Josh Frisch: "Characteristic measures of symbolic dynamical systems"

mardi 26 nov. 2019, 10:15 → 11:45 Europe/Paris

 

A measure on a topological dynamical system, i.e, a group acting by homeomorphisms on a compact Hausdorff space is said to be invariant if it does not change under the group action. For some topological systems there are many invariant measures, none of which seem especially canonical. Given a topological dynamical system, the automorphism group is the group of homeomorphisms which commute with the group action. We call a measure invariant to the automorphism group a characteristic measures. In this talk I will give some situations when characteristic measures do exist, examples when they don't, and a number of situations where we don't know. This is joint work with Omer Tamuz.