Actions of compact groups on C*-algebras with finite Rokhlin dimension
Abstract: A classical result of Jones, based on previous work by Connes, states that for actions of finite groups on the hyperfinite II1 factor, pointwise outerness is equivalent to having the Rokhlin property. In this talk I will discuss analogs of this result in the setting of C*-algebras. I will also discuss several properties of actions of compact groups on C*-algebras with finite Rokhlin dimension, particularly in relation to crossed products. I will show how taking crossed products by such actions preserves a number of relevant classes of C*-algebras, including: D-absorbing C*-algebras (where D is strongly self-absorbing), finite stable rank, C*-algebras with finite nuclear dimension or decomposition rank, C*-algebras that are nuclear and satisfy the UCT, among others. I will introduce a representability dimension for actions of discrete groups on C*-algebras and show that in the abelian setting the dual action of an action of a compact group with finite Rokhlin dimension has finite representability dimension.
This a joint work with Eusebio Gardella and Ilan Hirshberg.