Operator algebra seminar – University of Copenhagen

Operator algebra seminar

Speaker: Alejandra Garrido (HHU Düsseldorf)

Title: On quotients and representations of some just infinite groups

Abstract: Just infinite groups are infinite groups all of whose proper quotients are finite. Since every infinite finitely generated group has a just infinite quotient, this is a natural class to study when interested in properties of groups that pass to quotients (e.g. amenability, property (T)). One of the classes into which just infinite groups splits is that of just infinite branch groups, which contains many examples of groups with hitherto unseen properties. I will discuss some results about quotients and profinite completions of branch groups and talk about the study of their representations, especially in relation to property (T) and C*-algebras.