# User talk:Ryan Reich

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Meelar (talk) 23:18, Feb 19, 2005 (UTC)

## 24 hours in a day

Thanks, I never noticed the warning box in infinity symbol.Firedrop (talk) 19:20, 17 May 2008 (UTC)

## Iowa class battleship

Thanx for your edit. I felt like "finest battleship" should be there, but my grammar far from perfect. Now I think you found a perfect wording. TestPilot 19:50, 31 December 2005 (UTC)

## Griffiths

You realise you have to create the Phillip Griffiths page now, I hope. Charles Matthews 20:53, 8 January 2006 (UTC)

## Zariski topology

Thanks for the rewrite at Zariski topology. It's much improved. -- Fropuff 18:00, 24 January 2006 (UTC)

- Wow, you're fast. I just committed that ten minutes ago. I'm glad you like it; it's a shame the thing sat around for so many months without help. Ryan Reich 18:02, 24 January 2006 (UTC)

I have eyes everywhere :) Yeah, I've been meaning to rewrite that article for a long time; I've just never gotten around to it. Too many things to do. -- Fropuff 18:05, 24 January 2006 (UTC)

## By inspection

Hi Ryan. I started a discussion on this article at Wikipedia talk:WikiProject Mathematics#By inspection. I wonder if you could comment. Thanks. Oleg Alexandrov (talk) 02:55, 14 February 2006 (UTC)

## Mathematical jargon

Just wanted to commend you for your recent work on this article. It looks a lot better. dbtfz^{talk} 01:19, 25 February 2006 (UTC)

- Thank you. It was my hope with the new sections that people would see more clearly what jargon had yet to be included, which should help the page grow. Plus it's easier to look things up now. Ryan Reich 04:02, 25 February 2006 (UTC)

- thank you for the symbols on proof by induction. (Where do I go to learn how to do that?) Since I generalised it to begin at an integer 's', we need the range at the end of the line to read 'for all n greater than or equal to s' to be precise. Pliny 19:40, 12 August 2006 (UTC)

- You can write in LaTeX (or a reasonable subset of it, at least) if you enclose it in <math> </math> tags. To learn LaTeX...Google it, there are zillions of tutorials. You'll need to practice to get any good, though. Try typesetting random math documents (don't put that on Wikipedia, of course). Also, it would have been more appropriate to start a new section on my talk page rather than burying your comment in a very old section. Ryan Reich 19:57, 12 August 2006 (UTC)

## wikiproject mathematics

Dude surely you must add your name to Wikipedia:WikiProject Mathematics/Participants.

Dmharvey 22:59, 25 February 2006 (UTC)

- David, I was just about to leave a message on your page. It's scary now that real people I know can read me on Wikipedia too. Ryan Reich 23:00, 25 February 2006 (UTC)

## limitation of size

Hi Ryan,

a redirect to NBG is not what I was looking for. I want a discussion of the *philosophical* concept, not a formal theory that arguably incorporates it. --Trovatore 23:09, 25 February 2006 (UTC)

- My apologies. I jumped on it too hastily when I found a requested article whose title actually rang a bell. These days, most of them don't, and I assumed that's what was meant. I couldn't tell who had placed the request, so I figured, given the similarity, that it might well be someone who came across the term in a book, couldn't trace it to the NBG page, and asked for an article. Ryan Reich 07:09, 26 February 2006 (UTC)

## Three forms of mathematical induction

Thank you for your contribution to the discussion page regarding AfD for this article. I found it very constructive and helpful. Slowmover 16:16, 7 March 2006 (UTC)

- Glad I could help. I hope that I can influence enough people (one way or the other) that the debate has a resolution rather than being inconclusive, which is disappointing. Ryan Reich 17:19, 7 March 2006 (UTC)

- The AfD debate was inconclusive, but I am still trying to get Michael Hardy to accept something like my reformulation of his insights, placed as a
*section*of Mathematical induction. Since my reformulation inadvertantly mimicked an insight about binary functions that you posted first, I would like to invite you to participate in the discussion at Talk:Mathematical induction. (I've been talking to Hardy at User talk:Michael Hardy, so please check there, too.) Joshuardavis 19:27, 12 March 2006 (UTC)

