Speaker: Michel Brion
Date: February 02, 2012
Affiliation: Institute Fourier, France

Abstract: Given a system of polynomial equations with integer coefficients, one may first reduce it modulo any prime $p$, and then count the solutions over the prime field F_p and larger finite fields. The talk will present some remarkable properties of the resulting counting function, first for general systems and then for those where the complex solutions form a unique orbit under the action of some algebraic group.