Combinatorics Seminar 2017

Speaker: Tullio Ceccherini-Silberstein, Universita' del Sannio

Date: Tue, Sep 12, 2017

Time: 14:00 - 16:30

Venue: Large Meeting Room

Title: Amenablity and paradoxical decompositions


We discuss several aspects of amenability and non-amenability for groups, graphs, and metric spaces. The central result is Tarski alternative theorem (amenability is equivalent to absence of paradoxical decompositions). Bipartite graphs and the harem version of the Rado-Hall marriage theorem (a central result for the proof of the alternative theorem) will also be discussed.