Wikipedia talk:WikiProject Mathematics/Archive/2005/Nov-Dec

message: Since the purpose of the article originally started by StuRat was in part didactic, how about farming it out as a wikibook?  There is still the historical question of the relation of Boole's algebra to the different entity called Boolean algebra to be sorted out, and yet another new article housed at BL might be the best place to do this.  The new article can then comment on the non-mathematical aspects of cultural usage that originalyy prompted StuRat to write his text, and the genuinely encyclopediac contribution of the BL article can still be accomodated in the BA article. --- Charles Stewart 18:57, 1 November 2005 (UTC)
replies: text: I have no objection to there being a WikiBook on either, or both, the current Boolean logic content and the current Boolean algebra content.  However, if this is to be used as a justification for deleting either article, in whole or in part, from WikiPedia, I am strongly opposed to that.  StuRat 19:07, 1 November 2005 (UTC)
replies: text: The new article would not be based on your article, but it would be non-PhD-level and it would document what non-algebraists get out of the mathematics.  I don't think that a compelling case for en.wikipedia to host an introduction to BAs for people who don't want to learn algebra has ever been made, if that is the deletion that my proposal makes that you object to. --- Charles Stewart 19:11, 1 November 2005 (UTC)
replies: text: The basics of set theory are taught well before algebra in school.  For example, an episode of the PBS kids (ages 7-11) math show Cyberchase contained an introduction to set theory including Venn diagrams.  Any assumption that elementary set theory, and the Boolean logic operations based on it, requires advanced algebra, is therefore faulty. StuRat 19:40, 1 November 2005 (UTC)

text: I don't see the relevance of your remark to mine. --- Charles Stewart 20:17, 1 November 2005 (UTC)
replies: text: I was responding to the statement "I don't think that a compelling case for en.wikipedia to host an introduction to BAs for people who don't want to learn algebra has ever been made...", which seems to be saying that a knowledge of algebra should be required to understand the introduction sections.  My point is that the introductory level material can be made without the use of algebra, and that such material can be added later. StuRat 20:55, 1 November 2005 (UTC)

text: I made no such claim.  WP articles on topics of broad interest should be accessible, even if the article should contain material that is not generally accessible.  Wikibooks is the place for tutorials, see WP:NOT, point 8 of Wikipedia is not an indiscriminate collection of information, which is what "an introduction to BAs for people who don't want to learn algebra" would be.  What is at stake in hosting such an introduction here rather than there?  I see no point of principle at play here besides the one about following policy.  --- Charles Stewart 15:38, 2 November 2005 (UTC)
replies: text: Your statement that "WP articles on topics of broad interest should be accessible..." seems to imply that you don't think that we should have the goal of making all articles accessible.  I disagree, and think that all articles should be made accessible to the broadest audience possible. Removing info from Wikipedia makes it considerable less likely to be found and thus less accessible. StuRat 15:56, 2 November 2005 (UTC)

text: I believe that there are articles for which it is not very important to spend much time thinking about the general reader, but instead most effort should be directed at the specialist.  As you are aware, I've been citing analytic continuation as an example of this for some time.  --- Charles Stewart 19:12, 2 November 2005 (UTC)

text: Are you disputing the policy?  Are you aware that both WP and Wikibooks are both hosted by and reflect the values of the Wikimedia Foundation? --- Charles Stewart 19:12, 2 November 2005 (UTC)
replies: text: I believe MarSch means the same thing as me, that while adding a WikiBook on any topic is a worthy goal, to use that as a justification for deleting material from WikiPedia, if that is your intent, is not at all helpful. StuRat 20:00, 2 November 2005 (UTC)
thread_title: Wikibook proposal

message: See Talk:Mathematical analysis#Mathematical.2FReal Analysis. A fellow is having problems with the modern defintion of real numbers (among other things). He/she says "infinitesimals exist". My reply would be that the real numbers are defined by axioms, and it follows from those axioms that there are no infinitesimals. It would be good however to have more in-depth comments than that on that talk page.  Oleg Alexandrov (talk) 11:22, 29 October 2005 (UTC)
replies: text: I would take the reals to be defined in terms of other things rather than axiomatized, but the answer comes out the same: "this is what we're talking about; talk about whatever you like, but don't call it the reals". At a cursory glance it looks like you're arguing with a crank over there. The best way to do that is not to; since he seems to have given up, I'd just let it go. --Trovatore 19:49, 1 November 2005 (UTC)
replies: text: Infinitessimals exist, John Conway does a marvelous and fun construction in "On Numbers and Games". Although they exist in between real numbers, they're not exactly "numbers" themselves, though. I've always wondered if its possible to do some sort of calculus with them, e.g. treat them as some sort of fiber bundle or something over the reals, and get something other than trivial results.  No idea.  linas 16:04, 3 November 2005 (UTC)
replies: text: WHat about non-standard analysis? --MarSch 16:57, 3 November 2005 (UTC)

text: and Non-standard calculus? --MarSch 17:06, 3 November 2005 (UTC)
replies: text: J.H. Conway's surreals and NSA's hyperreals are both interesting structures (or classes of structures in the case of the hyperreals; there are nonisomorphic structures that fit the description). But they aren't the reals. Considerations involving them may tell us things about the reals, but they aren't the reals. Sorry to use baby talk; I imagine that both of you know these things--I'm just listing the points that can't be fudged when presenting the material to naive readers, or when having a discussion with a crank (if the latter is adjudged necessary). --Trovatore 17:10, 3 November 2005 (UTC)
replies: text:  The infinitesimals are not real, and they are not imaginary either. Gosh, what's left then? Oleg Alexandrov (talk) 17:45, 3 November 2005 (UTC)
replies: text:  My professor in introductory calculus would occasionally refer to indeterminate forms, infinities, and infinitesimals as "Christmas trees". Actually quite a good way to stop you from carelessly using them as regular numbers. Fredrik | talk 18:01, 3 November 2005 (UTC)

