Wikipedia talk:WikiProject Mathematics/Archive/2007/Nov

Small reference font size

An editor has changed many articles to make the font size of the references smaller (example). This is a common thing to do on articles that have dozens of footnotes, and perhaps reasonable in that case. But many of the math articles only have a few references, so I don't see the need for the smaller font. The manual of style is silent on the issue of small vs. regular fonts in reference sections. What do others think? — Carl (CBM · talk) 17:38, 30 October 2007 (UTC)

Ditto. I find it a bit irritating but not enough so to do anything about it yet. Jmath666 18:39, 30 October 2007 (UTC)

I love the small font when there are lots of references. I don't mind it when there are few, but I never use the small font myself unless the article has maybe 8+ references. CRGreathouse (t | c) 19:16, 30 October 2007 (UTC)

I dislike the small font for the full references. I think it's OK, if there are lots of footnotes referring to the same article, but for the article reference itself I prefer the normal font. (E.g. as it is in Homotopy groups of spheres.)Jakob.scholbach 19:54, 30 October 2007 (UTC)

A part of the issue might be that the <ref> </ref> <references/> mechanism renders as footnotes, and footnotes indeed should be small. So some editors may not see the difference between scientific-style citations and footnotes. There is another citation style that renders as the usual [1] etc. I saw it somewhere on wikipedia but cannot find it right now. Jmath666 20:10, 30 October 2007 (UTC)

I guess I feel that either standard is fine but it ought to be uniform, or at least there should be a uniform quasi-standard for the number of references that trigger the small font. By "quasi-standard" I mean it doesn't have to be an exact number; if there are some articles with 25 references and the large font, and some others with 23 references and the small font, that's probably OK, but at least some rough idea of the fuzzy boundary should be present. --Trovatore 03:29, 31 October 2007 (UTC)

Yes, this is basically how I feel. Articles with more than ~20 references are best with the small font.

Jmath, if you come across that citation style I'd be interested. I too am annoyed with the conflation of footnotes used for explanation and references in a footnote style.

CRGreathouse (t | c) 13:26, 31 October 2007 (UTC)

If we could shrink the footnotes until they disappear completely, I'd be satisfied. References are first class citizens, and when I go to all the work to research them it is because I intend that readers should be able to read them, on an equal footing with sentences in the article. I revert "shrinking" on sight if it is done to an article I watch.

This is a disease that should be eradicated. We are not saving paper. We are not making it easier for readers to scan References, because scrolling works fine and tiny type does not. The implicit message is that no one is expected to consult a cited work; compare to a professional encyclopedia, where tiny type is not used for references at the end. Tiny type suits those who want a footnote after every period, which I emphatically reject for mathematics articles. --KSmrq^T 11:17, 31 October 2007 (UTC)

I agree that overfootnoting is not appropriate for mathematics articles. Articles with many footnotes, though (nonmath example: Great power, which over the last 8 months has had probably 25-50 references as it's edited) benefit greatly from the small font. CRGreathouse (t | c) 13:23, 31 October 2007 (UTC)

DYK

On November 1, 2007, Did you know? on the Wikipedia main page was updated with a fact from the article Bramble-Hilbert lemma. Jmath666 05:36, 2 November 2007 (UTC)

It's in this version. The nominator wrote "not that I understand the advanced math here".[1] It was picked by Blnguyen.[2] I wouldn't call the DYK text "hooky" as requested in Wikipedia:Did you know#Selections, but that may be hard for math articles. I suggested a less technical "hook" when primes in arithmetic progression got in DYK.[3] PrimeHunter 17:04, 2 November 2007 (UTC)

Thanks for the link. It may have gotten picked because the first sentence (which was partly quoted) makes sense even to those who "do not understand advanced math", say, beyond Calc I. Jmath666 21:10, 2 November 2007 (UTC)

STIX fonts

The STIX Fonts Project has released their fonts for beta testing. —Ruud 21:42, 2 November 2007 (UTC)

Chicken McNuggets problem

Didn't we deal with this before? Perhaps it needs more mathematical eyes on the problem. — Arthur Rubin | (talk) 21:11, 3 November 2007 (UTC)

Some edits to check

User:71.117.139.31 is making a bunch of changes to formulae with edit summaries like "fixed a variable", which I am reasonably sure are not correct. Can someone take a look? (this <math> stuff isn't my strong suit). --Stormie 23:21, 4 November 2007 (UTC)

They appear to be vandalism. I've undone them all and put a warning on his talk page. Thanks for the alert. —David Eppstein 23:34, 4 November 2007 (UTC)

ScienceWorld

ScienceWorld has been nominated for deletion at Wikipedia:Articles for deletion/ScienceWorld. At that page people should post their opinions---either Keep or Delete or Merge or Redirect or what-have-you.

My own view, and the reason why this page is where I'm posting this, is that the main reason to consider the topic notable is that this is a new effort by the same people who created MathWorld. When a new novel is to be published by an author who's won the Nobel Prize in literature, it can be considered notable, even before publication, because its author is so noteworthy. Michael Hardy 22:00, 31 October 2007 (UTC)

I concur. While notability is not always inherited, in some cases something is notable due (at least in part) to the involvement of some other notable entity. --Cheeser1 07:05, 5 November 2007 (UTC)

Houston, we have a mathematical problem...

When is the last time someone from here looked at the article Mathematical problem?  --Lambiam 04:07, 1 November 2007 (UTC)

Holy crap! That's all I'll say. VectorPosse 04:17, 1 November 2007 (UTC)

Little did I know, computing the decimal expansion of pi was one of the outstanding problems of mathematics! And here I thought it was finding secret encoded messages sent by Elvis from beyond the grave in the decimal expansion of pi. Anyhoo, I cut out some of the howlers from the article and marked it as a stub. I'm hoping one of you will be brave enough to start a proper fleshing-out of the article. I'll snipe from the sidelines. Cheers. Rybu —Preceding comment was added at 06:39, 1 November 2007 (UTC)

I hear the decimal expansion of π contains arbitrarily long arithmetic progressions. Jeepers. --Cheeser1 06:46, 1 November 2007 (UTC)

Yes, 0, 00, 000, ... (except that the proof is still missing).  --Lambiam 22:13, 5 November 2007 (UTC)

Notice of List articles

Page(s) related to this project have been created and/or added to one of the Wikipedia:Contents subpages (not by me).

• List of basic mathematics topics
• List of basic arithmetic topics
• List of basic algebra topics
• List of basic calculus topics
• List of basic discrete mathematics topics
• List of basic geometry topics
• List of basic trigonometry topics
• List of basic topics in logic
• List of basic statistics topics

This note is to let you know, so that experts in the field can expand them and check them for accuracy, and so that they can be added to any watchlists/tasklists, and have any appropriate project banners added, etc. Thanks. --Quiddity 19:25, 5 November 2007 (UTC)

Homotopy groups of spheres A-Class assessment

Regulars here will recall that about a month ago, I raised the idea of taking an article on advanced mathematics to FAC, and proposed Homotopy groups of spheres as such an article, on the grounds that it is both highly sophisticated, and generally appealing. Originally, my ambitions were merely to refine the article at the time. However, I have been delighted by the response: many editors have joined in an endeavour to produce a comprehensive article on advanced mathematics, and the article has trebled in size! Here, R.e.b. deserves a special mention for adding so much deep material. (I have done little more than copyediting.)

However, the huge improvement of this article has raised questions of accessibility, presentation and balance that are hard to judge from close-up. I also noticed that the A-Class assessment program has fallen rather quiet. So I have nominated this article for A-Class, primarily to get WikiProject wide input on the current article and stimulate some discussion. Please take a look at the article, and add comments to the review page. Thank you in advance to all, and thank you once again to those who responded with such enthusiasm to my previous post. Geometry guy 19:34, 5 November 2007 (UTC)

Math portal has run out of articles

Moved from WP:AN. Anyone want to look into this? — Carl (CBM · talk) 15:30, 6 November 2007 (UTC)

Hi. There seems to be a problem with the template of the article of the week (featured article) in the portal of Mathematics. The articles are not getting archived since June and i think that it gets updated automatically, often resulting in an empty article. There are some messages about the problem in the talk page, but we need the help of an administrator. —Preceding unsigned comment added by 189.180.224.85 (talk) 15:05, 6 November 2007 (UTC)

The pages have to be scheduled in advance, and it just seems that nobody's done that. Look at the following list:

• Portal:Mathematics/Featured article/2007 41
• Portal:Mathematics/Featured article/2007 42
• Portal:Mathematics/Featured article/2007 43
• Portal:Mathematics/Featured article/2007 44
• Portal:Mathematics/Featured article/2007 45
• Portal:Mathematics/Featured article/2007 46
• Portal:Mathematics/Featured article/2007 47

The red links show where nobody has created the featured article summary; it's now week 45 of 2007. So there's nothing wrong with the portal, except that nobody has updated it; try asking somewhere like Wikipedia talk:Wikiproject Mathematics to see if you can find someone to maintain the portal. --ais523 15:25, 6 November 2007 (UTC)

I used to keep these up to date but I've been neglecting the portal since last May. Thankfully some other editors have stepped up. It is a lot of work for one person to keep the portal up to date. More involvement from editors here would be helpful.

Actually, I'd like to come up with another system for the portal so that the above problem doesn't happen. It would be nice to just have a pool of featured article snippits and have the portal randomly select one each week. People could add more snippits as they see fit and we would have rotating content without the annoying periodic redlinks. I'll have to think of a way to do this. -- Fropuff 16:44, 6 November 2007 (UTC)

You might leave a message at Wikipedia:WikiProject Portals about that. I think one or more of the members of that group have probably done something similar already for other portals. John Carter 16:50, 6 November 2007 (UTC)

Fropuff, if the snippets are in some reasonable location it would not be hard to make a bot script that would update the portal once a week to pick a new snippet. I'd be glad to run that bot if others arrange the snippets. — Carl (CBM · talk) 17:21, 6 November 2007 (UTC)

I can think of two ways to do it. One would be to have the snippits at Portal:Mathematics/Featured article/n where n is some number. We would then have to have some page indicating the maximum n. Other way would be to put the snippits at Portal:Mathematics/Featured article/Article name and then have some page (such as Portal:Mathematics/Featured article list) that would list all the article names. The bot would then select a new one from the list every day/week/whatever (either by rotating through them or randomly selecting one). If we did this we should do something similiar for the featured pictures as well. -- Fropuff 17:41, 6 November 2007 (UTC)

We could just put the snippet pages into a category (Category:Mathematics portal articles of the week or something like that) and the bot would semi-randomly select a new article every week. While we're at it, we could separate the formatting of the "articles of the week" box from the snippet content. I should be able to look into this later this week. — Carl (CBM · talk) 17:56, 6 November 2007 (UTC)

What John Carter said. See Wikipedia:Portal/Instructions#Editing Archive for random portal component section for some (unclear?) instructions, and many examples of simple randomized content at the featured Portal:Cats, Portal:Environment, etc (click "Show new selections" to purge/refresh the page). Hope that helps. --Quiddity 18:07, 6 November 2007 (UTC)

Yes, it looks like if we do the numbered article thing we can use {{Random portal component}} to randomize the content. There would be no need to write a bot. From what I can tell this template will pseudorandomly select a new featured article on every page load (assuming the cache is purged). Maybe this is the easiest thing to do. -- Fropuff 18:44, 6 November 2007 (UTC)

That does seem to be quite simple to implement, and would require little ongoing maintenance. Let's do it. — Carl (CBM · talk) 19:19, 6 November 2007 (UTC)

I maintained the portal from May to September by recycling: 2007 portals 26-40 are essentially the list of 2006 portals. Sad to say, there aren't many other mathematics articles which are good enough to showcase. The proposed solution sounds fine: I just wanted to suggest that randomness is not essential - one can simply cycle. Geometry guy 19:37, 6 November 2007 (UTC)

What are the criteria for including an article? — Carl (CBM · talk) 19:46, 6 November 2007 (UTC)

Okay, I've updated the portal to use a slightly customized version of {{Random portal component}}. I've placed the content at

• Portal:Mathematics/Selected article/1
• Portal:Mathematics/Selected article/2
• Portal:Mathematics/Selected article/3

I'll try to move our whole slew of existing snippits to the new locations. I'll also try and update the archive to reflect the new format. And then do the same thing with the pictures. Let me know if you see any problems. -- Fropuff 20:07, 6 November 2007 (UTC)

improper integral

A confused person extensively rewrote the article titled improper integral. I reverted to the last version by Jitse Niesen. I left a message on the confused person's talk page explaining why at least some of what he wrote was erroneous. Possibly some assistance from some readers of this page in helping him out of his confusion will be needed later. Michael Hardy 16:33, 7 November 2007 (UTC)

Average

Could you please watch over average while keeping in mind that this is an introductory article to the topic? There's some good discussion and edits going on, but -- and I'm appealing to those of you who have kids trying to understand this topic -- could you please try to keep it simple in this article? Maybe encourage some of the discussion and text to move to more technical articles? Maybe try to simplify the article so that teens looking up "average" in Wikipedia won't be completely turned off? Illustrations would help a great deal. Shorter sentences and less jargon would help a lot. PLEASE help if you can! I'm not saying the information is bad or wrong, I'm just worried about it being in this general and basic article. --Foggy Morning 02:39, 8 November 2007 (UTC)

Casimir goes to Casimir

Casimir goes to Casimir is up for deletion. The AfD looks like it could use some input from those who know something about Casimir invariants. --Salix alba (talk) 08:16, 9 November 2007 (UTC)

AFD on a Kazakh mathematician; help?

