Analysis Seminar

Matthew Kennedy, Department of Pure Math, University of Waterloo 

“An intrinsic algebraic characterization of C*-simplicity for discrete groups”

A discrete group is said to be C*-simple if its reduced C*-algebra is simple. It is not difficult to see that any C*-simple group necessarily has no non-trivial normal amenable subgroups, and it was an open question for some time to determine whether the converse holds. Recent ex- amples constructed by Le Boudec in the summer of 2015 show that the answer to this question is negative, but raises the question of whether there is an intrinsic algebraic characterization of C*-simplicity. In this talk, after a brief review of some background material, I will discuss recent work providing such a characterization.

MC 5417