Logic Seminar

Abert and Elek have defined a topology on the space of weak
equivalence classes of measure-preserving actions of a countable group.
Tucker-Drob has extended this to the space of stable weak equivalence
classes. Both of these spaces carry a well-defined notion of convex
combination which is compatible with the topology. We will discuss
topological and geometric properties of this convex structure and present
recent results of Tucker-Drob, Bowen and the speaker.