- The AfD debate was inconclusive, but I am still trying to get Michael Hardy to accept something like my reformulation of his insights, placed as a

## not sure you realize how that sounds

Hi Ryan,

Are you aware that "I can tell you where you should try to merge it" can be read as a vulgar insult? If not, you might want to rephrase that. (If so, you might still want to rephrase that.) --Allen 01:29, 8 March 2006 (UTC)

- Obviously I didn't realize that. If it comes off badly I'll change it. Ryan Reich 01:33, 8 March 2006 (UTC)

- Thanks... I apologize for suggesting that you might have meant that. I may be the only one who read it that way, but in case I wasn't I felt I should say something. Sorry again. --Allen 01:37, 8 March 2006 (UTC)

- No problem. I write so many words eventually they'll say something stupid. Ryan Reich 01:38, 8 March 2006 (UTC)

I can easily believe nothing was being insinuated, but given the accusations and harsh tones already in the discussion, I believe it's wise if you modify that statement and note in the edit summary that it was not meant to be an insult. Better safe than sorry. --C S (Talk) 01:41, 8 March 2006 (UTC)

- Yep, it's changed now. I'm trying hard to keep my criticism of the article from reflecting on the author. Ryan Reich 01:48, 8 March 2006 (UTC)

Yeah, I was positive that you didn't mean anything nasty when I read it, and I'm sure Michael wouldn't have taken it the wrong way... but I still had a laugh. It could have been an instant Wikipedia classic! I guess it just goes to show the dangers of communicating through text. Anyway, let me add my thanks to you for spending so much thought on the AfD. Cheers, Melchoir 01:56, 8 March 2006 (UTC)

## Thanks

Many thanks for your stellar work on Common misconceptions in probability and statistics (or whatever its current title is). I had given up on that article, but you are probably right that User:Helgus meant to explain the difference between statistical independence and causal independence. This is an important point, and it wasn't yet mentioned on Wikipedia, so I'm very glad if it will be saved because of your efforts. -- Jitse Niesen (talk) 02:31, 29 May 2006 (UTC)

- I'm glad it will turn out to be useful. At first I thought the article would end up proving to be OR anyway, but the example seems not to be, and the philosophical point is certainly worth a page. Though his original article talked about "information", which has me wondering if there is, in the mathematical sense, information between dependent events. Not that I know anything at all about information or probability. Anyway, even if the article gets deleted I'd be happy to find the causal/statistical independence dichotomy a more suitable home. Ryan Reich 02:45, 29 May 2006 (UTC)

## Did I offend you?

I see no relation between your "we disagree" statement and what I wrote, and don't understand why you write that you're "through". If I offended you in some way, I'm sorry. --Lambiam^{Talk} 16:28, 30 May 2006 (UTC)

- Maybe unintentionally. More to the point is that in general, what I enjoy about Wikipedia is much more creating articles than deleting them; arguing over what should or should not be said is not rewarding for me. The participants in these arguments (including myself) are always hugely dismissive of the topics they oppose, as is true of any asynchronous Internet communications, but they are only ever justified in this in the case of the most frivolous or deliberately fraudulent articles. I often find myself defending material which is being attacked as "unencyclopedic", but which I think is important to any writing on mathematics. I take this as a sign that I don't get along with the enyclopedia model, and I don't want to have anything to do with the legal wrangling. I'm through with AfD's. Ryan Reich 21:00, 30 May 2006 (UTC)

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## Helgus’s request

Dear Ryan,

Many thanks for the help in editing wiki-papers. Obviously, my English is not perfect. Moreover, your help was rather pertinent and indispensable. I understand, that you are very busy. And nevertheless I'd like to address to you with the request of the same sort.

On July, 30th I leave for Paris on Conference IPMU-2006, where I have the session E22 on eventology.

