# User talk:Linas/Archive1

## Hello

Hello and welcome to Wikipedia.

When you create a new mathematics article, could you add it to the list of mathematical topics? That alerts interested persons to its existence. Michael Hardy 00:26, 2 Jan 2005 (UTC)

Also, I think you've been using too many capital letters in section headings and links. The style manual explains the conventions. If one person writes a new article titled Gauss map and another writes Gauss Map, often neither suspects the other exists. That's one way in which the conventions are useful. Another is getting links to work correctly. Michael Hardy 00:30, 2 Jan 2005 (UTC)
Example: in Erdös-Borwein constant, I changed "Related Identities" (with a capital I) to "Related identities" (with lower-case), as per the style manual. Michael Hardy 02:56, 2 Jan 2005 (UTC)
OK, I wasn't aware of teh lists.I've been trying to use categories,but can't seem to find a master list of math categories.

Also, you don't need to write [[Q-series|q-series]], since the first letter of a link, unlike the later letters, is case-insensitive, so you can just write [[q-series]]. Also, if you write [[dog]]s, [[logic]]al, [[hyphen]]ated, [[Asia]]n, [[apocrypha]]l, etc., then the whole word, not just the part inside the brackets, will appear as a clickable link, and will link to the article whose title is inside the brackets. The [[A|B]] form of links can be used in cases like [[philosophy|philosophies]] or things like

"Archimedes solved that problem by a [[how Archimedes used infinitesimals | different method]].".

Michael Hardy 22:54, 3 Jan 2005 (UTC)

Welcome!

Hello, Linas/Archive1, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers:

I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. If you need help, check out Wikipedia:Where to ask a question, ask me on my talk page, or place {{helpme}} on your talk page and someone will show up shortly to answer your questions. Again, welcome!

## Planet math

Peace!

Just thinking aloud, I am not quite sure if a good treatise article could make a good Wikipedia article. But this is my own personal opinion. There should be enough room on Wikipedia for everybody's aspirations.

Now, on other things, there is another math free Wiki website, called Planet Math. Unlike Wikipedia, which is written by lay people for lay people, that one is written by mathematicians for mathematicians. It is good if you take a look there it before you write a new article on Wikipedia, they might already have it.

Since both Wikipedia and Planet Math are under GFDL (GPL for documents), thinks are transferable back and forth. There is some discussion about that now at Wikipedia talk:WikiProject Mathematics. Take a look. (By the way, it is good to have that page on your watchlist, interesting things are going on there sometimes). 04:17, 29 Jan 2005 (UTC)

Yes, well planet math is lame, which is why I'm here at the wikipedia. For the various articles I've looked at, wikipedia has both a deeper and broader coverage of math than planet math. As to tretises, the stuff that I've been adding is trivial and trite compared to much of the deep and complex math that can be found on wikipedia. So I am not sure what you are refering to when you say 'tretise'. For me, wikipedia is a tool. Most of the math I do goes onto my personalweb site;the stuff I put on wikipedia is just various margin notes I encounter during my reading.
I will consider decamping to Planet Math.linas 05:25, 29 Jan 2005 (UTC)
I did not imply your last sentence. Sorry! There is room for everybody here. Oleg Alexandrov | talk 05:36, 29 Jan 2005 (UTC)

I am happy you will not leave us. But for the record, you did misunderstand me. Look where we intersected:

Oh, and you did not pay attention to what I mentioned you shoud, the talk about planet Math which was going there. I am now in a project to make a list of every single Planet math article, so that people here can check and compare what we have here and what they have there. Oleg Alexandrov | talk 16:21, 29 Jan 2005 (UTC)

