Modul: MAT075 Zurich Graduate Colloquium

## What are.. the ends of a group?

Talk by Davide Spriano

**Date:** 25.02.20 **Time:** 16.30 - 17.30 **Room:**

The key idea of geometric group theory is to treat groups as metric spaces and to find correspondences between algebraic and geometric properties. In this introductory talk, we will survey some basic construction and define the number of ends of a group. This is a simple, intuitive geometric invariant which has, nevertheless, deep consequences. A consequence of particular interest on which we will focus is Stalling's theorem about splittings over finite groups.