Activities This Week
Operator Algebras and Operator Theory
Simplicity of reduced crossed products
Mar 8, 10:00—11:00, 2023, Minus 101
Speaker
Shirly Geffen (Muenster)
Abstract
Results from a few years ago of Kennedy and Schafhauser attempt to characterize simplicity of noncommutative reduced crossed products, under an assumption which they call vanishing obstruction. However, this is a strong condition that often fails, even in cases of finite groups acting on finite dimensional C-algebras. In this work, we give complete, two-way, C-dynamical characterization, of when the crossed product is simple, in the setting of FC-hypercentral groups. This is a large class of amenable groups that, in the finitely-generated setting, is known to coincide with the set of groups with polynomial growth.
This is joint work in its early stages with Dan Ursu.