Wikipedia talk:WikiProject Mathematics

This is a discussion page for WikiProject Mathematics

This page is devoted to discussions of issues relating to mathematics articles on Wikipedia. Related discussion pages include: 3

Please add new topics at the bottom of the page and sign your posts.

Frame (signal processing)

Should the new article titled Frame (signal processing) be merged into Frame of a vector space? Michael Hardy (talk) 21:15, 21 December 2014 (UTC)

A merge does seem appropriate. For what it's worth, I think the new article frame (signal processing) is written in a much clearer style than frame of a vector space. Sławomir Biały (talk) 15:00, 26 December 2014 (UTC)

On a related note, Frame (linear algebra) probably should be a disambig page; in fact, it's already written that way. -- Taku (talk) 23:08, 26 December 2014 (UTC)

Watchlist bug

Is it only me experiencing that this page does not always show up on the watchlist? YohanN7 (talk) 07:03, 25 December 2014 (UTC)

My guess would be that when Wikipedia is busy changes to a page take some time to be reflected on your watch-list. I doubt that updating watch-lists is the top priority of the system. JRSpriggs (talk) 12:29, 25 December 2014 (UTC)

Updating watch-lists is obviously one of the main priorities of the "system". It relates directly to user experience. I also didn't ask if my observation is important. I asked if anyone else has seen it. YohanN7 (talk) 11:31, 26 December 2014 (UTC)

I have not noticed it. But it is unlikely that I would since I rarely look at this page except as a result of it being on my watch-list.

The experience of the general user (who is not an editor) would probably be a higher priority than that of an editor. Only editors are likely to use watch-lists. JRSpriggs (talk) 14:39, 26 December 2014 (UTC)

Editors are likely to be online browsing, reading and editing 100 times more than mere readers per month Just to make clear what is annoying with this bug: I frequently have to type "Wikipedia talk:WikiProject Mathematics" in the search box. (I am a clumsy typist.) I know, I could create a link on my user page. YohanN7 (talk) 14:19, 28 December 2014 (UTC)

...or just type WT:MATH in the search box :) No such user (talk) 18:08, 28 December 2014 (UTC)

Short for WikiTroject MATHematics? Wouldn't work. Wouldn't remember it from one hour to the next. YohanN7 (talk) 18:17, 28 December 2014 (UTC)

And WT:WPM, documented at the top of this page, has one letter less, and is hopefully more intuitive ;). No such user (talk) 10:58, 29 December 2014 (UTC)

I have a lengthy list of links at the top of my talk page (most editors put this list on their user page). One of them is a link to this page. So I could just click on the "talk" link to get to my talk page and then click on my link to this page. Easy. JRSpriggs (talk) 00:44, 29 December 2014 (UTC)

YohanN7, when you look at your watchlist, do you see a link that says "Show bots"? If so, that's your problem. When your watchlist is set to "hide bots", then it hides any page whose last edit was performed by a bot—even if there were dozens of non-bot edits since the last time you looked at it. You can change your watchlist settings permanently at Special:Preferences#mw-prefsection-watchlist. If you're the sort of editor who checks Wikipedia all day, every day, even when you're on vacation, then I recommend setting your watchlist to show everything, even bot edits. Whatamidoing (WMF) (talk) 00:27, 2 January 2015 (UTC)

Thanks, but I have it set to "show bots". When the problem "happens" it is as if I don't have the page on the watchlist at all, even if it is listed in the watchlist, at least, when I go here after a few days suspecting that the watch feature has broken down, the watch-tab is still set to "on", and there may be several new posts on the page. I emphasize that this isn't a big problem, but I find it curious. It has been this way for some time, probably a year. It is browser-independent (IE/Chrome/Mozilla). It is exclusively this page that is affected. YohanN7 (talk) 00:40, 2 January 2015 (UTC)