There's an AFD on a Kazakh mathematician, Kareem Amin. It would be great to have some mathematical subject expertise on this? --Lquilter 18:46, 9 November 2007 (UTC)

My father (a statistician at Purdue) never heard of him, nor saw any indication he had written any papers. That may not be conclusive, but perhaps we have someone within research distance of the museum. — Arthur Rubin | (talk) 21:29, 9 November 2007 (UTC)

I just made the article on the museum - it's the major museum in kazakhstan and should have had an article before now, actually. (I was just there 2 years ago.) ... But I don't have any contacts there to look up his papers. --Lquilter 21:38, 9 November 2007 (UTC)

Satanic influences.....

Lists (PLURAL, dammit!!) of mathematics topics is a featured list.

List (singular!!) of mathematics topics is not.

After the featured list got moved to lists of mathematics topics (plural "lists"), someone changed Wikipedia:Featured lists so that it said list of mathematics topics (singular "list"), which was a redirect to the non-featured list of mathematics articles. Then someone saw that the page listed at Wikipedia:featured lists was not a featured list, and deleted it. The error stood for almost seven months. I've changed the singular title to a disambiguation page. Michael Hardy 02:25, 10 November 2007 (UTC)

Definable real number

I found this forum dialog: http://www.math.niu.edu/~rusin/known-math/98/definable

There are somes things that would be very useful in the article. But I don't know if this is usable as a source. I tried to contact David Madore, he didn't answered. As he is a teacher in the best French math faculty, I think it would be better that another teacher try to contact him. His adress is on the bottom of the page. Barraki 21:21, 8 November 2007 (UTC)

So I looked up the post above, and really I don't think there's much in there that's not already in the WP article (though I don't remember if the WP article discusses reals of L).

But I'm not sure everyone really understands the problem with the definable real number article. The problem is that editors not intimately familiar with the subject do Google Scholar or MathSciNet searches on the term "definable real number" and, seeing lots of hits, assume that there's some specific unique notion to which the term corresponds.

But there isn't. Take for example Madore's explanation:

a real number x is definable iff there is a predicate P(t) such that x is the only t such that P(t)

That's true, as far as it goes. But a predicate in what language, and with what interpretation? Different answers give you different notions of definable real. There simply is no well-defined notion of what it means for a real number to be "definable, full stop"; rather, there's a hierarchy of different sorts of definability using more and more powerful techniques.

So I never have known just what to do with this problematic article. I did a major rewrite on it quite some time ago to remove the implication that its subject matter was one clear thing; while my rewrite was quite frankly OR, it's less bad than it was before. What one would really like to do is make explicit the hierarchy of different sorts of definability to which I alluded. This is to some extent the subject matter of effective descriptive set theory. But effective descriptive set theory spends more time on definability of sets of reals than on definability of individual reals, and I don't know where to find a good source for the definability hierarchy on individual reals. --Trovatore 21:21, 10 November 2007 (UTC)

The relevant differences can be reduced to differences in the notion of "provability". Given some notion of provability, we can define definability of x, relative to that notion, as: the statement ∃!x·Px is provable. This can be considered with a more formal bend, but also with the rather informal notion of proof usually required for the elevation of a statement to theoremhood, where the people scrutinizing a proposed proof may suspect gaps to be unbridgeable, but will not lament that the language and interpretation are not precisely pinned down.  --Lambiam 03:22, 11 November 2007 (UTC)

Actually, no, provability is mostly a red herring in this context. What you need is a language plus semantics for that language. Now, certainly, if you like you can refine a notion of definability by requiring that it be provable, in some specified theory, that the defining formula has a unique real witness, and possibly this can even be useful once in a while. But in most cases it's just an extra complication -- you still need the semantics, and the formal theory doesn't give you that. --Trovatore 04:49, 11 November 2007 (UTC)

How does that not apply to a purported proof of, for example, the Poincaré conjecture? Don't you need a language plus semantics for the statement and the proof? Can you give an example of a disputed "definable number" for which the issue of the semantics of the proposed defining statement is at the heart of the dispute?  --Lambiam 06:53, 11 November 2007 (UTC)

Well, you don't really need a semantics for proofs. I mean you do in practice, for real-world proofs, but not in theory for formal derivations. By contrast, you don't need any proofs to define a real number -- you just need it to be true that x is the unique real such that P(x) holds; you don't need it to be provable. In fact it doesn't even really make sense to talk about it being provable; in general it takes infinitely much space to write down x, so how are you going to even get started on proving the claim? First you'd have to write down x, and you never finish with that.

I suspect that what you're doing here -- possibly unconsciously -- is conflating "definable real number" with "definition of a real number". Not the same thing at all. Which is why your request for an example also doesn't really make sense -- I can't really give any examples of definable real numbers, only of definitions of real numbers. However I can easily give you examples of a single definition for a real number that defines different real numbers depending on the semantics. Would that satisfy your challenge? --Trovatore 07:34, 11 November 2007 (UTC)

Look at the real and complex fields in the first order language of fields. In the reals, the definable (without parameters--otherwise it's a little silly) elements are precisely the algebraic reals. In the complex numbers, the definable elements are precisely the rational numbers, if I am not mistaken. (Everything else gets moved by an automorphism.) It's a semantic notion. It doesn't matter what theory that you consider the two as models of, and what is provable in the theories. They are both models of the theory of fields, for example, but the only elements whose existence can be proved in the theory of fields are the integers. You can't even prove the existence of 1/2 in the theory, since Z/2 is also a model of the theory. --Ramsey2006 07:27, 11 November 2007 (UTC)

{{refimprovesect}} at [[Probability]]

A user has strewn {{refimprovesect}} tags all over Probability.[4] What shall we do with those? Not only does this seem to go against the drift of the scientific citation guidelines, but also in general one would expect that in an article in summary style the references for the summarized material of the subtopics may be deferred to the main articles (as is also clearly suggested by Wikipedia:Summary style#Citations and external links). However, scanning the article for statements that are likely not covered by existing references, I noticed that the last section, Applications, has several unsourced challengeable statements in the first half, and then, starting with the weaselly proclamation that "It could be said that there is no such thing as probability", wanders off into an unsourced philosophical essay on Randomness.  --Lambiam 07:19, 10 November 2007 (UTC)

Salix alba has condensed the multiple tags down to one. Someone should contact the person who placed the improvement tags to see if there are genuine issues being challenged (in which case we should find refs) or just a general request for more sources (in which case we should remind them of {{sofixit}}). — Carl (CBM · talk) 12:28, 10 November 2007 (UTC)

What about the essay? Does it belong topic-wise, and if so, is it salvageable?  --Lambiam 02:57, 11 November 2007 (UTC)

I think the Probability and Probability theory articles have problems. Probability has a more philosophical bent focusing on the nature of probability, and Probability theory covers more advanced mathematical topics . What is missing is a basic high-school mathematics treatment, with the rules for p(A and B) etc. We discussed this before without a successful resolution. Maybe what is needed is a third article covering the mathematical basics. A radical solution would be to have a Probability and statistics article covering mathematical basics, move Probability to Probability (philosophy) and have Probability as a disambig/redirect.

I've removed one paragraph on there is no such thing as probability--Salix alba (talk) 08:10, 11 November 2007 (UTC)

Hats off to Salix alba for starting to move Probability in the right direction. I agree that both Probability and Probability theory are in a poor state. I gave my impression in June/July, and little has changed. It is embarrassing that Probability is only 15K. I would say that page renames are not needed: enlarging the Probability article with more high school math could well bring it into balance. However, any idea which improves the treatment of probability is most welcome! Geometry guy 21:02, 12 November 2007 (UTC)

Casimir goes to Casimir

If anyone knows anything about this topic, could they assist at Wikipedia:Articles for deletion/Casimir goes to Casimir? Michael Hardy 20:42, 11 November 2007 (UTC)

It was closed as a redirect. --Salix alba (talk) 13:49, 12 November 2007 (UTC)

Speedy deletion candidate.

Hi, i am no maths expert so i ask someone here if this article: 2^x makes any sense. Is it encyclopedic? Accurate? Thanks. Woodym555 23:21, 13 November 2007 (UTC)

It has been prodded instead. If expansion is possible, it would be welcome. Thanks. Woodym555 23:28, 13 November 2007 (UTC)

I replaced the prod with a redirect to Power of two. —David Eppstein 23:52, 13 November 2007 (UTC)

Good move. — xDanielx ^T/_C\^R 06:46, 14 November 2007 (UTC)

Wikipedia:Scientific peer review

This Scientific Peer Review project can hardly be called successful. While there have been a steady but small flow of articles submitted for review, the actual reviews have been either non-existent or in no real way different from those done through the standard Wikipedia:Peer review process. Some editors will recall that the project was started with an enthusiastic discussion about identifying expert reviewers through an elected board. Unfortunately as time went by, it became clear there was no consensus on whether we had a board, or on how it was to be set up or on what it was supposed to do. There was also a lack of consensus on what "sciences" we were covering, and on many other aspects. In the end we sort of lapsed into a minimal review process which has staggered on for about 18 months. I think it is time we decided what to do about the project. Unless people can come up with a new way forward and enthusiastically implement it, I think we have to declare that this project be no longer active in any sense and that editors should ask for review at WP:PR. I am posting this on the talk pages of the major Science WikiProjects. Please feel free to publicize it elsewhere. Please add you comments at Wikipedia talk:Scientific peer review#Is this inactive?. --Bduke 03:41, 14 November 2007 (UTC)

Help with some logic articles

I need help with Halting problem and Godel's incompleteness theorem. User:Likebox, an avowed fan of Archimedes Plutonium, is adding some content both literally and figuratively incorrect to these, and I don't see any way to resolve it by myself. — Carl (CBM · talk) 01:28, 2 November 2007 (UTC)

I'd almost given up on Halting problem. Perhaps I'll have a look at it tomorrow. Of course, he won't accept my ideas, either.... — Arthur Rubin | (talk) 01:31, 2 November 2007 (UTC)

I fixed halting problem this morning, but he reverted it. He is extremely confused about how to use terminology correctly, apparently favoring vague analogies instead of correct exposition. — Carl (CBM · talk) 01:49, 2 November 2007 (UTC)

While I agree with the idea of removing fluff and vague analogies from the article, you also removed the material that makes the article comprehensible to computer scientists. Is there some way of writing an article that's acceptable mathematically but written in such a way as to be understandable by programmers? For instance, there's no explanation of why a decision problem (which, to a programmer, can be explained as the desired behavior of a subroutine that has some input and a boolean valued output) has anything to do with sets of integers (a seemingly static mathematical object having nothing to do with computation). This is, by the way, a problem with both versions of the article; Likebox's version has separate sections with intuition and with rigor, but little connection between them. —David Eppstein 02:00, 2 November 2007 (UTC)

I didn't just remove it - I tried very hard to integrate it throughout the other text. Check the diff for my edit [5]. I don't mind at all the idea of having some intuition present, but not in the "he said/she said" way that claims there is a difference between computer science and recursion theory. I would be glad to work cooperatively to add more explanation throughout both articles as appropriate. — Carl (CBM · talk) 02:20, 2 November 2007 (UTC)

I totally agree that the "he said/she said" approach is counterproductive. I attempted to restore your version of the Gödel article but was reverted (by DFRussia, not Likebox) so it looks like we're going to have to work on building consensus among multiple people who see it the other way before having any success at fixing these articles. —David Eppstein 03:21, 2 November 2007 (UTC)

In any case, it cannot possibly hurt to have more people watching these two articles for a little while. I agree that consensus building is needed here, rather than some sort of appeal to authority. — Carl (CBM · talk) 03:27, 2 November 2007 (UTC)

As Godel's incompleteness theorem has been reverted again, extra help would still be appreciated. — Carl (CBM · talk) 21:17, 5 November 2007 (UTC)

looks like that page can use more attention. i would suggest other knowledgable folks besides Carl take a look, if they haven't done so. Mct mht 00:54, 15 November 2007 (UTC)

Request for comments on GIT

I have made a request for comments here. — Carl (CBM · talk) 19:32, 9 November 2007 (UTC)

Generalized metrics and "pra" as a presyllable

Preclosure operator was misspelled as praclosure operator. When I corrected this, I realised that there is also an article prametric space, and this drew my attention to the zoo of generalized metrics articles. I think there are some serious issues there, but I am not very motivated to solve them alone since it is too far from my main interest. Please see my rant on the talk page for prametric space. I would appreciate help from someone who is a bit closer to the subject.

