Copenhagen
Groups and Operator Algebras Seminar

Abstract:  Given a finitely generated group G, a non-trivial element g in G, and a minimal action of G on a compact space X, with amenable stabilizers, we prove sufficient conditions in terms of various growth/decay functions for topological freeness of the action of g on X. We apply our results to the case of the (Furstenberg) boundary action of G, to conclude C*-simplicity under (semi)rapid decay conditions. In this context, we also give a description of the support of stationary states on the reduced C*-algebra of G. We further extend these techniques to conclude topological freeness for more general classes of actions under growth assumptions on the C*-algebras generated by unitary representations weakly containing the quasi-regular representations of the stabilizer subgroups.

Abstract:  TBA

Abstract:  TBA