User talk:Charles Matthews/Archive 1

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Kasing, China

Great article on Shiing-Shen Chern!

What's your source for his birthplace being "Kasing"? I googled and could find none [1]. Was it a book? Don't worry, it is not wrong; the place is spelled (although the Chinese characters have always been the same) as Jiaxing now (pronounced like Jeea-sing). Because I find this romanization (if real) very interesting; it's probably a dialectal pronunciation. I want to include it in Jiaxing that I'm writing, but I don't want to if it's a typo or just too little an idiocyncrasy. --Menchi (Talk)â 12:42, 8 Dec 2003 (UTC)

I was working from his Selected Papers. I checked and it's Kashing, Chekiang province.

Charles Matthews 12:45, 8 Dec 2003 (UTC)

Yep, "Kashing" gives lots of google hits. Terrific! --Menchi (Talk)â 12:49, 8 Dec 2003 (UTC)

Transp. Dysp.

I apologize for the pathetic wording re Transposition cipher :) Dysprosia 10:17, 10 Dec 2003 (UTC)

Problem no.

Charles Matthews 10:25, 10 Dec 2003 (UTC)



Revolver drops by

Charles,

Thanks for all your work. I have trouble keeping up with you! (I also have more immediate demands..., like graduating). I'm learning a lot from your articles. (I'm really only familiar with the little patch of number theory I work in.) Your contributions make the math area one of the best in the wiki (as if I really read anything else...) Revolver 17:40, 9 Feb 2004 (UTC)

Actually I have something else I should be working on right now - but that's fighting back. Assume guilt on my behalf. Nice to hear from you, anyway.

Charles Matthews 17:42, 9 Feb 2004 (UTC)


RFA

Hi Charles, good work on the mathematics topics. I have nominated you for adminship, please reply at Wikipedia:Requests for adminship#Charles Matthews if you accept the nomination. Dori | Talk 17:58, Feb 9, 2004 (UTC)


Formatting mathematics

Thanks to all who have worked on the format here. Caveat: what is good for one browser may not be good for all.

This is something I always worry about. There's always a conflict between nice formatting and maximum availability. Although, I find it hard to imagine how someone can really explore the math articles here beyond the basics without being able to view the tex in math mode. There are just too many things that are impossible to render in HTML, even if you try. These are some of the guidelines I use, I'm open to comments.
  • I think math mode should ALMOST NEVER be used with inline text. Put another way, I think math mode should almost only be used set off separately. I don't think everyone realises the reason for this -- it's not just that it looks awkward; people can set their HTML text to different sizes, while the math mode stays the same size. This really makes it look awkward across different text sizes. It seems to me, if you want to write something inline, but you can't seem to render it using the additions available to HTML, then it's probably exotic or strange enough that it should be put in separated math mode.
  • Sometimes I'll take things that could be done in just HTML and make them in math mode. I try to have a good reason for this, usually this is readability; i.e. in HTML it's very difficult to read. An example would be the e^(blah) expression; in HTML, unless you use super-large text, the exponent is hard to read, so I think exp(blah) in math mode works better.
I realise these are sometimes subjective decisions, so if someone disagrees with something, you can change it (an explanation is nice, but not necessary). The only thing I stand pretty firmly on is the first thing above, I just think math mode should be used inline only as an absolute last resort. (I believe this is wikipedia policy.)

Revolver 18:00, 9 Feb 2004 (UTC)

Time

Hey Charles,

Thanks for splitting the intellectual history of time section into time in physics and what is left now. I think this arrangement works better.

Kevin Baas 21:23, 15 Feb 2004 (UTC)

Monad, Axel steps in

Charles, I edited monad (category theory) and I believe that the article was mixing monads and comonads, so please check. Also, I could not come up with a good description of the map T(T(X)) -> T(X) in the example. What is it anyway? AxelBoldt 15:15, 23 Feb 2004 (UTC)

On the example: if Free(X) is the free group on the set X, then there is a fairly obvious concatenation map C:Free(Free(X)) -> Free(X), where the LHS is 'abuse of notation' for the free group on the set underlying the free group on X. In words, what C does is to take strings of (strings of elements of X and inverses) just to strings, by dropping all parentheses. This, I think, is a fundamental example, and even more basic for free monoids (where it is a little clearer, also). As for mixing monads and comonads, it is very easily done since these are dual concepts - I don't immediately see a definite mistake.

