Marc Stephan

The motivation for this talk comes from a basic open problem in
equivariant topology: determining lower bounds for the sum of mod-p Betti
numbers of finite CW-complexes with a free (Z/p)^n-action. For p=2,
Carlsson connected chain complexes with a free (Z/p)^n-action to DG modules
over a polynomial ring in order to establish lower bounds using commutative
algebra and algebraic geometry.

In this talk, I will explain this connection and the problem in algebraic
geometry arising from it. Thereafter, I will describe an extension to all
primes using p-DG modules as developed in the Hopfological algebra
framework of Khovanov and Qi. This is joint work with Jeremiah Heller.