Would you be so kind to find a spare minute and examine preambles of two wiki-papers from the point of view of your excellent English style?:

Thank you in advance:) - Helgus 04:25, 24 June 2006 (UTC)

## Rational map

Hi Ryan, why do you hesitate to post your draft on rational maps? I think it is valuable. Some of the material, e.g. dominant map, might also be good to add to the Glossary of scheme theory. Jakob.scholbach 04:36, 13 March 2007 (UTC)

- Laziness? I guess I should get it out there, it's been ages. I just never feel like it's truly correct (from a mathematical-philosophical standpoint). Ryan Reich 04:56, 13 March 2007 (UTC)

Just post it and others, maybe myself may see whether they want to add, rearrange etc. something. Jakob.scholbach 15:36, 13 March 2007 (UTC)

- Well, I put it up and structured it a bit. Ryan Reich 16:14, 13 March 2007 (UTC)

## Mathematics CotW

Hey Ryan, I am writing you to let you know that the Mathematics Collaboration of the week(soon to "of the month") is getting an overhaul of sorts and I would encourage you to participate in whatever way you can, i.e. nominate an article, contribute to an article, or sign up to be part of the project. Any help would be greatly appreciated, thanks--Cronholm144 00:05, 14 May 2007 (UTC)

## Abel Rating

Hey Ryan, I notice your change to the article and I am fine with it, but I encourage you to address the comments in the comment box. thanks--Cronholm144 00:30, 16 May 2007 (UTC)

- I'm thinking about it. Depending on how familiar you are with my edits, you might have noticed that I tend to write as much as I can when I create an article. So, if I don't write something, I don't know it. I changed the rating just because I realized that it wasn't actually a stub. Ryan Reich 00:58, 16 May 2007 (UTC)

Well I knew that it was not a true stub but it needed work and I sometimes rate lower than the article's true value, which I think is start, in hopes of attracting angry editors who will improve their article to prove me wrong;), but if that is all there is to say then that is all there is to say on the topic. However I wonder if there is another editor who could help expand the article? anyway thanks so much for your prompt reply--Cronholm144 01:14, 16 May 2007 (UTC)

P.S. Help out with the Math collaboration of the week Mathematical physics if you have time!

- I don't mean to imply that there's nothing more to say on the Abel-Jacobi map; just that I don't have anything more to say. I know nothing about abelian varieties and I only know this bit because of a reading course I did last year. Hopefully I'm not the only "algebraic geometer" around here. Ryan Reich 02:20, 16 May 2007 (UTC)

## Image:tinfoillinux.jpg copy to Commons?

Just curous, what is the meaning of the {{to Commons}} template you've put on this image today? It seems to imply that you think the image is inappropriate for some reason, i.e. being indiscriminately included. Do you think that Tinfoil Hat Linux does not deserve an image of its logo on its page? Or is it simply that you think that the image itself belongs to be hosted on the Commons site rather than on Wikipedia itself? I am not experienced in these political matters, so I don't know what the rule is with where images of various licensing belong. Ryan Reich 16:50, 23 October 2007 (UTC)

- As it is the image can only be used on the English Wikipepia, but since it's a free image it can be copied to commons. Then it will become available on all Wikimedia projects. It's certainly not tagged because it's inappropriate, but rather the opposite. // Liftarn

- Okay, cool. I'm just being vigilant about my pet articles; from time to time, people do things which are perhaps well-meaning, but still quite wrong, on the "advice" of some guideline or other. Ryan Reich 17:39, 23 October 2007 (UTC)

## Mathematical jargon

Hi, I noticed your undo of my edit to Mathematical jargon. The reason I made my edit is that your definition of "stronger" doesn't cover the one I gave (although it gives related meanings), and the one I give is the only one I encounter on a regular basis. Undoing doesn't fix that. Please suggest a solution. Rp (talk) 07:32, 28 January 2008 (UTC)

- It looks to me like what you said:

"A property or condition is said to be

strongerthan another if the second property holds in all cases where the first property holds, but not vice versa; e.g. for positive whole numbers, being divisible by 4 is a stronger property than being even, while being divisible by 3 is neither stronger or weaker than either.:

- is exactly the same as what is said in the final sentences of the existing definition:

"Finally, the adjective

strongor the adverbstronglymay be added to a mathematical notion to indicate a related stronger notion; for example, a strong antichain is an antichain satisfying certain additional conditions, and likewise a strongly regular graph is a regular graph meeting stronger conditions. When used in this way, the stronger notion (such as "strong antichain") is a technical term with a precisely defined meaning; the nature of the extra conditions cannot be derived from the definition of the weaker notion (such as "antichain")."