I think the motivation in relation to adjoint functors needs to be emphasised - otherwise it is hard (from my perspective) to see why this is an interesting concept. I realised quite recently that there are some quite basic intuitions (monads are about 'closure', comonads are about 'propagation') that help to distinguish the ideas; but one step at a time! Obviously one can proceed by generalising the closure operator side first.

Charles Matthews 15:36, 23 Feb 2004 (UTC)

User:COMPATT

Recently I have tried to make two edits to the article on periodic functions since it is a redirect for periodic and the current article seems heavy on the math. I use the term "heavy" simply because some of the people following links redirected to this article could be those whose math skills may be rusty to non-existant. I believe I understand the reason for the reversion you made on my first edit. I do think a rewording to make it more "accurate" in the context of the article would have been better. I am still not sure why my second attempt at bringing in some common examples was reverted as well.

My intent is not to change the content of the article, but to assist anyone who may arrive at this article via the periodic article which redirects to periodic function. It would be a waste to try and write an entire article on the word periodic since the layman's understanding of the term is so close to the subject of this article. I just think some readers may be put off by all the math and a simple one or two sentences added to this article at the beginning would satisfy the needs of a novice reader while giving them the chance to expand their knowledge by continuing to read the rest of the article. I realize a dictionary would provide the same assistance, but I do not see the harm in generalizing a little more at the beginning of the article for the benefit of those who are simply "passing through". It may even be beneficical to the article because it would let such passersby in on the greater depth of meaning associated with this subject. I have used this approach on many articles and this is the first one I have had resistance on. Perhaps my attemps are not appropriate for this type of article, but I do see a need which someone needs to satisfy.

COMPATT 17:42, 24 Feb 2004 (UTC)

I didn't revert (which would mean sending the page back to the state before you edited it). I rewrote and expanded what you added. Please understand that this is not 'resistance', as you put it, but the normal process, as explained by text under the edit box.

Charles Matthews 17:48, 24 Feb 2004 (UTC)

My apologies! I am still not used to reading these edit histories and obviously jumped the gun! Your version (now that I have seen it) is much better than what I was trying to do. (...) Thanks for your quick response to my inquirey. Feel free to revert this portion to give yourself more room for more important things or leave it as an example of "open mouth insert foot".

Symplectic space

Charles, I don't know if you saw my comments on Talk:Symplectic space before you redirected the page (which I did than undid a couple days ago). Should we have a separate page on linear symplectic spaces?

Fropuff 15:30, 2004 Feb 25 (UTC)

Under the 'old' name, alternating form or skew-symmetric form, there is some basic algebra and I'm not sure we have that yet. Yes, somewhere - it isn't obvious to me that linear symplectic space is good except as a redirect name. I always think of these as alternating forms. By the way, none of the theory seems to be that well founded until one has Darboux's theorem.

Charles Matthews 15:36, 25 Feb 2004 (UTC)

Yeah, I agree. I guess the few pages now referring to symplectic space are using it to mean a manifold anyway, so it works for now.

Fropuff 15:47, 2004 Feb 25 (UTC)

numbers...

By all means, please remove the protection and help shape the article. That would be terrific. Kingturtle 17:27, 7 Mar 2004 (UTC)

Noether's Theorem

Okay. Is there a simple way to derename a page? --wwoods 18:47, 1 May 2004 (UTC)

I don't know one - but then I'm hardly an expert on the technical side.

Charles Matthews 18:52, 1 May 2004 (UTC)

If no one has edited the redirect created by the move, the page can just be moved back as if there was no page already there, which is what I've done as the original move broke a number of redirects and didn't seem to follow naming conventions. Angela. 11:40, May 2, 2004 (UTC)

Thanks. Charles Matthews 11:59, 2 May 2004 (UTC)

Fatou, Julia and Mandelbrot sets

Charles, thanks for tidying up the page I created on Pierre Fatou and looking up his born/died dates. In a later edit you added a comment about Mandelbrot sets being the popular name for Julia Sets. They are actually quite different; I updated the article with a more detailed description of the relationship between the work Fatou did, Julia's work and how this relates to the later work by Mandelbrot. The Mandelbrot set actually classifies the Julia sets - points in the Mandelbrot set have a connected Julia set and points not in the Mandelbrot set don't. The extra research was quite interesting as Julia and Fatou were coming up with their ideas at the same time and their theories were so similar, they are now referred to as the 'Fatou-Julia Theorem'.

