"Ghost Numbers of Group Algebras"
By
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
Time: 13.40-14.30
Place: Mathematics Seminar Room,
SA-141
All are most cordially invited.
Tea and cookies will be served after the talk.