User talk:Katzmik

From Wikipedia, the free encyclopedia

Welcome!

Hello, Katzmik, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are some pages that you might find helpful:

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:Questions, ask me on my talk page, or ask your question and then place {{helpme}} after the question on your talk page. Again, welcome!

And don't forget, the edit summary is your friend. :) – Oleg Alexandrov (talk) 15:24, 19 April 2007 (UTC)

1 What is the relevance of Systolic geometry to Hyperbolic geometry?
2 Reply to JRSpriggs
3 Figure in Systolic geometry
4 Peacock Terms
5 Using links instead of instructions
6 List of inequalities
7 Too many Wirtinger's inequalities
8 Fixing links to new disambiguation page
9 Klein's quartic
10 Watchlist mysteries
11 Liouville eqns
12 Hermite constant
13 AfD nomination of Systolic geometry for a beginner
14 Reply at User talk:Tgies
15 Up-sizing Tex

[edit] What is the relevance of Systolic geometry to Hyperbolic geometry?

What is the relevance of Systolic geometry to Hyperbolic geometry? You have put this link into Hyperbolic geometry twice. To me it looks like link spam. What do they have in common beside the fact that they are both called "geometry"? If you do not give me a good reason, I will remove it again. JRSpriggs 07:32, 24 April 2007 (UTC)

[edit] Reply to JRSpriggs

I am sorry I am not exactly sure what format to answer you in. If you see this message, could you please indicate your email address so I can write to you? My email address can be found at the "Website for systolic geometry and topology" that you can easily find with google.

You may reply here. JRSpriggs 09:27, 24 April 2007 (UTC)

OK. First of all, I would like to apologize about duplicating the link to hyperbolic geometry. I added a number of links in the past couple of days to the new page "Systolic geometry", and did not notice that you had removed the link from hyperbolic geoemetry.

Second, if you find the link is inappropriate, I certainly have no objection to removing it.

The reason I placed the link there in the first place is because there is considerable intersection today between hyperbolic geometry and systolic geometry. The hyperbolic bibliography at the "Website for systolic geometry and topology" contains over three dozen articles, including such hyperbolic heavyweights as C. Adams and A. Reid.

I would be glad to provide further details if you are interested.

The question is not whether hyperbolic geometry is relevant to systolic geometry. The question is whether systolic geometry is relevant to hyperbolic geometry. What does systolic tell us that helps us to understand spaces with constant negative curvature? JRSpriggs 10:21, 24 April 2007 (UTC)

I would be glad to answer this question. If you don't mind, I would prefer to continue this discussion via email. Otherwise I have no objection to removing the link if it bothers you. Katzmik 15:21, 25 April 2007 (UTC)

Can I just say that there has been a misunderstanding here. Your edits are welcome. Charles Matthews 16:56, 25 April 2007 (UTC)

I have restored your link at hyperbolic geometry that JRSpriggs incorrectly deleted. He means well, but has for some reason mistaken your work for some of the junk that is often added to wikipedia. Your additions are a big improvement to the article, and are most welcome. R.e.b. 17:12, 25 April 2007 (UTC)

Indeed, welcome to Wikipedia! Wikipedia:WikiProject Mathematics is always thrilled to get professional attention. I invite you to join the conversations on the talk page Wikipedia talk:WikiProject Mathematics, where your arrival was noticed and breifly discussed. linas 23:55, 26 April 2007 (UTC)

[edit] Figure in Systolic geometry

Hi, I'm trying to understand the new Systolic geometry page, and the figure has confused me. Does it show the systole of the surface? Is it importact that its a geodesic? The caption probably needs a rewrite as Fig 8 does not have much meaning here. --Salix alba (talk) 07:18, 26 April 2007 (UTC)

Thanks for your interest. The figure is an illustration of one of my favorite results in systolic geometry, namely Gromov's filling area conjecture and its proof in the hyperelliptic case. If you let me know what your background is, I will try to explain the result and the figure. I would feel more comfortable doing this via email as not all of this discussion may be relevant to the six billion readers of wiki ☺ -MK

Most readers just read the articles, not the talk pages and especially not the user talk pages. JRSpriggs 09:22, 26 April 2007 (UTC)

The best place for discussion on the article would be Talk:Systolic geometry which is the prefered place on wikipedia. My main interest is in an figure illustrating the esential point of Systolic geometry.--Salix alba (talk) 10:00, 26 April 2007 (UTC)

I agree. The "systolic geometry" page is certainly not in its final form (it only went online this week!) I am certainly pleased with the interest it generated. I am planning to expand it, both by including further details on systolic hyperbolic geometry, and a clarification of the significance of the figure-8 illustration. I will try to check the user talk page periodically. -MK

[edit] Peacock Terms

What's a peacock term you mentioned on the systolic geometry page? MK —The preceding unsigned comment was added by Katzmik (talk • contribs) 11:17, 26 April 2007 (UTC).

