Wikipedia talk:WikiProject Mathematics/Archive/2023/May

Parity of zero

There is a discussion at Talk:Parity_of_zero#Deleted_pieces that could benefit from a third perspective. MartinPoulter (talk) 21:00, 1 May 2023 (UTC)

@MartinPoulter: I have restored the status quo ante and encouraged the other editor to engage on the talk-page; I would also like to encourage you to engage constructively on the talk-page (e.g., by discussing substantive points raised by LdV rather than proceduralism). To everyone else, it is still probably the case that a few more eyes on the page would be helpful. --JBL (talk) 22:02, 1 May 2023 (UTC)

Expanding the engineering mathematics page

Hi, I am wondering if I could expand the engineering mathematics. I'm hoping to hear from people here as to the recommended structure. I was thinking a section for each major topic, a brief history of each, a short summary of the concept, and a list of the applications and other wikipedia pages that go deeper.

Thanks :) TattersallOriginal Duke Of Earl (talk) 01:19, 1 May 2023 (UTC)

I guess that you are talking of the page Engineering mathematics. This page is rather short, and certainly deserves to be expanded. However, this is a very difficult task, and I am not sure that there are sufficiently reliable sources for the modern evolution of the concept. In fact, before computers, the mathematics used by engineers were well defined, and there was many textbooks of "mathematics for engineers". However, since the rise of computers, the mathematics used by engineers depend dramatically on their speciality, and cover together virtually all mathematics. For example, discrete mathematics are fundamental for engineers in computing, and were not considered before as engineering mathematics. In other words, with the multiplication of the engineering fields, I am not sure that "engineering mathematics" remains a relevant encyclopedic concept. D.Lazard (talk) 09:38, 1 May 2023 (UTC)

@D.Lazard I agree with your point that engineering mathematics is nearing a redundancy. But I imagine the page to instead reflect the topics that undergraduates should expect to cover. Whilst graduate engineers, maybe the majority, use the range of mathematical concepts far less than they once did because the computer allows for much of the maths to be forgotten; perhaps in the scope of university studies, the page could be expanded? TattersallOriginal Duke Of Earl (talk) 09:48, 1 May 2023 (UTC)

Umm, you can go to seminars on AI, where speakers will happily go on and on about how homology (mathematics) on graphs can be used to obtain XYZ for some problem PQR. Looking around, I thought I saw undergrads in the room. Is AI a part of engineering, or not? I don't think homology can be "forgotten", since anything ChatGPT would say about it would almost surely be wrong. 67.198.37.16 (talk) 20:59, 1 May 2023 (UTC)

I don’t quite understand? I meant that an arguable majority of engineers go into the industry where they don’t use signal analysis since uni for their flow meter instrumentation job for example. In that way much of the maths is “forgotten” because it isn’t utilised for their career. But a page that expands on the mathematics engineers should expect to cover before they graduate may be really helpful. :) 14.202.62.220 (talk) 23:05, 1 May 2023 (UTC)

Probably the majority of students won't care as their university program will tell them what they are supposed to study. The question is why such a curriculum needs to be a topic in this encyclopedia. PatrickR2 (talk) 00:05, 2 May 2023 (UTC)

@PatrickR2 I personally believe that knowledge or insight should be available to people prior to them undertaking a degree. Perhaps children in school will avoid or may even choose to pursue a career in engineering because of the resources they find online. Isn't that the purpose of Wikipedia? Hope that helps understanding of my perspective :) TattersallOriginal Duke Of Earl (talk) 00:08, 2 May 2023 (UTC)

I think that, rather than getting drawn into philosophical arguments, you should be bold and make improvements to the article (in keeping with our usual policies like WP:NOR and WP:NOT). JBL (talk) 00:31, 2 May 2023 (UTC)

@JBLI should've prefaced this much sooner which is completely on me. This is my first week on wikipedia, I've only done copy edits and fixing grammar so I was worried if I just went for it I would be screwing it up for someone else :) but I'll go for it ! TattersallOriginal Duke Of Earl (talk) 00:33, 2 May 2023 (UTC)

It can't hurt to find textbooks called things like Mathematics for Engineers, see what topics they tend to cover, and write summaries of that. XOR'easter (talk) 20:50, 3 May 2023 (UTC)

It would probably be reasonable to look at what mathematical coursework engineering students do as undergraduates and then what kind of mathematical coursework is common to popular engineering disciplines (e.g. electrical, mechanical, civil, geotechnical, chemical, aerospace, ... engineering). Niche tools applied occasionally by expert specialists would be out of scope for any reasonable article. –jacobolus (t) 04:17, 2 May 2023 (UTC)

@Jacobolus Definitely, I am currently an undergraduate of engineering in my final year so I am going to use that for inspiration and look into other universities to gauge a general focus. 14.202.62.220 (talk) 04:47, 2 May 2023 (UTC)

