsourced paragraphs that can be found; take some examples of two unsourced paragraphs in the section of "Arnold–Liouville integrability", the introduction paragraph of "Periodic orbits on the moduli space", the unsourced paragraphs in "Twisted polygons", etc. Dedhert.Jr (talk) 08:34, 15 December 2025 (UTC)[reply]

And one more thing. Is the article supposed to be technical? Maybe you can try to explain the background per WP:MTAU. Missing source from the citation of Ovsienko, Schwartz & Tabachnikov 2011. In the meantime, I can only give some citations from the given inlines. Feel free to revert if you have any disagreement. Dedhert.Jr (talk) 08:35, 15 December 2025 (UTC)[reply]

Thanks for the reread.

For the sourcing, I didn't wanted to cite again and again the same paper many times in a same paragraph. Also, other papers are referring to the same concepts (they are classical in the field), but I didn't want to make it too heavy. I can do it if needed, because I assure you this is no original research.

For the introductory section of "Periodic orbits on the moduli space", it is an attempt to clarify the following, which is sourced.

One last question: isn't C a bit harsh ? This is, according to the specialists I sent the article for a review, the most up to date page in term of content about the pentagram map. Though I can hear that the style could be enhanced, in term of clarity for instance (but since it's very specialized, I don't find it easy to summarize for the layman). Regliste (talk) 16:13, 15 December 2025 (UTC)[reply]

C is not as bad as it sounds. You have to consider that B is roughly GA. I don't think we give A's anymore (do we?) but those were supposed to be roughly FA. It's not a very intuitive scale and it can come across as a little insulting, but it's what we've got. --Trovatore (talk) 19:32, 15 December 2025 (UTC)[reply]

Yes, "C" sounds low (particularly if you have the American grading system drilled into your brain), but it's not that harsh in the Wikipedian system, all things told. I'm still giving it a read-through, but I think that if David Eppstein's points below are addressed, it'd be well on its way to GA. Stepwise Continuous Dysfunction (talk) 23:57, 15 December 2025 (UTC)[reply]

A few comments:

• The article repeatedly refers to "shortest diagonals" without explaining what this means. It appears to actually mean "diagonals between vertices two steps apart" but I would expect it to mean "diagonals of minimal Euclidean length", a totally different thing. This ambiguity should be fixed.
• All the examples are of convex polygons (or locally-convex "twisted polygons"), but the article does not ever state that this system is restricted to convex polygons. For polygons that are not convex, the diagonals might not cross. How is the system defined in that case? Which of the claimed results about these systems require the polygon to be convex? Or are these systems only defined for convex polygons? If so, the article should say so. Alternatively, if this is to be in the projective plane as it says, then the link to diagonal is not right (that is for Euclidean polygons and talks about line segments but for the projective plane you presumably want the entire line determined by two vertices), and maybe it should make a distinction between contractible and uncontractible polygons?
• Relatedly, the assumption of general position in the "Definition of the map" section is stated very vaguely. But for convex polygons it is completely unnecessary: the vertices of convex polygons are automatically in general position.
• I agree with prior comments about sourcing. As a general rule, to meet B-class (and as an explicit rule for GA-class), every claim in the article should be followed by a footnote supporting that claim, in the same paragraph. This means that most paragraphs should end with a footnote (exceptions include lead paragraphs that summarize later sourced content, and simple calculations).

—David Eppstein (talk) 19:50, 15 December 2025 (UTC)[reply]

Thank you very much for your detailed comments. I'll try to address these points when I'll have time. Regliste (talk) 10:59, 16 December 2025 (UTC)[reply]

Specifically on the last point: if a single footnote covers multiple consecutive sentences, you can put it at the end of the last sentence in the block; it sounds (based on your comments) like you’ve been putting it earlier, which creates an illusion of unsourced content.

By the way, I wonder if any of these papers (that I happen to know about by coincidence; not an expert) suggests content that could be included. https://link.springer.com/article/10.1007/s10801-012-0417-6

https://www.sciencedirect.com/science/article/pii/S0393044014001703

https://academic.oup.com/plms/article-abstract/112/4/753/1752706

(No matter if not; once upon a time I went to some talks by their author.) ~2025-31850-11 (talk) 11:47, 16 December 2025 (UTC)[reply]

The demand for a footnote at the end of each paragraph is an unusual Wikipedia-ism not found in any other kind of written document. It's not important to typical readers (who can usually figure out which of the cited sources applies if they care), but does save some effort for editors trying to carefully track each claim to a specific source. Some folks on Wikipedia, especially the ones deciding whether articles deserve badges, hold ubiquitous footnotes to be the site's top priority, so it's easiest just tack a footnote onto each paragraph, which they will scan for and usually be satisfied if they see. –jacobolus (t) 12:28, 16 December 2025 (UTC)[reply]

