Wikipedia talk:WikiProject Mathematics/Archive/2010/May

Promotional essay articles prodded
User:Gertbuschmann has recently written two essay articles, Mandelbrot and Julia set landscapes and Field lines of Julia sets, which seem to be (a) original research and (b) intended to promote the author's fractal art web site. I have prodded both. Gandalf61 (talk) 12:48, 20 April 2010 (UTC)


 * Would it be appropriate to move some of the content to the image description page instead? Sławomir Biały  (talk) 12:56, 20 April 2010 (UTC)


 * The ideas aren't actually novel, so not really WP:OR. Properly referenced content could go into Julia set or fractal art. -- Radagast 3 (talk) 04:42, 21 April 2010 (UTC)


 * The mathematical content from Mandelbrot and Julia set landscapes is already in Julia set, in the section The distance estimation, which was inserted by User:Gertbuschmann at the same time as he wrote the promotional article . It still seems clear to me that the only reason for having a separate article is to promote Buschmann's web site and provide a gallery for his fractal art. The images are very nice, but Wikipedia is not the right place to promote them. As you have removed the prod, I think this article should now go to AfD. Does anyone else have views on this ? Gandalf61 (talk) 08:54, 21 April 2010 (UTC)


 * If it went to AfD, I'd !vote to move any relevant content into Julia set (although it mostly seems to be there already) and into fractal art (where it certainly could fit well), adding references such as Peitgen & Richter, The Beauty of Fractals.
 * I replaced the PROD on Mandelbrot and Julia set landscapes by a set of cleanup tags, but I've just noticed the author has removed them without discussion, as well as dePRODing the other article. -- Radagast 3 (talk) 11:47, 21 April 2010 (UTC)


 * His programs's got a rubbish UI as well. --Matt Westwood 18:26, 21 April 2010 (UTC)


 * I can't see how that is relevant to this discussion. It's always worth remembering that authors of articles do have the technical ability to read this page, and that tact can make difficult situations less unpleasant for everyone involved. &mdash; Carl (CBM · talk) 19:39, 21 April 2010 (UTC)


 * Update: The mathematical content of the two articles has now been merged into Julia set. What was left from one article has been deleted at the author's request, and the remains of the other have been usefied. However, User:Gertbuschmann has now created another new essay/textbook-style article at Images of Julia and Mandelbrot sets, which is as yet unreferenced. Gandalf61 (talk) 11:29, 24 April 2010 (UTC)


 * More update: I have tried to explain the relevant Wikipedia policies to User:Gertbuschmann, but he has made no attempt to add sources or make any other improvements to Images of Julia and Mandelbrot sets. As he seems to have no intention of providing sources for his contributions, I have nominated the article for deletion - discussion at Articles for deletion/Images of Julia and Mandelbrot sets. Gandalf61 (talk) 09:48, 30 April 2010 (UTC)

Help request: Ronald Brown (mathematician)
Hi. This article was up for deletion at WP:CP today as part of a WP:CCI. He seemed like a notable fellow, I had enough time, and the extensiveness of this particular problem was difficult to determine, so I've created a new article as a "start" (rather than deleting it). But I am not able to do him justice...or anything near, really. :) If somebody who has the background to review this (and this) could at least explain in what areas this fellow works, I'd be very grateful. :) --Moonriddengirl (talk) 20:12, 23 April 2010 (UTC)
 * Looks like he mostly works in abstract algebra, particularly algebraic topology. 69.228.170.24 (talk) 09:55, 26 April 2010 (UTC)
 * Actually he is a fairly well known category theorist. (Often "Ronnie", and there are other Ron Browns, none of which helps.) His contacts with Grothendieck put him on the map in terms of general interest. There is a lot of self-published stuff of his on the University of Bangor, and he is the sort of person about whom a decent WP article can be written, by sifting through. Charles Matthews (talk) 11:09, 26 April 2010 (UTC)
 * Thank you! Would I be accurate and supported by his publications list if I revised the lead to read: "Ronald Brown is an English mathematician who works with category theory and algebraic topology"? Fortunately, I don't have to know what those are. :D --Moonriddengirl (talk) 11:14, 26 April 2010 (UTC)


 * That would be OK - if he is somehow Welsh by identification I suppose we'll be told. Charles Matthews (talk) 10:18, 30 April 2010 (UTC)

Math Overflow
Does anyone here monitor the mathoverflow.net site? I happened upon it, and there is a fair amount of technical criticism there of our pages. Which could be helpful in a nitpicky, fact-checking way, certainly. (Amusingly they seem to have a site policy "don't start discussing whether WP is an RS".) Charles Matthews (talk) 20:27, 26 April 2010 (UTC)


 * I check it every day. The problems discussed are generally at a rather high level, and most of our articles on that level are indeed lacking. I have seen several occurrences of recommendations of wiki's articles though. RobHar (talk) 00:28, 27 April 2010 (UTC)


 * See Talk:Constant sheaf for a specific recent instance of criticism. RobHar (talk) 20:42, 3 May 2010 (UTC)


 * Yes, that's a good example. Charles Matthews (talk) 09:04, 4 May 2010 (UTC)

Till Tantau
His bio is up for deletion. He is a math prof, although better know for his TeX work. (Taco Hoekwater is also up for deletion, should you care about TeX authors' bios.) Pcap ping  23:29, 3 May 2010 (UTC)

nLab
I've created a new stub article called nLab, and I've put links to it into ten other articles. Work on it. Michael Hardy (talk) 18:53, 4 May 2010 (UTC)

LaTeX \sim rendering as tilde in html
I've just noticed at the end of Random effects model that the LaTeX  is being rendered in HTML as a tilde, e.g. $$X \sim N(0,\sigma^2)$$ – on my set-up at least that looks like X~N(0,σ²) but in a serif font in which the tilde is so small and high up as to look like little more than a wavy serif. Has it always done this? I know that I can force PNG rendering, but i would have thought that the authors of texvc should know that a tilde isn't an acceptable rendering of. Is there somewhere I should report this? Qwfp (talk) 20:34, 3 May 2010 (UTC)


 * Try this: $$X \sim N(0,\sigma^2)\,$$. I pretty much just add \, to the end of every math formula to avoid issues like this and to keep formulas looking consistent.--RDBury (talk) 21:31, 3 May 2010 (UTC)
 * Please don't do that. If people want all formulae to be displayed as PNGs they can set their preferences accordingly. If a formula can be displayed reasonably well in HTML, then you should allow it to be. HTML works more widely and uses less bandwidth. You should only force it to display as an image if it doesn't work as HTML or it looks really weird compared to nearby formulae that can't display as HTML. --Tango (talk) 22:50, 3 May 2010 (UTC)
 * The "really weird" thing is what I'm trying to fix. Nearly every math article is going to have some formula that can't be done in html, and having mixed formats on the page makes the article look like a ransom note. If I do see an article that's using html consistently then I'll leave it that way, but I don't see them often. For inline formulas I usually force html by just writing the formula in html, again so the mixed fonts don'tclash.--RDBury (talk) 13:55, 4 May 2010 (UTC)
 * Yes, it should be reported as a bug in texvc. I can do that if you aren't familiar with http://bugzilla.wikimedia.org &mdash; Carl (CBM · talk) 22:04, 3 May 2010 (UTC)
 * I'm not at all familiar with bugzilla, so I'd be most grateful if you could report this, Carl. Regards, Qwfp (talk) 22:17, 3 May 2010 (UTC)


 * Sure. It's at 23397 now &mdash; Carl (CBM · talk) 22:47, 3 May 2010 (UTC)
 * Thanks Carl! I didn't realise html had a "sim" entity. So it should be possible to do better without resorting to PNG. Qwfp (talk) 22:56, 3 May 2010 (UTC)


 * Even if it wasn't an entity, the sim operator has a Unicode point 223C, although not everyone may have the right fonts. But since HTML 4 is over 10 years old, anything in it should be visible to almost anyone. &mdash; Carl (CBM · talk) 23:01, 3 May 2010 (UTC)
 * Experimental copy-pasting from List of XML and HTML character entity references: ∼ ≠ ~ ! Qwfp (talk) 23:10, 3 May 2010 (UTC)
 * Actually, I was wrong: the current rendering is this character: 02dc. No wonder it looks so bad. I thought it was just a font issue, until I checked the bytes that actually make up the character that texvc uses. &mdash; Carl (CBM · talk) 00:05, 4 May 2010 (UTC)

(ui) Is texvc being maintained at the moment? I've noticed that the MathML option has been "experimental" since I've started editing and there doesn't seem to have been any progress in getting it fully implemented. I just assumed that since most WP articles don't use formulas, the texvc issues are near the bottom of the list of priorities.--RDBury (talk) 13:56, 4 May 2010 (UTC)


 * It is maintained; someone has already put in a patch for the bug about the \sim operator. On the other hand, the maintenance focuses primarily on bug fixes, for various reasons. I have been waiting for the STIX fonts to come out before asking about it. The way Wikimedia development works, anyone with the programming skill could work on the math system. There was a proposal for the google summer of code to rewrite texvc in python, but I don't think it was accepted.


