Skip Navigation
  • UC Riverside
  • University Advancement
  • Strategic Communications

Mathematical Physics & Dynamical Systems: "Boundary amenability of groups via ultrapowers”

Dr. Isaac Goldbring, UC Irvine

Thursday, June 1, 2017
  3:40–5 p.m.

Location: Surge Building 268
  Parking Information

Category: Seminar


A group is said to be boundary amenable if it acts amenably on a compact space. This is a generalization of the notion of amenable group, which is the case that a group acts amenably on a one-point space. The prototypical example of a group that is boundary amenable but not amenable is the non-abelian free group.

In this talk, we explain how a novel construction of the Stone-Cech compactification of a space using C*-algebra ultraproducts can be used to give a slick proof of the known fact that groups that act properly and isometrically on trees are boundary amenable. We will end with a discussion of how this construction might be useful to settle the boundary amenability of Thompson's group.


Additional Information: Math Seminars

Open to: General Public
Admission: Free
Sponsor: Mathematics

Contact Information: