# Boundary C*-algebras of acylindrical groups

### Guyan Robertson (Newcastle)

Tuesday 24th February, 2009 16:00-17:00 214

#### Abstract

Let $\Delta$ be a locally finite tree with infinite boundary. Let $\Gamma$ be an acylindrical group of automorphisms of $\Delta$, with finitely many vertex orbits. Then the boundary algebra $C(\partial\Delta)\rtimes \Gamma$ depends only on $\Gamma$ and is a simple Cuntz-Krieger algebra whose K-theory can be determined explicitly.