Oleg, ... I think you are still missing my point. If you want a nice verbal loosey-goosey treatment for characters and character groups, then go read either character theory or Dirichlet characters. These articles use laymans terms and have almost no usable formulas in them. These "laymans's" articles should no doubt be expanded,and further edited for style, and etc. and I invite you to do that. However, at some point, if wikipedia is going to serve as a useful reference to someone who actually needs to "do" math, then an actual reference with actual formulas and equations is needed.
You have a point. Just as a very humble suggestion which you should feel free to ignore: some more motivation, applications, and examples, would not hurt even in character group. All up to you.
There is something else I realized by the way. I was trying to be too controlling of what you write (I can count 2 instances of this). That is hopeless, whether I have a point or not. So I appologize. Oleg Alexandrov | talk 19:11, 29 Jan 2005 (UTC)
What I am trying to propose is that there is room for two types of articles on wikipedia: the "intro to calculus" type articles, which use lots of words,pictures and diagrams,and are written in plain english, and are oriented at the layman, and also an "advanced calculus" type article, which cuts the bullshit and just plain lists various integrals, without all the verbiage.
Thus, I suggest that character theory remain simple and plain and non-intimidating, while the more advanced character group provide the actual details. Similarly Dirichlet character can be a gentle introduction whereas the hardcore Hurwitz zeta function covers exactly the same topic, but in depth.
I'll happily accept suggestions for article naming conventions. For example, we could move character group to character theory (reference) and link character theory to it for the advanced reader. However, I do not want to change the stye: the theorem-proof style is much more eloquent and easier to understand than pedestrian flowery-talk, if you are actually a practicing mathematician.
Similarly, I can move Hurwitz zeta function to Dirichlet character (reference) and re-insert a simpler, low-brow Hurwitz zeta function for the non-technical reader, and then have the two link to each other.
Would this be an acceptable solution to the problem of how to cover both simple and advanced topics at the same time,for the same subject? linas 18:47, 29 Jan 2005 (UTC)

Yes. I leave the details up to you. I am very happy we get to understand each other, and that you started taking a more "big picture and purpose" view on things. Good luck. I will give suggestions when I have any. Oleg Alexandrov | talk 19:13, 29 Jan 2005 (UTC)
P.S. yes, I'll move the modular arithmetic article. Should I move or should I copy? I'm not sure I know how to fork and retain edit history correctly. linas 19:05, 29 Jan 2005 (UTC)
Can you hold on with that a bit please. In an hour or two I will get to that article, I will trim it a bit (not a lot), then I will contact you for more details. Oleg Alexandrov | talk 19:13, 29 Jan 2005 (UTC)
You cannot keep hold on the edit history. You need to start anew. Oleg Alexandrov | talk 21:36, 29 Jan 2005 (UTC)

## Elementary vs. non-elementary

I just changed modular arithmetic. I did not know how to keep a lot of your facts, and still make it not stray too far. So I removed most of the stuff, but I might later put some of it back (I need to think more).

I think it would be too much to introduce a character theory (reference) thing. But I don't know. There are no perfectly clear and rigid way to separate hard math from easy math. It is all a matter of opinion, style, and taste. And these depend on people and change in time. For example, I like the Hurwitz zeta function article the way it is. It sort of flows along nicely, which I did not feel about character group. But that's just me.

I will not say more. Again, I had been saying way too much. And honestly, all these arguments took a tremendous amount of my time and energy too. Good luck. I will keep on doing small fixes, but no more debate. Oleg Alexandrov | talk 21:34, 29 Jan 2005 (UTC)

## Question

Hi Linas. I left for you a message on Talk:Upper half plane. By the way, if you would like to be kept updated with developments concerning your edits, checking the watchlist often is a good resource. Cheers, Oleg Alexandrov 18:59, 7 Feb 2005 (UTC)

## New Mathematics Wikiportal

I noticed you've done some work on Mathematics articles. I wanted to point out to you the new Mathematics Wikiportal- more specifically, to the Mathematics Collaboration of the Week page. I'm looking for any math-related stubs or non-existant articles that you would like to see on Wikipedia. Additionally, I wondered if you'd be willing to help out on some of the Collaboration of the Week pages.