- Did you have something else in mind? Ryan Reich (talk) 21:44, 28 January 2008 (UTC)
- Hmmm, looks like you're right. Then all I am unhappy with is the word "notion", where the term "property" seems common to me; and the lack of a formal definition (subset would do in most cases). Rp (talk) 20:15, 30 January 2008 (UTC)
- Seeing them together like this I'm not sure I don't prefer your version, though. When I originally wrote all the definitions on that page, I wanted to keep them very short, since it's a big list and many of them have articles elsewhere. "Strong" is easily the worst offender in terms of length and I don't think it is necessarily better than an efficiently worded, shorter version. However, the point made in the last sentence of the current definition is a good one: sometimes, "stronger" is not a value judgement but just jargon for "subset of". Ryan Reich (talk) 03:13, 31 January 2008 (UTC)

- Hmmm, looks like you're right. Then all I am unhappy with is the word "notion", where the term "property" seems common to me; and the lack of a formal definition (subset would do in most cases). Rp (talk) 20:15, 30 January 2008 (UTC)

## Inherent notability

Hi Ryan. Given your recent comments, I just thought you mind find this entertaining (if somewhat worrying). I'll never forget that particular AfD, in which people it was argued that a misprint (in all probability) was inherently notable. To my mind, that's why the concept is so absurd. Jakew (talk) 22:00, 2 June 2008 (UTC)

- This really is absurd. At least the article was moved. Ryan Reich (talk) 22:13, 2 June 2008 (UTC)

## Inherent notability and FritzpollBot

Hi Ryan - as you may know, the community reached consensus in relation to FritzpollBot. I believe that there is no such thing as inherent notability, per your arguments during the discussion. What I was interested in hearing was your thoughts on creating full stubs (oxymoron? :) ) on places with sources to verify notability per the only presently available guideline but creating lists of the places in particular administrative districts with information such as coordinates, population data, etc. One option might then be a redirect from the placename to the list, but I'm not sure. Anyway, this and many other discussions will be taking place at a centralised location, which we should be able to find in the next 48 hours, but if you would like to contribute, can you drop a line over at User:John_Carter/GEOBOT_group. I think we could certainly use your guidance, as I'm pretty certain WP:NPT won't become a guideline any time soon Fritzpoll (talk) 12:29, 11 June 2008 (UTC)

- Thanks for telling me! I'd be happy to participate in a day or two, when I return from my present mini-vacation. Ryan Reich (talk) 21:32, 13 June 2008 (UTC)

### Creating geo lists

Hi I've made an intital suggestion at the GEOBOT talk page in that it would be an excellent idea to generate a full lists of places in a tabled list. Once this is accomplished we can work through what articles could be started in their own right if there is enough info avilabale. I see it as a solid comprehensive base to build geo content on if we have a full world list organized like this. See Wikipedia talk:WikiProject Geography/Bot#Creating lists. Please offer your thoughts thanks **♦Blofeld of SPECTRE♦**^{ $1,000,000? } 14:25, 21 June 2008 (UTC)

## Cayley–Hamilton

Ryan, I've seen your edits on the Cayley–Hamilton article, and I appreciate that you informed me on my talk page, since indeed I had invested quite a bit of time in the part that you replaced. The text you replaced it with is interesting, but in my opinion not an improvement, even though it seems essentially correct (I have a few gripes but these are not so serious). But I'm probably not the most neutral person to judge, so we'll see how your change fares by other editors opinions. Let me just say a few things that come to mind.

