Dear all, here is a challenge that for me as a non-expert is very tough to solve: I have some sets of points distributed on the surface of a unit sphere. Each set was...

Can anyone point me to a reference (in English) for defining the equivariant derived category for a discrete Abelian group. In particular, I think there ought to be an...

As everyone around here must know, a lot of my professional service is devoted to the math arXiv. But here I would like to make my annual plug for another service,...

Does anyone know what the currently best known solutions are for the snake-in-the=box problem (induced paths in the n-cube) for n=8? The best solution I've seen for n=8 is...

Dear all, I would like to make a very simple and basic model of a vortex in a fluid. The model can be exactly thought as the system of water spinning in the bath-tub. I...

Journal of Algebra and Its Applications Vol. 3, No. 3 (September 2004) View contents and abstracts at http://www.worldscinet.com/jaa.html Contents: Torsion-Freeness For...

Here are this week's titles in the mathematics arXiv, available at: http://front.math.ucdavis.edu/ Instructions for contributing articles are available at: ...

I have written a paper on the equichordal point problem. Although Rychlik has claimed that he resolved the problem in the negative, I might have found a method that could...

hi all, I am working hard on a model and I need to know whether the following is true or false: PROP: - consider an undirected unweighted graph g; if g is "stable"...

Hello, Let us say that a group G satisfies the Inner HNN embedding property if, for every countable subgroup H and every embedding i:H-W of H into a countable group, there...

The PDE is u_t + u_x * u_xt = 0. Here u is the unknown function of two vars u = u(x,t). The partial wrt t is u_t, similarly wrt x is u_x, and the mixed partial is denoted ...

Dear Moderator, I want to propose here a personal solving method. h(x,y),g(x,y) RxR-R functions;f,m,n R-R continuous functions. f^ known means we've got a closed form to...

Hello: As part of my Master's Thesis; I need to integrate two elliptic integrals whose integrand is of the form: I =integral(F(x)*G(x),x=0..infinity); with...

Hi, In order to test a (precise and very fast) library of transcendental functions, a powerful graphical interface for instant analysis has been developed - it is...

Here are this week's titles in the mathematics arXiv, available at: http://front.math.ucdavis.edu/ Instructions for contributing articles are available at: ...

Hi, I read a bit about this person; apparently he has mathematically modelled some elements of human psychology. It sounds fascinating as supposedly his formulas can...

Hi, Is there a meaningful way to define the category of commutative diagrams of a category. My goal would be to replace a statements of the form "forall blah blah the...

What motivates you to ask these questions? Thanks Todd for your very helpful answers to my questions. Here my motivation was just to have a better understanding of comma...

hi, I realise that what I'm asking is not a research level question. But I hope I can get answer from someone in this group. If we take a random binary sequence of...

The following paper has been published: Algebraic and Geometric Topology Volume 4 (2004), paper no. 38, pages...