Are you (14.202.62.220) the same person as (TattersallOriginal Duke Of Earl)? PatrickR2 (talk) 21:48, 3 May 2023 (UTC)

@PatrickR2 Hi, yes I am, not sure what's going on with my username not showing in my last reply, must've been logged out :) TattersallOriginal Duke Of Earl (talk) 22:37, 3 May 2023 (UTC)

General references

Please see Wikipedia:Village pump (idea lab)#Deprecate future use of general references? I remember seeing this approach to sourcing being more common in math-related articles in the past, so if you have developed any advice or best practices, please join the discussion. WhatamIdoing (talk) 00:20, 13 May 2023 (UTC)

Almgren (1962). "The homotopy groups of the integral cycle groups".

I was trying on improving the reference list in the Almgren isomorphism theorem and I noticed that Almgren (1962) have two versions, that is ver. Topology (Elsevier) and ver. PhD thesis. I added ver. Topology (Elsevier), but I couldn't read ver. PhD thesis, so what should I do with the latter ? SilverMatsu (talk) 00:58, 18 May 2023 (UTC)

Does the journal version suffice to support the statements made in the article? If so, I would replace the reference to the thesis with the reference to Topology, as this has been peer-reviewed and will be more accessible to most readers. Felix QW (talk) 09:43, 18 May 2023 (UTC)

This overview of his work in the AMS notices seems to suggest that the PhD thesis was essentially the same as the version published in the journal, so I suspect that anything from his thesis supporting the Wikipedia article could indeed be found there too. Felix QW (talk) 09:47, 18 May 2023 (UTC)

Thank you for your advice and reference. Since there seems to be more references likes you gave me, so it seemed better to change Almgren (1962) from harv to harvtxt and and insert it in the body of the article, then add more references. --SilverMatsu (talk) 01:52, 21 May 2023 (UTC)

Article stuck in AfC - - Hurwitz spaces

Hi! My article about Hurwitz spaces Draft:Hurwitz space has been stuck in AfC for one month. It makes me sad because I spend quite some time on it. Could someone review it please? Thanks a lot! :) Beranger Seguin (talk) 10:45, 23 May 2023 (UTC)

If you look at the banner created by {{AfC submission}}, you will see Review waiting, please be patient. and This may take 4 months or more,; it's only been one month. -- Shmuel (Seymour J.) Metz Username:Chatul (talk) 12:24, 23 May 2023 (UTC)

Rewriting “Goppa code”

Hello everyone,

First, my name is Foobanana, and I'm a mathematician with expertise in algebraic geometry codes. I want to rewrite the page on algebraic geometry codes, titled "Goppa code" — it's definitely not reader-friendly, and has the added bonus of having a misleading title.

I would like to rewrite this page, and wanted to ask whether or not the rewriting of that page has been taken, since I’m new to editing wiki pages. I'd hate to make a lot of edits if someone else is currently working on a rewrite, even though I know that's unlikely :)

Hopefully I’m posting this in the right forum, but if I’m not then definitely let me know. Foobanana (talk) 01:51, 9 May 2023 (UTC)

Hi, Foobanana. Welcome to Wikipedia.

No page is "taken". You can be bold and edit whatever you want. But here are two caveats. First, you might want to skim the page's edit history, and the page's talk page, to see whether there has been much recent editing and/or argument. Second, despite your asking here, someone may rewrite your version anyway (in a month, year, or decade). Sometimes experts find that aspect of Wikipedia annoying. In my experience, the best way to "defend" against it is to construct the article around the Wikipedia:Reliable sources --- rather your own expertise, which we can't verify anyway --- from the start. Regards, Mgnbar (talk) 11:53, 9 May 2023 (UTC)

Thank you Mgnbar, I appreciate the response and the links you provided — especially the reliable sources page since I’m new :) Foobanana (talk) 01:17, 24 May 2023 (UTC)

Numberphile up for deletion

Numberphile, the most prominent Mathematics YouTube channel, is listed at Wikipedia:Articles for deletion/Numberphile. You may want to a add to the discussion. Salix alba (talk): 17:32, 10 May 2023 (UTC)

I have no opinion on the deletion. But I do think that new followers of Numberphile should be wary. In his video, Powell’s Pi Paradox: the genius 14th century Indian solution, he illustrates the video with a picture of himself made-up to look like the Indian mathematician (whose actual appearance is presumably unknown at this time) and he uses modern mathematical notation (aka Latex) to describe numbers which by his own admission (at the very end of the video) were originally merely given in poetry (verses in sanskrit). JRSpriggs (talk) 19:24, 21 May 2023 (UTC)

That's a different YouTube channel. eviolite (talk) 22:18, 21 May 2023 (UTC)