One particular question: Is there a standard term for something that satisfies all axioms of a metric except the triangle inequality? --Hans Adler 14:43/15:08, 15 November 2007 (UTC)

I'm not exactly sure how standard it is, but the only term I've seen for this concept is a semimetric. Although I've seen semimetric defined in slightly different ways as well. The term doesn't seem to be quite as standard as pseudometric or quasimetric. Outside of Wikipedia, I have never heard of the terms prametric or hemimetric. -- Fropuff 20:28, 15 November 2007 (UTC)

Requests for adminship: Geometry Guy

Geometry guy is a candidate for adminship. His RFA page is here for anyone who wishes to comment. — Carl (CBM · talk) 21:37, 8 November 2007 (UTC)

Many thanks to the many editors here who contributed to my RfA nomination. If anyone needs some assistance requiring admin tools, please do not hesitate to let me know. Honoured and delighted though I feel, I realise that one guy getting a few extra buttons is not a big deal compared with the huge task of improving the mathematical content of the encyclopedia. So I would be even more delighted if editors here have a moment to comment on the A-Class assessment of Homotopy groups of spheres. We are getting close to an FAC here, but the input and backing of this project concerning the content and quality would be absolutely invaluable. Geometry guy 22:35, 16 November 2007 (UTC)

Gene Golub

Surely every numerical analyst in the world is familiar with the remarkable work of Gene H. Golub. Those who knew him personally will be especially saddened to learn that he has just died suddenly and unexpectedly. --KSmrq^T 22:08, 16 November 2007 (UTC)

I've just added him to the list of recent deaths. Michael Hardy (talk) 00:27, 17 November 2007 (UTC)

Megalithic geometry

Editor Snicoulaud (talk · contribs) has just created an article called megalithic geometry and attempted to link to it from geometry. I have reverted the link; probably the article should be deleted as hokum. Have a look. --KSmrq^T 20:41, 11 November 2007 (UTC)

Give Snicoulaud (talk · contribs) an indefinite block and roll-back all his edits! He is a single purpose crack-pot. JRSpriggs 07:16, 12 November 2007 (UTC)

He seems to be creating a walled garden around Alan Butler, Sylvain Tristan, Megalithic geometry, and Salt Lines, cross linking and adding the same sources to all of them. If we AfD one we should take a look at all of them. —Cronholm¹⁴⁴ 08:55, 12 November 2007 (UTC)

Since editors here may not have access to the Alan Butler's book, the following summary from an Amazon customer might be helpful.

The author aims to prove the use of circular pattern on the Phaistos disk, but manages to come up with circular evidence. Pardon the pun, couldn't resist. The basic observations are valid and useful, such as the 30 fields on one side and 31 on the other, but his conclusions beyond this are essentially unsubstantiated. For example: He is assuming a certain number of degrees on the circle (366), and a certain number of arc-seconds per degree, and furthermore that the length measure is a foot, and that there are 36.6 feet per arc-second. If it is so, then the result corresponds to within a kilometre with the circumference of the Earth, which is remarkble. Since it is remarkble, he concludes that it must be true, which is of course a circular argument to say the least. The book is full of similar units and measures that are unsubstantiated. I can not recommend it.

This material might possibly survive as an article on the book, which discusses the claims from a neutral point of view. Geometry guy 10:10, 12 November 2007 (UTC)

Not quite a true walled garden. I found one link outside, to Xavier Guichard, who may have proposed a similar theory. I think he may be notable. — Arthur Rubin | (talk) 13:39, 12 November 2007 (UTC)

I have nominated the article, as well as Salt Lines and Sylvain Tristan, for deletion: Wikipedia:Articles for deletion/Megalithic geometry. (The fourth one has already been deleted.)  --Lambiam 14:11, 13 November 2007 (UTC)

The AfD discussion was closed with the result Delete.  --Lambiam 11:09, 20 November 2007 (UTC)

It has a line in Phaistos_Disc_decipherment_claims; that's probably what it deserves. Septentrionalis PMAnderson 21:16, 20 November 2007 (UTC)

Cleanup using AWB

In the past month or so, several users have gone over large swaths of mathematics articles, leaving the above edit summary. Their edits usually amount to replacing math html with pseudographics characters, e.g. superscripts rendered as x² with x², greek &lambda; with λ, the inequality symbol &le; with ≤, etc. Here is latest that I've come across, but there are many more instances. I personally do not feel that these efforts result in any improvement, think that the term "cleanup" is rather misleading in this context, and dislike such changes for a number of reasons (cf questions below). But should we take a stand on this issue? Here are a few points that I think deserve being addressed:

• It may be preferable to retain uniform style for formulas throughout each article. In that case, should we treat these wholesale changes similarly to wholesale changes in spelling (British vs American English) that are expressly discouraged?
• Is there significant difference in the quality of the mathematical formulas after the changes?
• Do the changes make rendering the formulas more consistent or less consistent across various platforms?
• If in the future all math html will be converted into some flavour of TeX, would we prefer having math html that is closer to TeX and hence more amenable to conversion to a rather ad hoc mixture of html and pseudographics?

Arcfrk 02:50, 13 November 2007 (UTC)

With regard to AWB, superscripts, and Unicodification, I notified some individual editors, and then realized that the preventative measures previously enacted at AWB must have been removed. I posted a notice there, and almost immediately after so did Michael Hardy (apparently not seeing my comments immediately above his!). Within a day we were told that AWB had been fixed so that problem would not continue. However, that does not fix all the pages that were defaced by well-meaning "cleaners". --KSmrq^T 05:17, 13 November 2007 (UTC)

For the sake of speed, we could "clean" them again using the newest version of AWB, provided that it doesn't have any other little bugs. —Cronholm¹⁴⁴ 07:11, 13 November 2007 (UTC)

I think it would be helpful to expand the Wikipedia:Manual of Style (mathematics), specifically on issues such as x² vrs x². Mainly so there is a position on this so we don't get a back and forth changes. If this existed then we could point the AWB'er to the MoS.

There been a long running discussion on Talk:Bracket about the preferred way to render angle brackets simple ascii < > or exotic unicode U+2329 (〈) and U+232A (〉) which does not always appear in browser fonts.--Salix alba (talk) 08:03, 13 November 2007 (UTC)

I have the latest version of Mozilla Firefox and your exotic unicode U+2329 (〈) and U+232A (〉) just look like question marks (?) to me. Use \langle and \rangle in TeX! JRSpriggs 08:16, 13 November 2007 (UTC)

It is a font question, not a browser question. Firefox renders them perfectly fine on my home computer, but I get numbers in boxes on my work computer. If Unicode fonts are widely used on math articles, we should perhaps add a notice that tells people how to install fonts. (I thin kthere are notices like that for articles containing Japanese text so people won't delete the question marks). Kusma (talk) 09:50, 13 November 2007 (UTC)

Angle brackets and superscript numbers are one thing, and if they end up displaying differently then I'd agree with sticking to the non-special-character version. But I believe that for &le; vs ≤ or &lambda; vs. λ both versions are rendered identically in the browser and it's a matter of editor convenience only, not affecting the readers, which we use. In those cases I prefer to use the unicode characters directly because that way it's closer to WYSIWYG when I'm editing. —David Eppstein 16:14, 13 November 2007 (UTC)

Replacing x² with x² makes things worse (I wrote something about this in our Manual of Style recently) and is disabled in the latest version of AWB. Replacing greek &lambda; with λ, the inequality symbol &le; with ≤, etc. does not make a difference in how the pages are rendered, though it probably makes the wikitext easier to read when you're editing the page (at least, I think that's the reason behind the changes).

However, edits which only do this kind of clean-up without changing the rendering (like the one that Arcfrk mentioned) should not be done because they just clutter up watchlists; see the fourth point in the "Rules of use" of AutoWikiBrowser. You may want to remind any editors breaking this rule of it. -- Jitse Niesen (talk) 16:20, 13 November 2007 (UTC) (edit conflict with David)

In the case of math articles in particular, I don't believe that unicodifying the symbols is a waste of resources--the code becomes much easier to read when I can just see ≤ rather than &1232342342; or whatever. I'll stop doing it, though, if it's the opinion of the group that unicodifying shouldn't be done. --Sopoforic 18:53, 13 November 2007 (UTC)

My opinion is that we should generally prefer TeX over Unicode for symbols more complicated than Greek letters or inequality signs. It would be nice if almost all browsers had a rich math font set installed, but I don't think it's extremely common yet. — Carl (CBM · talk) 16:42, 13 November 2007 (UTC)

I don't mind most of these edits, but the following is an abomination:

old: x² + xⁿ

new: x² + xⁿ

Any bot that insists on doing this should be humanely euthanized. Michael Hardy 18:53, 13 November 2007 (UTC)

While editing a page, an "Insert" menu appears below the text. Wikipedia seems to feel that these specific characters are safe:

Markup: – — … ° ≈ ≠ ≤ ≥ ± − × ÷ ← → · §

Result: – — … ° ≈ ≠ ≤ ≥ ± − × ÷ ← → · §

The current HTML standard has been around for a very long time, and so we may also expect support from all browsers and fonts for any named character entities. These include all the Greek characters (and a few variants), as well as a small assortment of mathematics symbols. In my table, the available HTML names are underlined. Among these are &lang; and &rang;. I prefer to use these two entity names rather than a UTF-8 character for three reasons: it tells other editors that these are not less and greater signs, it matches the TeX names, and it works around a browser bug I encountered.

When I have an entity name available, I often prefer to use it. Although it is not WYSIWYG, it is faster than copying and pasting a special character, it is completely safe for editing, and it commonly matches the TeX name (with exceptions like &infin; versus \infty).

I have a short list of pet peeves, markup that leads to ugly pages. Here is what I like to see.

1. Avoid TeX markup inline.
2. Prefer TeX markup for displayed equations, and always use "\,\!" to force PNG display.
3. Trailing punctuation for displayed equations goes inside the TeX markup.
4. When using wiki markup, always use a proper minus sign, never the hyphen-minus character. (The insert menu character beside "×" is fine.)
5. When using wiki markup, do not blindly insert plain spaces in equations (without {{mbox}} protection), as browsers are permitted to break lines at such spaces.
6. Never use wiki italics markup ("''") as if it were TeX "$"; italicize only variables.
7. In date and page ranges, always use &ndash;, never hyphen-minus. (The UTF-8 character is fine.)

I have cleaned up page after page only to see later editors pay no attention to such details, sometimes not even in the same paragraph! Although I will grant Emerson's oft-quoted point about a foolish consistency being the "hobgoblin of little minds", when I see text strewn with mistakes in spelling and typography I naturally suspect sloppiness in everything — specifically, in the mathematics. --KSmrq^T 19:08, 13 November 2007 (UTC)

I agree with all of KSmrq's numbered points above. Michael Hardy 22:42, 13 November 2007 (UTC)

I disagree with 7, finding the difference between the endash and the hyphen trivial in such contexts. Use for minus is another matter. Septentrionalis PMAnderson 21:19, 20 November 2007 (UTC)

... and then if you want to get into advance (ha ha...) stuff:

in TeX, use f(x)\,dx, not f(x) dx

write \frac{\partial^2 y}{\partial x_1\,\partial^2 x_2}, not \frac{\partial^2 y}{\partial x_1 \partial^2 x_2}, i.e. put a small space between the two partials on the bottom. Michael Hardy 22:45, 13 November 2007 (UTC)

An example of what not to do is given by , which is used in {{logic-stub}}. It hurts my eyes.  --Lambiam 18:58, 15 November 2007 (UTC)

FAR for Carl Friedrich Gauss

Carl Friedrich Gauss has been nominated for a featured article review. Articles are typically reviewed for two weeks. Please leave your comments and help us to return the article to featured quality. If concerns are not addressed during the review period, articles are moved onto the Featured Article Removal Candidates list for a further period, where editors may declare "Keep" or "Remove" the article from featured status. The instructions for the review process are here. Reviewers' concerns are here. King of ♥ ♦ ♣ ♠ 01:37, 20 November 2007 (UTC)

An Exceptionally Simple Theory of Everything

Here is another example how media frenzy subverts the scholarly principles on which Wikipedia is ostensibly based. This article reports on a single paper, or rather, e-print (posted to ArXiv a few days ago), with that title. While the sexy title grabbed instant attention of many, I would like to question the wisdom of creating an article devoted to what will as likely as not turn out to be another crank theory. It raises a serious issue that should be addressed, namely,

What constitutes a notability claim?