Mark 20:33, 2 May 2004 (UTC)

With your interest in Hadrian's Wall, you might be amused to know that I was brought up within sight of Lanercost Priory. And relatives used to farm at Greenhead. Charles Matthews 14:55, 3 May 2004 (UTC)

Coase Theorem

Go ahead and change it back to lowercase if you want, but it's definitely uppercase in an economics textbook I have. I personally seem to see more capitalized than uncapitalized theorems, and I think the convention at Wikipedia talk:Naming conventions (theorems) is flawed (I definitely see "Pythagorean Theorem" more often than I see "Pythagorean theorem"), but I'm not going to go against everyone else on this. In any case, thanks for letting me know about this (it's much nicer to see people like you than people who just overwrite other people's changes without any attempt at all at discussion). --Lowellian 01:12, May 5, 2004 (UTC)

You look like me

So, I reviewed all the faces in the facebook, and I declare that you look the most like me. So, I hope that when I visit London this summer, you will have time to visit with everyone, so we can prove it in person. Jimbo Wales 00:32, 6 May 2004 (UTC)

Actually, that would be cool. Perhaps I have a career as your body-double. I could do the autographs for you, too. :)

Charles Matthews 05:38, 6 May 2004 (UTC)


What did you think about my edits to the curves page. Should I start a new differential geometric curve page ? MathMartin 09:19, 7 May 2004 (UTC)

No, the curve page has to mention all major aspects (this is policy). If you and Tosha are mainly disagreeing about the order of topics on the page, that can be discussed on the talk page. You made a major edit to a page that had already had a great deal of work done it - without discussion. Obviously, the old page wasn't perfect. Now you have to discuss with Tosha, who is an expert, to clarify the issues about the page content. If in the end there need to be some new pages, OK, why not?

Charles Matthews 09:24, 7 May 2004 (UTC)

I think your edits on the curve page are very good, especially the formatting. MathMartin 17:42, 7 May 2004 (UTC)

Thanks. It's going to take a bit more work, but don't ever think your editsd have been lost sight of.

Charles Matthews 17:50, 7 May 2004 (UTC)

I do not remember my history section being so good :) MathMartin 17:54, 7 May 2004 (UTC)

Direct sum and &isin

Could use your advice on Talk:Direct sum. In addition, is the character for "is an element of" broken? I recall it being &isin but it is showing up on my computer as an arrow. Thanks! Goodralph 23:22, 11 May 2004 (UTC)

∈ (with semicolon) I can't actually read with my browser. One should avoid it in writing prose, anyway. Charles Matthews 05:47, 12 May 2004 (UTC)

Birch Swinnerton-Dyer

Thank you for tidying things up and correcting my mistakes on Birch and Swinnerton-Dyer conjecture. I see from your background notes that you did your Ph.D. under Cassels - is that how you know that Cassels was sceptical about the conjecture at first ? I was interested to see that, because I was wondering just how much evidence Birch and Swinnerton-Dyer originally had for the conjecture (obviously it has been put on much firmer ground since). Gandalf61 13:26, May 13, 2004 (UTC)

Yes - personal communication from Cassels. I actually asked him whether they could have got a research grant on the basis of their early results; and he said no. It was some unconvincing plots on log graph paper. Charles Matthews 14:13, 13 May 2004 (UTC)

Universal enveloping algebra

Charles, i made a bunch of edits to Universal enveloping algebra that i would like to get your opinion on when you get a chance.

Spline

I added basic definitions of control points and knots in the spline article. I'm working on a better overview of splines for the article since, currently, the article focuses on interpolating splines (i.e., splines with all control points on the curve). Is there anything else specific that you would like to see in the main discussion of splines? Thanks for the help, jaredwf 12:21, 17 May 2004 (UTC)

Hi. You saw my stub on Elwyn Bellekamp a couple days ago, and I've got a question for you about the article. As it happens, it has little to do with math. Apparently, Berlekamp was a fairly big investor in Ishi Press, and was involved in a number of court cases over it. What I'd like to know is, as a player of Go, have you heard of any of this, and would you consider Ishi Press important enough that the connection is worth a mention in the article? You can read some of the background in the links from this page if you want. Isomorphic 20:43, 17 May 2004 (UTC)

I'd say, don't mention it. Ishi was a small business,it was a tangled bankruptcy with messy legal problems. Nothing for WP there. Charles Matthews 20:54, 17 May 2004 (UTC)

OK. Thanks. Duly noted. I wasn't sure how big a player Ishi Press was in the gaming world. Isomorphic 18:59, 18 May 2004 (UTC)

Possible Massive Copyvio

Please see my note on User talk:Ahoerstemeier about this. Burgundavia 09:45, May 18, 2004 (UTC)

Seems speedy deletion cannot be used, even for such a case, for copyvio. Therefore I'd say it has to be done by persuading the poster to stop.