text:  It's worth amplifying on non-standard analysis, though I think the original discussion was at a much lower level of sophistication. Suppose we lay out a system of axioms for the reals, then look around for possible models that satisfy those axioms. A standard model includes just what we expect and no more. A non-standard model — which supports the same set of theorems — can exist and have extra goodies like infinities and infinitesimals. To put the extra goodies to work requires careful distinctions. Another tactic is to use topos theory and the different logics that allows. In this way we get a somewhat different version of infinitesimals such as those discussed in smooth infinitesimal analysis  (PDF). A limited number of mathematicians enjoy these foundational games; many more seem to take the attitude "go away, we're trying to get work done here". But then, I remember hearing some insist that category theory was a waste of time, on the one hand; and I've seen topos logic  (PDF)   put to serious work in the semantics of programming languages, on the other hand. I feel it's a delicate topic, because while I'm in the camp that enjoys foundational explorations, I'm painfully aware that most of the people who raise questions on Wikipedia about infinities and infinitesimals are clueless cranks. Too often the cranks are able to get some leverage because of loose writing, acceptable for informal mathematical discussion but not careful enough to stave off false interpretations. It's a difficult discipline, should one choose to accept it. For thousands of years mathematics progressed with stronger intuition than foundation, and I suspect that even though we're taught we should respect foundations today, many still just pay lip service. And for good reason: if we have to dot every "i" and cross every "t" any time we speak, we'll be tongue-tied. --KSmrqT 20:31, 3 November 2005 (UTC)
thread_title:  Issues with the real numbers 

message: During the travails of my spellbot, I got the following comment:
:It turns out that both "parameterize" and "parametrize" (the bot's spelling) are very common; M-W lists both. I learned the first version somewhere back in the mists of time and only found out just now of this variant. I was actually surprised to see that in many of my books also use the second version, and I never noticed... (incidentally the bot also corrected a "parameterise" to "parametrise", too. Yay for bots that also know British spelling :-) Choni 13:06, 29 October 2005 (UTC)
replies: text: I am only familiar with the former version.  It seems more natural, being closer to the root word, as well. StuRat 23:55, 31 October 2005 (UTC)

text: American Heritage seems happy with both, nodding slightly towards including the "e". That agrees with my practice when writing or proofreading: either is fine. It might be nice if an article was at least self-consistent, but frankly I doubt many readers would notice. In contrast, "parametric" does not allow an extra "e". --KSmrqT 00:11, 1 November 2005 (UTC)
replies: text:  Of the four permutations, the only one that looks really wrong to me is "parametrise". I think british and american speakers actually pronounce the word slightly differently. (I'm an Australian speaker.) Reminds me of aluminium vs aluminum. Dmharvey  Talk 00:14, 1 November 2005 (UTC)
replies: text: I think aluminium is what is used in most languages. Therefore I prefer to use it also in English. --MarSch 12:45, 1 November 2005 (UTC)

text: The situation is a bit different, because in the case of Aluminium, there is actually an international standard that specifies the official name as "Aluminium", and not "Aluminum".  See for example IUPAC Periodic Table of the Elements, which says: '“Aluminum” and “cesium” are commonly used alternative spellings for “aluminium” and “caesium.”'.   As an American, I find this annoying, but that's the way it goes. -- Dominus 15:49, 1 November 2005 (UTC)
replies: text: Hey that's good :) Now we only need to get rid of potassium and call it Kalium instead.--MarSch 17:07, 1 November 2005 (UTC)
replies: text: Sure, but then we need to find a way to extract it from kale, instead of potash. 17:58, 1 November 2005 (UTC)

text: Americans don't get annoyed; we effect regime change. I can say that now that I'm in Canada. Then again the Canadians might not know I'm joking. --Trovatore 20:28, 1 November 2005 (UTC)
replies: text: Yea, you might get kicked "oot". StuRat 20:46, 1 November 2005 (UTC)
replies: text: Let's get back on task, eh? For what it's worth, I've met people (including myself) who insist it should be spelled "parametrize" (or "parametrise" if you live across the pond). I'm not sure how often I've run into the latter, though. - Gauge 03:45, 10 November 2005 (UTC)
thread_title:  Parameterize 

message: The Hilbert problems page is seeing some development, which is only right and proper. It is also raising numerous issues, in respect of what a 'solved' problem is. This is an opportunity, to do better than other Web treatments (few of the historians really have all the background to write with authority on all 23). The words 'worms', 'can' and 'of' come to mind.
I wonder whether the laudable effort to get a table summary of it all on the page hasn't had its day. It is hard to write enough in a table entry, since some of the problems have several 'ply' in them. I also think that where Hilbert's n-th problem is now a redirect, we really need to have the buffer of a separate page. For example, Hilbert's fifth problem used to redirect to Lie group, but it seems clearer not to have arguments about what a Lie group is, and what the Fifth Problem was, on the same page.
Please come and help. This page missed Featured Article status over the summer, but has already been much expanded. Charles Matthews 09:49, 3 November 2005 (UTC)
thread_title: Hilbert problems

message: See talk:rotation#Request for comment. Oleg Alexandrov (talk) 00:58, 6 November 2005 (UTC)
thread_title:  Help wanted at [[rotation]] 

message: If anyone's feeling energetic, I started an article on Proofs of quadratic reciprocity. Sadly, it was a bigger job than I foresaw, and I've had enough for now. It needs several things done to it; see Talk:Proofs of quadratic reciprocity for my opinion on this. Thanks! I should go back to writing blahtex and existing in the real world now... Dmharvey  Talk 03:11, 6 November 2005 (UTC)
replies: text: I've intervened to link to Gaussian period to use indirection on the quadratic field. IMO this can be an interesting page, but mainly to send the reader to other parts of the site. Charles Matthews 11:17, 6 November 2005 (UTC)
thread_title:  proofs of quadratic reciprocity 

message: Wikipedia:Categories for deletion/Log/2005 October 30 - the classification of academics needs a big clean-up. Please come and vote. Charles Matthews 11:56, 6 November 2005 (UTC)
thread_title: [[:Category:Professors]]

message: * 
Unfortunately, the automation makes it difficult to manually add articles such as this to the current activity list. Uncle G 00:53, 10 November 2005 (UTC)
thread_title:  Articles listed at AFD 