 * One option would be for Wikimedia to switch to jsMath instead of texvc for generating non-image TeX output. This is the system that MathOverflow uses, and it seems to be very actively maintained. &mdash; Carl (CBM · talk) 15:32, 4 May 2010 (UTC)
 * Glad this has been patched so quickly. 'Scuse my ignorance, but how long is it likely to be before the patch comes into effect on en.wikipedia? Will we need to purge all the affected pages after is does? Qwfp (talk) 18:39, 4 May 2010 (UTC)


 * I have been envying PlanetMath for their use of jsMath for quite some time. What are the odds that we could get this? It's funny that those smaller sites have the cool featuret because they are specialised, and we have to live the current situation that encourages coding all formulas in standard wikicode where feasible. Hans Adler 19:04, 4 May 2010 (UTC)


 * It was very easy for me to get jsmath working with a local mediawiki install just now. The first step would be to convince the site admins (e.g Tim Starling) that it's worth adding. The actual code that would need to be written is trivial: all the work is in setting up everything on the webserver. It would also require testing to make sure it is able to render all the math that texvc output; I found a few issues already that would need to be fixed before it could be made live. But in principle this should be straightforward but time consuming. &mdash; Carl (CBM · talk) 20:26, 4 May 2010 (UTC)


 * In my experience, the jsmath on the PlanetMath site takes a very long time to load. I'm not sure whether this has more to do with the site or with jsmath. Jim (talk) 22:21, 5 May 2010 (UTC)
 * It looks to me as if the rendering happens with JavaScript on the client side, so the rendering delay would be a client side problem. I don't like the delay either, but it looks great. Hans Adler 22:38, 5 May 2010 (UTC)

GA nomination
Long and short scales has come up for GA review but so far no one has done a review. I'm not totally sure this is really a math article rather than linguistics but it's been put under math.--RDBury (talk) 19:51, 5 May 2010 (UTC)


 * It is definitely linguistics, not mathematics. JRSpriggs (talk) 23:48, 5 May 2010 (UTC)

Periods
A notability tag has been placed at Period (number). Here's the Google scholar result periods author:zagier author:kontsevich. I think it's notable enough for its own article. Bethnim (talk) 09:48, 11 May 2010 (UTC)


 * Probably. The definition is something a logician would come up with, though. The conjecture is of some interest, but is not formulated that clearly. The problem with taking the content of about one paper (I'm not clear whether that is a true description, but it expresses what I mean) and putting it forward as a Wikipedia topic, is that "notability" in the sense of being "serious" is not best judged by any metric applied to recent literature. At present, if we really lack the article on "period" in the sense of algebraic geometry (what we have is period mapping), in which the Kontsevich-Zagier ideas would naturally form a section on recent ideas, it is much harder to see what is going on. So I find the article too "presentist" (overly concerned with the buzz of current research) as it stands. Charles Matthews (talk) 10:19, 11 May 2010 (UTC)
 * I looked over the list of the (numerous) papers citing the article "Periods" and found that there is an even spread over the past decade, not just "buzz of current research". There is even a paper from 1999 even though "Period" appeared in 2001!  I think a separate page is justified given the article's influence.  Tkuvho (talk) 10:28, 11 May 2010 (UTC)
 * I still think Kontsevich–Zagier period conjecture would be a better title. If there is influence, it is apparently in the programmatic way certain parts of number theory fall into. Charles Matthews (talk) 11:55, 11 May 2010 (UTC)
 * How many people referred to such a conjecture? Tkuvho (talk) 12:00, 11 May 2010 (UTC)  The object itself that they introduced (namely, a reasonably "natural" intermediate field between Q-bar and R) appears to be of great interest, beyond the particular conjectures one formulates here.  Tkuvho (talk) 12:02, 11 May 2010 (UTC)
 * It is talked about that way - for example on mathoverflow.net; but who knows what is in print? I still think there is a certain problem about the formulation, which if you like is a writing problem. Just finding a way to define a countable field isn't specially notable at all, a mere exercise: the hypothetical decision algorithm is the interest, though it won't be within reach until transcendence theory improves remarkably. The paper was a preprint; it has found its way into a Springer book, so is notionally peer-reviewed. Again, if you isolate the conjecture, it is easier to feel that the issue of peer-review is not crucial. I have to say that I had similar issues in trying to reference motivic zeta function, sort of related in area/feel, for which the original source turns out to be a preprint nearly a decade old. We have the choice of awarding "notability" to some rather hypothetical mathematics, but I get worried when the original references are slender. (I'm not worried about the calibre of the mathematicians, but that isn't usually taken as decisive.). Charles Matthews (talk) 14:03, 11 May 2010 (UTC)
 * I notice that some of the papers in the literature refer to this as Periods in the sense of Kontsevich and Zagier. This may be preferable to the current non-descript title.  The term appears no longer to be a neologism, which is all that matters as far as wiki policy is concerned.  Tkuvho (talk) 14:43, 11 May 2010 (UTC)
 * (ec) (Before the comment adding Periods in the sense of Kontsevich and Zagier. I don't feel like rewriting my comments to refer to that.)
 * As the one who added the notability tag, I'll make some comments before going on a Wikivacation. I may have added the wrong tag, but I have the following concerns about the article.  This article first came to my attention when it was added to Template:Number systems.
 * I don't think "number" is the proper disambiguation, as most "periods" of a periodic function are numbers. Perhaps Period (Kontsevich and Zagier)?.   (Although, if it is the same concept as the period of a rational system of differential equations, that might be a reasonable approach.)
 * The concept may be used (although not by me), but is this really a common use of the word "period" in Mathematics. And is "period" the most common term to refer to the concept?
 * Detailed comments:
 * Reference [2] (in the lede) seems to assume that the coefficients of "Igusa local zeta function" (which also appears to be different than Igusa zeta-function) is a "notion that algebraic geometers have studied since Riemann and Weirstraß." They (and the reviewers) may not be an experts in the "history of algebraic geometry", even if experts in "algebraic geometry".
 * The Newton-Leibniz formula seems to be a red-link; I'm not sure which formula attributed to Newton and Leibniz might be intended.
 * Speculation as to whether the reciprocal of a "period" is a "period" seems relevant. In all other hierarchies of numbers, larger sets have more closure properties than smaller sets.  Here, the set of periods doesn't even seem to be a field.  It almost certainly isn't algebraically closed, as we note that $$\Gamma(p/q)^q$$ is a period, without reference to $$\Gamma(p/q)$$.  This section may be more relevant to whether it should be included in the template, rather than the article, itself.
 * I'm going to add the refimprove tag; the only inline references are in the lede, and there's no indication if the rest of the article is taken from those references (probably reference [1]).
 * Please feel free to copy this to the article talk page. There doesn't appear to have been any comments there, and I probably should have brought it up there first.  — Arthur Rubin  (talk) 14:57, 11 May 2010 (UTC)

Comments to Rubin. Period (Kontsevich and Zagier) improves what we have now; it is an idiosyncratic use. There is just one type of Igusa zeta function, AKAIK. The business of the reciprocal is not that relevant, IMO; it is in the nature of a remark that the set of periods being countable, the field they generate is also countable, but do they use the structure? The business of the fields seems to be lifted from the PlanetMath article referenced; should be rewritten. Charles Matthews (talk) 15:35, 11 May 2010 (UTC)


 * R.e.b. has moved the article to Ring of periods. The tag was added, I guess because Template:Number systems linked to the article and Arthur Rubin objected to this because they are not algebraically closed or a field. Whether they constitute a "number system" is debatable I suppose, but I don't think they are any more or less a number system than any of the other things on that template. This is where the notability question comes in - are they notable enough to appear on that template? Bethnim (talk) 16:48, 11 May 2010 (UTC)


 * I wouldn't include them on that template. I feel navigational templates of that kind exist on tolerance anyway, for cases where the category system is not the right solution for an appreciable set of readers. But calling the periods a "number system" is already too much of a stretch for me. Charles Matthews (talk) 17:41, 11 May 2010 (UTC)

Discussion of the scope of Wikiproject Statistics
As Wikiproject statistics is, in a sense, a daughter project of WP:Mathematics, your collective opinions about the scope of WP:STATS is requested at Wikipedia_talk:WikiProject Statistics. Thank you. -- Avi (talk) 12:19, 11 May 2010 (UTC)

Core articles
We currently have a list of core mathematics articles at WikiProject Mathematics/Wikipedia 1.0. It looks like it's been years since anyone has looked at this with a critical eye and the article ratings and statistics are out of date. My first question is whether we need our own list when there is already a (somewhat different) list at WP:CORE which is better maintained. There are also the WP:VITAL categories which seem to serve more or less the same purpose. If no one has a compelling reason to keep our list then I'll go ahead and replace it with a link to the math section in WP:CORE. If we decide to keep our own list, I think there should be some discussion as to what purpose it serves, how big it should be, and what should be the criteria for inclusion.--RDBury (talk) 16:57, 12 May 2010 (UTC)
 * I replaced the section with a link. Our current tally of ratings for core articles is 5 B's and 1 B+.--RDBury (talk) 15:17, 14 May 2010 (UTC)

Exaom
See Exaom. So should we just "prod" this thing? Michael Hardy (talk) 05:20, 14 May 2010 (UTC)


 * It is not mathematics, so I changed the category from Mathematics to Buddhism. Let them decide whether to delete it or not. JRSpriggs (talk) 07:08, 14 May 2010 (UTC)

I prodded it. Sławomir Biały (talk) 11:12, 14 May 2010 (UTC)

Opportunity for project to help save: Alwin Reinhold Korselt
I recently removed the PROD on this one because I think there are sufficient sources out there to improve the article. As I don't have a clue about the history of Mathematics, maybe someone here can tackle this. Thanks--Mike Cline (talk) 15:05, 11 May 2010 (UTC)
 * He does seem notable - contributions to logic and a controversy with Frege and Hilbert on foundations. (The contribution to number theory looks very much like an exam question I once did, though.) Charles Matthews (talk) 15:27, 11 May 2010 (UTC)

I did some googling and was able to establish that he did indeed exist and he seems reasonably notable - but I didn't feel comfortably removing the notability tag until someone who really knows what they're talking about comes along. Instead I just put in an infobox so as that it'd at least look like a biography. --Paul Carpenter (talk) 12:44, 14 May 2010 (UTC)
 * Actually, scrap that. I moved the article to a more sensible location (per the manual of style) and took away the notability tag. I figured that if his contributions are worth mentioning in other articles then he meets the first criterion in the professor test: "The person's research has made significant impact in their scholarly discipline...". However, there are still no sources for the purely biographical data such as his date of birth which are necessary for a decent biographical article. There is still a need for someone with specialist knowledge on this. --Paul Carpenter (talk) 16:01, 14 May 2010 (UTC)
 * Interestingly (for some), the biographical data on Korselt is called "meagre". My German isn't quite up to reading what is said towards the end of that page. Charles Matthews (talk) 17:05, 14 May 2010 (UTC)
 * That's an excellent find. It has appeared in a highly unorthodox experimental form – the floppy disk edition of the journal de:Wittgenstein-Studien – but appears to be reliable. Since my German is in better shape I will try to extend the article a bit. Hans Adler 18:18, 14 May 2010 (UTC)
 * Thankyou very much and well done to all. I've taken away the "stub" and "fact" tags - it's now not a bad article at all. And to think that it was PROD'd just a few days ago! --Paul Carpenter (talk) 20:23, 14 May 2010 (UTC)

