# User talk:Yakovenko

Hi, welcome aboard of EoM.

I just checked and found 331 EoM pages with at least one of your favoured keywords: "singularities, limit cycles, normal forms, invariant manifolds, foliations"

If you want I could include here a list of links to those pages. --Ulf Rehmann 12:41, 15 April 2012 (CEST)

I will gradually learn the habits of the Wiki community. The first question is how to post answers/comments in the "Talk" pages: this one I do manually, but hopefully there should be some interface for such conversations (threaded or not).
Thanks -- Sergei.
Well, see below. It is probably not a good idea to let this spam your talk page so maybe you put it into a separate page. I have something similar on my user page, a bit pre-sorted by now, but was started with a list like the below.
For editing, you can use your favoured editor, I have given hints on the help page, look for "It's all text".--Ulf Rehmann 15:29, 15 April 2012 (CEST)
For the pages below, I have applied a program which inserts MR and ZBL numbers automatically. It does make mistakes, in particular sometimes it proposes too many entries, so please check. --Ulf Rehmann 19:01, 15 April 2012 (CEST)

331 files containing one of these keywords: "singularities|limit cycles|normal forms|invariant manifolds|foliation"

Sergei, you'd better use the "MSCwiki" template on your userpage; the "MSC" template gives a category to your userpage, which should not happen; as far as I understand, only articles should have categories. By the way, if you want to only mention a category, you can do it like this: Category:Ordinary differential equations. --Boris Tsirelson 21:56, 5 May 2012 (CEST)

Done. Thanks! BTW, I still hesitate how to deal with multiple "Primary" classification. Ulf corrected me that MSN indeed requires only one primary class, so apparently either my memory betrayed me, or the editors of MR did the last choice for me...
Yes, I also feel such a problem. I knew that only one primary is allowed by MR (no, it is not a novelty), but it makes some troubles. Sometimes I gave a secondary class only because I could not give another primary. But I was prepared to have troubles; every classification makes troubles (is there some Goedel-type theorem for it?);
No, Boris, it's Zermelo: Your problem is discussed here:) --Ulf Rehmann 10:42, 6 May 2012 (CEST)
?? --Boris Tsirelson 13:38, 6 May 2012 (CEST)
Oh well, for every EoM page $p$ you have the set $C(p)$ of possible classifications, now by Zermelo you know there is a function $C(p) \mapsto c_p\in C(p)$ to pick one to get $p\mapsto c_p$, however, Zermelo is not constructive... (Sorry Sergei for spamming your talk page with nonsense... feel free to delete this). --Ulf Rehmann 15:01, 6 May 2012 (CEST)
and they are much harder (at least for me) when I finish a paper; sometimes I cannot find any appropriate class at all. Encyclopedic articles are better in this aspect, and no wonder: they describe existing topics, while papers can also introduce new topics. --Boris Tsirelson 07:40, 6 May 2012 (CEST)
Boris, my hesitation comes from pages which contain an intrinsic disambiguation. For instance, the Node (unfinished job) may mean either nodal singularity of a curve, a singularity of a vector field, a point in the interpolation scheme etc. Of course, one could write separate pages and give them the different codes, yet this would result in atomization of EoM. I personally prefer the Britannica-style where a page (article) is a subject for reading rather than a few lines of dictionary-like definition so characteristic of БСЭ and Webster. In this respect it would be better to write longer pages if they have some common math genetics. -- Sergei Yakovenko 07:47, 6 May 2012 (CEST)
You may as well put in two or more MSC lines. I used the MSN conditions for the template, because this way I could make use of the capabilities of the MSN parser for the classification semantics. I wished the MSCwiki would offer such a parser as well. --Ulf Rehmann 10:42, 6 May 2012 (CEST)
I also like "a subject for reading rather than a few lines of dictionary-like definition". But it does not mean that I like "pages which contain an intrinsic disambiguation". As for me, several closely related topics (with quite different names) coexist well in an article; but weakly related topics with similar (or even identical) names do not. For example, "Measurable space" is rather long; but "Measure algebra" is a disambiguation page, and does not need MSC classification. --Boris Tsirelson 13:38, 6 May 2012 (CEST)
Probably, I need to overcome some newly acquired phobia: once I learned that only Ulf has the privilege to delete pages, I grew very reluctant to create new pages. Thus, if I see a page like Isotopy, I would add to it the second meaning rather than create two different pages. Some navel gazing reuired... :-) Sergei Yakovenko 14:00, 6 May 2012 (CEST)
Well, we cannot delete a page, but we can make it empty, or replace it with "This page is to be deleted", or (better) replace it with a redirect page; the latter form of extermination is widely used on Wikipedia. --Boris Tsirelson 17:23, 6 May 2012 (CEST)
How to Cite This Entry:
Yakovenko. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Yakovenko&oldid=26127