"Ghost Numbers of Group Algebras"
Abstract: A ghost in the stable module category of a finite group G is a map between modular representations of G which induces a trivial map on Tate cohomology. The Freyd's generating hypothesis (GH) for the stable module category of G is the statement that every ghost between finitely generated modular representations of G factors through a projective module. In this talk, we discuss p-groups for which GH fails and then we introduce the ghost number of a group algebra which measures the degree of the failure of GH.
Date: Monday, March 4, 2013
Place: Mathematics Seminar Room, SA-141
All are most cordially invited.
Tea and cookies will be served after the talk.