I'd like a third opinion for a page move proposed by Trovatore in 2005 sending Large cardinal (talk page here) to "large cardinal property", since this undoes a previous user's work. The Boolean^_Talk 07:03, 15 December 2025 (UTC)[reply]

It's a very old and stale discussion. I think it can be considered to be closed without action. Or are you trying to revive the move request? —David Eppstein (talk) 00:13, 16 December 2025 (UTC)[reply]

I never got around to proposing an official requested move (not even sure there was such a thing in 2005). I do still think the current title is a bit problematic, because it suggests that there's a well-specified class of objects called "large cardinal", but I'd have to re-think what I think is the best title. Anyway I think "The Boolean" wants to know if anyone else thinks that's a good idea (I think R.e.b. has left the project and is not going to give an opinion). --Trovatore (talk) 00:38, 16 December 2025 (UTC)[reply]

OK, I looked back through the history and refreshed my memory. I moved it to large cardinal property on 6 November 2005. R.e.b. moved it back three years later, on 26 November 2009, with the edit summary "[m]ost common name".

I agree that it's a more common name, but in my view that's less important than whether it names what the article is actually about, and I would argue that it does not. So I think it should be moved back to large cardinal property. If R.e.b. is still logging in and sees this notification, consider this an invitation to comment. --Trovatore (talk) 06:56, 16 December 2025 (UTC)[reply]

My impression (not being at all expert on this) is that it's more intuitive to think of the subject as being about "large cardinals" (as individual cardinal numbers that behave in unusual ways) but that the formalization of the subject leads to more of a focus on the properties that these cardinals might have rather than on their individual values. So changing the name to be about the formalization rather than about the intuition would be a step in the wrong direction with respect to WP:TECHNICAL. Similarly, we have an article prime number with a name focused on the individual numbers, not primality focusing on the property that these numbers have. Am I mistaken?

Sadly, I suspect R.e.b. is not coming back. —David Eppstein (talk) 07:12, 16 December 2025 (UTC)[reply]

Well, the comparison with prime number actually exemplifies my point pretty well. There's a single well-specified notion of which numbers are prime. There's no single well-specified notion of which cardinals are large.

What the article is about is not the cardinals, but about the (many many many) different notions of how cardinals can be large. --Trovatore (talk) 07:15, 16 December 2025 (UTC)[reply]

This is more of a comment. But I want to mention we do have the article called closed graph property, because, well, a closed graph isn't a mathematical object. So, an article title "X property" isn't necessarily a strange thing. On the other hand, we do have articles like generalized functions even though there is no well-defined class of generalized functions. So, to me, the question seems to be of Platonic one in that: do we have the notion(s) of large cardinals in Platonic sense if not in working math sense? I don't know enough set theory to answer this. -- Taku (talk) 08:16, 16 December 2025 (UTC)[reply]

I'm not completely sure I follow your question. Do you mean is there a sort of general I-know-it-when-I-see-it understanding of what large cardinals are in general? I would say yes, there is. It seems to be resistant to abstract formalization. Woodin came up with an abstract general definition but it's not clear how seriously he meant it; it was for a limited purpose.

I think the best version I've heard is John R. Steel's, where he says that they are "natural markers of consistency strength". This does leave some open questions ("natural" in what sense? Why doesn't it include determinacy hypotheses?) but it's a great starting point. If we can find it published we should include it in the article. --Trovatore (talk) 19:27, 16 December 2025 (UTC)[reply]

Quoting myself from Talk:Large cardinal, "merely being a very large cardinal does not guarantee that the cardinal will have a large cardinal property. For example, if Γ is an I0-cardinal, then its successor cardinal Γ⁺ will not even be weakly inaccessible despite being enormously large". So what we are really talking about is being a very strong kind of limit, whatever that means. JRSpriggs (talk) 14:37, 16 December 2025 (UTC)[reply]

I find that argument more persuasive than the argument that the article is really about the properties and not about the cardinals that have those properties. —David Eppstein (talk) 18:44, 16 December 2025 (UTC)[reply]

JR's point is another way to see the same thing, I think. It comes back to the fact that there is no notion where we say this cardinal is large and that one isn't. Rather, this cardinal has a particular large cardinal property and that one doesn't, or maybe that one has a weaker large cardinal property.

The article is largely about the hierarchy of these properties. I really don't see how it's about the cardinals themselves. Articles on individual types of large cardinal, say inaccessible cardinal or measurable cardinal, can be thought of being about the cardinals themselves. But the article under discussion really isn't. It's about the hierarchy of properties.