According to the unanimous opinion of the commentators at the AfD for this article (which ended with the result "Snowball keep"), it's the fact that the media reported on it! With some stretch of imagination, it can, perhaps, be argued that the Daily Telegraph's article is a secondary source, although, obviously, the journalists who wrote the piece can hardly be qualified to make an informed judgement on the merits of the theory. On the other hand, WP:WWIN#Wikipedia is not a publisher of original thought states:

5. Journalism. Wikipedia should not offer first-hand news reports on breaking stories.

As reading the article plainly reveals, in a situation like this, the best Wikipedia can do is offer quotes from blogs of various physists by the way of analysis. Which again begs the question:

Should blogs be considered "reliable sources"?

I can live with the existence of many obscure articles promoting strange theories, but I am greatly alarmed by the argument put forward at the AfD and on the talk page of the article, which can be summarized as follows:

There is public interest in the subject, hence wikipedia should have an article on it, so that more people can be attracted to the subject

If this feedback loop continues, instead of becoming "the sum of human knowledge", Wikipedia may easily degenerate into a media-fed blog dealing with current events or, as in this case, original research. Arcfrk (talk) 05:08, 20 November 2007 (UTC)

Yikes, only four hours on AfD and as far as I can tell nobody who belongs to a relevant wikiprojects was notified or even managed to comment there. I really don't have an opinion on the preprint, but I think that it would be reasonable to reopen the Afd, provided your rational is made abundantly clear; I think many will cite the SNOW as evidence of that it should once again be speedily kept. I would also be careful with the OR claim, because it isn't the article itself that is the vehicle for publishing that research. —Cronholm¹⁴⁴ 06:32, 20 November 2007 (UTC)

I don't see how four hours is enough to determine a speedy keep. I have not made a determination on the article itself, but this closure seems unduly hasty. I just removed 11 duplicate keeps from the article. The last of the 13 people to comment (and vote keep) also added 11 duplicate keep votes. This may have contributed to the non-admin speedy keep. That is probably enough to overturn this closure. --C S (talk) 06:36, 20 November 2007 (UTC)

I undid my removal of the duplicate keeps. It's probably best people see how the page looked when it was closed. --C S (talk) 06:41, 20 November 2007 (UTC)

This paper came to my attention when it was added to E8 (mathematics) somewhat before the creation of the article in question. I was tempted to remove the paragraph, but decided to read the article first. It isn't, it my opinion, a crank theory: it may be wrong (and almost certainly is wrong in the details) but that is different. Is it notable? Well it has attracted comments from leading theoretical physicists, and has been covered in the New Scientist. Of course, journalists are not qualified to evaluate the merits of the theory, and neither is Wikipedia, but that is not our job: we report the verifiable. The article needs to be rewritten to achieve NOR and NPOV, but that isn't alone grounds for deletion.

However, Arcfrk raises some quite serious concerns (which I share) about the way this topic has been handled, and also highlights the dangers of following the trend suggested by this AfD. As Cronholm and C S point out, the AfD was flawed. I suggest a procedural nomination at DRV so that we can have a more thorough discussion of the issue at an AfD. I'm happy to do that this evening (UTC) if no one beats me to it. Geometry guy 09:24, 20 November 2007 (UTC)

I've no strong opinion on whether it is wise to open a DRV, but think the snowball judgement was justified. If a DRV should be opened, isn't it more up to the folks at WikiProject Physics to initiate that? I'm not a theoretical physicist, and, seeing as how many notable physicists have provided a reaction, am willing to entertain the possibility that somewhat different criteria for notability apply in that culture.  --Lambiam 11:33, 20 November 2007 (UTC)

It's in the news. One criterion for Wikipedia inclusion is that if there's a word, a phrase, an idea, an event, an individual, or more, that's alluded to in a general newspaper article, they should be able to come here and find out more. IMO, the snowball keep was entirely appropriate. What is needed, however, is much more informed analysis in the article of what is new in this paper; a gauge of what does and what does not appear to be solidly founded; a discussion of some of the criticisms which have led some people to react so violently against the ideas in the paper; and a gauging of whether or not those criticisms seem to be solidly founded or well informed, in the light of the responses and rebuttals of the paper's defenders.

Our job is to serve the public. There is public interest in this paper. Our job is to help the public understand both the ideas, and what controversy there may be around them, better. Jheald (talk) 11:51, 20 November 2007 (UTC)

Some of this discussion might be carried out more usefully on the article talk page. As for the DRV, I won't take this forward unless there is a strong view here that this is the best way to proceed. Geometry guy 18:43, 20 November 2007 (UTC)

There is no need for DRV. Any admin can re-open a discussion closed by a non-admin. Given the comments made above, I think this should be done so that there can be an actual discussion. TenPoundHammer (if you take a look at his talk page) has been going on a spree of rapid closures, rather recklessly. There is no harm in re-opening this so that people like Arcfrk can voice his opinion. --C S (talk) 07:33, 22 November 2007 (UTC)

I've refrained from commenting on the merits of the article until I've investigated it further, but I have done so now. In regards to Arcfrk's comments, the only thing that really matters for the notability claim is the level of media coverage. The only two good sources are New Scientist and the Daily Telegraph. I also found a Fox News article (in the ext. links section) but it does not count as an independent source since it relies extensively on material from the other two sources. The claim by the "keepers" regarding public interest is somewhat dubious. As the Daily Telegraph and Fox News articles show with their headlines (and as Peter Woit commented on his blog), much of the public interest revolves around the "surfer dude" angle.

Putting the surfing thing aside, frankly, I don't see much difference between this and the Penny Smith thing, which also involved similar sourcing (including a Nature article). There *is* some difference in that the latter also involved BLP concerns; however, that only raises the bar for notability somewhat. I expect if say, some simple error arose in Lisi's paper and he were to start getting extensively bashed, the notability of this theory or his own notability would not be enough to negate the BLP concerns.

In summary, two reliable sources is at the level where plenty of discussion for or against could occur. Notability is certainly not guaranteed nor is the outcome inevitable, like demanded by WP:SNOW. Many people would argue that other factors (such as the standards of New Scientist or the Telegraph) need to be weighed, or have concerns about recentism. My own position is that this seems marginal. It's not a loss to delete the article, nor really a gain to have it, although I know some people are having fun working on it. --C S (talk) 09:00, 22 November 2007 (UTC)

reference tool

Thanks to the help of CBM/ Jitse Niesen and KSmrq who helped by pulling out the citation templates of WP math articles/providing improving remarks on the database, there is now a database containing the references of all WP math articles (as of approx. September 07). There are 5300 references, written by some 6000 authors. You can access the database at http://zeteo.info. The references are linked to their corresponding authors, publishers, and journals respectively. An author/publisher/journal is a separate database entity, thus providing the correct structure to uniformly host additional information like wikilink of an author, issn of a journal etc.

More or less manually I fed the data into the database. It was quite a bit of work to do this. I haven't attempted to verify the information which is now in the database. An in-depth check of a small sample of templates showed, that the stuff is generally pretty well-done, though. Using worldcat.org, I manually added ISSN's for the some 120 (total: 1200) journals. Hence, even merely recopying the result of the database most often improves the presentation of a reference. For example, in Atiyah-Singer index theorem, a reference reads

• Atiyah, M. F.; Segal, G. B. (1968), "The Index of Elliptic Operators: II", The Annals of Mathematics 2nd Ser., 87 (3): 531–545 .

The output of the corresponding entry in the zeteo database is

• Atiyah, Michael Francis; Segal, G. B. (1968), "The Index of Elliptic Operators: II", Annals of Mathematics. Second Series, 87 (3): 531–545, ISSN 0003-486X {{citation}}: Check |author1-link= value (help); Check |journal= value (help)

(notice the ISSN, wikilink of the first author, the page formatting using en-dash, the wikilink of the journal, the full name of the journal. The latter is achieved via a manually added redirect similar to the ones for WP articles).

Several options are available; for example it is easy to let it put out something like

<ref>{{citation|...}}</ref>

for those who prefer footnote-style referencing. For your commodity, there is a little search engine template similar to the google toolbar etc., which can be integrated in the browser's menu. So, no excuses anymore :-) for not referencing an article when you actually know a reference off your head.

Anybody can add/update database items. It is possible to import bibtex files and let the database parse them, so you can relatively comfortably add the items of your personal bibtex file (it's pretty quick, I did 6.000 of them). A brief documentation can be found here, bugs and questions etc. can be reported here.

Enjoy! Jakob.scholbach (talk) 22:49, 20 November 2007 (UTC)

I'm a little confused. Clearly not all the references of mathematics article are in the database, including many that I've included in articles. Is it because only those formatted with a template have been included? --C S (talk) 09:06, 22 November 2007 (UTC)

Yes. Only references using the cite book, cite journal and citation templates have been used. The reason for this is that it is hard/impossible to pull non-template reference information out of the articles and parse it. Moreover the quality of those references is often considerably worse than where templates are used. Jakob.scholbach (talk) 09:35, 22 November 2007 (UTC)

This could be very useful for me. How is adding references from Wikipedia source supposed to work? I pasted the references section of model theory into the textfield, clicked "parse this text", and got an empty template. The references (reformatted as templates very recently) still don't seem to be in the database. --Hans Adler (talk) 14:05, 22 November 2007 (UTC)

Thanks. Embarassing. I didn't know that the templates also work as {{ cite book ...}} instead of {{cite book ...}} (without space), hence the parser is not yet up to this variation. This is now fixed. I'll fix this very soon. In the meantime, if you manually delete the leading space between the braces and "cite", it works (click at "add a reference from file" etc.). The DB currently contains only the reference templates as of September, which is probably why you didn't found the recently formatted references. Jakob.scholbach (talk) 20:28, 22 November 2007 (UTC)

Excellent. I am looking forward to using your tool regularly. Thanks a lot! --Hans Adler (talk) 15:34, 22 November 2007 (UTC)

Average

Please add your opinions on article simplification here.[6] --Foggy Morning (talk) 02:10, 23 November 2007 (UTC)

List of things named after Paul Erdős

The Erdős disambiguation page included a moderately long list of things named after Paul Erdős. I created a new page called List of things named after Paul Erdős. I moved all those items to that page, and left a link to it on the disambiguation page. If there are other things that should be listed there, please add them. Michael Hardy (talk) 18:12, 22 November 2007 (UTC)

I'm not sure what to do about it, but there's a lot of overlap there with Erdős conjecture. —David Eppstein (talk) 18:23, 22 November 2007 (UTC)

Forgive me for speaking out of turn, but aren't the items of Erdős conjecture a subset of List of things named after Paul Erdős? Merging/redirecting the former into/to the latter seems an idea worth considering. --The Brown Bottle 18:29, 22 November 2007 (UTC)

I believe Erdos was known for his conjectures, as well as for his collaboration and other mathematical work. Perhaps they should still be kept separate. — Arthur Rubin | (talk) 20:53, 22 November 2007 (UTC)

I see no reason for either of these articles to exist. The material is not large and could be included in Paul Erdős to the benefit of the project. I suggest this be done before they are proposed for deletion. --Bduke (talk) 21:43, 22 November 2007 (UTC)

I don't know about proposals for deletion, but it certainly looks like merging could be considered. Erdős conjecture has the potential to become a nice section of Paul Erdős. A redirect to that section could take over the disambiguation function. (Or is a redirect to a section a bad idea?) Most of the things in List of things named after Paul Erdős are either conjectures or already in the "See also" section of Paul Erdős, so that shouldn't be a problem either. --Hans Adler (talk) 00:58, 23 November 2007 (UTC)

It does seem like a page that could expand greatly -- sure, a list of 10 or 15 things could easily be rolled into the main article, but what happens when 30 more things are added? I think a page for this could prove useful. CRGreathouse (t | c) 04:14, 23 November 2007 (UTC)

• The magnitude of Erdos' conjectures was so great that many papers are titled for it. For example, I read a doctoral dissertation (about the existence of a graph with certain constraints) titled "on a conjecture of Erdos" (Hsu, Stony Brook, around '81). I would expect that an article listing (some of his better known) conjectures would grow, and could grow quite large. Pete St.John (talk) 18:47, 23 November 2007 (UTC)

But it is not large now, so add it to the main article and then hive it off when it does get too large. --Bduke (talk) 23:47, 23 November 2007 (UTC)

I would agree, were it not for the fact that the list was split off from a disambiguation page. I think that users should be able to navigate through the disambiguation structure without needing to chew through substantive articles in order to find the article they are looking for. (And this consideration holds in particular while the list is short and thus difficult to locate among the biographical information about Erd{\H o}s himself.) –Henning Makholm 00:04, 24 November 2007 (UTC)

Stalled move request

(cross-posting Portal_talk:Mathematics#Stalled_move_request:)

Two weeks ago I proposed to move Lists of mathematics topics to Portal:Mathematics/Lists. The request stalled for reasons explained at the WP:RM page (5th bullet of the linked section). More elaborate explanations for the stalling exist, most of them linked from the indicated WP:RM page section.

