Topology & Geometric Group Theory Seminar

Spring 2009

1:30 – 2:30, Malott 207

Tuesday, January 27

While it is not known whether Thompson's group F is amenable, I will establish a lower bound on the size of trees occurring in Følner sets. In particular, I will demonstrate the following: There is a constant C > 1 such that if A is a C⁻⁴ⁿ-Følner set in F, then A contains an element whose tree diagram has at least H(n) elements, where H(0) = 0 and H(n+1) = 2^H(n).