Eric M. Friedlander
Title: Support Varieties
Abstract:
We give a survey of algebro-geometric techniques developed to
investigate modular representation theory
of "groups" associated
to an algebraic group. Forty years ago, D. Quillen initiated this
with his determination of the
homeomorphism type of the spectrum
of the cohomology ring of a finite group. Subsequently, suport
varieties were
introduced associated to group representations,
initially defined as subvarieties of this spectrum of cohomology.
Over the years, more refined invariants of representations have been
formulated and more general "groups" than
finite groups have been
considered. Work in progress suggests that at least some aspects of
these techniques apply
as well to representations of algebraic groups.