See Wikipedia:Avoid peacock terms --Brentt 20:41, 26 April 2007 (UTC)

Thanks for the reference. I looked over the peacock instructions. Of course, they are very appropriate and helpful. Clearly, the importance of a wiki topic has to be explained rather than merely asserted. The particular term I used was used for a different purpose. Namely, all French readers (even non-mathematicians!) know who Rene Thom is, and have a feeling for why someone would want to listen attentively to his every utterance, as Marcel Berger did. To English readers, on the other hand, he is less familiar. I therefore used the peacock term "venerable" in order to make the ensuing discussion plausible to an English-speaking layman (the details can be found by following the link to Thom's wikipage).

I don't think it is essential to put it back in, but in the future well-meaning editors should try to follow the spirit of the law and not merely the letter.

Katzmik 08:32, 27 April 2007 (UTC)

[edit] Using links instead of instructions

Several days ago, you left a message for me which included "For the time being I did not place it in wikipedia, but rather on my 'Website for systolic geometry and topology'. If you are curious to see it, go to the website, click on 'subfields', then click on 'systolic hyperbolic geometry'.". Following such instructions is rather difficult. I suggest that in the future, you instead give a direct link to the page in question. Somewhat like this:

your main page

http://www.cs.biu.ac.il/~katzmik

website for systolic geometry and topology

http://www.cs.biu.ac.il/~katzmik/sgt.html

subfields page

http://www.cs.biu.ac.il/~katzmik/sgtdirectory/subfields.html

systolic hyperbolic geometry page

http://www.cs.biu.ac.il/~katzmik/sgtdirectory/hyperbolic.html

Then it would be much less work for the readers to find it and they will be more likely to actually go there rather than giving up. JRSpriggs 06:58, 30 April 2007 (UTC)

Good idea. Now that you mention it, it seems the obvious thing to do, but I overlooked it! Thanks very much. Katzmik 11:01, 30 April 2007 (UTC)

[edit] List of inequalities

Hello. I just added a couple of pages that you created to the list of inequalities. If you know of others that should be added, could you do that? Michael Hardy 17:44, 30 June 2007 (UTC)

Thanks. I was not aware of the list of inequalities. I have a couple of other candidates, namely some inequalities of Gromov's. Katzmik 13:46, 1 July 2007 (UTC)

[edit] Too many Wirtinger's inequalities

I think something should be done about the fact that Wirtinger's inequality and Wirtinger's inequalities are on two different topics but have names so similar to each other that the similarity will cause confusion. Possibly the best way to handle it is to use the "move" button and in one case write Wirtinger's inequality (blah) and in the other, Wirtinger's inequality (blah), for two different appropriate values of "blah". Then "Wirtinger's inequalities" could redirect to "Wirtinger's inequality" which would then be made into a disambiguation page. After that, all the links to the old titles would have to get suitably directed. What do you think? Michael Hardy 22:28, 10 July 2007 (UTC)

very good idea. Could you please do that, since you are more experienced with creating disambiguation pages and the like? The current Wirtinger's inequality could be called Wirtinger's inequality for functions. The site I created is Wirtinger's inequality for 2-forms (namely, alternating, or exterior, 2-forms). It is usually stated for the standard symplectic 2-form, but in fact there is a suitable generalisation to arbitrary 2-forms, which is what Gromov used in his proof of the systolic inequality for complex projective space. Most of the literature on this Wirtinger's inequality uses the special case of the symplectic 2-form, and the literature is rather extensive, though it is not (yet) reflected in wiki. Katzmik 11:50, 11 July 2007 (UTC)

P.S. The inequality for 2-forms is usually referred to in the literature as the Wirtinger inequality, not Wirtinger's inequality. If this is compatible with wiki standards, it may be preferable to use that term. Katzmik 11:52, 11 July 2007 (UTC)

[edit] Fixing links to new disambiguation page

Wirtinger's inequality is now a disambiguation page. The next task is to go to that page, click on "what links here", and in each article that links to the disamiguation page, link to the appropriate article. Michael Hardy 02:25, 12 July 2007 (UTC)

...OK, I think that may be essentially done now. Michael Hardy 02:36, 12 July 2007 (UTC)

Thanks. Katzmik 11:09, 12 July 2007 (UTC)

[edit] Klein's quartic

This page notes that the Klein quartic is Γ(7)\H² (search for "congruence" on that page). See also the first sentence of this PDF, or Google "klein quartic congruence". You're completely right that it's a subgroup of PSL(2,Z), rather than PSL(2,R), and I've made that change to the article. Tesseran 19:50, 31 July 2007 (UTC)

There is an error here. A subgroup of PSL(2,Z) would give a complete surface, but not a compact one. To get the compact Klein quatric (as opposed to an affine slice), one needs a more elaborate arithmetic set-up. Katzmik 09:07, 1 August 2007 (UTC)

