Groups and Dynamics Seminar

Date: September 27, 2017

Time: 3:00PM - 4:00PM

Location: BLOC 220

Speaker: Robin Tucker-Drob, Texas A&M

Title: Invariant means and inner amenable groups II

Abstract: I will present the proof of the characterization of inner amenable linear groups which I mentioned in my last talk: A linear group G is inner amenable if and only if there is an infinite amenable normal subgroup N of G such that G/C_G(N) is amenable. The main ingredient is a "forgotten lemma" of S.G. Dani from 1985 concerning amenable actions which satisfy a certain chain condition. Time permitted, I will also discuss a closely related characterization of linear groups which are J.S.-stable.