Navier – Stokes Millennium Prize Problem. Alternative Solution

Well-known crank. See [1]
The following discussion has been closed. Please do not modify it.
Dear members of the world mathematical community! Enyokoyama (talk) (15:12, 8 November 2013) has offered the new section http://en.wikipedia.org/wiki/Talk:Navier%E2%80%93Stokes_existence_and_smoothness#Yet_another_solution_proposed.3F As a result of discussing this section http://en.wikipedia.org/wiki/Talk:Navier%E2%80%93Stokes_existence_and_smoothness#Attempt_at_solution.5Bedit.5D has been proposed for improvements to the Navier–Stokes existence and smoothness article: Attempt at solution Classical solutions In 2013, Mukhtarbay Otelbaev of the Eurasian National University in Astana, Kazakhstan, proposed a solution. As an attempt to solve an important open problem, the proof was immediately inspected by others in the field, who found at least one serious flaw. Otelbaev is attempting to fix the proof, but other mathematicians are skeptical. Alternative solutions Terence Tao in 18 March, 2007 announced three possible strategies of an alternative solutions if one wants to solve the full Millennium Prize problem for the 3-dimensional Navier-Stokes equation. Strategy 1 “Solve the Navier-Stokes equation exactly and explicitly (or at least transform this equation exactly and explicitly to a simpler equation)” is used in these works: Navier –Stokes First Exact Transformation (3 pages) Navier –Stokes Second Exact Transformation (5 pages) The author of these brief notes Alexandr Kozachok (Kiev, Ukraine) has offered (in February 2008 – Internet , in 2008, 2010, 2012 – INTERNATIONAL CONFERENCE reports, in November 2013 and February 2014 - INTERNATIONAL journal) two exact transformations to the simpler equations. These transformations are executed by well-known classical methods of mathematical physics. Therefore not only some professionals, but also educational, social and many other sites have republished or paid attention to these works . Read more http://en.wikipedia.org/wiki/Talk:Navier%E2%80%93Stokes_existence_and_smoothness#Attempt_at_solution.5Bedit.5D However the Wiki editors can not deny “Alternative solutions” but only block any information about this work. Therefore let's formulate your position for editing of the “Attempt at solution” section http://en.wikipedia.org/wiki/Navier%E2%80%93Stokes_existence_and_smoothness#Attempt_at_solution 93.74.76.101 (talk) 11:37, 29 December 2014 (UTC)

The above shows that our old friend Continuum-paradoxes (talk · contribs · deleted contribs · logs · filter log · block user · block log) is back (and apparently editing under various IPs). He is no longer limiting his contributions to discussion pages, so it might be good for project participants to keep an eye on Navier-Stokes related articles (and other articles that this crank might attempt to push his OR). Sławomir Biały (talk) 01:52, 30 December 2014 (UTC)

Sławomir Biały, your comment «Well-known crank. See [1]» is an expected first reaction of the mathematician because really it is very difficult to believe that “Helmholtz decomposition is wrong”. However, I wonder why this comment has appeared in the section “Navier – Stokes Millennium Prize Problem…” and later 2,5 years after discussion [1] with your active participation? Now, it is better to give another reference( http://analysis3.com/Helmholtz-decomposition-contradictions-pdf-e117376.html) where ideas of the author are covered more strictly. Besides, mathematician should find arguments for a refutation of the claim “Helmholtz decomposition is wrong”. Therefore, your emotions are perceived as a lack of any arguments for this refutation. 93.74.76.101 (talk) 19:39, 12 January 2015 (UTC)

Recent activity at Talk:Quantum Mechanics

Hi!

There has been a storm of activity the past week (by few authors). I think we need more to chip in since the article is (ought to be) pretty vital in physics (and mathematics by extension to today's math-infested QM applications). The interested could perhaps have a look at Talk:Quantum mechanics#1920s quantum mechanics not obsolete. YohanN7 (talk) 11:59, 29 December 2014 (UTC)

WikiCup 2015

Hi there; this is just a quick note to let you all know that the 2015 WikiCup will begin on January 1st. The WikiCup is an annual competition to encourage high-quality contributions to Wikipedia by adding a little friendly competition to editing. At the time of writing, more than fifty users have signed up to take part in the competition; interested parties, no matter their level of experience or their editing interests, are warmly invited to sign up. Questions are welcome on the WikiCup talk page. Thanks! Miyagawa (talk) 21:53, 29 December 2014 (UTC)

Quaternion rotation biradial

This is the one of the most extreme articles I have seen, It's too long to read, so I can't say anything except that I strongly doubt that it belongs in an encyclopedia. YohanN7 (talk) 18:33, 1 January 2015 (UTC)

The lead could be the lead of an article in Wikipedia, if a notable concept. The claim that Hamilton used it would not be sufficient for notability, even if verified. Perhaps it might fit in Wikibooks or Wikiversity. — Arthur Rubin (talk) 19:49, 1 January 2015 (UTC)

I agree with Arthur--the level of detail in the article is more appropriate for a monograph or textbook, so Wikibooks or Wikiversity seem reasonable destinations. Based on a quick GScholar search, the quaternion biradial is not a notable concept. The concept is perhaps worth a summary in Quaternions and spatial rotation. --Mark viking (talk) 23:53, 1 January 2015 (UTC)