message: See the talk page.  Has anyone else heard of this, outside of MathWorld? Arthur Rubin (talk) 01:14, 10 November 2005 (UTC)
replies: text: It would seem more logical to me to call this thing NXOR, per the suggestion at the talk page. XOR is probably a more familiar operation than NOR, and it is much easier to figure out what NXOR means: XOR goes 1 only on different inputs, so NXOR must go 1 only on the equal inputs. With XNOR one would probably have to draw a truth table. I checked that it is also equivalent to XAND, but people probably aren't used to working with XAND (I wasn't until I thought about it a bit). - Gauge 04:23, 10 November 2005 (UTC)
replies: text: If it is true only on the same inputs (both true or both false), wouldn't the simplest and most logical name be SAME ? StuRat 11:46, 10 November 2005 (UTC)
replies: text: I don't think we should use the name that seems simplest, but rather the name accepted in the mathematical community.  Anyway, my TI calculator says XNOR, not NXOR. -Lethe | Talk 14:31, 10 November 2005 (UTC)
replies: text: There are also far more Google hits for "logical SAME" than either "logical XNOR" or "logical NXOR", see the article's talk page for details.  I would say that this is evidence it is more accepted by the mathematical community.  Note that while "SAME" is a normal English phrase, "logical SAME" is not. StuRat 14:39, 10 November 2005 (UTC)
replies: text: Many of the google hits for "logical SAME" seem to be consecutive sentences the first of which ends in logical, while the second starts with same.  some seem to be grammatical errors for "logically same".  I see very few google hits for "logical SAME" which indicate that it is used as an operator in logic or CS.  I think your hit count is unreasonably high, given that you're searching two very common english words.  On the other hand, when you google xnor, every single hit is about the logical/CS operator.  Could you perhaps provide a textbook (or something more authoritative than google) that uses SAME for this operator, because I'm of the opinion that it's always called XNOR. -Lethe | Talk 16:09, 10 November 2005 (UTC)
replies: text: I will look for some.  Meanwhile, can we keep the discussion on the article's talk page ?  Having it in two places seems quite unnecessary. StuRat 17:01, 10 November 2005 (UTC)

text: I have a design that comprises 18 such gates open in another window as I write this.  xnor is what such a gate is called in Verilog. Uncle G 15:03, 10 November 2005 (UTC)
thread_title:  [[Exclusive nor]] 

message: see Wikipedia:Village pump (policy)/Archive O#Frustration with make technical articles accessible policy
Dmharvey  Talk 18:55, 11 November 2005 (UTC)
thread_title:  more on "article too technical" 

message: I want there to be either a list of categories or a category of categories here.  The more I think about it, the more I think it should be a list, not a category.  One reason is that some categories probably don't deserve their own articles.  Another is that it might be neat if we could put the categories in a table and like list their properties (cartesian closed, concrete, abelian, monoidal, etc).  But then again, I've never liked (wp organizational) categories.  Anyway, I started a list, which is basically just me adding a whole bunch of categories to the short list that was already at category (mathematics), in my user space because I wasn't sure if it should be an article.  Have a look? -Lethe | Talk 06:10, 12 November 2005 (UTC)
replies: text: You mean like the category of small categories? (couldn't resist...) - Gauge 05:39, 13 November 2005 (UTC)

text: Having a list of categories (as in category theory) would be nice. However, I find the table at the link you mention intimidating. I have no idea of categories, that is just an esthetic observation; maybe the table is useful. Anyway, if you decide to make such a list, it is good to add it to the List of lists of mathematical topics and also categorize it in :Category:Mathematical lists. Oleg Alexandrov (talk) 17:23, 12 November 2005 (UTC)
replies: text:  If a programming metaphor will help, think of categories as an object-oriented approach to mathematics. (Hidden humor intended.) The idea is to approach structures through maps. For example, look not just at vector spaces, but also at linear transformations, the maps that preserve the structure. Look not just at groups, but also at group homomorphisms. In fact, category theory has found that the structures themselves (called objects) are less important that the maps (called arrows). We can give an arrow definition of "product", say, that applies identically to any kind of category. (Example: an individual poset is automatically a category, with an arrow A→B meaning A≤B; its products are greatest lower bounds.) By the same reasoning, we study category-to-category maps (called functors), such as the forgetful functor that maps a vector space to the additive group of its vectors. We also consider functor-to-functor maps (natural transformations). By adding additional axioms we isolate categories (called topoi) that can replace sets as a foundation for all of mathematics. A table of categories (hint: good name) has the potential to organize diverse topics in a way that reveals common patterns. Category thinking has already had a broad and subtle influence on mathematics. (Warning: POV ahead!) In much the same way as lesser beings see groups and vector spaces everywhere, higher beings see categories. ;-) --KSmrqT 13:31, 13 November 2005 (UTC)

text: I think both a list and a category are appropriate. However the category name needs some thought, because it seems unavoidable that it will use the word "category" in two quite distinct senses in one short phrase. For example :Category:Mathematical categories isn't good, because it looks like it should be a collection of all subcats of :Category:Mathematics.  The only things I can think of that are clear sound a little like jokes (e.g. :Category:Category-theoretic categories. Actually maybe that one's not bad; once you get over the sound of it, it pretty much covers what needs to be covered. --Trovatore 17:29, 12 November 2005 (UTC)
replies: text: As regards the list, please note that there is already a List of category theory topics, and it includes a section that has some of the function of Lethe's new list. The lists should be coordinated in some way: The new list could be merged into the old one; the now-redundant part of the old one could be removed, with a link to the new one;  or minimally, there could just be dab-style notices at the top of both. The name List of categories suffers from the same linguistic problem mentioned in my last intervention. Could be List of category-theoretic categories. --Trovatore 17:47, 12 November 2005 (UTC)
replies: text: I took your suggestion on the name of a category.  I went ahead and created the category.  I probably will move the list into article space at some point as well. -Lethe | Talk 18:21, 13 November 2005 (UTC)
replies: text: Cool. I've made it a subcat of :Category:Category theory, and removed that now-redundant category from the articles in both. --Trovatore 19:17, 13 November 2005 (UTC)
replies: text: What's a pipe category? -Lethe | Talk 00:34, 14 November 2005 (UTC)
replies: text: (Think think think.) Sorry, no clever answer for such a promising straight line. When my edit summary says "pipe cat" it means that I pipe the category to a different name. Otherwise the whole category would be under the letter "C". It doesn't affect how the article name is displayed in the category listing, just how it's alphabetized. --Trovatore 00:38, 14 November 2005 (UTC)