- Your text frequently (at least four times) mentions the "defining property" of adjugates. It is important, but not "defining". The definition of the adjugate is that its entries are certain minors, and the mentioned property follows from that. If the property were "defining" any zero matrix could have any matrix of the same size as adjugate.
- You say "a lot of the pedagogy of comparing and correcting incorrect proofs has gone by the wayside as a result of the last one". I don't understand the phrase, which one is the last one?
- Your first edit summary mentions a didactic diatribe, but I did not want to push any didactic point. It is just that I think it is really a singular property of the Cayley–Hamilton theorem to inspire false proofs, and it is valid for the article to say so. I've seen many false proofs, some in print; before I edited the article
**all**the proofs given there were false (rest assured, yours are not). Most false proofs are more sophisticated than bluntly substituting*A*for*t*in the defining equation of the characteristic polynomial, but they are false anyway. The thing that worries me most about the text you substituted is not that it it will mislead people, but that it will soon get replaced by people honestly convinced that they can do better than this. - While interesting, none of the proofs given gives me the impression that it touches the essence of why Cayley–Hamilton holds (well the final argument invoking Euclidean division comes close, but phrases like the one starting "This incorporates the evaluation map" put me off (frankly I don't understand what it is affirming) and seem to have little to do with Euclidean division). The first three proofs are all quite long, and apart from the first one I doubt there are many wikipedia users that can actually understand them (given that their average level seems to be high school). The second took me long to absorb, and the essential point, that the determinant of
*B*is*p*(*A*) needs more thought than is suggested. - You say some of what I wrote is simply not true. I would appreciate if you were more specific. And then, you could have corrected (and added the proofs you did) without throwing away everything.
- The proof I wrote was loosely based on a book I found in our library (being dazzled by all the wrong proofs I looked for some solid ground), which happened to be an algebra course by Patrice Tauvel (in French); I undid it of some of what seemed to me unnecessary generality for the context at hand (it arrives at the Cayley–Hamilton theorem as a corollary to something more general). The consideration of Euclidean division was a result of discussions with colleagues at our math institute. But later I found much of it also on the French wikipedia (in some indirectly related article I cannot trace right now), so there is no point in claiming (or being accused of) original research here. In fact somebody sent me a paper reviewing some 20 different proofs... It seems like that many people have been thinking about this.
- I regret the disappearence of some points
- the observation that the inital naive method not only gives a wrong argument, but also leads to the wrong conclusion (a scalar rather that matrix 0).
- the observation that confusion arises from confusing unwritten (matrix and scalar) multiplication operations
- the example that shows how naive substitution leads to genuinely false identities
- the (before last) expression that shows that the adjugate of
*A*is in fact a polynomial in*A*(with coefficients taken from the characteristic polynomial of*A*). This is an inportant and very general fact, which implies Cayley–Hamilton immediately, without being as easily implied by it.

Marc van Leeuwen (talk) 20:21, 4 July 2008 (UTC)

- Thanks for replying! My response:

- The reason I keep saying "defining property" is that it's hard to number equations in Wikipedia, and I need some other memorable device to refer back to them. Perhaps I will do as you did and insert (*) next to this one.

- "The last one" referred to the last item in the previous sentence (which you didn't copy here), namely, that your text was sometimes opinionated. Basically, it seemed to me that your main goal was to correctly instruct the reader in the art of proving Cayley-Hamilton, and in particular, to push the point that trying to use the evaluation map directly could never work. All of your examples, including one example false proof, made this point; this is the thing that I thought was not right in what you wrote, since in fact it
*is*possible to formulate a proof correctly using the evaluation map (you just have to be more careful, as in the third proof I wrote). The whole effort seemed "didactic" in that it was primarily concerned with correcting a misconception and instructing the reader through numerous but subtly different arguments that the only path to a proof of the Cayley-Hamilton theorem is through "real work" (that phrase really did have to go, by the way).

- Concerning the loss of these subtly different arguments: looking back at the last version of the page before I edited it, the two big points you made were: there is no evaluation homomorphism from
*M*[*t*] to*M*(in my notation), because*A*is not in the center of*M*; and, direct evaluation of the equation - at
*A*leads to equating a matrix,*p*(*A*), with a scalar, det(0); a sub-point of this is that even replacing*t*by*A*on the right requires one to reconcile three things:- That
*t**I*_{n}is a diagonal matrix with*t*on the diagonal, so substituting*A*gives a matrix with matrix entries; - That
*A*itself, as it appears in that expression, is a matrix with scalar entries; - That if we interpret
*t**I*_{n}as the "quantity"*t*multiplied by the matrix*I*_{n}, substitution of*A*for*t*transforms a*scalar*multiplication into a*matrix*multiplication.