Basicly I ask the people of the Mathematics portal (and the mathematics project) to weigh in whether they think it a good idea to accept the "list of lists" page as a sub-page of the portal, hoping this would get the situation afloat again. The actual move proposal is discussed at Talk:Lists_of_mathematics_topics#Requested_move.

One of the issues is whether the mathematics "list of lists" page should lose its "featured" status. If it is kept in main namespace, I think it should, for WP:V and WP:NOR reasons (e.g. the only external sources are mentioned in the intro, second paragraph, but explaining they are deliberately ignored for no other apparent reason than wiki organisation). If the list is moved to portal namespace that reason for de-featuring ceases to exist (although featuredness should possibly be reiterated as a portal page). --Francis Schonken (talk) 10:55, 24 November 2007 (UTC)

PS, I proposed Portal:Mathematics/Lists as new page name by analogy to dozens of "list of lists" pages in Portal namespace --Francis Schonken (talk) 11:00, 24 November 2007 (UTC)

The page has been moved, as I see. I am not sure it is a good idea, I think the old place, list of mathematics topics was better. Oleg Alexandrov (talk) 02:56, 25 November 2007 (UTC)

I'm inclined to agree. And it's a very weak discussion. Very very few people participated. Michael Hardy (talk) 04:00, 25 November 2007 (UTC)

overturn

We should overturn this move. Hardly anybody commented on it. We should solicit the opinions of about 500 Wikipedians who frequently edit mathematics articles. Michael Hardy (talk) 04:08, 25 November 2007 (UTC)

No consensus at all was reached on this move. This is bogus.

I've moved it back.

There was no consensus at all for this move. The cited page on which the consensus was reached did not reach a consensus. And I didn't recognize even one name among those who commented there. HUNDREDS of daily Wikipedia editors have each edited HUNDREDS or (in my case and that of many others) THOUSANDS of mathematics articles, and they didn't participate in the discussion. We should broadly canvas to solicit opinions of those hundreds of mathematicians who edit here.

Oleg, you're experienced with bots, about which I know nothing. Is there a quick way to compile a list of frequent math editors to ask for their opinions on this? Michael Hardy (talk) 04:17, 25 November 2007 (UTC)

I think we better wait for people to comment here. Oleg Alexandrov (talk) 04:55, 25 November 2007 (UTC)

Maybe this is over. Someone closed the discussion as "no consensus". Then someone (the same person?---I don't remember) entered and said there was a broad consensus, on some other page! And then moved the article. On that other page the topic was not mentioned, except tangentially once or twice and no one seemed aware of the page in question. This project was notified of the discussion, but not of the other discussion on that other page. Experience makes me anticipate that in situations where illiterates solemnly declare themselves omniscient when making decisions about math articles and then tell people who've edited literally thousands of math articles and who know something, to go screw themselves, or something similarly polite, then they won't retreat politely. But let's wait and see what happens. Michael Hardy (talk) 06:06, 25 November 2007 (UTC)

Template for forcing non-italic units (e.g. in formulas)

In some circumstances, one wishes unit symbols (cm, etc.) to always be upright (i.e. non-italic), even if enclosed in an italicized phrase, e.g. so as not to be confusable with italicized variables which might coincidentally use the same characters. I've created the template {{itunit}} to do this for us trivially, without violating the XML semantic integrity of the XHTML italicized phrase that is output (which necessarily includes the unit). Instead of stopping and starting the emphasis, as in only ''3'' cm ''wide'' at the base, you simply wrap the unit in the template: only ''3 {{itunit|cm}} wide'' at the base (which yields "only 3 cm wide at the base", visually, without breaking the <em>...</em> XHTML span around the entire italicized phrase, as received by the browser). Enjoy! PS: Please feel free to notify other wikiprojects that may find use for this; I'm not a particant in the science & math projects, but created this to resolve a fight over at WP:MOSNUM. — SMcCandlish [talk] [cont] ‹(-¿-)› 17:25, 24 November 2007 (UTC)

Erdős number‎ categories nominated for deletion

Removed cfdnotice, cfd has completed. --Kbdank71 17:38, 9 May 2008 (UTC)

This is the third nomination and with the concerns last time that the Math WikiProject wasn't notified I'm making sure you are the first to know about it this time around. __meco 13:51, 28 October 2007 (UTC)

Please note, "endorse" vs "overturn" at the deletion review page

At the Deletion Review Page, where folks are discussing wether to overturn the deletion of the Erdos Number Categories, some folks are voting "endorse", with comments suggesting they mean "endorse the category". Unfortunately, "endorse" in this context means "endorse the closure of the ballot to delete", i.e. the deletion. I think most of us want to vote "overturn". There are examples of both kinds of votes, with clarifying comments, at that deletion review item and in other items near it. We certainly can't show any consensus if we vote mistakenly :-) Thanks, Pete St.John 19:18, 7 November 2007 (UTC)

---

The crazies have won, Erdős number categories are no more. See the archived discussion, where the summary is

• The result of the debate was delete. I honestly don't have time to explain every reason why. Strength of argument lends to those who wanted to delete. For the vote-counters, many of the "keeps" relied on the argument "nothing has changed since the last time", which isn't a strong argument at all, and certainly pales to the arguments that the delete people brought up. There were some good arguments on both sides, but as I said, the ones who wanted to delete had the stronger argument. Kbdank71

In other words, the fact that we have made the same arguments so many times we did not see the need to repeat them counted against us! Whatever one thinks of the category, this is an absurd justification for deciding the debate. If there are strong arguments on both sides, the correct result is keep, from lack of consensus. --KSmrq^T 16:15, 2 November 2007 (UTC)

It's fine to disagree with the closure of a CFD, but labelling those who you disagree with as "crazies" is a breach of WP:CIVIL and WP:NPA. --BrownHairedGirl (talk) • (contribs) 11:36, 4 November 2007 (UTC)

It is, indeed, a breach of civility as defined in Wikipedia terms. Then again, continuing to bait someone who's obviously frustrated with the decision is not exactly a wonderful thing to do. This would be a good moment for you to back off. --Bogwoppit 11:46, 4 November 2007 (UTC)

In a probably forlorn attempt to stop another pointless fight, I will point out that Erdos numbers are nothing but a joke, one of the points of which is to fool people into taking them seriously. There sure seem to be a lot of people who have not yet figured this out. R.e.b. 16:59, 2 November 2007 (UTC)

If they're a joke, that's no reason not to take them seriously. The point is that it's a cultural meme. No one takes them seriously (I think?), but the fact that this cultural phenomenon exists should be reported in a serious way---that is the sense in which they should be taken seriously. Michael Hardy 22:45, 2 November 2007 (UTC)

Sounds like a joke Erdős might have enjoyed.

As I said, however, regardless of one's opinion about the benefit of the category, there was clearly no consensus to delete it, and the admin has acted improperly and with an unacceptable explanation. How would you feel if the deletion target was, say, Category:Bourbaki ("initially a clever prank", says the article)? Don't kid yourself that it couldn't happen. --KSmrq^T 18:04, 2 November 2007 (UTC)

If you do not like it, take it to Wikipedia:Deletion review. The meme is significant and it is dealt with at Erdős number. However it is absurd that articles such Linus Pauling, Edward Teller, Louis de Broglie, Jonathan A. Jones and Kenichi Fukui, just to name the ones that came up on my watchlist to delete the category, should be cluttered up with this joke category. Their Erdős number is completely non-notable. --Bduke 01:01, 3 November 2007 (UTC)

I assume you're referring to the policy WP:N, which has nothing to say about article content, only whether or not each specific article exists. It has no bearing here. --Cheeser1 04:02, 3 November 2007 (UTC)

Well, no I was not. I was using the word notable in its usual sense, not the WP:N sense. Perhaps I should have used trivial. The Erdős number is interesting and it is fun, but it is completely trivial and inappropriate to put Nobel Prize Chemists into this category. On other issues, I was not impressed by the closing admin's reasons, but as I said if you do not like it, put it to WP:DLR.--Bduke 08:48, 3 November 2007 (UTC)

While personally I would have preferred that the categories had been kept, to be honest that's mostly just because I thought it was sort of cool to be able to find mathematicians' Erdős numbers easily; I couldn't think of any strong argument that it was something that belonged in the category system, which is why I didn't contribute to the deletion discussion. While I have to allow that KSmrq has a point about the closing admin's handling of the situation, I do think he probably got to the right result.

Main point being, let's not let this turn into a math-wikiproject-against-the-world issue. It's not worth the political capital, especially when the argument one might make on the underlying substantive issue (as opposed to complaints about the closing admin) is so weak. It would be reasonable at this point to recreate a list article, I think, if one was deleted on the grounds that it was redundant with the categories, or to create a new one if one never existed. --Trovatore 04:24, 3 November 2007 (UTC)

Something to that effect seems to be going on at User:Mikkalai/By Erdos. —David Eppstein 05:18, 3 November 2007 (UTC)

I also liked the convenience of being able to scroll down to the bottom of a math biography article and see the subject's Erdos number. One suggestion on the talk page was to put the information in an infobox, instead. [7] --Ramsey2006 15:10, 4 November 2007 (UTC)

I would suggest a compromise, that it might be more appropriate to have a Category:Mathematicians by Erdős number: I'm not persuaded that Erdős number is an interesting categorization for people in general, and I think it should be listified, but for some mathematicians there is an interest in categorization by Erdős number, even if it is just a meme and a joke. Such a category might more easily survive the attention of the streamliners. I nearly mentioned this in the debate, but there was obviously more heat than light there so I stayed out of it. Geometry guy 20:55, 4 November 2007 (UTC)

Reasons to reverse the deletion

• promoting the effective concensus. If every issue were decided by a vote ("is pi transcendental?") most technical issues would be decided wrongly. It's not enough than non-specialists don't understand something, to be justified in destroying it. Democracy needs mechanisms for merit to intrude into policy. Note the current political issue in America, where "separation of church and state" protecting the teaching of Darwinian Evolution in public schools, can be subverted by Creationists simply redefining themeselves as Creation Scientists (so their view is Science, not Religion). They publish their own papers with their own peer-review in their own journals. How is that science, to be distinguished from "our" science, in the courts? The general process of promoting truth (in the sense of propositional calculus, or in the sense of scientific induction) in a world dominated by public opinion, judicial truth, Revelatory Truth, and others, is not trivial. We have to live in this world.
• Support for the Category is not just a clique of wikipidians, but a profession. For example, Ron Graham, a former president of the AMS, "popularizes" Erdos Numbers.
• Erdos' indiosyncracies, unprecedented touring, profligate production, and brilliance are legendary, in fact iconic. Erdos Nubmers have (increasingly) historical and (diminisihing) socio-political significance to mathematicians. Also the Numbers so some extent memorialize the man in a more approopriate way than merely naming a theorem for him.
• This category is in no way less meaningful (nor, perhaps, more meaningful) than categories such as persons born on certain dates, or who live in certain cities, etc. Summary deletion of those categories would evoke a hew and cry from the special interest group that does care. This is a natrual process, and mathematicians need to be able to hew and cry also, as deductive logic is not necessarily effective on the deletionists.
• I have a theory that the deletionists are concerned with "defining people by numbers" perceived as an evil activity, and conceived with very murky notions of "define" (and even "number", e.g. they are confused about Erdos Numbers being upper bounds). If they understood the subject they may not be afraid of it. So part of our motiviation is education, but in a meta-mathematical topic that is outside our usual methods of teaching, e.g. I can't prove that the category should not be deleted, in the same way I would prove L'Hopital's Rule. Pete St.John 22:50, 6 November 2007 (UTC)

Admins do as admins please. I don't think this is going anywhere, even with consensus on its side. CRGreathouse (t | c) 00:54, 7 November 2007 (UTC)

There was no reason to delete this, except that some people see it as their job to tear down the work of others.Ryoung122 02:43, 8 November 2007 (UTC)

That's not a fair or appropriate accusation. As much as any of us might disagree with the actions or opinions of others, we should not be jumping to such accusatory conclusions. As for the "admins do as admins please" - I suppose that is true, and perhaps that's a systemic problem on a wiki like this, but that doesn't mean it isn't worth making an honest effort to do something (be it overturn, or listify, or something). --Cheeser1 05:42, 8 November 2007 (UTC)

Reversing the Deletion

I've requested a Deletion Review, at this deletion review log item. It's awkward because of the related categories Erdos Number <<X>> that got destroyed, not to mention variant transliterations of "Erdos". But Wiki has a mechanism for consensus among admins, similar to consensus among editors for ordinary contributions, and I think it's fair to give that mechanism a chance to work. Pete St.John 18:23, 7 November 2007 (UTC)