text: I did notice the list of categories under the 'C' heading of :Category:Category theory.  I didn't see that other list.  Thanks. -Lethe | Talk 17:59, 12 November 2005 (UTC)
thread_title:  a list or a category of categories 

message: Wikisource is currently contemplating deleting all mathematical and astronomical tables (including expansions of transcendental numbers, tables of logarithms, ephemerides, and so forth) and all source code.  See Wikisource talk:What Wikisource includes for the discussion of this. Uncle G 15:49, 13 November 2005 (UTC)
thread_title:  Wikisource wants to delete all source and data 

message: I got confused the other day when I saw unitary in the context of a C*-algebra.  Eventually I figured out that it means "having multiplicative identity", and I changed it to unital.  I now see that some authors do use unitary in this sense (Hungerford), though it isn't mentioned in our page on unitary.  I'm going to add a mention there, but I kind of also want to change all instances I come across to unital, which is less ambiguous.  How do you feel about the word unitary to mean having identity in an algebra, or over a ring with identity for a module?  -Lethe | Talk 16:01, 13 November 2005 (UTC)
replies: text: I prefer "unital". I've never heard "unitary" being used to describe these things, and C*-algebras make a good case for avoiding confusion and keeping the terminology consistent. - Gauge 20:16, 13 November 2005 (UTC)
thread_title:  unitary versus unital 

message: One person uses multiple account to change the spelling of math articles one way or another. I reverted whatever I saw so far (that does classify as vandalism I would say, as that person was warned half a day before to not do that). I guess we need to take a close look at the recent changes to math articles from the list of mathematical topics to watch for more. Note that the person in question makes sure that the user page and talk page are blue, I guess to mislead people. Oleg Alexandrov (talk) 07:03, 14 November 2005 (UTC)
replies: text: Could you point us to some examples? I've noticed that from time to time I have to revert someone who changes "provably" to "probably" or "provable" to "probable", but I've never been quite sure whether that person is a vandal, or just doesn't understand either the meaning of the English words or the subject matter. --Trovatore 07:19, 14 November 2005 (UTC)
replies: text: Oleg is probably refering to User:Spellchecker, who is changing spelling from American to British English (example). I could live with that, British English being obviously superior, but this user is making the unforgivable mistake of using the widespread but terribly wrong -ise variant. :) Today, similar accounts have appeared, like User:Imperiul (example). Whoever it is, they must feel very strongly about it, making a new account just to change a single letter. -- Jitse Niesen (talk) 11:28, 14 November 2005 (UTC)
replies: text:  What examples? Yesterday I single-handedly (mouse-buttonly) repelled an entire attack of spelling clones, I expected to be awash in glory when I wake up in the morning, and instead you are asking for examples? Oleg Alexandrov (talk) 19:13, 14 November 2005 (UTC)

text: Well, there's a policy about this whole issue. Short version: If it's about a topic specific to one country/culture, use the appropriate version of English, otherwise use the one the article started with. I don't think we can allow such policies to be circumvented just because it seems like more trouble than it's worth. The matter should be explained to this user, and if he continues, there should be consequences. --Trovatore 16:29, 14 November 2005 (UTC)
replies: text: I follow the maxim "don't ascribe anything to malice which can be ascribed to ignorance".  I've seen cases where less common words were replaced by more common words which seem to fit in the sentence, and I assume those editors honestly thought they had found a typo.  When I revert back, I'm careful to describe the meaning of the word, so they are educated and don't try to "fix" it again.  It's a shame we can't somehow mark words with a "this is not a typo" flag, to prevent this mistake in the first place.  This reminds me of a problem IBM had in their user manuals...they contained blank pages at the end of chapters, but then people would call and complain that vital pages of their manual were blank, so they ended up printing "This page left intentionally blank" on those pages.  Ironically, printing that on them meant they were no longer blank, LOL. StuRat 04:07, 22 November 2005 (UTC)
replies: text:  That was repeated change of spelling after being repeatedly warned, and creating a lot of accounts to do that, presumably to hide his/her tracks. I would not say that person is evil, but you surely can't assume good faith here. Oleg Alexandrov (talk) 04:54, 22 November 2005 (UTC)
replies: text: I certainly don't mean to say that it's always an innocent mistake, just that it sometimes is. StuRat 05:04, 22 November 2005 (UTC)
thread_title:  Spelling vandal 

message: Expert fact-checking and other assistance requested at Inductive dimension. --Trovatore 07:25, 16 November 2005 (UTC)
thread_title: calling all topologists

message: Someone has proposed here that :Category:Dimension be renamed to :Category:Dimensions. Personally I disagree (though I'm open to argument). Please contribute (whether you agree with me or not). One possibility is that overly disparate concepts are being muddled together in this category. --Trovatore 19:00, 16 November 2005 (UTC)
replies: text: Not to start a big fight (and dimensional analysis cdould easily be made a subcategory), I'd say the Buckingham Pi theorem shows what that has to do with dimension (rank of an abelian group, whatever). Charles Matthews 09:54, 17 November 2005 (UTC)
thread_title: "Dimension" category up for renaming

message: Well known to whom? This seems a little silly. Dmharvey  Talk 03:18, 19 November 2005 (UTC)
replies: text: I agree. I put it on AfD. --Trovatore 03:52, 19 November 2005 (UTC)
thread_title:  [[List of well known mathematical formulas]] 

message: Hi, I'm not sure if this is the right place to put this, but I was wondering if there were any policies concerning examples on math pages? I dunno, but it seems that it might be useful if pages had some example problems (like if the Green's theorem page had an sample problem to find the area of a planar region, or whatever)... Thanks :-)--yoshi 00:59, 22 November 2005 (UTC)
replies: text: Examples are absolutely encouraged. Most people are just too lazy to provide them. I would say, though, that there's an appropriate level of detail to present in an example. It shouldn't be worked out like a homework assignment; just enough detail should be given to get the reader started on working it out. That's my own take; we'll see if others agree with me. --Trovatore 01:04, 22 November 2005 (UTC)