I encourage you to vote on the current Collaboration of the Week, because I'm very interested in which articles you think need to be written or added to, and because I understand that I cannot do the enormous amount of work required on some of the Math stubs alone. I'm asking for your help, and also your critiques on the way the portal is set up.

Please direct all comments to my user-talk page, the Math Wikiportal talk page, or the Math Collaboration of the Week talk page. Thanks a lot for your support! ral315 02:54, Feb 11, 2005 (UTC)

## Great new pictures, Linas!

Hi. Love the pictures. I've often heard g2 and g3 referred to as "semi-fractal" functions of q and now I see why. Great stuff!

best

Robinh 10:21, 14 Feb 2005 (UTC)

## Stone von Neumann

I made the corrections, I hope I got them right. I was calling P, Q exactly the opposite of what they should have been called, so the changes were easy (famous last words).CSTAR 05:20, 2 Mar 2005 (UTC)

## Modular group

In response to your question on my talk page - the modular group has a very specific definition - it is the group of Möbius transformations with ad-bc=1 (see this Mathworld page for example). It is isomorphic to PSL(2,Z). Members of the modular group are sometimes represented by matrices with determinant 1 (i.e. members of SL(2,Z)), but the representation is not unique because the matrix A represents the same transformation as the matrix -A. I can't see how members of the modular group can be represented by matrices with determinant -1 - which modular group member corresponds to the matrix

${\displaystyle {\begin{pmatrix}0&1\\1&0\end{pmatrix}}}$

for example ? This is why I changed the statement in Fibonacci number "this matrix has a determinant of +1 or -1, and thus it is an element of the modular group" to "this matrix has a determinant of +1 or -1, and thus it is a 2x2 unimodular matrix". Gandalf61 09:28, Mar 4, 2005 (UTC)

Linas - saw your reply on my talk page. You say "The modular group S*L(2,Z) is defined to have determinant having plus or minus one". I take this to mean that you believe the modular group is defined to be the group of 2x2 integer matrics with determinant +1 or -1. Unfortunately, this is wrong. The modular group is defined to be a certain group of Möbius transformations. It is isomorphic to PSL(2,Z), which is in turn isomorphic to SL(2,Z)/{I,-I}. It is definitely not isomorphic to S*L(2,Z). If you think it would be informative to add a link to modular group in the Fibonacci number article then you can put the link in the "See also" section. But to imply that the modular group is the same as the group of unimodular matrices is simply incorrect.

Just wondering, are you going to do anything about that article? Oleg Alexandrov 21:53, 6 Mar 2005 (UTC)

Replied on Talk:Advanced modular arithmetic theory. Oleg Alexandrov 05:23, 21 Mar 2005 (UTC)
PS I am happy with modular arithmetic the way it is. I do not think it is biased towards rings and neglects groups. I mean, come on, all it says that you can add conruence classes, you can multipy them, and, by the way, that is called a ring. I agree with you that some compromises had to be made for that article, but for an elementary, general purpose so to speak, article, what is there is a good selection. Oleg Alexandrov

## WP:PMEX

You might want to add your name to the list of participants. Also, when you change the status, please sign on the next line: use ::~~~~ as is the standard, as it helps to eyeball what has been done easier than if you put it inline. Thanks. CryptoDerk 23:16, Mar 12, 2005 (UTC)

I added an inuse tag to the article and yet you continue to edit it. Please stop, I'm trying to fix all the mistakes. CryptoDerk 23:30, Mar 12, 2005 (UTC)
Sorry. I didn't see your tag. I was in the middle of working on this, should I not bother? Do you want me to help or do you think it might be better that I didn't? linas 23:33, 12 Mar 2005 (UTC)
No biggie. See this for a list of things that needed to be corrected. With the status, please stick to the seven messages (Needs to be copied, Copied, Needs to be merged, Merged, WP article adequate, WP article more complete, Not needed on WP) and then on the line with your signature feel free to put a comment like "minor merge needed". Also, watch the spelling. Proper formatting and spelling assure that those who are working on statistics will be able to find everything quickly, and Oleg is working on a script for automatic updating of the lists, and I imagine it won't be flexible in terms of spelling and format errors. Please continue to contribute to the project though, we all appreciate it! CryptoDerk 23:40, Mar 12, 2005 (UTC)