Status at this writing

The original vote to delete the category (in this recent 3rd attempt to delete it) had been 11-5 in favor of keeping it (not counting an anonymous IP who voted to delete). The Admin deleted anyway, on the grounds of prefering the arguments to delete. Currently, at the Deletion Review where I have requested overturning that deletion, the vote is close, 6 to overturn and 5 to endorse (the deletion). This isn't the overwhelming 2-1 majority that lost anyway to admin fiat, but I think the standards may be different in a Deletion Review among admins, than the standards applied by an admin reacting to editors. I think at least we are showing the admins that we have a beef. Personally, it seems to me that while we tire of rebutting the same circular objections perpetually, to no apparent effect, the deletionists do not tire. They are like vampires who crave blood but can't be killed. Pete St.John 22:35, 7 November 2007 (UTC)

I don't think it's helpful to refer to this process as a "beef" or to call people vampires. We have plenty of points to make on their own merit, and don't need to make this process any more hostile or tense than it is. --Cheeser1 00:21, 8 November 2007 (UTC)

What is all this talk about "among admins"? DRV isn't for admins only any more than CfD is. The only difference is that DRV is for reviewing a deletion, not simply talking about whether an article should be deleted. JPD (talk) 12:51, 8 November 2007 (UTC)

Seemingly that's my mistake. I had construed the Deletion Review as pertaining to admins, I asked for clarification, and the clarification was ambiguous ("anyone can comment" and it seems to mean "the votes keep/overturn are just comments too, in this context"). So we can all "vote", that's great. Thanks.Pete St.John 19:33, 8 November 2007 (UTC)

Yeah, I would suggest that in spite of the passions there should be a civil and constructive atmosphere. Demonizing your opponents is a rather poor taste tactic, at least on Wikipedia. Oleg Alexandrov (talk) 15:57, 8 November 2007 (UTC)

• Two things; first, does "demonizing your opponents" refer to me? I have been somewhat more liberal in my characterization of the predominant opposition, in my expressions here. I have a very low opinion of their rhetoric and practices, but anyway please feel free to point to particulars that you consider excessive.
• Second, I have, in fact, been formally accused of unethical canvassing practices. Cf this item at my talk page, which includes a link to the "ANI" item. I may be misinterpreting the ANI process, it's new to me, but it seems to be a mechanism for addressing unethical practices. I posted my rebuttal there, I'm happy with it so far, but I'm in personal trouble atm, which may detract from my (relatively militant) advocacy of the Erdos Number issue. Some would say that is a Good Thing. Pete St.John 19:33, 8 November 2007 (UTC)

You have posted notices on the pages of individual mathematics contributors about the deletion review. Bad idea; interested parties will see a single notice posted on this page. You have also sometimes slanted your notices to favor overturning. Bad idea; even among mathematicians opinions differ on the merits of these categories, and it is far better to merely urge participation with no prejudice about what the outcome should be.

In the review itself, any editor may participate; admins have no special status. The purpose of the review is not to rehash the arguments for and against deletion. The relevant question is whether the admin who closed the debate acted properly. For example:

1. The closing summary said arguments from the two prior debates should carry no weight; is that correct procedure?
2. The closing summary said good arguments were made on both sides, but the closer preferred one side; is that correct procedure?
3. Numerically, the comments in the debate were overwhelmingly in favor of retaining the categories, the opposite of any consensus for deletion; was the closer right to impose an opinion without the support of consensus?

Wikipedia will not be destroyed if the categories are retained, nor if they are deleted. It will be in serious trouble if decisions are too often made at the whim of an admin.

I have been criticized for saying the crazies have won. I stand by my characterization. Repetitive shouting and a partisan close is no way to run an encyclopedia. That is not to say that everyone who did not support the categories acted crazily, nor that everyone who did support the categories acted properly. My concern is that the process was fatally flawed. Craziness has won.

My greater concern is that in the recent past we have had other examples of bad deletion decisions, suggesting a systemic problem rather than a single aberration. --KSmrq^T 21:06, 8 November 2007 (UTC)

(I'd prefer to keep my post in one piece. Also, the deletion review is the proper place to actually discuss the merits; I'm just indicating the kinds of questions that are relevant for a DRV. --KSmrq^T 00:35, 9 November 2007 (UTC))

• note: Originally I posted my rebuttals (including answers to questions) with the points (including questions). For reasons of his own, Ksmrq has removed my answers to a continuous section (below), which now reads confusingly. I don't believe it's very important now, but to see the answers along side of the questions, one can use the revision history of this page.Pete St.John 23:45, 9 November 2007 (UTC)

I myself didn't notice the category deletion until a bot modified several pages I watch. I only just joined the wikiproject, watching this page, on account of this controversy. Alot of mathematicians are interested in mathematics so much more than in politics :-). My feeling is that we were rail-roaded, by a glib result contrary to a clear majority, and that we are still being swamped by a spam-like process of recurring, circular rehashes, so I felt, and feel, that it's important to get out the vote. Democracy loses if only anarchists vote. Quadratically loses. As for slanting my notices, I am deliberating attempting to countervail a movement. I have a side. I take not of guidelines about canvassing and I'm seeking to work within them, but I'd be lying if even pretended to sound indifferent. Pete St.John 21:24, 8 November 2007 (UTC)

1. I'm no expert on the procedure. I would assume that the votes would carry no weight, but the arguements themselves would be fair to cite. The admin, Kbdank71, plainly and energetically supports deletion. Pete St.John 21:24, 8 November 2007 (UTC)
2. apparently the admin who closes may rule against the majority if the arguements favor the minority. Kbdank71 stated his opinion that the arguements for deletion were stronger. He can't seem to point to any specific one that hasn't been rebutted over and over. Admins have alot of latitude, I believe he abused that latitude. But we don't have laws and courts, we have guides and reviews. I seek review. Pete St.John 21:24, 8 November 2007 (UTC)
3. Kbdank claims that the arguements for deletion were better than the arguements for keeping, which may be interpreted to mean the consensus was not reflected by the majority. IMO the overwhelming vote opposing him (11-5, not counting the Anonymous IP that voted to delete) is a plausiblity arguement that he did not judge according to the consensus, as he is guided to do. Pete St.John 21:24, 8 November 2007 (UTC)

I wholly agree. I think the editorial process is more important than the Erdos categories themselves. The majority rules, but should not ignore minorities. Pete St.John 21:24, 8 November 2007 (UTC) but I should clarify, in this case the majority lost. Pete St.John 21:26, 8 November 2007 (UTC)

In my view craziness has scored a victory; bringing the same issue to vote 3 times, losing every time, then making a fiat contrary to any sane assessment of consensus, and railroading and blindsiding affected users. But craziness hasn't won. Not if we don't give in to this. Pete St.John 21:24, 8 November 2007 (UTC)

I'm not coping elegantly with just this one. But, "stuborn-ness in the cause of mathematics is no vice" :-) Pete St.John 21:24, 8 November 2007 (UTC)

Continuing discussion

Discussion here about the best way to present Erdos numbers in articles is perfectly appropriate. But some editors are concerned that the discussion might be intended to disrupt the ongoing DRV. I don't think that is actually the case, but I hope everyone will keep it in mind, to foster collegiality. As usual, there is no massive conspiracy, just a disagreement about the best way to do something. — Carl (CBM · talk) 16:12, 9 November 2007 (UTC)

The Deletion Review has been closed,and the deletion overturned. --Ramsey2006 03:38, 10 November 2007 (UTC)

After closing (early!) as "overturned", the closer reversed the decision.[8] See also Wikipedia talk:Deletion review/Log/2007 November 7#Regarding the Erdos number categories.  --Lambiam 06:24, 10 November 2007 (UTC)

This whole thing is quite confusing. Aparently, (as SparsityProblem notes here [9]) it was closed early, as the rules require it to be open for 5 days before closing. Wikipedia:Deletion review#Closing reviews Looking back through the November DRV pages, I could onlly find two that were listed for a full 5 days before being closed, in violation of the rules for closing DRV's. (All of the other DRV's on that same day as the Erdos number DRV have already been closed.) Will they all be reopened, now? --Ramsey2006 10:14, 10 November 2007 (UTC)

Relisted

An editor has asked for a deletion review of Category:Erdős numbers. Since several of you participated in the previous discussion for this category, you may wish to participate in this relisting of the deletion review. The previous one was apparently closed as "relist" due to canvassing. - jc37 09:23, 10 November 2007 (UTC)

Closed

The second DRV for the third CfD of the Erdős numbers categories (whew!) has been closed. In the best tradition of Solomon, the result will satisfy neither extreme completely. Here is the closing summary:

---

• Category:Erdős numbers – From the discussion below, I think two conclusions can be drawn on which there is wide agreement: 1.)Erdos numbers are trivial, and in general do not correlate to the significance of a mathematician or her/his work; 2.)Mathematicians value Erdos numbers as a significant facet of their shared common working culture. It is for this reason that Wikipedia has an article on Erdos number, and no one in this discussion has questioned the encyclopedic worth of that article.

These two conclusions are in tension with each other. Trivial information is not used in categorizing encyclopedic material; yet, although this information is trivial, many Wikipedians in the mathematics field are passionate about this trivia, and find it worthy of mentioning.

It is argued that Erdos numbers are not "a defining characteristic", and are thus inappropriate for categorization; it is counter-argued that many current categories appear to exist for characteristics whose "defining" nature is ambiguous at best -- eg. "People from Ohio".

What seems to have been lost to some of those commenters urging that deletion here be overturned is that deletion of the categories does not serve to eradicate Erdos number data from Wikipedia. Individual Erdos numbers may be added to each mathematician's article; and lists, as appropriate, may be maintained. Categorization is about reader navigation and no clear compelling case has been made regarding why readers would wish to navigate among mathematicians on the basis of their number. Passion aside, an individual's number is not known to be that highly significant.

Having said that, the proponents of undeletion have one significant point in their favor -- the nature of the previous discussion did not delineate among the various Erdos values, and it did have the ability to consider the full range of options (listing, "infobox"ing) now suggested. Hence, it is logical and just to relist "cat:Erdos number 1" at CfD. If arguments for Erdos numbers as a "defining charactristic" can be made, they should apply most strongly to this "high" number. A limited relisting will also allow full discussion of the "list" and "infobox" alternatives.

Erdos numbers will survive at Wikipedia, and it should remain easy to determine the number for any modern scientist who might have one. Given the admitted trivial nature of the numbers, it seems categorization on that basis is highly unlikely to be appropriate. Hence, the deletions are endorsed. Nevertheless, further discussion is warranted to ensure that no evidence in favor of the importance of Erdos numbers was overlooked in the previous en masse CfD, and to clarify the question of what to do with the Erdos data of individuals, in the full light of all alternatives. Hence, a limited relisting at CfD is proper. – Xoloz 21:54, 14 November 2007 (UTC)

---

Now, as it happens, I am not convinced that there is widespread agreement on the first point; however, it is true that editors both outside and inside the mathematics community have said something along these lines. I am puzzled that Xoloz has considered the merits of the arguments for and against deletion, rather than simply acknowledging a lack of consensus. This again seems to set aside community decisions in favor of one admin's choice. The closer's syllogism is: • Erdős numbers are widely considered trivial, • trivial data is inappropriate for categorization, therefore • Erdős numbers are inappropriate for categorization.

If Erdős numbers are meant to be fun trivia, I'm disheartened; this process has destroyed most of the fun for me. The category for Erdős number 1 will be relisted. Those who have not been thoroughly beaten down by the opposition, and who feel they can refute the Xoloz syllogism, may wish to participate. If you choose to do so, I strongly suggest concise, fact-filled arguments. In particular, do not let opponents bait flamewars; do not discuss motives; do not revisit past conflicts. --KSmrq^T 22:56, 14 November 2007 (UTC)

Syllogism or not, the closing administrator gave a very careful analysis of the arguments, found a reasonable compromise, and pointed out one undeniable fact (inconvenient truth, if you wish):

no clear compelling case has been made regarding why readers would wish to navigate among mathematicians on the basis of their number.

Arcfrk 00:44, 15 November 2007 (UTC)

Compared to the close of the first DRV, this one meets my criteria for sanity. Indeed, the closer makes it abundantly clear that this is a reasoned and principled decision, with concessions to both sides. To my eye it still substitutes admin opinion for consensus, but the relisting of at least one category allows consensus to be asserted once more by those who have the stomach.

I have tried to keep my opinions about the worth of the categories out of debates that concern process, but perhaps now is an appropriate time to reveal that I personally have no objection to keeping them, but would not go out of my way to create or maintain them. As I have said previously, shouting over opposition and closing with a strong appearance of bias are a bad way to run an encyclopedia. Many of the "overturn" entries in the DRV said much the same thing.