- That
- You also think that these are among your main points. The one about there being no evaluation homomorphism is the one I think is wrong (given the proper context, and this distinction
*did*make it into my version). As for the others, I actually think that they have been partially retained in my text, although perhaps in an excessively terse form. The first numbered point and its comparison with the second are explicitly in my text right before the first proof. I did miss the opportunity to give the "matrix equals scalar" dichotomy, but there is an obvious place to do so also right before the first proof, and I will make that correction. The point about multiplication is also implicit in the juxtaposition of the second and third proofs, though as you observe, the proofs as a whole are long and detailed, and perhaps extracting their "meaning" is not easy. I will expand the discussion before the proofs in order to reincorporate these points.

- The reasons I replaced your analysis of erroneous arguments with just some proofs are that first, I felt that the existence of my third proof invalidated your frequently-expressed assertion that there could be no proof based on the evaluation homomorphism; second, although the above points are worthy ones, they could be easily expressed more briefly in the context of
*correct*proofs, rather than as criticisms of incorrect ones; and third, that what was there concerned itself at least as much with educating the reader as with informing them. The second and third reasons are both related to the nature of the medium here: since an article is not a discussion, the false arguments you shoot down are more of the nature of a straw man than a real opposing position; and since it is also not a page in a textbook, the instruction you provide doesn't reside in the proper context for it to be received as intended.

- I didn't mention original research because I think that any attempt to be philosophical about the proof of any theorem borders on it (comparison of proofs is not a major mathematical activity, although you say that for this theorem, it may be). I believe that a discussion such as you wrote is a good idea, but that to have the discussion in full requires a more scholarly medium.

- This also goes for the proofs I included. I liked the third one much more before I started to write it up, at which time I realized that the story for
*Z*is not as nice as I had thought, since it is not commutative. The whole thing ends up being a little technical, whereas the concept, which is to restrict the evaluation homomorphism to a context in which it*is*a homomorphism but still does the job intended for it, is quite simple. The fourth proof based on your Euclidean division idea is much more elegant. You say that you don't feel like any of the proofs gets at the "why" of the theorem, except maybe the fourth, but I think that the second one is really the best (this is somehow to be expected, given the author). My reason is that since (as we both agree is essential)*p*(*A*) is to be the zero*matrix*, and since matrices are naturally endomorphisms of vector spaces, this should be verified by considering its action on a vector space, and not simply by having*p*(*A*) = 0 pop out of a piece of algebraic machinery. Using the evaluation homomorphism is an elegant trick, but polynomial algebras are at their core a piece of algebraic machinery, a formal device; in the second proof, the matrix*B*is literally the matrix-with-matrix-entries which is*t**I*_{n}-*A*, evaluated at*A*, and with the*A*already appearing considered as having matrix entries (which are all scalar matrices). This interpretation is consistent with the idea of using "actions on vector spaces" in the proof. That det(*B*) =*p*(*A*) is clear once this point is made; perhaps it needs to be made better, but I think this proof (which, unlike the last two, is sourced) is an important part of the philosophy of this theorem.

- As for the fact that Adj(
*A*) is a polynomial in*A*, of course, I did make that point in the fourth proof. I didn't mention that the coefficients are those of the characteristic polynomial, though that would of course give still a third way of using the Euclidean division technique to prove the theorem (the first two are: do division, observe that the remainder is*p*(*A*), and also that the remainder must be zero; do division, observe that the quotient is in*k*[*A*][*t*], and then show that the evaluation map is a homomorphism).

- The main thing I'm getting out of this discussion is that the theorem is even more interesting than I had thought. What is this paper with the 20 proofs in it? I'd like to see it. Ryan Reich (talk) 17:13, 6 July 2008 (UTC)

## Change of Variables (PDE)

Hi Ryan,

The theory is in section 2. If you don't think the theory is well-presented, please improve the exposition.

Change of variable for PDE is not much discussed but it is an essential technique. Change of variable for integral equations is discussed in Integration by substitution but this doesn't really give you much help.

Also let's continue this discussion in the article's Talk page.