Regarding the bold/italic thing, perhaps, although all the entries up to now have been formatted with bolded statuses. You might want to ask on the talk page of WP:PMEX. It mostly depends on how Oleg is doing his script. Either way, bold, italics, or nothing, people can do a "find" and locate things that need attention. CryptoDerk 23:46, Mar 12, 2005 (UTC)

## Eisenstein's criterion

Thanks for pointing out the proof was there but not the criterion itself. I figured out why it was missing in that section. You see, on PlanetMath, they had the proof of the Eisenstein's criterion classified in

AMS MSC: 11C08 (Number theory :: Polynomials and matrices :: Polynomials)

and

13F15 (Commutative rings and algebras :: Arithmetic rings and other special rings :: Factorial rings, unique factorization domains)

while the article itself was classified only in 13F15. That was stupid of them. Now I added Eisenstein's criterion by hand to the Number theory. Oleg Alexandrov 02:37, 13 Mar 2005 (UTC)

## Spelling

I took a passing look at some of the articles you list on your page. I found a somewhat big number of spelling mistakes (some things I corrected were actually correct British variants, I changed them for uniformity, but most were true mistakes). I have good reasons to believe that a good chuck of them were introduced by you (I looked at some diffs). I hope you don't mind if I suggest that you use a spell checker. You could try to take a look at Wikipedia:Text editor support to see if you find any of those options attractive. Thanks.

(And thanks for your help with copying things over from PlanetMath). Oleg Alexandrov 22:14, 20 Mar 2005 (UTC)

Linas, you have been here for three months now. So you are certainly not a novice, and I am sure you care about Wikipedia. Why then don't you use a spell checker? I mean, come on, all of us make mistakes, all of us misspell things every now and then. But, from my experience, virtually any edit of yours is guaranteed to have some misspellings (the latest examples are pullback and Hopf-Rinow theorem).
Now, misspelling is not wrong in itself, and neither you nor me are native speakers. But then please spellcheck after yourself. See Wikipedia:Text editor support about how to pop up an editor using MozEx to spellcheck. You are a computer person, you should have no problems installing a Mozilla extension. I can give more tips about that if you wish. Oleg Alexandrov 20:32, 2 Apr 2005 (UTC)

## New Mathematics Project Participants List

Hi Linas.

In case you didn't follow the discussion on Wikipedia talk:WikiProject Mathematics here: Wikipedia talk:WikiProject Mathematics#Reformat of Participants list, I'm writing to you to let you know that I've converted the "WikiProject Mathematics Participants List" into a table. It is now alphabetical, includes links to the participant's talk page and contribution list, and has a field for "Areas of Interest". Since your name is on the list, I thought you might want to check and/or update your entry.

Regards, Paul August 16:41, Mar 22, 2005 (UTC)

P.S. Thanks for all your good work on the PlanetMath Exchange project ;-)

## Bernoulli polynomials

Hi Linas. Thank you for your contributions to that article, it indeed looks neat. I have just one suggestion. In the second half of the article considerable time is spent on Euler polynomials and numbers, and no explanation is given on why these have anything to do with the Bernulli polynomials, and why they are mentioned to start with. Could you rectify this when you have time? Thanks. Oleg Alexandrov 15:08, 26 Mar 2005 (UTC)