Yes, thanks for pointing that out. What I should have said is that one of the guest-hosts of Numberphile is Matt Parker the host of Stand-up Maths including Calculating π by hand. And Matt Parker as the host of Mathologer is the one who impersonated the Indian mathematician Madhava. For more on Madhava, see The man who invented calculus: the life and work of Madhava (Lecture 1) by P P Divakaran. — Preceding unsigned comment added by JRSpriggs (talk • contribs)

Matt Parker is not the host of Mathologer. The host of Mathologer is Burkard Polster. —David Eppstein (talk) 17:44, 23 May 2023 (UTC)

OK, then my apologies to Numberphile and Matt Parker. JRSpriggs (talk) 18:03, 23 May 2023 (UTC)

According to Mathologer's YouTube channel's "About": "In real life the Mathologer is a math(s) professor at Monash University in Melbourne, Australia and goes by the name of Burkard Polster.".

What is the point you are trying to make here? This was a thread about an AfD, which closed some time ago. Pop-science youtube channels are not great sources in any situation, even ones with generally good reputations (like Numberphile and Mathologer). --JBL (talk) 19:13, 23 May 2023 (UTC)

I can find no indication from Monash University itself that Burkard Polster has any connection to it. JRSpriggs (talk) 19:19, 23 May 2023 (UTC)

https://research.monash.edu/en/persons/burkard-polster XOR'easter (talk) 19:39, 23 May 2023 (UTC)

And I'm pretty sure that his picture of Madhava came from Wikimedia Commons. XOR'easter (talk) 19:42, 23 May 2023 (UTC)

And where did the Commons get the picture? Surely, they did not use a time machine and go back and take a photograph of him. Is it a photo of a painting done historically? By whom? JRSpriggs (talk) 00:19, 24 May 2023 (UTC)

You know you can look at the commons index page to find the answers to questions like this, right? They got it from a Feb. 2016 Wordpress post, https://agarwaltv.wordpress.com/2016/02/06/madhava-of-sangamagrama-contribution-to-calculus-was-much-before-europeans/ I am skeptical that it passes WP:PORTRAIT, but that should at least make it obvious that the origin of the image is unrelated to a YouTube channel that is unrelated to the one that was proposed for deletion. —David Eppstein (talk) 18:52, 24 May 2023 (UTC)

Thanks to XOR'easter for proposing the deletion of the image because of inadequate sourcing. I would like to point out that there appear to be the faint signs of eyeglasses on the person in the picture which would be an anachronism for Madhava. Commons getting the image from Wordpress does not exclude the possibility that Wordpress got it directly or indirectly from the Mathologer video. Someone dishonest enough to impersonate Madhava might also be dishonest enough to change his own name to Burkard Polster. JRSpriggs (talk) 20:54, 24 May 2023 (UTC)

The Mathologer video was made in 2023. Get off this stupid hobbyhorse about how wrong they are for using their time machine to cause someone else to make a possibly-unfree image seven years earlier that sort of maybe resembles their host if you squint hard enough and don't pay any attention to the dates. —David Eppstein (talk) 21:20, 24 May 2023 (UTC)

+1. --JBL (talk) 23:13, 24 May 2023 (UTC)

Can you please stop? Burkard Polster is a fine mathematician who has done more than nearly anyone else alive to popularize mathematics, first through accessible books and now through an excellent, accessible, long-running YouTube show. His video is not confusing anyone other than you about Madhava from what I can tell. –jacobolus (t) 23:47, 24 May 2023 (UTC)

If you have a problem with this image, the oldest source TinEye finds is from The Telegraph, a Calcutta newspaper, with the caption "A digital image of Madhava drawn up by the Madhava Ganitha Kendram, a voluntary association working to revive his works, with inputs provided by descendants of the mathematician-astronomer". The copyright status of the image is not clear, so it should perhaps be deleted on that basis, but it is clearly not intended to be an impersonation, anachronism, or cultural insult. Here is another 2014 article about the painting, which was commissioned by the Kerala State Science and Technology Museum (KSSTM) in Thiruvananthapuram. My guess is that both the museum and the voluntary association would be happy to have their painting used widely to represent Madhava as an alternative to leaving him "faceless", but it would be worth trying to find their contact info and ask them directly for a copyright release. –jacobolus (t) 23:53, 24 May 2023 (UTC)

You got me on the dates. I was wrong. I apologize to Mathologer (Burkard Polster) for falsely accusing him. And I apologize to you-all for wasting your time with my fevered imagining. JRSpriggs (talk) 04:46, 25 May 2023 (UTC)

Robertson–Seymour theorem

The article titled Robertson–Seymour theorem begins like this:

In graph theory, the Robertson–Seymour theorem (also called the graph minor theorem) states that the undirected graphs, partially ordered by the graph minor relationship, form a well-quasi-ordering.