Thanks, Erxnmedia (talk) 13:42, 18 July 2008 (UTC)

## manifold destiny

Hi, The "reactions" subsection has undergone a bit of an edit war. I already left a comment at talk:manifold destiny, perhaps you could offer an opinion. Katzmik (talk) 14:19, 22 September 2008 (UTC)

## Algebra stub template

Dear Ryan,

Before I respond to your comment, I would just like to note that I accepted Ozob's idea at some point in the discussion but that at that point, people conveniently changed their minds to choosing the Rubik's cube. I don't mind you changing the image as such (I could have reverted and continued pointless dispute but I didn't. So really you didn't end the discussion; I agreed with your idea), but I feel that I might look into this later on. The discussion:

1. Started out with me wanting to know how to find a good image (in fact I was happy with a*b = c) but then I saw the commutative diagram.

2. I started supporting the commutative diagram hoping for some back-up but it didn't come. By then, I had argued for so long, I did not want to give up (not because I wanted to waste more time but because I felt strongly about the image).

As you mentioned, this discussion was a waste of time and one of the reasons why I was unwilling to accept the Rubik's cube idea, was because I had been 'for my idea' for quite a while (ask yourself what you would have done in the same position if you felt strongly about a particular image and had argued for 1 page about it). Anyway, my response to one of your comments:

*the icon should be "real math" and by that you meant category theory, that only "real mathematicians" need understand it, that the template actually function as an instructive device*

- I never mentioned (or even implied) that real math was category theory; I only said that math symbols such as sqrt (x) or the Rubik's cube was not real math (in my opinion, but I think that you will at least agree that sqrt (x) is not real math).

*One of*the purposes of the template was to function as an instructive device; the other purpose is of course to represent algebra.

By the way, I don't want to make a pointless discussion out of this but I suspect sockpuppetry at some point in the discussion (see the contributions of User:Brwian). Perhaps one user created an additional account for more support. I am also sure that if more users participated, I would have got some more support (especially by algebraists who specialize in homological algebra).

Topology Expert (talk) 08:48, 20 November 2008 (UTC)

## I've been avoiding this for too long....

Wikipedia:Village_pump_(policy)#Needs_resolution:_Are_places_inherently_notable.3F - I've initiated a question that I feel needs asking and which you may be interested in Fritzpoll (talk) 08:31, 15 December 2008 (UTC)

## Agent provocateur?

See my comment on the Grothendieck talk page. Feketekave (talk) 04:38, 30 December 2008 (UTC)

## TUSC token 586f1edd864d37b8a89eae0a31d5f150

I am now proud owner of a TUSC account!

## Flagged revisions alternative

I came across an alternative to flagged revisions on Jimbo's talk page today. If you didn't know, there was an error on the page about Ted Kennedy that stated that he had died. Though the edit was corrected within five minutes, the change prompted some to ask for *flagged revisions*, meaning that all edits had to be checked by established users. Anyway, I think the alternative suggestion is good—do you know how I can propose and maybe get a vote on it? Jchthys (talk) 04:12, 4 February 2009 (UTC)

## QED dab (quantum electrodynamcs)

I see you took this out. I must admit I was tempted to do the same. I couldn't make up my mind. In all these cases, which are kinda a tough call, I dunno really what the rule of thumb is. Any advice?

Like I just tried to think "where would someone looking for quantum electrodynamics" end up and also "is it doing any harm?". The last is weaker because otherwise, yeah, might as well just stuff everything in as a seealso or whatever, from querelous erratic damned children to quite educated democrats (that's a very short topic).

It's a hard one to call. SimonTrew (talk) 16:50, 21 May 2009 (UTC)

- Not that you should have known this, but a while ago this exact sequence of edits was performed by two different users on Q.E.D., and the guy playing my role gave the same justification for reverting, so you might say I had prejudice. Still, I have reasons. I agree that the note does no harm, but it does single out just one of the alternatives when in fact I would say that in addition to the mathematical phrase, the ones most likely to be searched for are the physics theory, the Feynman book, and the play. When it's a choice between one of the two Gromov's compactness theorems, say, there is a good reason to point to one in particular, especially since they have the same name. I note that people searching for any of the other QED's would not put in periods at all, so wouldn't end up at Q.E.D but at the dab page. In this case the dab page is pretty nontrivial, so rather than psychoanalyzing the users of each particular article I think it's best just to point them to the nexus. Ryan Reich (talk) 17:36, 21 May 2009 (UTC)