The repeated CfD's and resulting fatigue still concern me. In the (second) DRV, one comment — perhaps the most strident — said, "[B]ury the categories under fifty feet of dirt, and stomp on them repeatedly." The unending bombardment of posts by that editor acted out that sentiment with passion. It was an ugly process, not worthy of Wikipedia. --KSmrq^T 04:42, 15 November 2007 (UTC)

My understanding is that the Deletion Review process is meant to be consensus building, and the overturn in question emphatically did not reflect consensus (and therefore by policy should have been ruled "keep"). I plan to bring a Request for Arbitration but it will take quite a bit of time. I believe it is very important that admins not be seen to fecklessly trample on clear, well-enunciated consensus by mere fiat. Pete St.John 23:19, 14 November 2007 (UTC)

Question. Is somebody going to post somewhere, or maybe already posted, where the new (to the Nth power, for some value of N > 4 but < googleplex) discussion is? The...Category For Deletion, as opposed to the Deletion Review. I believe this is the 4th Category for Deletion (CfD) with an interuption of two Deletion Reviews (DRv?). Or are we just blowing that off? I have to post there as a matter of form, I suppose, but my continuting effort will be developing the case for Arbitration (RfA). Pete St.John 19:41, 15 November 2007 (UTC)

It's here: Wikipedia:Categories for discussion/Log/2007 November 14#Category:Erdős number 1 Personally, I'm pretty much blowing it off at this point. I don't see much point in trying to save it for a single category. Nor do I really see much of an arguement for an Erdos number 1 category that would not equally apply to the other categories that are not being discussed there. Except for the fact that they are less subject to change, arguements specifically directed at a particular Erdos number seem to me to misrepresent what the numbers actually measure. And such arguements seem to me to feed into the notion that they are supposed to be some sort of measure of mathematical ability/stature, a "defining characteristic", etc, rather than an interesting and rather widely popularized, if somewhat amusing and light-hearted, but still cherished, aspect of mathematical culture. It also legitimises what seems to me to be an unrealistic and unreasonable requirement for having the categories in the first place. --Ramsey2006 21:33, 15 November 2007 (UTC)

(Ramsey, thanks. I was just posting the following and we edit conflicted) The new Category for Deletion (CfD) discussion is at this CfD. Aside from being the 4th CfD, interupted by two Deletion Reviews and one AN/I, the specific topic has been changed yet again; "keep" means "restore the deleted category Erdos Number One" and "delete" means "leave it deleted", and the other Erdos Number categories are no longer under discussion. Also, the correctness of the previous closures is no longer under discussion. I've "cast my vote" there and explained why I do not expect to follow the debate; there have been numerous inexcusable procedural errors, suggesting a pattern of malfeasance, and that is beyond the scope of a CfD. Pete St.John 21:37, 15 November 2007 (UTC)

regarding "...legitimizes...", yes, I agree. So I "voted" Keep, with Strenuous Objections. The RfA will be the place for this. Pete St.John 21:39, 15 November 2007 (UTC)

List/Infobox combination

I think that at this point, we should consider the creation of Erdos number lists together with a Mathematician infobox template shamelessly plagerized from the Scientist infobox, that would contain a field for Erdos number, and would also have a link to the Erdos number lists for ease in navagation. I think that a separate Mathematician infobox is preferable to attempting to add the Erdos number field to the Scientist infobox because such an optional field was once part of the scientist infobox, and was deleted in a previous deletion discussion, along with the left/right handedness field with which it was compared. Seems to me like a battle not worth refighting. I think that as a practical matter we can reproduce most of the usefullness of the Erdos number categories in this way, while avoiding (hopefully!) all the controversy and wasted energy that goes into the category stuff. As for the possibility of retaining a a single category for Erdos number 1, I can't really see the need for the category if it just acts as a parallel system to the proposed list/infobox combination. One system is easier to maintain than two parallel systems. I propose that we don't even bother with relisting it ourselves, and if it gets relisted anyway, focus instead on attempting to use the relisted CfD to get a solid and undeniable consensus for allowing the list/infobox combination that we can point to later, so that we can build up the list/infobox combination without having to worry about having to fight any more silly battles over it in the future. --Ramsey2006 00:15, 15 November 2007 (UTC)

How do you propose to handle people whose primary appointment is not as a mathematician, such as (among those with EN=1) Václav Chvátal, Ronald Graham, Maria Klawe, Brendan McKay, and Mario Szegedy? —David Eppstein 00:31, 15 November 2007 (UTC)

Well, to tell you the truth, if it is possible to get the optional Erdos number field readded to the Scientist infobox without a fight, then that would seem preferable to a separate Mathematician infobox. I'm just not sure that I'm up for another battle with Erdos numbers getting compared with left/right handedness, as they were in the discussion that led to the removal of the optional Erdos number field from the Scientist infobox. (BTW, I'm surprised to see Ronald Graham on that list. I thought that his primary field was math. I have linux on my laptop mainly so that I can run Brendan McKay's nauty program.) It seemed to offend the sensibilities of some folks in some fields to have people like Linus Pauling, if I recall the discussion correctly. Such people could still be linked to in the list, while having the flexibility of whether or not to mention his Erdos number in the bio, and if so, whether or not to link back to the list. There will be some people for whome the only possibility of linking back to the list will be a wikilink from the sentence of the article (for example, it seeems doubtful that an Erdos number field will be added to the Politician infobox, so Ahmed Chalabi will have to settle for being in the Erdos number 6 list, and having a sentence in his bio.) --Ramsey2006 01:26, 15 November 2007 (UTC)

It seems to me that those people are still, you know, mathematicians. I mean, if a it looks like a mathematician, acts like a mathematician, etc, it must be a mathematician. Ron Graham may have an appointment as something with a not-so-pure math title, but he (and the others) are linked to Erdős by way of combinatorics - the work of mathematicians. --Cheeser1

I definitely think of Brendan McKay as a mathematician, and so does he: "I am a mathematician" is how his user page starts. We have also placed the article page in several maths categories.  --Lambiam 09:30, 15 November 2007 (UTC)

Simply as a personal note — I don't really expect anyone to be swayed by this — I hate infoboxes. They reinforce the notion that a complex thing (in this case a person) can be encapsulated by a neat box with a small number of fields, like a baseball card. Paul August ☎ 02:57, 15 November 2007 (UTC)

Well, how about a little itsy bitsy teeny weeny Erdos number infobox with just a single field? Wouldn't look like a baseball card, and would just take up a little bit of real estate in the upper right hand corner of a bio. Are there any precidents on wikipedia for something like that? --Ramsey2006 04:29, 15 November 2007 (UTC)

Something like Template:Coor title dms? —David Eppstein 04:36, 15 November 2007 (UTC)

Works for me. --Ramsey2006 05:01, 15 November 2007 (UTC)

I think Erdős numbers are not so important that they need to be mentioned at the top of the article, either in a template like Template:Coor title dms or in an infobox above the table of contents. I have no problems with an infobox further down, and by all means make a list. -- Jitse Niesen (talk) 13:59, 15 November 2007 (UTC)

Further down seems appropriate to me. --Ramsey2006 16:32, 15 November 2007 (UTC)

Is Wiki a Database?

Part of the recent controversy regarding the Erdos Number Categories seems to be philosophical disagreement about what constitutes good encocylopedia material. BHG, an admin who led the opposition, has formulated some of that philosophy at Not a Database in WikiTalk. The piece enunciates some of the things we heard in the debate, e.g. "the category must define the subject of the article". In comparing-- and contrasting-- the Wiki to a relational database, BHG presents some of their PoV in a manner that might be comprehensible to us. (That in itself is comendable.) I invite concerned parties to read it and comment. If we're going to play together in the sandbox we need to have some common language. Thanks, Pete St.John (talk) 17:39, 19 November 2007 (UTC)

By the way, her admin status is I think irrelevant in this debate — she took no action that could not have been taken by any other user, and when not taking administrative action admins are not given any precedence over non-admins. —David Eppstein (talk) 18:08, 19 November 2007 (UTC)

It might have been more pointed to say "an experienced, influential editor" instead of "admin". The point is that she proposes new wording for wiki policy/guidelines, which are somewhat more worth reading because of notable things about their author: she's influential, she led the movement to delete the categories. And she's taking the trouble to enunciate an editorial philosophy that some of us (e.g. me) have had a difficult time understanding.

However, I think her admin status is relevant in se. I believe (it's only a theory) that the editorial philosophy she espouses (with the indicated items, and in the deletion debates) is more in accord with an admin demographic, than with a mathematics contributors demographic or even an editors demographic. So for example, the opinion counts were all overwhelmingly (2-1 up to 3-1) in favor of "keep" (the categories) or "oveturn" (the deletion), over the what 3 CfD's and 2 Deletion Reviews, whatever, but the administrative actions consequent to those debates favored the opposition (they deleted the category, admin Kbdank71; sustained the deletion, admin Xoloz). Pete St.John (talk) 19:18, 19 November 2007 (UTC)

New list

With the categories decisively gone, I have created List of people by Erdős number. Ntsimp (talk) 18:54, 24 November 2007 (UTC)

The collaboration calculator Collaboration Distance is amazing. It calculated my Erdös number (4 via James C. Owings Jr., Dilip B. Madan, and Robert W. Robinson) in less than one second. But contrary to what it says, I had to give my name in the form "Spriggs, James" (full first name rather than initial). JRSpriggs (talk) 08:39, 25 November 2007 (UTC)

Commutative diagrams

I wanted to make some commutative diagrams (in the context of pin groups and related topics), and couldn't find any documentation; people seem to make them in many ways. I figured out how to make SVG commutative diagrams, so that it's now quite easy, and documented it at: meta:Help:Displaying a formula#Commutative_diagrams.

Hope this helps!

Nbarth (talk) 22:33, 25 November 2007 (UTC)

Dessins d'enfants

I just finished a major expansion of dessin d'enfant. I'd appreciate it if some people who know more than I about Riemann surfaces and algebraic number theory (not difficult!) could take a look and make sure I haven't said something stupid. Edits or general feedback on readability, content, etc., would be welcome, too, of course. PS: As a deliberate stylistic decision, I tried to follow Gowers' advice to put examples first [10] [11] — I'd also appreciate feedback on how well that worked. —David Eppstein (talk) 04:46, 26 November 2007 (UTC)

Template:Proof

I just noticed that Template:Proof was deleted, with almost no discussion, and certainly without a single mathematician participating in the debate. You may recall that the function of this template was to handle the job of the controversial notion of math articles with non-notable proofs of assertions therein (typically, non-notable or even pedestrian proofs found in textbooks). For some examples, see Category:Article proofs. After lengthly discussion, it was decided that such proofs don't really belong in article space, and yet perhaps its harmless to keep them around. Thus, the template served to mark thier status as being in purgatory, and attempted to explain why a purgatory exists.

Sadly, all this seemed to be quite lost on the foks who deleted the template.

I'm somewhat frustrated that a small band of "crazies", to quote KSmrq, can so quickly and easily damage positions arrived at through long and hard consensus debate. Isn't there something that can be done to limit this kind of damage? If *this* group, after effort and debate, got rid of the template and/or the proofs, that would be fine. But to find outsiders come in, misunderstand, trample, and decamp, I find that quite frustrating. linas (talk) 04:35, 26 November 2007 (UTC)

The text of the template was

This mathematics article is devoted entirely to providing mathematical proofs and support for claims and statements made in the article Kronecker's lemma. This article is currently an experimental vehicle to see how well we can provide proofs and details for a math article without cluttering up the main article itself. See for some current discussion. This article is "experimental" in the sense that it is a test of one way we may be able to incorporate more detailed proofs in Wikipedia.

Affected articles can be seen in Woohookitty contributions.

I can see some would question the wording, which seem over wordy and apologetic. The experiment part is odd, can we say whether the experiment is over and was it a success or failure?

There were some good points in the debate:

• • Would a better name for Kronecker's lemma/Proof be Proof of Kronecker's lemma
  • Would {{seemain}} be just as good.

It also raises the question of do we still need Category:Article proofs?

As for the small band of "crazies" the solution is vigilance. Categories and templates are problematic as they are used by many places but few edit them so they don't appear on watchlists. Luckly we have Wikipedia:WikiProject Mathematics/Current activity which I believe lists categories and templates on XfD.

Above all keep cool. If a better wording can be found we can take this to Deletion Review. --Salix alba (talk) 09:57, 26 November 2007 (UTC)

Yes, this is easily fixed: if the template is useful, then it can be undeleted or recreated. As for the /Proof and /Proofs idea, my view is the following: if the proof is notable enough, then it should be presented at a page like Proof of Kronecker's lemma. If it is not notable enough, then it should be on a page like Talk:Kronecker's lemma/Proof. Subpages are disabled in the main article space, so Kronecker's lemma/Proof is actually an independent article which happens to have a slash in the title. In short: if it isn't notable enough for article space, it shouldn't be in article space. Geometry guy 10:26, 26 November 2007 (UTC)

I've just added {{seemain}} and Category:Article proofs to all the articles this appeared in. Aside from the wording the template placed the articles in the category, linked to mathematical proof so it was functionally useful. I've also slightly changed the wording of Category:Article proofs to remove reference to the template but the same experimental wording still remains there. The quality of the proof articles is very variable, some are just a few equations leading to the proof others are better with discussion and references. --Salix alba (talk) 11:11, 26 November 2007 (UTC)

Please see the debate in Wikipedia:WikiProject_Mathematics/Proofs, or at least skim it; and don't neglect to look at the archived debate as well. The primary problems are these:

• There is no consensus that these things even belong in article space, which is why "ArticleName/Proofs" is used, instead of "Proof of Article Name".
• Most or all of these are of very low quality. They are unreferenced, and written in an ad-hoc manner. They cannot stand on thier own two feet, which is why the consensus was "keep them out of article space".

