Mini-Workshop: MASAs and Automorphisms of C*-Algebras

Abstract

The main aim of this workshop was to study maximal abelian *-subalgebras of C*-algebras from various points of view. A chief motivation is the UCT problem, which asks whether all separable nuclear C*-algebras satisfy the universal coefficient theorem of Rosenberg and Schochet. The connection, in terms of existence of invariant Cartan MASAs for certain *-automorphisms of the Cuntz algebra, has been brought up only very recently; it opens up a line of new perspectives on pressing questions in the structure and classification theory of simple nuclear C*-algebras and their automorphism groups, which has made giant leaps forward in the past five years. Connections to other areas, in particular von Neumann algebras and coarse geometry, have been explored as well.