text: Oh, amend the above to "most people, including me, are usually too lazy...." I didn't mean that to come across as a criticism of the other editors in the project. --Trovatore 01:07, 22 November 2005 (UTC)
replies: text: haha :-) I think it would be nice to have some completely worked out problems (like sample homework problems)... but I guess I should just contribute some and see what others think. sorry kinda new to wiki stuff :-) --yoshi 01:14, 22 November 2005 (UTC)

text: Examples? Yes, please. An encyclopedia is probably not the right place to challenge a reader to "work it out". Use good judgment; examples may be stated without proof, or a proof may be included if it is short and instructive. Equally important, and omitted more often still, are counterexamples ("near misses"). For Green's theorem, say, a figure-8 curve might be used to show what can go wrong. Also, a good picture is worth ten thousand equations (for some topics and some readers). --KSmrqT 01:50, 22 November 2005 (UTC)
replies: text: I agree that it's not a place to "challenge a reader", but I think it's even less a place to present detailed solutions to exercises. Examples are great, but let's keep them reasonably brief. Nonexamples (cases where the method doesn't work, in this instance) are also useful, as you say. --Trovatore 01:57, 22 November 2005 (UTC)
replies: text:  Anybody writing an article without examples sins against the math style manual and his own soul. :) Oleg Alexandrov (talk) 02:07, 22 November 2005 (UTC)

text: I agree, examples are a capital idea !  I think the more thorough the better, as long as they aren't redundant with other examples.  Many readers who can't follow a purely theoretical discussion can easily follow it with a few examples.  For those who don't need the examples, they are easy to skip, especially if they are properly demarcated in their own sections.  Closely related to examples are applications - how this bit of math can be used to benefit mankind. StuRat 03:49, 22 November 2005 (UTC)
thread_title:  Examples? 

message: Your participation is appreciated... --- Charles Stewart 20:10, 23 November 2005 (UTC)
thread_title:  [[Wikipedia:Peer review/Logic/archive1]] 

message: The Wikipedia:Reference desk was not too long ago split into subjects.  Currently, there is a Wikipedia:Reference desk/Science subsection which is where math questions should go.  It seems to me that math questions are a pretty small fraction of the posts there, and most go unanswered (unless they're high school math questions).  How would you feel about having a separate place for math questions?  I like to ask questions, and I like to answer questions, so I would like it. -lethe talk 20:25, 23 November 2005 (UTC)
replies: text: If such a page existed, I would have it on my watchlist. Dmharvey 23:19, 23 November 2005 (UTC)

text: I would too. --- Charles Stewart 23:31, 23 November 2005 (UTC)

text: Same here, I support the addition of such a page. StuRat 00:32, 24 November 2005 (UTC)

text: I support this, although I may not have any time to answer questions. - Gauge 04:13, 18 December 2005 (UTC)

text: I am not very old on the project, so I don't know the level of questions that are posted, but I'll be willing to answer any that I can, and I too might have questions. So I support this. deeptrivia (talk) 04:19, 18 December 2005 (UTC)
thread_title:  math reference desk 

message: I've enjoyed editing WP so much that I've decided that it might be a good idea to organize my original-research thoughts, half-baked ideas, and full-fledged research results using a wiki, as opposed to trying to maintain a collection of half-finished LyX (TeX) documents (which is what I currently do, along with deep piles of paper).  I was about to install my own private copy of the mediawiki software on my server when it occurred to me that perhaps I should enquire here first...  Is there some public place where this could be done? I gather planetmath might be one-such, but I rather like the mediawiki interfaces.  I don't know if wikibooks allow original resarch; also, as I want to publish my personal notes, I want to exert considerable editorial control (i.e. deny write access by default, grant write access only to friends). 
The reason I find this interesting is the hyperlinking. Writing traditional, "flat", "linear" mathematics papers requires a review of basic concepts and notions early in the paper.  Using a wiki allows these steps to be skipped, in favor of links. It also allows hyperconnections between related concepts: as sometimes, the difficulty of writing a math paper is figuring out how to lay out the ideas in linear order. So I think that playing with a wiki for pure research and pseudo (self-)publication might be a worthwhile experiment.  But where shall I experiment?  linas 17:37, 25 November 2005 (UTC)
replies: text: Wikicities has an inactive mathematics wiki at http://math.wikicities.com. If that one is too general, I'm sure a pure research wiki could be set up at Wikicities if requested. Doesn't solve the problem of write access though. - Fredrik | tc 18:02, 25 November 2005 (UTC)
thread_title:  Original research wiki 

message: User:CarlHewitt has created a new category, :Category:Mathematical model, which he's been populating with theories, not models. I've put it on CfD. Opinions solicited (as always, whether they agree with mine or not). --Trovatore 00:42, 26 November 2005 (UTC)
replies: text: Ummm... perhaps he's just using the term "model" in a broader sense than that used in logic? Dmharvey 00:56, 26 November 2005 (UTC)
replies: text: Possible in the abstract, but none of the articles with which he populated the category (Set theory, Peano axioms, Non-Euclidean geometry) fit any notion of model known to me, and the danger of confusion from calling them "models" is unacceptable in any case. --Trovatore 01:19, 26 November 2005 (UTC)
replies: text: See the discussion at Wikipedia:Categories_for_deletion/Log/2005_November_26.  Regards,--Carl Hewitt 18:25, 26 November 2005 (UTC)

text: Hewitt is conflating at least two different meanings of "model". This category is of dubious use. More useful is the existing category of scientific model, which he's going around removing .--CSTAR 20:15, 26 November 2005 (UTC)
replies: text: It has been proposed to create category :Category:Mathematical model (to go with the existing article Mathematical model) as a subcategory of :Category:Scientific modeling. CSTAR opposes this proposal. Regards,--Carl Hewitt 20:32, 26 November 2005 (UTC)
thread_title: Category:Mathematical model on CfD