I wonder about that. My understanding has been that this theorem states that the set of forbidden minors – the minimal elements – is in every instance finite. Is the statement above to be understood as implying finiteness? Michael Hardy (talk) 21:48, 27 May 2023 (UTC) Michael Hardy (talk) 21:48, 27 May 2023 (UTC)

References

Yes. Up to graph isomorphism. It's the "up to isomorphism" part that the "quasi" in wqo entails. —David Eppstein (talk) 22:36, 27 May 2023 (UTC)

Functional decomposition

Hi! Can somebody please have a look at the article Functional decomposition? It collects useful information about several applications of the concept (which does exist e.g. in software and systems engineering), and presents (in section 1) a mathematical theory seemingly intended to cover all applications. My impression is that this theory is pretty nonsensical from a mathematical point of view; I used my favorite tags {{clarify [span]}} to flag some issues. Since there are almost no inline references, I can't judge whether the theory is just poorly presented, or is WP:OR; I guess, the latter applies. - Jochen Burghardt (talk) 17:05, 23 May 2023 (UTC)

IMO, this is pure WP:OR. I have tagged the article inside {{multiple issues}}. I have also PRODed it. As the talk page is empty, it seems that nobody is really interested in this poorly and vaguely written article. If the article is dePRODed, one can nominate it to AfD. Another solution would be to redirect it to Polynomial decomposition, which is the only nontrivial theory on the subject (One of the sources of the latter article is called "functional decomposition", but, as far as I remember, it is only about polynomial functions). D.Lazard (talk) 18:21, 23 May 2023 (UTC)

It's not an article on mathematics, its an article about engineering. The right way to do it is very often bitterly argued on mailing lists and staff meetings. Getting it right means a pay-raise, getting it wrong risks getting fired. The article might feel like OR, but I'm pretty sure the topic will be explicitly discussed in undergrad engineering textbooks. I won't de-PROD it, but I think it would be fair to notify the owning projects (WP:M is not one of them, the WP:M banner does not appear on the talk page.) It would also be fair to remove the lead sentence "In mathematics...". I'll do these two things now. 67.198.37.16 (talk) 00:27, 27 May 2023 (UTC)

The article is now at AfD. See Wikipedia:Articles for deletion/Functional decomposition. D.Lazard (talk) 17:22, 28 May 2023 (UTC)

Ptolemy RM

There is currently an on-going requested move discussion pertaining to Ptolemy at Talk:Ptolemy#Requested move 25 May 2023 that might be of interest to this WikiProject. Walrasiad (talk) 17:11, 29 May 2023 (UTC)

Cone

Cone

Cone
A right circular cone with the radius of its base r, its height h, its slant height c and its angle θ.
Type	Solid figure
Faces	1 circular face and 1 conic surface
Euler char.	2
Symmetry group	O(2) × SO(1)
Surface area	πr2 + πrℓ
Volume	(πr2h)/3

This infobox tells us what the quantities r, h, c, and θ are, but not ℓ. Then it refers to ℓ in a formula. We are told c is the slant height. But the formula makes sense only if ℓ is the slant height. Then in the body of the article, the letter ℓ is used for the slant height and c for the circumference.

(And the callous indifference of many mathematicians to the typographical difference between things like O(2)×SO(1) and O(2) × SO(1) is appalling. What appears above is after I corrected it, changing the former to the latter. Why are mathematicians unaware of the fact that this kind of thing was central to the way Donald Knuth designed TeX, and for good reasons, and that its intended effect does not depend on its being noticed by the reader?) Michael Hardy (talk) 18:32, 29 May 2023 (UTC)

Errors in LaTeX

An error LaTeX

Just a technical problem. I was looking at the article Locally linear graph, but I found one of the sections, and in this section, there is an error LaTeX in the first paragraph that mentions the construction of Kneser graph algebraically. I've looked at the edit source, trying to add space between K and G in $KG_{a,b}$. When I tried to preview my edit, there is no error appeared. I don't understand how did this happen. Dedhert.Jr (talk) 10:03, 18 May 2023 (UTC)

This is probably due to a communication error between servers ("cannot connect to Restbase"). When such an error appear, the first thing to do is to reload the page, or, when editing, to hit again the preview button. In some cases, a wp:dummy edit could be useful for forcing a new compilation of the page ("compilation" is probably not theright technical term). This is probaly the reason of success of your edit tentative. D.Lazard (talk) 10:27, 18 May 2023 (UTC)

This should not be called "LaTeX", lest those who master it think they have learned LaTeX. Genuine LaTeX involves immensely more than the software used here. Michael Hardy (talk) 15:34, 30 May 2023 (UTC)