Incidentally, if you read THE SECOND CLAUSE of the first sentence of Agol's pdf at this PDF, you will notice that he is more careful about cusps. Katzmik 15:38, 1 August 2007 (UTC)

[edit] Watchlist mysteries

Jitse, could you please comment on how the personal watchlist works? For some reason items keep disappearing from my watchlist. For instance, your edit at Bolza surface appeared on my watch list, but only for a split second, and it is not there anymore. Katzmik 11:15, 6 August 2007 (UTC)

That's strange. I can think of only two explanations, neither of which seems likely. The first one is that you somehow removed the page from your watchlist. You can view a list of articles on your watchlist by first clicking my watchlist (in the upper right hand corner) and then view and edit watchlist; the URL

http://en.wikipedia.org/w/index.php?title=Special:Watchlist&action=edit

should take you there directly. The second explanation is that you have "Hide my edits from the watchlist" turned on in your preferences and looked at the watchlist after you made an edit to Bolza surface following my edit. As the watchlist only shows the last edit to an article, nothing will be shown in this case. You can check that by clicking my preferences (again in the upper right corner) and then the Watchlist tab. The only other hint I can give is to read Help:Watching pages and see whether that may help you understand what's happening. -- Jitse Niesen (talk) 12:25, 6 August 2007 (UTC)

I saw this thread by accident and wanted to share an insight: another thing that could affect a watchlist is robots modifying an article. Frequently, the watchlist will not show bot edits (this feature can be turned on and off); as a result, if a bot modifies an article right after a human, the human's edit will be struck out, but the bot's edit will not appear. Typically, this happens if someone forgets to sign a comment on a talk page, and one of the signing bots does it for him, or if a bot archives part of a page (a frequent situation at WT:WPM) Could this be happening in your case? Arcfrk 22:40, 6 August 2007 (UTC)

[edit] Liouville eqns

It is the same, I've checked with Barbashov, Nesterenko book. String4d 10:09, 13 August 2007 (UTC)

I have Polyakov's original paper and its discussion in Barbashov, Nesterenko book. Polyakov shows that string theory at D<26 contains a field described by Lagrangian $L=(\partial_{\mu}\varphi)^{2}/2+\mu^{2}e^{\varphi}.$ Its classical equation of motion is $-\partial^{2}\varphi+\mu^{2}e^{\varphi}=0.$ It is equivalent to Liouville equations after variables change $\varphi=2\log f,\ \mu^{2}/2=K.$ String4d 16:51, 14 August 2007 (UTC)

[edit] Hermite constant

Hello Michael,

I appreciate your interest in Hermite constant. A note about notation: I agree with the general principle that low-level commands at the html level are preferable to fancy math environments if the latter can be avoided. However, the square root of γ that currently appears at Hermite constant really does not look like a proper square root. There is a way of making an overline in html but I wonder if it is worth the time. In other words, one should either use proper html, or a math environment, it seems to me. Katzmik 07:51, 16 August 2007 (UTC)

I was never acting on a general principle that html is better than TeX; I was acting on the fact that TeX looks bad in some contexts where bad mismatches in alignment and size happen. Michael Hardy 03:35, 6 September 2007 (UTC)

[edit] AfD nomination of Systolic geometry for a beginner

I have nominated Systolic geometry for a beginner, an article you created, for deletion. I do not feel that this article satisfies Wikipedia's criteria for inclusion, and have explained why at Wikipedia:Articles for deletion/Systolic geometry for a beginner. Your opinions on the matter are welcome at that same discussion page; also, you are welcome to edit the article to address these concerns. Thank you for your time. Do you want to opt out of receiving this notice? tgies (talk) 12:55, 29 May 2008 (UTC)

I responded at the deletion page. Katzmik (talk) 13:34, 29 May 2008 (UTC)

[edit] Reply at User talk:Tgies

Hello, Katzmik. You have new messages at Tgies's talk page.
You can remove this notice at any time by removing the {{Talkback}} template.

[edit] Up-sizing Tex

TeX is the display language which uses "<math>...</math>" and is described at Help:Displaying a formula. You may have noticed that sometimes the formulas displayed with TeX are large (e.g. " $A_M: M \to J_1(M)\!$ ") and sometimes they are small (e.g. " $A_M: M \to J_1(M)$ "). You can change those which are small to the large size by inserting "\!" or "\,". The "\," also adds a short blank space. It is our convention that when a TeX formula is displayed on a separate line it will be large and indented. In particular, Systolic geometry#Relation to Abel-Jacobi maps has several formulas which need to be fixed. JRSpriggs (talk) 10:37, 31 May 2008 (UTC)

See also ebooksgratis.com: no banners, no cookies, totally FREE.