(An alternative would be to say it's about a hierarchy of axioms — that would have the advantage of more explicitly including statements like "there are a proper class of inaccessible cardinals". The disadvantage, to me, is that it sounds formalistic, as though we're just discussing formal strings rather than infinite objects.) --Trovatore (talk) 19:20, 16 December 2025 (UTC)[reply]

The monus operator is denoted by a dot-minus character. We have \dotplus "${\displaystyle \dotplus }$", but sadly not \dotminus (or \dottimes). It's also used in the article on prime formulas. The alternative of making your own in LaTeX ("${\displaystyle \mathbin {\dot {-}} }$") has the dot positioned much too high. Where should I request help for this? — The Anome (talk) 22:48, 16 December 2025 (UTC)[reply]

Unfortunately our LaTeX implementation here doesn't support most of the ways of overlapping symbols or precisely adjusting space (e.g. squash, rlap, hskip, ...), but you could try to make a workaround by using \dot with an empty argument and adding the appropriate number of negative spaces before placing the minus sign, e.g. ${\displaystyle a\mathbin {\,{\dot {}}\!\!\!\!-} b}$. Does that get the dot at the right height? Edit: what specifically is this supposed to look like? How big a dot do we want, and how high? Are you looking for something like a division sign ⁠${\displaystyle a\div b}$⁠ without the bottom dot? –jacobolus (t) 23:02, 16 December 2025 (UTC)[reply]

For actual LaTeX there are suggestions at [1] and [2] but I'm not sure any of them work for our ersatz LaTeX. You could use U+2238 ∸ DOT MINUS outside of math mode. —David Eppstein (talk) 23:07, 16 December 2025 (UTC)[reply]

The pages Aboodh transform and Sumudu transform are pages created by a (now) user blocked for WP:NOTHERE behavior including the creation of many bad pages. A large number if these have now either been edited by others, or CSD/PROD/AfD. These two could do with expert checking. Ta. Ldm1954 (talk) 13:12, 17 December 2025 (UTC)[reply]

I do not find these topics interesting; my general impression is that they come from an area of mathematics with inflated citation counts for small contributions. However, they are discussed by large numbers of works in Google Scholar and even in MathSciNet. Because of that, I don't know of a principled way of gatekeeping that could keep them out. —David Eppstein (talk) 19:05, 17 December 2025 (UTC)[reply]

Oh wow. And International Journal of Mathematical Education in Science and Technology even made it to Q1. I guess there really is nothing we can do.

Also, gotta love it when someone names their method after themselves — really adds that Tai's model vibe (and, by the way: yes, this is the "official" PDF from the publisher's website). Malparti (talk) 20:43, 17 December 2025 (UTC)[reply]

I'd say that stubs with bad sources (deadlinks, MDPI, etc.) could be boldly redirected, say to Integral transform as redirects-with-possibilities, with the understanding that if they are actually important, a user in good standing can write about them with better sources. Keeping bits of cruft like this around goes against the spirit of building a worthwhile encyclopedia even if they're not technically OR. Stepwise Continuous Dysfunction (talk) 21:38, 17 December 2025 (UTC)[reply]

But that's the problem: look at the sources of the article on the Sumudu transform:

1. is published in a (now) Q1 journal and cited 865 times (more than 1000 if you count citations to the same article but with a different year);
2. is in the same journal and has 193 citations;
3. is published by Springer (and cited 11 times);
4. is published another Q1 journal and has 176 citations.

so by standard metrics, the article on the Sumudu transform does not have bad sources...

That said, to reply to @Ldm1954's original question: the current version of those stubs can probably be deleted on the grounds of being "too poorly written to be useful". Malparti (talk) 22:00, 17 December 2025 (UTC)[reply]

Potentially, one could write a sentence along the lines of, "A variant of the Laplace transform, defined by [formula], is sometimes called the Sumudu transform and has been applied to [problem X] and [problem Y]." Stick that in another article and make Sumudu transform into a redirect. Stepwise Continuous Dysfunction (talk) 22:07, 17 December 2025 (UTC)[reply]

I concur. Redirected Aboodh transform. Tercer (talk) 22:45, 17 December 2025 (UTC)[reply]

I think if it is going to be redirected to integral transforms then it should be mentioned in the article. EulerianTrail (talk) 01:39, 18 December 2025 (UTC)[reply]

Then do it. I don't think it is worth mentioning. Tercer (talk) 10:33, 18 December 2025 (UTC)[reply]

I agree with @EulerianTrail: if it redirects to integral transforms, it must be discussed in that article. However, I also do not think it should be mentioned in the integral transform article. Which is I think the best way forward is to delete those articles.

If someone ever creates a well-written article about those transforms, then we can keep it. Alternatively, we can create an article "Integral transforms that are minor variants of classic integral transforms but that some people care about" and list everything there. Malparti (talk) 13:33, 18 December 2025 (UTC)[reply]