This is a particularly egregious example of the walled garden of geometric algebra content on Wikipedia. It's been clear for awhile that this garden could do with some pruning, but someone really need to make it their mission to do that. And, also, collaborate with the GA people too—some of them are a little wacky. We do have some semi-active editors User:JohnBlackburne and User:Quondum who would probably be good at this, but who really has the time and patience for such a task? I, for one, am willing to leave these things be. Sławomir Biały (talk) 00:38, 2 January 2015 (UTC)

Woo-hoo! It's so long, it is a mission just to scroll through it. My guess is that it is a transcription of a thesis or some papers or textbooks (the comments on the talk page seem consistent with this); it seems too far-ranging and detailed to have been freshly created from multiple sources as an article. My reaction is that it could be simply deleted, as I agree that it does not belong in WP as an article. It has been written recently (since April 2014), in its entirety, by a single editor. I don't feel the impulse to do anything but point out to the editor that this sort of article is not what WP is about. —Quondum 04:33, 2 January 2015 (UTC)

Further to that it looks like one of the many things dreamed up in the 19th century which was superseded by geometric and/or matrix algebra when they were developed. It's worth a mention, as a stub-like article which acts as a brief reference for anyone looking for it, or within another article if one's found suitable. The rest just doesn't belong, at least not on WP.--JohnBlackburne^words_deeds 05:21, 3 January 2015 (UTC)

Yeah, it seems like this article should be deleted and/or stubified by someone who thinks they can do it justice. Rschwieb (talk) 17:12, 7 January 2015 (UTC)

---

I have copied the above to the articles talk page and notified the creator. YohanN7 (talk) 22:09, 7 January 2015 (UTC)

List of matrix decompositions

Interpolative decomposition is a new article. Because it is an orphan, I thought maybe list of matrix decompositions should link to it. But that doesn't exist. Should it? Michael Hardy (talk) 22:45, 2 January 2015 (UTC)

Yes. -- Taku (talk) 00:39, 3 January 2015 (UTC)

There's an article, matrix factorization. YohanN7 (talk) 05:10, 3 January 2015 (UTC)

Citing a preprint

(I am posting this here rather than at Wikipedia talk:WikiProject Polyhedra because that project is pretty well inactive.)

Johnson, N.W.; Geometries and transformations (2015) is actively being cited in many articles on polyhedra and related topics, in a sudden flurry of activity. Tomruen (talk · contribs) writes on his talk page that it currently exists only in PDF preprint form but it has been accepted for publication. I have in my possession an earlier draft which was circulated many years ago, and just a couple of weeks ago began removing references to it which had appeared in many of these articles. Suddenly, these are being supplanted by references to the anticipated 2015 publication. Based on past history, I am not confident that the wait for publication will in fact be a short one. Are we happy to accept Tom's word on this? — Cheers, Steelpillow (Talk) 11:19, 6 January 2015 (UTC)

I've had PDF access to the manuscript since 2011 with its final draft submitted in March 2014, and accepted in September 2014, and is in process of being reformatted with minimal content changes. I agree a preprint is problematic on verifiability. I take full responsibility if there are delays in print dates, and I'll update all reference usages as needed on final publishing. I've tried to include exact references on specific facts, and sections and titles should be fixed, but cited page numbers will likely shift a bit. Tom Ruen (talk) 21:30, 6 January 2015 (UTC)

I see not so much a problem with citing a preprint to an expert, but rather that the preprint doesn't seem to be publicly accessible. A link to it might be a valuable addition, but not a reference that is only in private circulation. Sławomir Biały (talk) 12:50, 6 January 2015 (UTC)

I've looked into this a little more, and I don't think things are quite that simple. See, for instance, 8-demicubic honeycomb. This reference has been there for a number of years, so presumably Tom Ruen relied on it to write the article. Only recently does it seem that he has updated the dates on that reference, presumably in anticipation of its imminent publication, although we can't really be sure. In an academic setting, it is necessary and appropriate to cite the sources that one uses, whatever their publication status. That seems to conflict slightly with WP:V in this case. However, I think we should allow the reference to stay there to avoid any appearance of plagiarism. Hopefully it truly will be published soon, and this whole affair will become a non-issue. Anyway, just my 2c, so YMMV. Sławomir Biały (talk) 13:27, 6 January 2015 (UTC)

I have the suspicion that a lot of the references on our polyhedra pages are pro forma "cite something generic on polyhedra because a Wikipedia article needs to have citations" rather than being specific to the subject of the article and the information they are supposedly sourcing. E.g. we have a lot of references to Coxeter's Regular Polytopes (a fine and relevant book) but without any page numbers or other identifying information that would tailor the reference to the article it appears in. So a preprint with a generic title that nobody can access is especially problematic, regardless of the reliability of its author. —David Eppstein (talk) 16:15, 6 January 2015 (UTC)

I agree entirely. I have noticed too that any challenge to some fanboy's favorite factoid tends to result in a flurry of such citations, typically also to self-published web material. There is much that needs attention. Now that we learn that Johnson's book is not yet in its final form but still being "reformatted with minimal content changes", I am even less happy about pretending on most every polytope page that it will be published this year. And what on Earth does it mean for a Wikipedia editor to "take full responsibility"? Whatever happened to biding one's time? — Cheers, Steelpillow (Talk) 22:20, 6 January 2015 (UTC)

Eyes requested on Catalan number

There is a small-scale edit war at Catalan number and I would be grateful if another editor would take a look at the recent edits there. Thanks. (I will probably not be able to make any substantive edits in the next 2 weeks or so.) --JBL (talk) 03:04, 8 January 2015 (UTC)

Wikipedia talk:Articles for creation/François Fages

Hello mathematicians. I have added some sources to this old AfC submission, and moved changed the self-references to publications. Is this a notable mathematician, and should the page be moved to mainspace? —Anne Delong (talk) 04:14, 9 January 2015 (UTC)

Help

Here is quote I have been having a hard time understanding in my research:

"Figure 4 shows the cumulative volume of erupted material versus time for the northern Cordilleran volcanic province; the slope is a qualitative measure of the overall rate of magmatism (km³/m.y.). Although the rate of magmatism has varied substantially through time, there is no correlation between the rate of magma production and the number of active centers during any interval of time (Edwards and Russell, 1999). Initially (20 Ma) volcanism was sporadic, producing small volumes of material. The eruption rate increased markedly (e.g., ~10^–4 km³ yr^–1) when volcanism began at Level Mountain at 15 Ma. When Mount Edziza began to erupt (ca. 7 Ma), rates of magmatism for the northern Cordilleran volcanic province increased to ~3 × 10^–4 km³ yr^–1 (Fig. 4). Between ca. 4 and 3 Ma a magmatic lull appears to have ensued; subsequently rates of magmatism have remained relatively constant at 10^–4 km³ yr^–1. Current rates of magmatism for the northern Cordilleran volcanic province are much less than those estimated for Hawaii (10^–1–10^–3 km³ yr^–1; Shaw, 1987) or the Cascade volcanic arc (0.2–6 km³ yr^–1; Sherrod and Smith, 1990)."

Can someone explain to me what these numbers mean (e.g. ~10^–4 km³ yr^–1) in a more simple format? Volcanoguy 02:14, 10 January 2015 (UTC)

In this context, "~" means "about" (roughly, approximately). "10^–4" means one divided by ten four times, that is, ${\frac {1}{10\;000}}$. "km³" means cubic kilometres of magma, i.e. a billion (1 000 000 000) cubic metres (although usually not in the form of a cube, but spread out more horizontally). "yr^–1" means "per year" (probably averaged over some lengthy period of time). So this example translates to "about 100 000 cubic metres of magma per year". JRSpriggs (talk) 11:05, 10 January 2015 (UTC)

Yes, in more commonly used units, 10^–4 km³ yr^–1 means that the volcano(es?) is releasing 100 million liters (or 26.4 million gallons) of matter (magma?) per year. FireflySixtySeven (talk) 11:45, 10 January 2015 (UTC)

Incidentally, there is the Wikipedia:Reference desk/Mathematics, where questions of this sort will be answered quicker than here. It is usually also interesting to read other peoples questions and their answers over there. YohanN7 (talk) 19:34, 10 January 2015 (UTC)

Wikipedia talk:Articles for creation/Green's function number

Dear mathematicians: Is this old AfC submission about a notable topic? The references are not on line, but perhaps someone here at this project can tell if these are appropriate. —Anne Delong (talk) 17:29, 10 January 2015 (UTC)

This article has been accepted, but it still needs a bit of cleanup and some more references. Primefac (talk) 18:42, 10 January 2015 (UTC)

Thanks, Primefac. —Anne Delong (talk) 15:21, 12 January 2015 (UTC)

Betti numbers and torsion coefficients

Hi,

I have started a discussion at Talk:Homology (mathematics)#Betti numbers and torsion coefficients on how to present these topological invariants. All contributions gratefully received. — Cheers, Steelpillow (Talk) 13:56, 12 January 2015 (UTC)