## Appeal for math/physics help

Hi,
I found your name in the edit history at Legendre polynomials. You seem to have the mathematical knowledge to help me with a certain undertaking that I've had on my list for many moons. The undertaking is a complete rewrite of Electron configuration. I think I'm competent to do the better part of the work, with the notable exception of a few cryptic comments in the first paragraph after the heading "Angular momentum". If you would be so kind as to make sense of them and reproduce their meaning (in a more thorough and clear fashion) in some other article, such as Atomic orbital, I would be much obliged and would begin the rest of the task forthwith. I've watchlisted your talk page, so you may respond right here. --Smack (talk) 04:39, 28 Mar 2005 (UTC)

Hi Smack, Not sure exactly which parts are 'cryptic'. The reference to the legendre polys could be cut, it plays no particular role in this article. The link to spherical harmonics should clearly be kept; the only "real" way to understand the atomic orbitals is through the spherical harmonics. The traditional mechanism for understanding atomic structure is by solving the Schroedinger equation for a 1/r^2 potential (the electric field of the nucleus). When written in spherical coords, the Schreodinger equation splits into two pieces, the radial part (involving only r and l(l+1)) and the "shell" part (involving only the angles). The solution to the "shell" part are the spherical harmonics (which are built out of Legendre polys). Makes sense now? What part was unclear? linas 05:52, 28 Mar 2005 (UTC)
OK, I just re-wrote the intro to Electron configuration, maybe it is a bit more clear now? Edit away! and Good Luck ! ... linas 06:43, 28 Mar 2005 (UTC)
I found the Legendre-polynomial bit cryptic, but maybe that was inevitable given that I don't know the relevant math. When I have a good bit of free time, I'll have another go at it. Thanks for the help. --Smack (talk) 04:08, 29 Mar 2005 (UTC)
OK, in the end, the math isn't that hard; let me see if I can do this in three sentances. Look up Laplacian then go to edit history, and look up laplacian as it was on 6 march. Look at the formula for "laplacian in spherical coordinates." Now drop all the terms that don't have the angles θ or φ in them. What's left is the sphereical part; the spherical harmonics are the solutions to that. The spherical harmonics are mostly just the associated legendre polynomials, times an easy peice. -- And that is all, nothing really deeper than that. linas 05:30, 29 Mar 2005 (UTC)

See talk:Analytic function (Linas forgot to sign)

I replied there too. Oleg Alexandrov 19:24, 9 Apr 2005 (UTC)
PS I like it that you check your watchlist more often. After all, one better keep a frequent interest in the articles one created. Oleg Alexandrov 19:24, 9 Apr 2005 (UTC)
I wrote more there. Oleg Alexandrov 20:30, 9 Apr 2005 (UTC)
I wrote more to address your concerns. I understand you are busy. I am busy too. I will not change analytic function for a couple of days, to give you more time to think about things. Oleg Alexandrov 22:05, 9 Apr 2005 (UTC)

## The Laplacian article

I know you check your watchlist more often recently, but I decided to post this here just in case. I replied to you on Talk:Laplace operator. Cheers, Oleg Alexandrov 23:14, 18 Apr 2005 (UTC)

I wrote more at Talk:Laplace operator#Remark about Dalambertian. Oleg Alexandrov 16:58, 27 Apr 2005 (UTC)

## moving articles from Category:Physics

I'm not sure I agree with some of your moves out of Category:Physics. Some are appropriate, although I kind of liked that things your average college sophomore with a physics interest had seen were all in that category, but a good number don't fit into one sub-category. For instance: the Zeeman effect is covered in your average sophomore quantum physics class, but it's now hidden in Category:Atomic physics. Similarly, you've moved wave packet, a general idea in physics that just happens to be a focal point in quantum mechanics, into Category:Quantum mechanics, despite its applicability in any field of physics involving waves.