message: Background: Due to the influence of Soare, in recent years it has been fashionable to use the term "computability theory" for what used to be called recursion theory. Very recently on WP, :Category:Computability was renamed to :Category:Theory of computation, where some of the articles are a good fit, but by no means all of them. Also the computability theory article underwent a substantial rewrite, focusing almost entirely on the aspects of interest to computer scientists rather than mathematical logicians.
This left a big void, as recursion theory or computability theory (as you prefer) is standardly considered one of the four branches of mathematical logic (the other three being set theory, model theory, and proof theory). So I created :Category:Recursion theory and a stub article at recursion theory.
What needs to happen now:
#A decision needs to be reached about whether this split is really correct, and if so, what are the criteria. The rough criterion I used to divide articles between the categories was whether I thought the topic would be studied by people who think of themselves as mathematical logicians, or people who think of themselves as computer scientists. A very substantial overlap remains. If the categories were to be remerged, though, it certainly couldn't be under the name "Theory of computation". If the articles were remerged, the new article would have to spend less time talking about Turing degree 0, to get to some real topics in recursion theory faster.
#Assuming the articles remain split, recursion theory needs to be enormously expanded.
#I was conservative in removing :Category:Theory of computation from articles. Someone who knows about theory of computation should go through the articles in the intersection of the two cats and say "That's not theory of computation" on some articles.
See the discussion at Talk:Computability theory (computation). --Trovatore 20:31, 26 November 2005 (UTC)
replies: text: I strongly believe these two categories should remain split. As this is important to both mathematicians and computer scientists their will always be one party who will get confused if we merged them. (E.g. computer scientist being not so very interested about thing with a Turing degree greater then 0, and mathematical logicians being not se very interested in thing with Turing degree 0. —R. Koot 16:32, 27 November 2005 (UTC)

text: A aplit here seems to make sense.  Computability theory should be the article called Computability theory (computation), with the reference at the top to recursion theory.  Though really the two are the same topic, its just that recursion theory more with nonphysical computational models.  Also, Computation should redirect to Computer, and a new article perhaps using some of the content from Computation should be at Theory of Computation, which would be a good overall starting point for the whole shebang.  Complexity theory is currently of pretty embarassing quality and needs to be rewritten.  I may do that at some point, though before I did I wanted to see how my Computability theory (computation) was recieved, and since I started that from a stub it seems less likely to be a problem.  --Readams 22:32, 28 November 2005 (UTC)
thread_title: Computability, recursion theory

message: I can't help noting that User:CSTAR has abandoned Wikipedia, or has gone into hiding, or is at least taking a wikivacation. It is hard for me not to conclude that this RfC and some of the personal attacks it engendered was the proverbial straw.  I enjoyed CSTAR's company, ad saw him as a good, highly qualified editor working in the general area of operator algebras and (surprise) C*-algebras.  Unfortunately, this meant that he was often involved in disputes fending off the latest cranky quantum mechanics edit, and I suspect this sapped a lot of his energy.  I am not happy about his departure, as he was a valuable and trusted editor. linas 22:05, 28 November 2005 (UTC)
replies: text: CSTAR was pretty much our only line of defense against the local variables agenda of Catherine Thompson.  Without him, we're lost.  What RfC are you referring to? -lethe talk 03:34, 29 November 2005 (UTC)
replies: text: I tried to follow a bunch of those links to see what happened, and I couldn't really follow the various threads.  Nor do I think I want to.  So I'll just say again that if crackpottism and rudeness soured CSTAR on this place, more's the pity.  -lethe talk 03:54, 29 November 2005 (UTC)
thread_title: [[User:CSTAR]]

message: Seriously, though, I think Addition needs a content shuffle. Please drop by Talk:Addition#Split.3F. Melchoir 06:00, 28 November 2005 (UTC)
replies: text: Okay, I've got a decent consensus over there, so you may return from the edges of your seats. If anyone wants to help clean up after me, go ahead and visit addition and summation this weekend. Melchoir 19:09, 29 November 2005 (UTC)
thread_title:  [[Addition]] has been overrun by Sigmas! 

message: Wikipedia:Reference desk/Mathematics.  No posts yet. -lethe talk 06:43, 29 November 2005 (UTC)
replies: text: Good move. Dmharvey 12:52, 29 November 2005 (UTC)
thread_title:  math reference desk made 

message: :Copied from Portal:Russia/Russia-related Wikipedia notice board -- Jitse Niesen (talk) 13:44, 30 November 2005 (UTC)
replies: text: I want to thank you for the article you created. We already have Boris Yegorov, Aleksandr Yegorov, and now Dmitry Yegorov. I just thought it helpful to standartize the spelling of this surname. By the way, a disambiguation page would be helpful too. --Ghirlandajo 21:35, 21 November 2005 (UTC)
replies: text: I actually had the same question. The spelling Egorov seems to be much more common. I think I understand where you're coming from: the surname seems to be written Егоров in the Cyrillic alphabet, and the Cyrillic Е at the start is typically transliterated with "Ye". However, I think the fact that Egorov is the common spelling (if that's true) takes priority. What do you think about this? -- Jitse Niesen (talk) 22:35, 22 November 2005 (UTC)
replies: text: The spelling used should be the one under which his English-language papers (or translations to English) are most commonly published. Da? linas 00:38, 1 December 2005 (UTC)
replies: text:  With "Da" meaning yes, in Russian (Egorov would approve :) Oleg Alexandrov (talk) 02:53, 1 December 2005 (UTC)
replies: text: Just a comment, Boris Eltsin is a redirect to Boris Yeltsin. Both Dmitriy and Dmitry are acceptable, I met people who spelled their names both ways, I am not so sure about Dimitri.(Igny 03:37, 1 December 2005 (UTC)
replies: text: According to MathSciNet, 72 papers have "Egorov" in the title (including a Math. Intelligencer article Dimitriĭ Egorov: Mathematics and religion in Moscow, where the last letter of the given name is i-breve), 30 "Egoroff", and none "Yegorov" (Egorov/Yegorov himself died in 1931, so his papers are not in MathSciNet). Given this, I intend to move the page back. -- Jitse Niesen (talk) 13:49, 5 December 2005 (UTC)
replies: text: Obviously the Special:Whatlinkshere/Dmitry_Yegorov will pick this up too, but I thought I'd explicitly point out that that disambig page Yegorov will need to be changed. In fact, generalizing this conversation to the surname in general (and not just that of Dimitri/Dmitri/Dmitry Yegorov/Egorov), perhaps the disambig page could use some working over. --PeruvianLlama(spit) 14:40, 5 December 2005 (UTC)
thread_title:  [[Dimitri Egorov]] or [[Dmitry Yegorov]]? 