I've copied a couple of the references, particularly the one in German, over to the German article so as to return the favour, since our version was originally copied over from theirs. Apparently non-logged in edits have to be approved before they are visible on the German Wikipedia, so I'm hoping that the tiny bit of German I had to use wasn't too awful. Paul Carpenter (talk) 09:37, 16 May 2010 (UTC)
 * Thanks. The German Wikipedia doesn't like over-referencing and what they consider unnecessary footnotes, so I have fixed that. The accepted practice when you add a fact from a source that the average reader wouldn't want to consult is to give the source in the edit summary. Hans Adler 10:11, 16 May 2010 (UTC)

NIST Handbook of Mathematical Functions
...is now published online, as the NIST Digital Library of Mathematical Functions.  Chzz  ►  03:38, 15 May 2010 (UTC)


 * To Chzz: Thanks for the link. I always found the older printed version "Handbook of Mathematical Functions" to be very useful.
 * Do you think we should have a separate article on this work, like we do on some other books such as Gravitation (book) by Misner, Thorne, and Wheeler? JRSpriggs (talk) 09:23, 15 May 2010 (UTC)


 * I guess it's a bit early for that, but we can discuss it in the existing article Abramowitz and Stegun, and then either spawn it off once there is more to say about it or rename the article to Handbook of Mathematical Functions to make it clear that the article covers both. Hans Adler 11:42, 15 May 2010 (UTC)


 * I see now that articles on both versions already exist, see Handbook of Mathematical Functions. Thanks to R.e.b. for improving the redirects. JRSpriggs (talk) 08:40, 16 May 2010 (UTC)

Template:SpecialChars
I have a funny sense of deja vu asking this, but I figured I should try to gauge the consensus again. Am I correct that SpecialChars does not belong on mathematics articles? I recently just removed it (for the third time) from Set (mathematics). Sławomir Biały (talk) 11:55, 14 May 2010 (UTC)
 * The template is independent of topic of the article, IIUIC it belongs to any article which contains characters not rendering correctly in some popular browser setups. I've never had problems with missing characters myself, but I've seen people removing set-related symbols like ∪, ∩ from articles on the grounds that they do not see them, which would indicate that the template is appropriate on Set (mathematics) where these characters are used.—Emil J. 12:06, 14 May 2010 (UTC)
 * Actually, as I have pointed out on Talk:Set (mathematics), there is no guideline at all regulating the usage of this template. Moreover, the template documentation flagrantly contradicts our own style guidelines.  So I'm eager to see the template go, or be changed into something much less obtrusive (e.g., something that goes at the very bottom of the article rather than the very top).  At any rate, this template is potentially something that, if your understanding is correct, would be put on just about every mathematics article.  So it is obviously important for the project to get some clarity on precisely when it is appropriate (if ever).   Sławomir Biały  (talk) 12:24, 14 May 2010 (UTC)
 * I guess it's not a matter of guideline, but of courtesy. I do not think it would concern "just about every mathematics article": more often than not problematic symbols are written in TeX rather than HTML in mathematical articles, and we probably only have to bother about high-profile articles (like Set (mathematics), I guess) which attract a lot of clueless readership. Anyway, I agree that the template is too obnoxious in the top right corner, (if used at all) it should better go elsewhere, preferably somewhere near the actual occurrence of the special characters it talks about.—Emil J. 12:43, 14 May 2010 (UTC)
 * This should only be a problem with characters that don't show up correctly on some browsers. Looking at the Math and logic section of the special characters box in the Wikipedia edit screen, I see all of − × ÷ ⋅ ° ∗ ∘ ± ∓ ≤ ≥ ≠ ≡ ≅ ≜ ≝ ≐ ≃ ≈ ⊕ ⊗ ⇐ ⇔ ⇒ ∞ ← ↔ → ≪ ≫ ∝ √ ∤ ≀ ◅ ▻ ⋉ ⋊ ⋈ ∴ ∵ ↦ ¬ ∧ ∨ ⊻ ∀ ∃ ∈ ∉ ∋ ⊆ ⊈ ⊊ ⊂ ⊄ ⊇ ⊉ ⊋ ⊃ ⊅ ∪ ∩ ∑ ∏ ∐ ′ ∫ ∬ ∭ ∮ ∇ ∂ ∆ ∅ ℂ ℍ ℕ ℙ ℚ ℝ ℤ ℵ ⌊ ⌋ ⌈ ⌉ ⊤ ⊥ ⊢ ⊣ ⊧ □ ∠ correctly. On the other hand 〈 and 〉 just look like boxes to me so I'm thinking the TeX equivalents should be used instead. In general, the template shouldn't be needed at all in math articles because a TeX equivalent should be used instead of problematic characters, but the issue is what level of extended Unicode is to be considered problematic. It's not practical to use TeX every time we want to add a Greek letter or a minus sign. But people using popular browsers shouldn't need to load special fonts to read a math article. If we can agree on a list of acceptable characters (the named entities in List of XML and HTML character entity references might be a good place to start), and say that if it's not there then use TeX instead, the we should be able to avoid the use of the template altogether.--RDBury (talk) 15:56, 14 May 2010 (UTC)
 * The angle brackets in your counterexample are named html entities: &amp;lang; and &amp;rang;. Also in my browser, these display correctly, and many of the other "acceptable" characters that you offer do not.  So this suggestion, whatever its merits, still will not solve the problem that I had initially asked, since it seems unlikely that there is a symbol set that everyone will find satisfactory.  Sławomir Biały  (talk) 16:57, 14 May 2010 (UTC)
 * What I had in mind was to start with the named entities a take out the ones that going to be a problem for a significant number of users. I'm still on Window XP so I suspect that the reason I can't see the angle brackets is my fonts are out of date. Are there still a significant number of people still using Window XP? WP:MOSMATH says that it's ok (more or less) to use anything on the list of named entities, so if we're both having trouble seeing all of them then perhaps some additional restrictions should be added. There are two extremes, use any Unicode character that exists even though many people won't be able to see them, or keep to ASCII and use up bandwidth with a PNG every time we use a minus sign. I'm hoping there is a reasonable compromise.--RDBury (talk) 18:09, 14 May 2010 (UTC)
 * Just a side note, the second extreme is basically what MathWorld does. So a typical page has dozens of GIF images.--RDBury (talk) 18:45, 14 May 2010 (UTC)
 * I'm using Win XP and Firefox and all the above symbols appear perfectly including the angle brackets. However in Internet Explorer 8 most of the symbols are boxes. So it's not a question of missing fonts or old operating systems. It's just that Internet Explorer is very very crap and Microsoft don't give a damn about mathematics. So I suggest that when people log on to Wikipedia they are met with a message saying that Wikipedia recommends Firefox for viewing special characters as Internet Explorer is hopeless. Open source projects should support each other. Bethnim (talk) 20:38, 14 May 2010 (UTC)
 * What would be useful is if browsers could automatically download fonts from the web if they are needed. The web is nearly twenty years old - why do still have this nonsense ? Bethnim (talk) 20:56, 14 May 2010 (UTC)
 * My (very dusty) IE at least shows − × ÷ ± ≤ ≥ ≠ ≡ ≈ ∞ ← ↔ → √ ∩ ∑ ∏ ′ ∫ ∂ ∆ ⌊ ⌋ ⌈ ⌉ which should be enough for most of the articles that use special math symbols. But for some reason it doesn't show union, ∈, ∅ or ⊆ which is probably the issue with the Set article. WP does have a Help:Special characters page which tells people how to properly set up IE to see these characters, but you have to know where to look and that's kind of the point to the template in first place. It would be nice for us to require people to read it when they log in to WP but keep in mind we're a minority here. So I guess the upshot is my idea won't work since it would be hard to do without basics like ∈. I only see three other options, either PNG everything like MathWorld, leave the special characters in and hope everyone reading a math article knows not to use IE (at least without changing the default font), or leave the template in. Maybe the solution is to make the template smaller. The way it was used in the Set article it was bigger than the diagram that was supposed to illustrate the subject, so it's a valid complaint that it's too obtrusive.--RDBury (talk) 01:36, 15 May 2010 (UTC)
 * The CSS3 standard supports automatic font download, and the feature already seems to be implemented by several popular browsers: Comparison of layout engines (Cascading Style Sheets) (including partial support in IE ≥4.0, if I understand the table correctly).—Emil J. 18:30, 15 May 2010 (UTC)

In my opinion we have waited long enough for a good solution. The pseudo-LaTeX we are using looks horrible when printed and has silly size and baseline problems. Coding everything by hand in wiki code and with unicode is extremely tedious and error prone, doesn't give us enough flexibility, and causes problems with old browser setups. Articles keep getting changed from one style to the other and back. That's no wonder, because apart from different tastes we also have no less than six different options for how mathematics is rendered.

I guess if we don't ask for an end to this madness, and do so several times, we are not going to get it. I think it should really be possible by now to create one, reasonable solution that doesn't require any options, works with the browsers of at least 95% of our users and has a simple fallback such as displaying pure latex source code for the others. I wouldn't consider it a problem if users of some browsers need to install a plugin (e.g. the MathML plugin for Internet Explorer) or download fonts, so long as the server pushes this as I have just seen on the W3C's MathML demonstration page when I visited it with Internet Explorer. Hans Adler 19:50, 15 May 2010 (UTC)
 * A lot of these issues are already under discussion in the typography subproject. I'm really hoping that in the future MathML will be widely implemented enough that these problems can go away by themselves. Paul Carpenter (talk) 14:02, 16 May 2010 (UTC)
 * There is already a MathML option under user preferences but the converter only handles the most basic formulas. To my knowledge, MathML and TeX are similar enough in syntax that it should be possible to write a full converter but someone with the skills (and the time) needs to do it and it looks like no one is volunteering. As I mentioned earlier, we're a minority on WP and I doubt this kind of thing is generally considered a high priority among the people at WikiMedia. (To put things in perspective, Numb3rs gets more than twice as many hits as Number.)
 * I'm asking myself, if we did have an ideal system where math formulas were automatically converted to MathML, then how would we change the wiki-markup. One thing that would change is we wouldn't be kludging HTML and Unicode any more but writing even the simplest expressions in TeX (or whatever math markup language the future will bring). So maybe one thing we can do now is to stop relying so much on on the kludge and start using TeX more since the converter is supposed to be smart enough to convert to HTML on its own. One thing to try for the Set article would be to rewrite the formulas using ∪, ∈, ∅ and ⊆ to the TeX equivalents to see if the results are acceptable.--RDBury (talk) 17:56, 16 May 2010 (UTC)

I tried a sample paragraph - HTML only (original):

The key relation between sets is membership – when one set is an element of another. If A is a member of B, this is denoted A ∈ B, while if C is not a member of B then C ∉ B. For example, with respect to the sets A = {1,2,3,4}, B = {blue, white, red}, and F = {n2 &minus; 4 : n is an integer; and 0 ≤ n ≤ 19} defined above,
 * 4 &isin; A and 285 &isin; F; but
 * 9 &notin; F and green &notin; B.

TeX only:

The key relation between sets is membership – when one set is an element of another. If $$A$$ is a member of $$B$$, this is denoted $$A\ \in\ B$$, while if $$C$$ is not a member of $$B$$ then $$C\ \notin\ B$$. For example, with respect to the sets $$A = \{1,\ 2,\ 3,\ 4\}$$, $$B = \{\text{blue, white, red}\}$$, and $$F = \{n^2 - 4 :\ n \text{ is an integer; and } 0\ \le\ n\ \le\ 19\}$$ defined above,
 * $$4\ \in\ A \text{ and } 285\ \in\ F$$; but
 * $$9\ \notin\ F \text{ and green } \notin\ B$$.

When I view this with the 'Use HTML if Possible' option it renders as HTML instead of PNG, but there there still mismatches in the fonts, e.g. it uses serif which doesn't match the sans serif which is my default font, and it bolds most the plain text. Maybe some of the problems are due to my lack of skill with TeX (feel free to tweak the markup), but it seems like this issue should be a relatively easy fix and would have a better chance of getting done quickly than writing a complete TeX to MathML converter.--RDBury (talk) 18:53, 16 May 2010 (UTC)


 * Hi, the LaTeX to MathML converter already exists since several years, it is called Blahtex. The principal obstacle to its introduction was that wikipedia is not mathml-ready, since it does not produce clean xhtml. The authors seem to have tired to wait and abandoned this project.--LutzL (talk) 11:57, 17 May 2010 (UTC)

How to factor polynomials
What shall be the fate of the new article titled How to factor polynomials? Michael Hardy (talk) 02:21, 17 May 2010 (UTC)
 * .....and now I see that it's not a new article. It sat there for many months as a complete orphan (i.e. no other articles linked to it) until today, when someone added a category tag to it, thereby causing mathbot to notice it and add it to the list of mathematics articles, which in turn caused Jitse's bot to add it to this WikiProject's "Current activity" page, where I saw it listed.  When I checked a few minutes ago the list of mathematics articles and a redirect were the only pages in the article space that linked to it.
 * So maybe mathbot should search more extensively. If an article has certain words or phrases it could pick it up as a possible math article and call it to the attention of humans, who would then decide whether to add one of the math category tags. Michael Hardy (talk) 02:26, 17 May 2010 (UTC)
 * Wikipedia is not a how-to guide. I think it should be transwikied to Wikibooks. -- King of &hearts;   &diams;   &clubs;  &spades; 05:54, 17 May 2010 (UTC)
 * Wikibooks is not a general dumping ground for everything we don't want. One would have to find a specific book that could profit from this material. Hans Adler 12:25, 17 May 2010 (UTC)
 * Wikibooks is not a general dumping ground for everything we don't want. One would have to find a specific book that could profit from this material. Hans Adler 12:25, 17 May 2010 (UTC)


 * But one shouldn't leap to the conclusion that it's a how-to article merely from the fact that its present title starts with the words "how to". Michael Hardy (talk) 10:42, 17 May 2010 (UTC)

I've proposed merging into factorization of polynomials.

Both articles are in deplorable condition. Michael Hardy (talk) 10:53, 17 May 2010 (UTC)
 * Merging improving looks like good idea.--Kmhkmh (talk) 12:42, 17 May 2010 (UTC)

Householder's method - input welcomed
User:Gauge00 added a section titled "Another derivation of Householder's method" to Householder's method. I removed it, because the article already has a derivation section, and I do not think that the new section (a series of lengthy algebraic manipulations offering little or no insight) improves the article. Gauge00 reinstated the section with the justification "I think it is personal or individual preference to determine which one is more concise and clearer ... You are not the sole, unique reader, unique referee". So input from other editors is welcome at Talk:Householder's method. Gandalf61 (talk) 11:59, 17 May 2010 (UTC)

Call to Arms for Wikipedia's sister projects
Sometime around the summer of 2009 I had stopped developing any Wikipedia articles seriously. Fundamentally this was because I found I disagreed with the community about to what extent proofs should be covered in wikipedia articles. I don't want to start a long conversation about my reasons, suffice to say topics like Extreme value theorem which contains 3 proofs and effectively nothing "my older brother" could read just never said Encyclopedia to me. Also, User:Silly rabbit retired around that time I decided I needed a wikibreak to deal with my greif (he had mentored me into wikipedia when I first started editing Hilbert Transform).

When I came back, I had this crazy idea that proofs belonged in books, and have since been active at Wikibooks. Many people here seem familiar with wikibooks, because we do get the occasional transwiki. But the fact is that, as far as mathematics goes, wikibooks is starved of editors. Maybe this is true across all of the subjects, but math seems especially hard hit. After reading a conversation at the village pump, I thought maybe it would be good to start a project specific discussion about ways to encourage cross wikimedia project collaborations. We do really well here getting very good articles, Is it possible to use that success to seed the sister projects? How do we encourage collaboration? I have often restrained from adding links to wikibooks the math there is frequently is such bad shape, but I am a loss at what else to do to let people know we exist. Thenub314 (talk) 19:43, 11 May 2010 (UTC)


 * I think it would be nice if some of our activity could be more focused on the most important material for our customers audience. This should certainly include better development of high-visibility articles, but it could also include the creation of books or scripts. The German Wikiversity shows what is possible :
 * Two different two-week preparatory courses for university maths.
 * An almost complete two-semester course on Linear Algebra.
 * An apparently complete one-semester Introduction to Algebra.
 * An apparently complete one-semester course on Algebraic Curves.
 * An apparently complete three-semester course on Real Analysis.
 * An apparently complete one-semester course related to Mathematical Finance.
 * An apparently complete one-semester course on Number Theory.
 * Most of this material was created by just two editors. (On Wikiversity there is usually one responsible editor for each course.) Hans Adler 18:01, 12 May 2010 (UTC)


 * Eek! The word "customers" really rubs me the wrong way. Arcfrk (talk) 21:53, 12 May 2010 (UTC)
 * Better now? Hans Adler 00:07, 14 May 2010 (UTC)


 * I couldn't agree with you more. That is certainly an example to live up to! I have recently finished converting a Linear Algebra text from LaTeX into a format readable on wikibooks. In nominating the book to be a featured book, it was suggested to me that the individual modules should link to wikipedia.  And I have added a few random reciprocal links back to the book.  Maybe we can have a cross-wiki collaboration, and see if we can a) improve some articles here on important linear algebra topics b) improve the book c) improve the wikiversity course... etc. Sort of a "Linear Algebra Month" where we try all try do donate a little of our editorial effort to our sisters.  In hopes that our readers get a really first rate coverage everywhere they look.  I would certainly be happy to do some editing at wikiversity and here (does wikitionary cover math jargon?  I am not even well versed in what each of the sister projects do.)
 * At least improved coverage. And maybe Linear Algebra is not the place to start, I only mention it because there is now a book that exists.
 * I think by focusing on "core subjects" does a lot for speaking to the credibility and usefulness of all of these projects. Thenub314 (talk) 18:38, 12 May 2010 (UTC)

I'm late but anyway. I'm still quite surprised that Wikibooks didn't really take off (you can't honestly say the project is working right now.) This is surprising given how expensive textbooks are and there is clearly a demand for textbooks in electric formats. (I don't buy the argument that people prefer dead-tree; if so, why is Wikipedia so popular?) I think one issue is that Wikibooks is suffering from negative network effects; i.e., poor contents attract few contributors which result in stagnation in content creation, a negative cycle. This happens to many user-generated content projects (e.g, Citizendium), and the major cause of this is WIkipedia. Any such projects must just have to compete with Wikipedia, and of course, they don't win. Ironically, Wikibooks is no exception; it has to compete with its bigger brother for contributors. Simply, Wikipedia has "good enough" coverage in math; for example, it already contains a lot of proofs, much more than any textbooks in Wikibooks.

Maybe the mistake we made was to separate textbook creation from wikipedia. At least, in math, maybe textbooks are not dissimilar enough from encyclopedias. Why should an online encyclopedia (as opposed to print one) be forbidden from containing proofs, given unlimited disk space? (PlanetMath does contain proofs.) A student needs exercises or gentile guidance when learning new stuff for sure. But isn't providing that the function of Wikiversity? (Gee, I sound like thinking of customers.) Ideally, Wikibooks is a repository of proofs and other materials like formulae; but why can that role be filled by Wikipedia?

I know this won't happen, but personally, I believe merging Wikibooks and Wikipedia is very good idea. It benefits both. Wikibooks would get huge boost in content creation, and Wikipedia finds a place to put contents that may be beyond the scope of the "paper" encyclopedia. But most important, Wikibooks and Wikipedia would no longer have to compete with each other. -- Taku (talk) 22:54, 15 May 2010 (UTC)


 * I think any kind of "merge" between Wikibooks and Wikipedia is a bad idea; they serve different purposes. Anyways, here's my two cents: The reason I work on Wikipedia is b/c I *use* Wikipedia. (And I don't often use Wikibooks.) I agree with the comments above on this point, there's a "negative cycle": little content -> few readers -> few editors -> little content -> ....  I think Wikibooks will eventually reach a "critical mass" and begin to be more heavily used. Wikipedia articles also have an advantage in that they are targeted to one topic.  Writing a book (or chapter in a book) require more forethought, and are less amenable to editors who often begin their work saying something like "I've got 30 minutes free, I think I'll write something." Justin W Smith talk/stalk 05:02, 16 May 2010 (UTC)


 * Actually WP content on mathematics is very different from textbook standard content. As far as mathematics is concerned, encyclopedia articles are much easier to write than textbook chapters. And they are much worse to learn from, as far as a detailed grasp of the subject goes. (And that is true of other Internet materials on mathematics, too, sadly.) My comment about Wikibooks would be that typical mathematics textbooks arise from sets of lecture notes that are then written up more fully. There are some obvious conclusions to be drawn, about motivations and starting points. Charles Matthews (talk) 10:49, 16 May 2010 (UTC)
 * "Writing a book (or chapter in a book) require more forethought" and more effort and a lot more patience... =S
 * But I don't think on Wikibooks as a simple "repository of proofs and other materials like formulae": there is a lot of subjects which can benefit from a really carefully explanation in mathematics, and at Wikipedia there is no space for this (when we are explaining something, it is usually necessary to repeat the same thing in different words, maybe more than two times...). In a wikibook we can use all the didactics we could think of! And we can have two (or more) books on the same topic, but with different approaches (e.g. one explaining the concepts from abstract to particular while in the other everything comes from examples that are then generalized)
 * I agree with Charles. My contributions at pt.Wikibooks in math are mainly based on lecture notes... Helder (talk) 21:20, 16 May 2010 (UTC)

I agree that writing a traditional textbook is much more a daunting task than adding a piece of information to WP. But books in Wikibooks don't have to be typical textbooks; in fact, there is a book that is problem set or there is a book that provides solutions to widely used textbooks (e.g., Rudin). In theory, editing them should be as easy as editing WP. Charles Matthews mentioned lecture notes. I believe lecture notes belong to Wikiversity. Given the dynamical nature of wiki, it definitely makes sense to run courses in a parallel to development of course notes. (And our free license allows to create new sets of notes from old sets; mash-up, as the young people say.) By the way, today, students do use Internet a lot to do math homeworks; there are many sites that show you how to do typical Calculus problems. They are not good for in-depth grasp of subjects? Yes. But our mission is more modest than taking over the world (right?). I believe there is a gap in our offering; that is, Wikipedia and Wikbooks (and Wikiversity too ) don't provide this type of resources. (Gee, I sound speaking of "customers" again.) This gap arises in part because both Wikibooks don't want a calculus cookbook or a repository of proofs, say. -- Taku (talk) 21:53, 16 May 2010 (UTC)


 * I find the above discussion very interesting. There are lots of reasons why wikibooks is struggling, and for mathematics lack of useful content is certainly the main one, this is closely related to the lack of active editors.  These problems are not unique to wikibooks either, my brief glances at en.wikiversity show that for mathematics the same problems appear to exist.  I suppose I am hoping that we could pick one topic, much like the collaboration of the month, and make the goal "let's improve the coverage of this subject across wikimedia".  We might start small with a more specific project then I suggested before.  Subjects like Solids of Revolution come to mind. We could list of a few articles from each site that could be improved on this subject.  Examples from wikipedia might include: Solid of revolution, Pappus's centroid theorem.  Wikibooks: Calculus/Volume of solids of revolution, the syllabus of v:Topic:Calculus (since I feel most calculus courses touch upon this subject in some way. But the wikiversity course doesn't touch it.)  Commons: A animated image of first coarse disks, followed by successively thinner disks approaching the volume of the say a sphere.  Would anyone be opposed to creating a small box to add to the project page near the collaboration of the month box?


 * For what it is worth I am not that keen on a merging the projects either. But I do find Books (or for a mathematics specific example Book:College Mathematics- Algebra) as something of a duplication of effort.  But... "what can you do?"  It seems like the lines between the projects get a bit blurry if you look too closely. For example I feel that the Reference desk, which is really about learning and understanding should really be a part of wikiversity, but this is not feasible for two reasons.  First, wikiversity probably doesn't have the editor community to support it.  Secondly it has a lot of momentum, lots of people do good work there answering peoples questions.  People know to turn up there with questions and it would turn off editors to suddenly moved it.  I suppose it falls under it seems it should fall under the "if it ain't broke..." philosophy, even if it is in a less then optimal spot. But enough of ranting about separate topics. Thenub314 (talk) 13:56, 19 May 2010 (UTC)

Slightly off-topic
Wikipedia_talk:Bot_policy. Since this project uses a number of bots, I thought I should let you know. Pcap ping  08:34, 18 May 2010 (UTC)

Numerology and limitation of scope.
Recently some articles were brought to our attention because they were needing sources, one of them was about a numerologist. Now I don't think that there's any doubt the biography of a numerologist should not fall into the scope of this Wikiproject. So I was thinking that as a precautionary measure - there should be some sort of statement about what this project and all the mathematical categories are not for. I was thinking that it should cover these things: I don't think much of this has actually come up or caused a problem, but I think it should be made clear before it does. As I said, a precaution. If I were to go ahead with writing such a thing - should it be an official part of the project, or simply a wikipedia essay? --Paul Carpenter (talk) 12:54, 19 May 2010 (UTC)
 * 1) Numerology and related things that just aren't mathematics. Would be better suited to WikiProjects such as Sprituality or Pseudoscience.
 * 2) Individual numbers, simply because there is  Wikiproject dedicated to articles about numbers.
 * 3) Statistical data (as opposed to the study of statistics itself), more or less for the same reason as individual numbers not falling within our scope.


 * If we need such a statement, it should be part of this project, since it would be describing an internal matter (our intended scope) rather than an external one. But I am not (yet) certain that we need a clarification about this. One issue is that the type of people who think that this project is related to numerology are unlikely to actually read a long description of our scope before bringing an article here. So I don't know that a formal statement of scope would actually solve the perceived issue. &mdash; Carl (CBM · talk) 13:04, 19 May 2010 (UTC)
 * I was thinking of it as an external issue - since it applies the categories and portals as well as the project. Also, in terms of application - like a lot of essays, it can be referred to easily in discussions and edit summaries e.g. "removed mathematics category per [some essay]".
 * If it's not strictly needed here then I'll leave it as a personal essay. Paul Carpenter (talk) 14:16, 19 May 2010 (UTC)
 * I'm not sure how the article got added to the list in the first place. It's not in any math related categories, it's not in List of mathematics articles and it doesn't have a maths rating tag. We might do well in general to have a better defined scope for this project, but I don't think that was the issue in this case.--RDBury (talk) 19:33, 19 May 2010 (UTC)
 * It was a call for expert attention, actually. Perhaps just by saying it wasn't anything to do with us, we successfully answered that. --Paul Carpenter (talk) 21:56, 19 May 2010 (UTC)


 * This strikes me as a solution in search of a problem. There is no realistic prospect that activity on articles about numerology and such is going to grow to levels that will be a serious distraction to the project.  If an occasional one shows up in one of our lists, really, so what?
 * On the other hand, we do occasionally have issues with editors who have restrictive notions of what constitutes mathematics (such as that mathematics is defined by a technique, such as formal proof) inserting those ideas in an insufficiently qualified form into articles. I would be much more attentive about not giving any encouragement to that sort of effort.  --Trovatore (talk) 20:09, 19 May 2010 (UTC)
 * Perhaps, it's just not something I'd like to see happen into the future. Like I said, I'm leaving it as a personal essay, I will however take all of that into consideration as I add to it - I think there is a lot that could be said on the topic of what constitutes mathematics in the context of Wikipedia. --Paul Carpenter (talk) 21:56, 19 May 2010 (UTC)

Unreferenced Biographies of Living Persons
The WikiProject Unreferenced Biographies of Living Persons (UBLPs) aims to reduce the number of unreferenced biographical articles to under 30,000 by June 1, primarily by enabling WikiProjects to easily identify UBLP articles in their project's scope. There were over 52,000 unreferenced BLPs in January 2010 and this has been reduced to 32,665 as of May 16. A bot is now running daily to compile a list of all articles that are in both Category:All unreferenced BLPs and have been tagged by a WikiProject. Note that the bot does NOT place unreferenced tags or assign articles to projects - this has been done by others previously - it just compiles a list.

Your Project's list will be located at WikiProject Mathematics/Unreferenced BLPs. The list of all other WikiProject UBLPs can be found at WikiProject Unreferenced Biographies of Living Persons/WikiProjects. Doing a recursive scan of Category:WikiProject Mathematics articles (which is a different method than what the bot uses) I've found 5 articles:


 * Glynis McCants
 * Luke Pebody
 * Mike Lesser
 * Olivier Ramaré
 * William Lawvere

Your assistance in reviewing and referencing these articles is greatly appreciated. If you have any questions, please don't hestitate to ask either at WT:URBLP or at my talk page. Thanks,The-Pope (talk) 11:54, 18 May 2010 (UTC)


 * I removed the tag from Mike Lesser, which does have references. Of the remaining ones, I think properly sourcing William Lawvere should be a priority.  The other three (Glynis McCants, Luke Pebody, and Olivier Ramaré) seem to be on the borderline of notability.   Sławomir Biały  (talk) 12:13, 18 May 2010 (UTC)


 * I don't see any reason why Glynis McCants and Olivier Ramaré should be considered notable, there is however extensive discussion on the talk page for Luke Pebody about his notability, so I have added speedy deletion templates on the McCants an Ramaré pages and am leaving Pebody for now. Aside from the need for sourcing there is also a need for general improvements to both the articles on Mike Lesser and William Lawvere articles. --Paul Carpenter (talk) 12:52, 18 May 2010 (UTC)


 * The Pebody discussion was heated in 2003. I think we now take a different view of "famous for just one thing". PROD, or merge into necklace problem. Charles Matthews (talk) 13:51, 18 May 2010 (UTC)


 * (ec) Yikes, Glynis McCants is a "numerologist" on Oprah. The speedy deletion was removed by someone else though.  Perhaps removing association with WikiProject Mathematics would suffice?
 * But shouldn't Olivier Ramaré be notable? He has published approximately 42 articles (rough count from 2 sections at "reprints" link from his webpage.  The wikipedia article asserts he completed a proof of a simply expressed theorem (isn't that itself unusual? :) ).  I removed the speedy deletion.  I am not all up to speed on what makes one professor notable and others not, but couldn't this be developed rather than escalated to AFD?  Unfortuneately i can't do that development though. --doncram (talk) 13:56, 18 May 2010 (UTC)
 * I have removed our association with Glynis McCants - though the problem of it being poorly sourced and only borderline notable still remains, it is not (as participants in this project) our problem.
 * Regarding what makes an academic notable, see the professor test.
 * Paul Carpenter (talk) 15:07, 18 May 2010 (UTC)

The article William Lawvere has several external links that qualify as "sources" for the purposes of determining if a BLP article is "unsourced". For example, the extensive BICM interview. Of course detailed sourcing is nice, but that article clearly not "unsourced". &mdash; Carl (CBM · talk) 14:11, 18 May 2010 (UTC)
 * The lack of inline citations makes it difficult to verify any of the sources, but you're right in that it's not unsourced. That leaves Olivier Ramaré and we are done for now. Paul Carpenter (talk) 09:17, 21 May 2010 (UTC)

Pythagorean theorem
Some weird things are going on at Pythagorean theorem, Talk and here. People doubting that the theorem wouldn't be valid in R^n and such. Haven't got much time. Just added this ref to a simple proof. Someone might take a close look at the recent edits though... DVdm (talk) 12:21, 18 May 2010 (UTC)
 * I find it hard to apply Hanlon's razor in this case and not simply assume that this is a transparent WP:POINT violation in order to "prove" a problem with our processes. Hans Adler 12:38, 18 May 2010 (UTC)
 * Erm, Hans, I must say that I have no idea what you mean. What is "this ... violation"'? My little suggestion here, or the things going on over there? DVdm (talk) 12:52, 18 May 2010 (UTC)
 * I meant some of the things going on over there, but I guess Carl is right. Hans Adler 13:09, 18 May 2010 (UTC)
 * I think that we may both have been right about different things. It would be good for several people to keep the page on their watchlist for a while. &mdash; Carl (CBM · talk) 23:59, 18 May 2010 (UTC)


 * Just to be clear: the issue is not with the "Pythagorean theorem" per se. Because a triangle is by definition contained in a plane, and every plane is isometric to the canonical xy-plane, the 2D form of the actual Pythagorean theorem is the only one that requires proof. What seems to be at issue on the talk page are various identities involving cross products that are sometimes labeled "Pythagorean". Of course we don't expect cross products to be defined in arbitrary n-dimensional spaces. Since that is already a side topic in the article on the Pythagorean theorem, just get the statements right and move on (which looks like what may be happening on the talk page). &mdash; Carl (CBM · talk) 13:01, 18 May 2010 (UTC)

Note that two of the involved editors are on general probation. See Arbitration/Requests/Case/Speed_of_light. TimothyRias (talk) 13:32, 18 May 2010 (UTC)


 * Yes, look here, we are "WP crazies" now. DVdm (talk) 15:47, 20 May 2010 (UTC)


 * The article itself seems OK, though. I'd let the comment on a user talk page pass as not worth much of a response. &mdash; Carl (CBM · talk) 16:03, 20 May 2010 (UTC)


 * Indeed. Too bad it's so hard to track the changes. With brews making 10 edits per minute on the average, one has to wait until he's gone to sleep before one can get an idea of what has happened, let alone make a few changes here and there. When he's around, it's edit conflicts all over the place. Sigh. DVdm (talk) 16:29, 20 May 2010 (UTC)


 * And David Tombe: "Clearly Pythagoras's theorem is a 3D theorem. It is a theorem about a 2D triangle in a 3D space.". Should people like that be allowed to touch articles? DVdm (talk) 17:19, 20 May 2010 (UTC)

TOCright
Today, I removed the TOCright template from the few math articles that used it (about 25 out of 24,000 articles). This template has the effect of floating the table of contents to the right side of the page. In a few cases, I replaced it with the toclimit template, to hide excessive subsections. Otherwise, I just removed it. I know of no argument why floating the table of contents to the right would be desirable in a math article, and all but a handful of our articles have never used it.

The template was reinstated on material derivative. Could someone else look into that? I don't see any compelling reason for using the template there. &mdash; Carl (CBM · talk) 18:10, 21 May 2010 (UTC)


 * It may improve readability (if moved down a line, into the #Names section). At least, on my screen, the TOC and the list of names don't interfere with each other.  — Arthur Rubin  (talk) 18:25, 21 May 2010 (UTC)


 * It appears that this template should only be used with dab pages but there is very little in the template doc about in which pages it should be used. Perhaps this is really more an issue for Village pump since I doubt any project wants TOC's to appear in random locations in their articles.--RDBury (talk) 18:31, 21 May 2010 (UTC)


 * I agree there is very little guidance about when TOCright is actually warranted. I have left it alone on dab pages and similar pages, because I know it's often used on those (but I also don't know why). I can start a village pump thread later, if nobody else does. &mdash; Carl (CBM · talk) 19:55, 21 May 2010 (UTC)

hyperbolic translations
It Would Be Nice If Hyperboloid model, Beltrami–Klein model, Poincaré half-plane model and Poincaré disk model gave explicit formulas to convert coordinates among them. (Beltrami–Klein model does give conversions to and from the conformal disk.) —Tamfang (talk) 17:49, 20 May 2010 (UTC)


 * Since the hyperboloid model is the most natural model, I think each of the others should explain how it is related to that one. Actually, the Klein model and the Poincare disk model already do this. The article on the Klein model says "The Beltrami–Klein model is obtained from the hyperboloid model by rescaling all vectors so that the timelike component is 1, that is, by projecting the hyperboloid embedding through the origin onto the plane x0 = 1.". The article on the Poincare disk model says "If we have a point [t, x1, ..., xn] on the upper sheet of the hyperboloid of the hyperboloid model, thereby defining a point in the hyperboloid model, we may project it onto the hypersurface t = 0 by intersecting it with a line drawn through [−1, 0, ..., 0]. The result is the corresponding point of the Poincaré disk model.". So the only one which is not already connected is the Poincare half-plane model. JRSpriggs (talk) 02:11, 21 May 2010 (UTC)


 * Converting from Poincaré to hyperboloid is not quite trivial, though: I've just tried twice to derive a formula and got two different wrong answers! —Tamfang (talk) 04:39, 22 May 2010 (UTC)


 * I assume you are talking about the Poincare disk model.
 * The point $$\langle t, \vec{x} \rangle \,$$ on the upper sheet of the hyperboloid is mapped to the point $$ \vec{y} = \frac{\vec{x}}{1+t} \,$$ in the Poincare disk. So $$ \vec{x} = \vec{y} (1+t) \,.$$ A point on the upper sheet must satisfy $$1 = t^2 - \vec{x} \cdot \vec{x} = t^2 - y^2 (1+t)^2 \,.$$ Thus $$ 0 = (1 - y^2) t^2 + (-2 y^2) t + (-1 - y^2) \,.$$ Solving the quadratic equation gives $$ t = \frac{2 y^2 + \sqrt{4 y^4 - 4 (-1 + y^4)}}{2 (1 - y^2)} = \frac{1 + y^2}{1 - y^2} \,.$$ Thus $$ \vec{x} = \frac{2 \vec{y}}{1 - y^2} \,.$$ Is that OK? JRSpriggs (talk) 00:55, 23 May 2010 (UTC)

Math in Moscow
Math in Moscow has been prodded, i.e. deletion of the article will happen if no one objects for five days. What Do We Think? Michael Hardy (talk) 03:22, 21 May 2010 (UTC)


 * Zpconn 20:09, 2 May 2010 (UTC) wrote (Talk:Math in Moscow):“Since the Budapest Semesters in Mathematics program has its own page, I felt Math in Moscow should have its own page as well.”
 * The both noted articles (Math in Moscow and Budapest Semesters in Mathematics) are very strange and may be improved or removed. For example, “The IUM is located in a building in the very heart of Moscow. The address is 11 Bol. Vlasievskii per., a small quiet street near the historic Arbat and within walking distance of the Kremlin, the Bolshoi, the Rumyantsev library, the Pushkin Western Art Museum, and the cathedral of Christ the Savior .” (The article should not be Moscow guide)--Tim32 (talk) 07:51, 21 May 2010 (UTC)


 * I think in both cases (Moscow and Budapest) the articles are very likely borderline notable, but it would be more reasonable to have articles about the respective mathematics departments and put the information there. Hans Adler 11:08, 21 May 2010 (UTC)

I un-prodded it since it seems this will bear discussion.

So: expand, or merge into another article, or delete, or what? Michael Hardy (talk) 21:53, 22 May 2010 (UTC)


 * Certainly notable, even if not easy to source. Arcfrk (talk) 00:39, 23 May 2010 (UTC)

Cartan's lemma
I recently moved Cartan's lemma to Cartan's lemma (potential theory). There are enough things named "Cartan's lemma" that I feel explicit disambiguation is necessary, even if we don't currently have articles about the others. Any thoughts on whether a redirect of Cartan's lemma > Cartan's theorem would at this point be appropriate? Sławomir Biały (talk) 21:52, 22 May 2010 (UTC)


 * I also should say that the new article Cartan's lemma (potential theory) is insufficiently developed that one can reasonably discern that it is about potential theory at all. It's not even clear to me that the result is stated properly.  Sławomir Biały  (talk) 21:56, 22 May 2010 (UTC)


 * I have completely rewritten it from the cited source. It appears that the article had attached the name of Cartan to the wrong theorem!  Sławomir Biały  (talk) 22:06, 22 May 2010 (UTC)


 * Was it at least the right Cartan? Arcfrk (talk) 00:42, 23 May 2010 (UTC)


 * Yes :) Sławomir Biały  (talk) 00:47, 23 May 2010 (UTC)

Invariant subspaces
I am not convinced that we need the newly created Category:Invariant subspaces. What do you all think? Arcfrk (talk) 00:49, 23 May 2010 (UTC)


 * Update: in the process of populating this category, Kiefer.Wolfowitz has added a large block of references to several articles (I believe, this qualifies as WP:REFSPAM). I have reverted the most egregious instances (in Perron–Frobenius theorem, Invariant subspace, and Burnside's lemma), but I really question their value in other cases as well. Arcfrk (talk) 15:01, 24 May 2010 (UTC)


 * The Perron-Frobenius theorem is discussed within the books on invariant subspaces by Aliprantis and Burkinshaw and by Radjavi and Rosenthal (simultaneous triangularization); it is also discussed by Lybuich (Banach representation of groups) and by various authors following de Pagter's use of Lomonosov's invariant subspace theorem to prove that compact positive operators have a postive spectral radius. Given this literature, Arcfrk's comment "category spam" was as impolite as Arkfrk's deletion was unwarranted. Kiefer.Wolfowitz (talk) 01:09, 23 May 2010 (UTC)
 * "Category spam" is an objective reason for deletion removal, there is nothing personally offensive about it. Do you understand the purpose of the category system in the first place? Also, as Kiefer.Wolfowitz has started an edit revert war referring to this thread to justify his edits, an extra pair of eyes at Perron–Frobenius theorem will be greatly appreciated. Arcfrk (talk) 22:13, 23 May 2010 (UTC)


 * Before casting stones .... Arcfrk first delete the membership of the article Perron-Frobenius in the category invariant subspaces with only the comment "category spam". So far, Arcfrk and the other editor have failed to reply to the reliable authorities (Aliprantis and Burkinshaw; Radjavi and Rosenthal), whose standard books devote at least a chapter to Perron Frobenius theory (c.f., Lyubich's books). It is not edit-warring to revert an un-motivated POV (and undue-weight) edit whose only explanation was a sneer. Now, Arcfrk cries about being reverted and cautions me not to edit war, when his pov editiing is contrary to the reliable sources, and he is guilty of edit-warring. The only comment pertinent to PF-Invariant subspace membership was that said link is trivial---which is POV contrary to the books mentioned, which have never been discussed by the 2 other editors. (2 editors on a Sunday night is hardly the consensus of the WP:Math project!) On the other hand, Arcfrk has criticized the earlier version of the category on invariant subspaces, but that is another matter: It would be edit warring to revert a nullification of the category, in contrast. Thanks Kiefer.Wolfowitz (talk) 22:34, 23 May 2010 (UTC)


 * I would very much appreciate if you leave my name out of your incoherent rants, thank you very much. Here is a relevant policy: WP:AGF. I have reverted the inclusion of irrelevant categories (and again). This has nothing to do either with either WP:POV or WP:UNDUE (no content was added or removed). The fact remains that the burden is on you to demonstrate the relevance of all these additions. The primary purpose of references is to verify the content of the article. Most things in mathematics are related to each other in one way or another. That does not, however, mean that every book on matrix theory, operator theory, and who knows what else ( Coxeter groups ? Seriously?) that shows up on a google or MathSciNet search belongs to the reference list of this particular article. Similar remarks apply to categories. Arcfrk (talk) 03:01, 24 May 2010 (UTC)


 * Humphreyes's Reflection Groups and Coxeter Groups discusses the Perron-Frobenius theory in Section 2.6. Please stop questioning my good faith and please stop personal attacks ("incoherent rants"). Please review your mistaken previous statements about the irrelevance of PF and invariant subspaces (apart from triviality); I'm pleased that you are moderating your statement now. However, you still have failed to address the reliable sources (Aliprantis, Burkinshaw, Rajdavi, Rosenthal, Lyuvich) linking the PF theory and invariant subspaces: These reliable sources should outweigh your POV. Thanks, Kiefer.Wolfowitz (talk) 15:58, 24 May 2010 (UTC)
 * Given that this discussion has been sent to CfD, please put your further arguments there and there only. It is not up to this WikiProject to rule on the existence or renaming of categories. It seems that there are mathematicians on both sides of this discussion, so that it would all round be better to treat them all as colleagues. If you feel that they should do the same for you, then I of course agree. Charles Matthews (talk) 16:39, 24 May 2010 (UTC)


 * I take your point, Charles. The references are a related issue that I felt was relevant for the math project (but not for the CfD discussion). Perhaps, I could have mentioned them separately. Arcfrk (talk) 07:42, 26 May 2010 (UTC)


 * The category looks like a disjointed jumble to me. I'd vote to delete it. Ozob (talk) 02:24, 23 May 2010 (UTC)
 * You two seem to edit mainly in algebra, rather than modern analysis and operator theory. Could you request an opinion from an analyst?
 * See Henry Helson's book on Invariant subspaces to read about the Beurling factorization theorem (Hardy spaces), which is an abstract version of the Wold decomposition; this is also discussed in Young's book on Hilbert Spaces. Most of the topics are covered in Beauzamy and Lyubich's books. Kiefer.Wolfowitz (talk) 02:53, 23 May 2010 (UTC)
 * I don't see what relevance my area of expertise has to do with this. I didn't comment on the articles in the category but on the category itself. Furthermore, Burnside's lemma, invariant subspace, linear subspace, and simple module are all algebra, and together they make up more than half the category. (I'll grant you that there's a brief mention of Hilbert and Banach spaces in invariant subspace, but it's quite short, and the article is clearly weighted towards algebra.)
 * My central claim is still that the category is disjointed and jumbled. I would still vote delete. Ozob (talk) 03:06, 23 May 2010 (UTC)
 * Journal Title - Israel Journal of Mathematics

Article Title - An extension of Burnside’s Theorem to infinite-dimensional spaces Volume - Volume 75 Issue - 2 First Page - 329 Last Page - 339 Issue Cover Date - 1991-10-01 Author - V. Lomonosov DOI - 10.1007/BF02776031 Link - http://www.springerlink.com/content/C1Q77462X50P4170

Deletion discussion
I've nominated it for deletion. Please, cast your vote and explain the reasons here. Arcfrk (talk) 03:51, 23 May 2010 (UTC)

Requesting project help on Cheung-Marks theorem
This article is new and already up for deletion. Would someone from this project evaluate it for notability? Thanks.--Mike Cline (talk) 22:20, 23 May 2010 (UTC)

Perron–Frobenius theorem: help requested
The non-content part of that article is quickly becoming a dumping grounds for anything that might possibly be construed to be related to the topic. First it was loose addition of categories, followed by proliferation of references (continuing an earlier campaign by the same editor), and finally turned into bizarre personal attacks in this forum. I would be much obliged if some experienced editors can intervene. Arcfrk (talk) 02:21, 24 May 2010 (UTC)


 * Several other articles in the currently contested Category:Invariant subspaces suffer from the same problem: refspam. I've reverted some additions, cf the thread above. Arcfrk (talk) 15:06, 24 May 2010 (UTC)


 * Would you try to delete an article entitled "Perron-Frobenius theory", about generalizations of the finite square-matrix result, also? May I develop the material you deleted into a self-standing article? Kiefer.Wolfowitz (talk) 17:29, 24 May 2010 (UTC)


 * I would have no objections to an article systematically explaining generalizations of PF theorem. I have said as much on the PF theorem talk page. Obviously, it would need to make sense mathematically. Arcfrk (talk) 07:31, 26 May 2010 (UTC)

Knight's Tour FPC
See Featured picture candidates/Knight's Tour.--RDBury (talk) 20:24, 25 May 2010 (UTC)

C-K Theory
I removed some mathematics categories from C-K Theory because, although I can't really tell what the article is about, it does not look like mathematics. The categories were restored. I would appreciate any additional opinions on the categorization of this page. &mdash; Carl (CBM · talk) 21:17, 25 May 2010 (UTC)


 * The article looks like a bunch of pseudotechnical woo if you ask me. Unfortunately Wikipedia has a high tolerance for this sort of nonsense.   Sławomir Biały  (talk) 01:45, 26 May 2010 (UTC)


 * See also design methods, where there has been trouble in the past with proponents and ownership. I have now tagged C-K Theory for neutrality issues. Charles Matthews (talk) 07:41, 26 May 2010 (UTC)

Angle brackets
There is a discussion at Talk:Pythagorean theorem on the proper typesetting of angle brackets. At least one editor is advocating a blanket change in multiple articles to using less-than greater-than symbols (rather than the more proper &lang; &rang; or $$\langle,\rangle$$.) Please comment there. Sławomir Biały (talk) 09:57, 26 May 2010 (UTC)


 * The author was proposing to change just one section in one article (Pythagorean theorem). Note that the "more proper" &lang;, &rang; display as boxes on many (if not all?) systems with Internet Explorer. I tested it on 12 systems. None of them showed angle brackets. DVdm (talk) 10:13, 26 May 2010 (UTC)


 * Yes, he had written "article section 'Inner product space'", which I had read as "article 'Inner product space'". My mistake.   Sławomir Biały  (talk) 10:38, 26 May 2010 (UTC)