Myself, I'm undecided. I like the core concept that "theorems should have proofs". Actually providing such proofs in WP presents some serious operational challanges, such as the standard-of-quaility, referencing, and vigilance issues. We do not currently have any standards or guidelines in place by which article proofs can be judged to be good or bad, adequate or inadequate. linas (talk) 14:32, 26 November 2007 (UTC)

Thanks, I refreshed my memory about this discussion. The problem is that "ArticleName/Proofs" is in article space. For better or worse, it isn't even a subpage of "ArticleName": it is a separate article with a slash in the title. Therefore it is just as open to deletion as any other article, and I don't think the current "/Proofs" articles would fare very well at AfD. If you want to "keep them out of article space", they need to moved somewhere else, e.g. "Talk:ArticleName/Proofs" or "Wikipedia:WikiProject Mathematics/ArticleName/Proofs". Geometry guy 18:15, 26 November 2007 (UTC)

I'm sure everyone can agree that in mathematics, theorems have proofs. The issue of which proofs to include on Wikipedia is a different matter. Like linas, I find many of the proofs that are included here to be particularly bad. I think it's reasonable to include a proof when it is short, stands mostly alone, and conveys useful knowledge to the reader beyond just proving the theorem. But most proofs should be left to texts where there is space and editorial freedom to write them properly. — Carl (CBM · talk) 14:50, 26 November 2007 (UTC)

There is a wikibook that is dedicated to all kinds of mathematical proofs, so please put them there if you have one! Paxinum (talk) 15:19, 26 November 2007 (UTC)

I concur - not every theorem needs a proof. I feel like Ramsey's theorem (for example) is a place where a proof is fairly concise and quite helpful. The fundamental theorem of arithmetic is another. However, Fermat's last theorem or four color theorem would be bad places for a proofs (exaggerated examples, I know). I'm not sure if we can agree on a precise standard, but it's certainly a point we should consider (if nothing else) on a case by case basis. How does this proof add to the article? and Is this proof well-known, well-referenced, and easy to read/follow? seem like relevant questions. --Cheeser1 (talk) 16:10, 26 November 2007 (UTC)

User:CBM wrote:

I think it's reasonable to include a proof when it is short, stands mostly alone, and conveys useful knowledge to the reader beyond just proving the theorem. But most proofs should be left to texts where there is space and

That statement might seem like a grudging admission that, gee, maybe some proofs are good enough to be barely allowed into polite society...
However, some proofs are of far greater interest than the bare fact being proved, especially when the technique of proof is the brilliant, or in some cases at least exceptionally clever, insight involved (e.g. Cantor's diagonal argument, Cantor's back-and-forth method, proof that π is irrational, proof that 22 over 7 exceeds π, Archimedes' use of infinitesimals), or the statement is one of those simple things in number theory that any 9th-grader can understand in an instant but the proof of the statement, on the other hand, is a major intellectual breakthrough or at least a substantial enough achievement to be widely known among mathematicians (e.g. Fermat's last theorem, Brun's theorem). Michael Hardy (talk) 17:03, 26 November 2007 (UTC)

I agree - I have spent time working with proofs and proof sketches in articles including Halting problem, Diagonal lemma, Gödel's incompleteness theorems, Kleene's recursion theorem and others. I am very sensitive to whether something is called a proof or a proof sketch.

I do think that, unlike in a rigorous mathematical text, it is often appropriate on Wikipedia to simply state a fact, with no mention of proof. If the fact is sufficiently interesting or esoteric, a reference to a published proof may be appropriate. But it isn't necessary to make an attempt to justify every single fact in each article. Our goal is to condense and summarize large parts of mathematics in a form that is accessible to a broad audience, not to create a rigorous text of all existing mathematics. — Carl (CBM · talk) 17:53, 26 November 2007 (UTC)

If I understand correctly, Michael Hardy refers to cases where a proof itself is an interesting object, which deserves encyclopedic mention irrespective of the importance, or lack of same, of the fact proved. For example, the proof of the four-color theorem deserves a discussion in Wikipedia because of the controversy over the status of computer-assisted proofs that it sparked, even if one were to argue that it is unimportant whether planar graphs can be 4-colored. We cannot reproduce the proof itself in Wikipedia, but we can still discuss it without doing so. We can speak about interesting aspects of a (full) proof even if we cannot include more than a sketch of the proof we speak about (or perhaps not even that, as with the four-color theorem). –Henning Makholm 22:52, 27 November 2007 (UTC)

Atropos has essentially apologised on my talk page for not realising that the template had a useful function. If a reworded template would be helpful, I'd be happy to undelete the old one to provide a starting point and preserve the edit history. Geometry guy 19:39, 27 November 2007 (UTC)

Index lists - RfC

Wikipedia:Village pump (policy)#Index lists is a complex issue which I've tried to summarize. It concerns pages in mainspace like List of timelines, Lists of mathematics topics, and List of film topics. Its scope is currently a few hundred pages, and potentially a few thousand pages. Feedback would be appreciated. -- Quiddity (talk) 19:14, 26 November 2007 (UTC)

'This issue may be important to Wikipedia's mathematics community. The magnificent lists (plural, "lists"; not "list") of mathematics topics, an officially Featured List, could get moved from the article space into the portal space. I don't think it should be there. It is not just a way of navigating among Wikipedia articles; it is a way of browsing the subject matter itself. Michael Hardy (talk) 21:21, 26 November 2007 (UTC)

Count

I randomly clicked on Wikipedia:WikiProject Mathematics/Count today and found a rather round number. Of course we all know that divisibility by 1000 is no big deal, but it makes a good excuse to celebrate the good work by many contributors over many years to create so many mathematics articles. Geometry guy 22:42, 26 November 2007 (UTC)

;-) Paul August ☎ 22:49, 26 November 2007 (UTC)

What is this counting? Is it the number of contributors to articles in the "mathematics" categories? Or to this discussion page? Or the number of articles at list of mathematics articles? Michael Hardy (talk) 23:27, 26 November 2007 (UTC)

I think it is the number of articles at list of mathematics articles, but I'm sure Jitse or Oleg will correct me if I am wrong. Note that the count changes once per day, usually by an integer bigger than one, so it was a bit of luck to hit a round number, hence the post. Geometry guy 23:38, 26 November 2007 (UTC)

I think it is the number of mathematics and mathematicians articles (the total, that is). Jitse should know for sure. Oleg Alexandrov (talk) 07:39, 27 November 2007 (UTC)

Yep. -- Jitse Niesen (talk) 11:49, 27 November 2007 (UTC)

Where do I mention math-related stuff about to be deleted?

I notice that all the space on WP:MATH front page is devoted to FA- and A-class articles or similar, but nowhere is there an area (or link to an area) where articles/other pages undergoing AfD or similar deletion discussion can be listed. :-(

That said I nominated a mathematician and physician of unknown notability, James M. McCanney, for deletion. AfD is here. Might not be widely-published as he's said to be "anti-establishment". Just a heads up. Pegasus «C¦T» 07:23, 27 November 2007 (UTC)

Mentioning it here is fine, but if it has a sufficiently mathematical category it will also show up automatically in Wikipedia:WikiProject Mathematics/Current activity. —David Eppstein (talk) 07:34, 27 November 2007 (UTC)

Thanks for your quick reply! Pegasus «C¦T» 08:19, 27 November 2007 (UTC)

WP:AFD on Error-correcting codes with feedback

Error-correcting codes with feedback has been nominated for deletion, see Wikipedia:Articles for deletion/Error-correcting codes with feedback 132.205.99.122 (talk) 23:05, 29 November 2007 (UTC)

Core Contest

I guess folks have seen the Wikipedia:The Core Contest which is offering a $100 prize for the most improved core topic. Constant as well a quite a few of our basic articles in on the list. It could be a good time to foucs on improving one of these. --Salix alba (talk) 23:19, 30 November 2007 (UTC)

I hadn't looked at it. Have the key articles on the list been selected for being known to be in need of improvement, or is it a list of the most important articles, regardless of quality? It wouldn't hurt if we had a list of articles dealing with basic topics important to mathematics that are in dire need of improvement. I'd like to nominate Definition.  --Lambiam 10:03, 1 December 2007 (U

Equivalence symbol

Is anyone here familiar with the "equivalence symbol" used in the last row of this table? [12] It looks like an equals sign with a caret on top. I've never seen it anywhere else. Should it be mentioned somewhere on Wikipedia, such as in the equals sign article? --Itub (talk) 07:28, 30 November 2007 (UTC)

I know from experience that the symbol is in widespread use in some (probably all) German schools. I don't think there is an exact meaning; at least in school it's certainly not used in the restricted technical sense described in your source. Our teachers pronounced it as "entspricht", i.e. "corresponds to", and I think I can remember an instance when a chemistry teacher used it when explaining the rule of three. I think basically it's just a kind of general purpose "equality with a disclaimer" symbol with no clear meaning. IIRC, among the teachers who actually wrote equations the mathematics teachers were least likely to use the symbol, and the geography teachers used it most. --Hans Adler (talk) 09:48, 30 November 2007 (UTC)

There are two similar but distinct Unicode symbols: ≘ (U+2258 CORRESPONDS TO) and ≙ (U+2259 ESTIMATES). The former, with a "frown" over the equals sign, is documented in equals sign as meaning "corresponds to", without further explanation. The symbol ≙ ("wedgeq") redirects to Correspondence (mathematics), but is not explained or even used in that article. I think this is a mistake; the first symbol should have been used instead. The second, with a wedge, is documented in the German Wikipedia as meaning "is estimated as" (see Gleichheitszeichen.) I think it may be in use as a poor man's substitute for the "frowneq". I have also seen it used as a poor man's alternative to ≜ ($\triangleq$, "triangleq", U+225C DELTA EQUAL TO) meaning "is defined as", as used, for example, in the article Ball (mathematics). See also Wikipedia talk:WikiProject Mathematics/Archive 19#Convention for definitions: Use := or \equiv?. I'm in favour of documenting all of these properly, but do not have any authoritative sources.  --Lambiam 12:58, 30 November 2007 (UTC)

As has been discussed at length before, I support the use of a simple equals sign in our articles, with accompanying English, rather than a multitude of decorated symbols. An article documenting the common uses of various symbols would be reasonable, although finding a source might indeed be difficult. — Carl (CBM · talk) 13:09, 30 November 2007 (UTC)

proposed deletion

See Wikipedia:Articles for deletion/Error-correcting codes with feedback.

Normally I would expect this to get listed at Wikipedia:WikiProject Mathematics/Current activity. But it hasn't. It bore the "Information theory" category. Apparently articles with that category don't show up on the current activity page. I've added the "Mathematics" category for now.

Oleg, are you the person who manages the software that determines which things show up on the "current activity" page? Can you do something about this? Michael Hardy 23:17, 1 December 2007 (UTC)

Logical necessity of inconsistency

Logical necessity of inconsistency has been listed on AfD. —Ruud 23:41, 1 December 2007 (UTC)

Srinivasa Ramanujan

Someone here said the integral at Srinivasa_Ramanujan#Contacting_English_mathematicians is incorrect. Could anyone look into this? Also, I would appreciate if some editors could verify the other mathematical statements in LaTeX. I don't think I messed up anywhere when I wrote those bits a few months ago, but I'd appreciate some confirmation in any case. Thanks in advance, Nishkid64 (talk) 03:24, 2 December 2007 (UTC)

It is certainly true that the integral in the formula diverges, since the integrand does not approach zero as x approaches infinity.

$\int _{0}^{\infty }{\cfrac {1+\left({\cfrac {x}{b+1}}\right)^{2}}{1+\left({\cfrac {x}{a}}\right)^{2}}}{\cfrac {1+\left({\cfrac {x}{b+2}}\right)^{2}}{1+\left({\cfrac {x}{a+1}}\right)^{2}}}\;\;dx={\frac {1}{2^{\frac {\pi }{2}}}}{\frac {\Gamma (a+{\frac {1}{2}})\Gamma (b+1)\Gamma (b-a+{\frac {1}{2}})}{\Gamma (a)\Gamma (b+{\frac {1}{2}})\Gamma (b-a+1)}}.$

Those factors of 1 seem rather weirdly placed. --Ramsey2006 04:05, 2 December 2007 (UTC)

Okay. I'll look into the book and check the mistake. R.e.b has fixed the formatting here. Nishkid64 (talk) 04:51, 2 December 2007 (UTC)

Nevermind. R.e.b.'s changes seem to have fixed the integral. Nishkid64 (talk) 05:19, 2 December 2007 (UTC)