Logic Seminar

Percolation and invariant random subgroups

Yair Hartman, Mathematics, Northwestern University,

I will illustrate an application of simple ideas from percolation to the study of invariant random subgroups (IRS). We use percolation to construct a continuum of IRSs on groups, for which we show that Furstenberg entropy varies continuously. For example, we obtain a short proof to the solution of the Furstenberg realization problem for the lamplighter group.