message: I was told this project is "the best WikiProject on Wikipedia", so I am hoping someone can help. I would like to equivalently represent the use of the phrase "The page is intentionally left blank" on blank pages. The phrase is a self-refuting meta-reference, in that it falsifies itself by its very existence on the page in question. I made this same request at the reference desk, but only got limited answers. One person suggested using Gödel numbering, while another said:
:"The "self-referential propositional calculus" of Yiannis N. Moschovakis is expressive enough to capture the liar. (Note that Gödel sentences do not capture the liar; they assert their own unprovability, not falsehood.) Moschovakis gives SRP a semantics using least-fixed-point recursion. The liar comes out neither true nor false using that semantics."
But I am at a loss as to how to proceed from here. I will be submitting this article to WP:FAC soon, and would really like to have a paragraph concerning specifically this. Thanks!  — BRIAN0918 • 2005-12-5 02:09
:I'm afraid I don't know enough logic to answer your question. However, I can try to explain the above quote. Firstly, "self-referential propositional calculus" (whatever that may be) is something that probably very few people know about so think carefully whether including it in Intentionally blank page is useful. Secondly, "the liar" refers to the liar paradox, which is not quite the same, as noted on Talk:Intentionally blank page (but if "self-referential propositional calculus" can express the liar paradox, it might also be able to express "this page is blank"; my best guess would be "p = ε" where p refers to the proposition itself and ε is something like the null sequence). Thirdly, in my opinion the link with Gödel's second incompleteness theorem is rather weak and definitely not worth mentioning in the introduction, if at all. -- Jitse Niesen (talk) 13:20, 5 December 2005 (UTC)
thread_title: Requesting mathematical relations for [[Intentionally blank page]]

message: I have proposed the re-creation of :Category:Mathematical model.  Please discuss in Talk:Mathematical model.   Thanks,--Carl Hewitt 19:16, 6 December 2005 (UTC)
thread_title:  Re-creation of [[:Category:Mathematical model]] 

message: Just a note that Arabic numerals has been listed at WP:RFC under mathematics regarding a heated dispute over numerous content changes. Peyna 16:26, 11 December 2005 (UTC)
thread_title:  Arabic numerals RfC 

message: For those who may not know, CSTAR (a well respected math and physics editor) has left Wikipedia, perhaps for good, primarily because of the Carl Hewitt affair. Paul August ☎ 20:39, 12 December 2005 (UTC)
replies: text: Let's hope his comeback tour is planned, though. Charles Matthews 20:42, 12 December 2005 (UTC)
replies: text: Yes let's. Paul August ☎ 21:01, 12 December 2005 (UTC)

text: He told me he would think about returning in the New Year, but he indicated that it was very far from certain he wanted to return.  Carl Hewitt may have been the proximate cause of his departure, but he's had more than his fair share of unrewarding WP experiences.  If he does return, I wish him better luck with what follows. --- Charles Stewart 21:40, 12 December 2005 (UTC)
replies: text:  It seems that R.Koot left for the same reason. I think both of them should have waited for the conclussion of the RfArb against Carl Hewitt, but I do understand how frustrating it should have been to deal with this person. Oleg Alexandrov (talk) 22:08, 12 December 2005 (UTC)
thread_title:  [[User:CSTAR|CSTAR]] has left the building 

message: If you use Yahoo to find references to superlogarithm you will discover some interesting clones of Wikipedia pages. The term superlogarithm appeared on a past version of the tetration page, but now appears almost nowhere else on the net. Now the term superlogarithm appears on both the Free WebCam Tetration and Sex Pictures Logarithm pages of a rather unusual Wikipedia clone at newpenisenlargement.com. Daniel Geisler
:Haven't you heard? newpenisenlargement.com is the number one mathematics resource on the net! - Gauge 02:58, 23 December 2005 (UTC)
thread_title:  Strange Reflections of Wikipedia 

message: I would dearly love to rewrite the following:
:: The finite group can be Z/2Z, Z/2Z+Z/2Z, Z/3Z, Z/3Z+Z/3Z, Z/4Z, Z/4Z+Z/2Z, or Z/6Z, giving 7 families of such surfaces.
I find it almost unreadable, because of the insistence on quotient notation. I would prefer subscripts:
::The finite group can be Z2, Z2+Z2, Z3, Z3+Z3, Z4, Z4+Z2, or Z6, giving 7 families of such surfaces.
From my background, this is merely a matter of different conventions. Yet I get the feeling that some people feel uncomfortable with the subscript notation and habitually use quotient notation. What's up with that? --KSmrqT 11:54, 14 December 2005 (UTC)
replies: text: I think the subscript is preferred for p-adic numbers, and the quotient notation is preferred for modular groups to avoid confusion.  I think it should be OK to use the subscript as long as you clarify that you are talking about the quotient groups. -lethe talk 12:05, 14 December 2005 (UTC)
replies: text: Wikipedia:WikiProject Mathematics/Conventions for where we are on this. Charles Matthews 12:42, 14 December 2005 (UTC)

text: I don't know what article or context we're talking about, but in my experience, the cyclic group Zn is written multiplicatively while the cyclic group Z/nZ is written additively. So, it's a little strange to see "Z2+Z2". On the other hand, it's far easier to read, so I'd prefer it. Melchoir 04:38, 16 December 2005 (UTC)
replies: text:  Curious. Compare your expectations against our conventions. (The original context is not so important, it merely provoked my question; but it was a page mentioned here in another thread, Enriques-Kodaira_classification.) --KSmrqT 08:33, 16 December 2005 (UTC)
replies: text: Huh. Well, I guess conventions wouldn't be any fun if we didn't have lots of them. Melchoir 08:57, 16 December 2005 (UTC)
thread_title:  Integer group names 