Charles Matthews 09:52, 18 May 2004 (UTC)

Vector Field

I am currently working on the Vector field page. Do you mind if I merge your Integral curve of a vector field page into the vector field page as an example for the usage of vector fields ? I already started writing on curve integrals over a vector field and I think the topics are closely related and therefore could benefit from being located on the same page (at least now). When the vector field page becomes too big in the near future we could always split the page. MathMartin 16:02, 18 May 2004 (UTC)

Go ahead. In the longer term, I'd like to see stuff about the geometry of envelopes and singular solutions, as a basis for the higher-dimensional cases done with differential forms. Charles Matthews 16:10, 18 May 2004 (UTC)

I do not think I understand the terms envelope and singular solutions in relation to integral curves. Perhaps you could put them into the article vector field ? MathMartin 19:38, 18 May 2004 (UTC)
It's a question of explaining the business with Clairaut's equation, in geometrical terms. This is a special phenomenon.Charles Matthews

I am pretty new to this subject so it would be nice if you could add some tie-ins to the more abstract mathematics (differential forms, vector bundle). At the moment I want to write about vector calculus and curves, surfaces in differential geometry. My motivation and the examples are mostly from physics. What I am trying to say is the basic stuff about vector calculus and differential geometry seems to be missing entirely but some of the more advanced math is present and I want my articles to fit in well with the rest. MathMartin 16:22, 18 May 2004 (UTC)

Well, yes ... it's a basic problem anyway, like jumping 50 years of history from Stokes theorem as Stokes knew it, to the general version. Like jumping from saddle point to Morse theory in one go. I don't really know what the solution is; there are pictures to draw, for one's self; but I don't get that much out of computational approaches with indices. I usually consider that getting the infrastructure in place, covering all the bases, is what one can do. When I pick up Hermann Weyl, for example, it seems that he knows and applies just enough vector calculus for the job; while Hodge is effectively unreadable. Charles Matthews 16:31, 18 May 2004 (UTC)

Mortise and Tennon

Thanks for merging the articles where they belong. I searched Wikipedia for "Tennon" but couldn't find it, so I guessed there is no need to search for "Mortise" and I didn't know what is the right spelling. Nikola 05:54, 19 May 2004 (UTC)

Hi, I appreciate your fancy formatting. I'll have to get a list of all those secret HTML codes. My 1995 book on HTML is a little outdated. Take care! --Tomruen 07:32, 21 May 2004 (UTC)

You're welcome. Charles Matthews 07:34, 21 May 2004 (UTC)


j-function

I know nothing about "j-functions" in the modular function sense, so I thought I'd check with someone more knowledgeable than I first :) Do you think it would be a good idea to disambig j-function with Bessel function, due to the notational similarity? Thanks Dysprosia 11:21, 21 May 2004 (UTC)

It's a good point; but I think (IMX) it's not yet a worrying case for confusion. Those Bessel functions - they need half an alphabet. Charles Matthews 11:25, 21 May 2004 (UTC)

Ok. Sounds good :) Dysprosia 11:55, 21 May 2004 (UTC)

You are right on Whitney

I wanted to say Edmonds introduced matroid into the study of greedy algorithm. But my wording didn't come out right. That mistake has been corrected now. Thanks for pointing it out. Peter Kwok 00:36, 2004 May 23 (UTC)

Cambridge/London meet

Hiya. You put your name on the list at User:Jimbo Wales/2004-06-05, and you mentioned that you are in Cambridge. So am I. I'm wondering if we should meet in Cambridge and go to London together? What do you think? Let me know. — Timwi 21:27, 1 Jun 2004 (UTC)

Could do - I'll take a train around mid-day - haven't decided which yet, and just back from The Coast (Suffolk, that is). Charles Matthews 14:11, 4 Jun 2004 (UTC)