I was surprised this issue is not in WP:MOSMATH, if only to say that greater-than and less-than signs should be avoided. As always, the issue is always with fonts, not with browsers. But finding the right settings can sometimes be difficult. &mdash; Carl (CBM · talk) 11:34, 26 May 2010 (UTC)


 * The above & lang ; or < math \ langle in Sławomir Biały's post appear as boxes but the following appear ok on my browser: 〈 and 〉 Bethnim (talk) 11:45, 26 May 2010 (UTC)


 * We just had a discussion on this in, not that anything was decided really. For inner products I'd say avoid the issue by using a⋅b.--RDBury (talk) 15:05, 26 May 2010 (UTC)


 * But what for Bethnim is ok appears here (firefox/linux) as boxes for unicode 3008/3009, which are spacing characters for asian text, not mathematical symbols.--LutzL (talk) 15:26, 26 May 2010 (UTC)

MOSMATH
I have started a section at Wikipedia_talk:Manual_of_Style_(mathematics) to discuss this. I think the MOS should give some concrete guidance to avoid using less-than and greater-than signs, just as it has concrete guidance on using &amp;minus; instead of a hyphen or using &amp;times; instead of the letter "x". &mdash; Carl (CBM · talk) 12:46, 26 May 2010 (UTC)


 * Note, however, that due to massive drive-by robotic "typo fix" edits, many &amp;minus; etc commands are replaced by "equivalent" html characters, the problem with it, of course, being that many new or inexperienced editors, who oftentimes pick up style by example rather than by reading MOS, never see the proper way to typeset things. Arcfrk (talk) 03:35, 27 May 2010 (UTC)

Merge proposal for Hinge theorem to Law of sines
I'm not a mathematician, so I invite experts to participate in this discussion which is at Talk:Law of sines. Cheers. Rodhull andemu  20:22, 27 May 2010 (UTC)

"Holonomy" and "Holonomic"
...are two separate articles. Should they be? Even if they're about entirely different concepts (I haven't looked) shouldn't their names make more sense than that? Michael Hardy (talk) 15:57, 27 May 2010 (UTC)


 * Although ultimately related, the two notions are completely different. Separate articles are definitely appropriate.   Sławomir Biały  (talk) 21:08, 27 May 2010 (UTC)


 * Agree. Holonomy is a mathematical notion, "what happens when we return back". There is, for instance, holonomy pseudo-group of a foliation. And in the holonomic article it is spoken on the so-called holonomic systems in physics: those that do not have "velocity direction" restrictions. (For instance, while skiing with ice skates, one can go _only_ in the direction they point, so the possible velocities space does not coincide with all the tangent space to possible positions -- and this "system" is hence non-holonomic.) --Burivykh (talk) 02:01, 28 May 2010 (UTC)


 * In any case, the material in Holonomic should be split in separate articles since it has material about three or four unrelated subjects. In general, it's not good idea to have articles with adjectives as titles since it often leads to this sort of thing.--RDBury (talk) 19:09, 28 May 2010 (UTC)

STIX fonts v1.0 released
Greetings, old friends.

I ceased participating in Wikipedia, and WPM in particular, some time back, with a heavy heart. One reason, among many, was the total disinterest of the software developers in decent mathematical typography (read: no MathML nor incorporation of something like blahTeX).

That has not changed. But one long-awaited major milestone has been reached elsewhere, which has prompted me to post here, so that all the mathematicians and friends who follow these discussions can benefit.

Year after year the STIX Fonts project has posted notice after notice telling us that a complete set of fonts for mathematics was right around the corner. Never once has a projection date been met, nor closely approximated.

Today, the vaporware precipitates into a solid release. The website reads: STIX Fonts Version 1.0 Released The initial set of 23 OpenType fonts is now available for download

•  Full Download (2.6MB Zip file) •  License as Text File or PDF File •  Documentation (PDF file) •  Press Release

Additional documentation for this release is still being worked on and will be posted to this site as soon as possible.

Version 1.1, which will include fonts packaged for use with Microsoft Office applications, is scheduled for release by the end of 2010. Version 1.2, which will include Type 1 fonts for use with LaTeX, will follow in 2011.

This site was last updated on 28 May. The next update will occur mid-June.

Please, put these open licensed fonts to good use, here and everywhere.

(My glyph test page, apparently long forgotten by most editors here, may be of help.)

Best wishes. --KSmrqT 22:03, 28 May 2010 (UTC)


 * It's good to hear from you. I have been anxiously awaiting these as well. Like Duke Nukem Forever the development process for these started in 1997, so it was a race to see which could remain vaporware longer.


 * I installed the fonts just now, and almost every character on your glyph page displays for me. On a modern Linux system, installation usually just means copying the .otf files to ~/.fonts and restarting your web browser. Firefox (at least) automatically falls back on them for characters not in your default font. &mdash; Carl (CBM · talk) 23:15, 28 May 2010 (UTC)
 * Damn. Never thought I'd live to see this. Algebraist 23:09, 29 May 2010 (UTC)

Vanity page?
Darij Grinberg looks very dubious to me. It's unlikely that it passes any reasonable notability test. "References" are half-broken links to blogs. Prod or AfD, perhaps? Arcfrk (talk) 11:05, 23 May 2010 (UTC)
 * Definitely doesn't look notable. I'm not certain about Encyclopedia of Triangle Centers either, which seems to be the only given claim to notability. --Paul Carpenter (talk) 11:46, 23 May 2010 (UTC)
 * I think ETC should be considered similarly to OEIS in this respect: a very useful database for a specialized type of mathematical search, but being in there does not confer notability. We can use it as a source for articles on triangle center topics that have enough other sources to be notable, but not as evidence of notability for those topics. —David Eppstein (talk) 17:39, 23 May 2010 (UTC)
 * Yeah. I also don't see much evidence for notability as an academic. And since it's a WP:BLP the article really needs some sources. Justin W Smith talk/stalk 18:56, 23 May 2010 (UTC)

Prodded. Sławomir Biały (talk) 23:22, 23 May 2010 (UTC)
 * The article has been unprodded, on the basis that Grinberg won a medal at the International Mathematical Olympiad and that makes him notable (does it?) - AfD maybe? --Paul Carpenter (talk) 15:10, 30 May 2010 (UTC)
 * A gold medal seems to put you in the top 10% of participants, but I wouldn't reckon it is any serious evidence of notability. Charles Matthews (talk) 15:47, 30 May 2010 (UTC)
 * Looks like a candidate for AfD. An IMO gold medal does not automatically make the subject notable.  In fact, the article on four-time Putnam Fellow Arthur Rubin was not generally considered to be notable on the strength of his Putnam winnings alone (his Erdos number 1 ultimately seemed to tip the scales), and the Putnam is a much more exclusive award.  Sławomir Biały  (talk) 19:20, 30 May 2010 (UTC)

Now on AfD: See Articles for deletion/Darij Grinberg. Please direct your comments there. Sławomir Biały (talk) 19:31, 30 May 2010 (UTC)

Multiple move for coordinates
We currently have a collection of articles dealing with the various systems of coordinates. The names of these articles are are not consistent, for example Cylindrical coordinate system and Parabolic coordinates. The "X coordinates" format goes against WP naming conventions which say that a singular nouns are preferred (See SINGULAR). Therefore I propose that the articles whose names currently end with 'coordinates' be moved, so for example "Parabolic coordinates" would become "Parabolic coordinate system". There are quite a few articles like that and not all fall under WPMATH, so this would be done a few articles at a time. Are there any objections to such a move?--RDBury (talk) 20:24, 29 May 2010 (UTC)
 * I don't care either way, but I don't agree with your rationale. WP:SINGULAR mentions some common sense exceptions, introducing them with "exceptions include", andcoordinates seems to fit here quite nicely. I would agree with renaming to "coordinate system" under the rationale that that doesn't superficially look like a breach of WP:SINGULAR and is therefore more elegant. But I would hate this to be yet another precedent for ignoring common sense in the interpretation of policies. There are probably other cases of unavoidable plurals, with no elegant singular alternatives. Let us not contribute to their being renamed simply because they don't fall under the few exceptions that are mentioned explicitly. Hans Adler 20:45, 29 May 2010 (UTC)
 * I'm not trying to set a precedent for changing all articles with plurals in the titles. In this case the convention agrees with common sense since the articles are about coordinate systems rather than individual coordinates. A coordinate is just a variable unless in the context of a coordinate system.--RDBury (talk) 23:26, 29 May 2010 (UTC)
 * PS. A good example of what you're talking about is Simultaneous equations. I agree that it would make no sense to change it to "Simultaneous equation".--RDBury (talk) 23:31, 29 May 2010 (UTC)
 * On another hand, "System of simultaneous equations" is arguably more accurate. —Tamfang (talk) 00:46, 30 May 2010 (UTC)


 * Consistency is to be preferred, and I think the proposed direction is the correct one. The coordinates naming system is a bit informal. - 2/0 (cont.) 01:16, 30 May 2010 (UTC)
 * Simplicity is also to be preferred. "System of simultaneous equations" is less likely to be searched for or linked to than is "simultaneous equations". Michael Hardy (talk) 02:49, 30 May 2010 (UTC)
 * I agree. I don't see that adding the word "system" to the end of one of these title conveys any useful additional meaning. I think the shorter titles are better. K.I.S.S. —David Eppstein (talk) 16:32, 30 May 2010 (UTC)
 * "System" does convey meaning. Coordinates is just the plural of coordinate. In the plane, there are are multiple ways to select coordinate axes and choose a scale of measurement. The term "x-coordinate" does not have and meaning until these choice are made. Most of the time the choice is made implicitly and we say "coordinates" as a shorthand for "coordinate system", but article titles should be the correct names, not the everyday abbreviations. The most commonly read articles already use "system" in the titles, it's just there are a bunch of more obscure articles that don't.--RDBury (talk) 04:06, 31 May 2010 (UTC)