message: Today I happened across an old conversaion I had with Oleg a few months ago on Talk:Transcendental number about templates in the math project (the discussion also arrived here; see archive).  We all pretty easily voted to delete them: Template:change, Template:structure, Template:space, and Template:quantity.  I'm a mild inclusionist and was a little nervous about so much deletion, but I was assuaged when I saw Template:Mathematics-footer.  My main concern was lack of consistency across other technical subjects (confer Template:Natural sciences-footer and Template:Physics-footer, for example), and this one addresses that fine.  Today, upon tripping on the old discussion, I noticed that while we do have this template, it's pretty much unused.
So how do we feel about these templates these days?  Are they useful as a navigational tool?  Is it worth having this one for the sake of consistency?  I'm somewhat inclined to add the footer to all the articles mentioned within.  Here it is, for reference. -lethe talk 16:12, 14 December 2005 (UTC)
replies: text: Hey, whom are you calling a deletionist? :) Oleg Alexandrov (talk) 18:23, 14 December 2005 (UTC)
thread_title:  templates revisited 

message: There has been some discussion about renaming the pages linked to from the following template:
The current proposal is as follows:
Current name                        	Proposed name
List of mathematical topics         	List of mathematics articles
List of mathematical topics (A)     	List of mathematics articles (A)
List of mathematical topics (B)     	List of mathematics articles (B)
etc.                                	
List of lists of mathematical topics	List of mathematics lists
Older discussion on this topic may be found at Talk:List of lists of mathematical topics#Renaming this page.
Comments? Objections? If you agree, please state so. -- Fropuff 03:19, 15 December 2005 (UTC)
replies: text: Done. Now is the time to go edit your watchlist and remove from there all the redirects this move created. :) Oleg Alexandrov (talk) 03:36, 23 December 2005 (UTC)
replies: text: Thanks for doing the grunt work on this Oleg. I wasn't looking forward to it. -- Fropuff 04:49, 23 December 2005 (UTC)
thread_title:  Proposed renaming 

message: See Wikipedia talk:Pages needing attention/Mathematics#Listing the pages needing attention for some discussion. Oleg Alexandrov (talk) 05:30, 15 December 2005 (UTC)
thread_title:  Organizing the math pages needing attention 

message: I turn your attention to this article by Nature and Wikipedia's response. Karol 06:04, 15 December 2005 (UTC)
thread_title:  External peer review by ''Nature'' 

message: I have created a discussion page for the implementation of a wiki, Wikipolis, allowing for dynamic collaborations, original research, and some form of peer-review.  I invite you all to add your ideas!--Hypergeometric2F1[a,b,c,x] 10:01, 15 December 2005 (UTC)
thread_title: Original research wiki

message: I wrote the article A linear functional which is not continuous only to immediately discover on its talk page a suggestion to move it to Non-continuous linear functional (darn, everybody should be drunk and sleeping this post-Christmas morning, not checking the recent changes). What do people think (if it matters at all)? Oleg Alexandrov (talk) 17:36, 26 December 2005 (UTC)
replies: text: Isn't there a mechanism for providing both names for the article? Both seem fine... Randall Holmes 17:40, 26 December 2005 (UTC)

text: By the way, I've been steadily editing through this period, and it has been awfully quiet :-)  Happy Hanukkah! Randall Holmes 17:41, 26 December 2005 (UTC)
replies: text:  Yeah, still quiet. :) Yes, there is a mechanism for providing both names, it is called a redirect, see Wikipedia:Redirect. So I guess the argument is about which is the primary meaning, for all that's worth. Oleg Alexandrov (talk) 02:31, 27 December 2005 (UTC)

text: Personally, I don't like the idea of a name for an encyclopedic article beginning with "A". Also, I think the original proposed name is too long. I'd go for Non-continuous linear functional. But maybe it's just me. --Meni Rosenfeld 12:49, 29 December 2005 (UTC)

text: I agree with Meni; initial articles are okay if they are title of a book or work of art, but I don't think they belong in a general article.  Even if it has to do with showing existence.  Isn't there some other way to word it?  Gene Nygaard 21:37, 30 December 2005 (UTC)

text: How about linear map which is not continous, dropping the leading "A" which makes people uneasy. The other option seems to be discontinous linear map, based on above. Oleg Alexandrov (talk) 00:27, 31 December 2005 (UTC)
replies: text:  Discontinuous linear map/Discontinuous linear functional and Infinitely differentiable non-analytic function seem reasonable. We anyway don't expect people to search for and bump into these articles directly, and we are probably going to use these as examples to show that being a "linear map" doesn't imply being continuous, and smoothness doesn't imply analyticity, in main articles on linear maps and analytic functions, so I guess the title is not all that crucial. Bottomline: Unless we are missing on something important, the shorter the better. deeptrivia (talk) 00:44, 31 December 2005 (UTC)

text: However, I find Infinitely differentiable non-analytic function a very clumsy name for An infinitely differentiable function that is not analytic. Oleg Alexandrov (talk) 19:57, 31 December 2005 (UTC)
replies: text: Non-analytic infinitely differentiable function? Septentrionalis 06:29, 10 January 2006 (UTC)
thread_title:  A linear functional which is not continuous 

message: IP, 69.22.98.162 (contributions) has been making edits to Albert Einstein, Henri Poincaré and David Hilbert, essentially questioning the originality of Einstein's theory of special relativity, giving as a source this:  (see Talk:Albert_Einstein#His Theory and Talk:Albert_Einstein#Nobel prise edit), all of which I think have been reverted (by me and others).  I don't really know much about the history of the development of relativity, (beyond what little I've read on Wikipedia), if anyone can shed any useful light on this, your help would be welcome. Paul August ☎ 23:01, 28 December 2005 (UTC)
replies: text: It is true that Poincaré had his own insights into Special Relativity and that Hilbert actually developed a theory of General Relativity about the same time Einstein did, but Einstein’s version was more complete. See History of general relativity and  for some background. I just read an article where it is argued that Einstein’s first wife, who was a physicist, should have been listed as a co-author of his work on Special Relativity or at least been acknowledged for her assistance. Daniel Geisler 05:45, 28 January 2006 (UTC)
thread_title:  Anon's editing of Einstein 

message: * 
Now is your chance to answer the question: Should Wikipedia have redirects for OEIS titles? ☺ Uncle G 01:58, 30 December 2005 (UTC)
thread_title:  Titles from another encyclopaedia