So just a heads up that I'm going to tinker with it some more. You clearly think that Category:Physics should be less cluttered, so I'll try to avoid putting them back there unless I think that's the only reasonable thing to do. --Laura Scudder | Talk 17:16, 1 May 2005 (UTC)

I said I'd respect your desire to move things out of the category. So far I've only moved potential well back in as it would have to be in too many sub-categories because all physics is about potential wells. Right now I'm just adding sub-categories where appropriate to make the article possible to find by someone who knows something about it. --Laura Scudder | Talk 17:27, 1 May 2005 (UTC)
I like the idea about an introductory physics category. Especially since we've got things like apparent weight floating around next to intimidating things. --Laura Scudder | Talk 17:46, 1 May 2005 (UTC)

## List of Lithuanian rulers

I need more info on the pre-Mindaugas rulers at the Talk:List of Lithuanian rulers. Could you help? Halibutt 21:40, May 4, 2005 (UTC)

## Transmission, not distribution

Hello. Could you please create a category Electric power transmission and move the HVDC articles to it? In a couple of hours you've undone days of my tedious hand editing to get rid of the previous erroneous categorization...you obviously have better tools for doing this than I have. Speaking of "distribution" in the context of HVDC is just wrong - it's not even consistent with the article electrical distribution. HVDC is used for bulk transmission only, and not for distribution. Thanks. --Wtshymanski 22:33, 8 May 2005 (UTC)

Oh, thanks - I see the change is in progress! --Wtshymanski 22:48, 8 May 2005 (UTC)
Thanks for the quick action on the re-categorization whirlwind - I'm sure the confusion has been reduced by your efforts. --Wtshymanski 01:40, 9 May 2005 (UTC)
No problem. I think finding "pliers" in category physics or something like that is what pushed me over the edge ...:) linas 01:44, 9 May 2005 (UTC)
I can see how that would make you snap. Do you have software to assist in the categorization or are you instead a lighting-fast typist? A dial-up connection is OK for some things but I find it slow for multiple changes. --Wtshymanski 01:48, 9 May 2005 (UTC)

## Reverts

Hi Linas. I think you complained to CSTAR about unexplained reverts, but now are doing the same thing. I agree with you about the reversions in symmetry and Erdos number, but if you don't explain what you are doing, you could be having big arguments with R. Koot who by the way did a lot of work in categorizing the math articles (whether you agree with the choices of this person or not). So, be more explicit. :) Oleg Alexandrov 05:58, 14 May 2005 (UTC)

Ah, well, you know, *I* don't need to explain what I'm doing, its the *other people* who need to do this. :) As it happens, I am deeply unhappy with User:R.Koot's edits. I thought the math category looked pretty elegant, and here I come back to look, and its like someone used dull scissors to cut all the hair off the doll. Gack! linas 06:06, 14 May 2005 (UTC)
I was trying to say that if you don't explain things now, you might get into an edit war, be forced to explain things later, and get yourself bad relations with a well-meaning person, in this case R. Koot. But that's your problem. :) Oleg Alexandrov 06:16, 14 May 2005 (UTC)
Never mind, it took me a while to get the sarcasm in your message. I think you better talk to R. Koot. Oleg Alexandrov 06:16, 14 May 2005 (UTC)
Also see some discussion at the Wikipedia talk:WikiProject Mathematics about this. Oleg Alexandrov 06:16, 14 May 2005 (UTC)

## Weierstrass and Theta

Hi Linas

yes, terminology for theta functions is pretty wild and fabulous. Even Abramowitz and Stegun complain of a "bewildering" variety of notations, and point to a table in Whittaker and Watson that is itself a pig's ear. And I can be sure that if A&S find it bewildering, then _I_ will find it even worse. And things are worse than they were in the 1960s: new notations have surfaced since.

I favour the hard-line approach: everything consistent with A 'n' S.

Your suggestion about hiving off the invariants is splendid: the article is getting too long. I like the thing where the article says "(main article: whatever)".

Very best wishes

Robinh 15:04, 18 May 2005 (UTC)