13:00
Length functions of right-angled Artin groups
Abstract
Morgan and Culler proved in the 1980’s that a minimal action of a free group on a tree is
completely determined by its length function. This theorem has been of fundamental importance in the
study of automorphisms of free groups. In particular, it gives rise to a compactification of Culler-Vogtmann's
Outer Space. We prove a 2-dimensional analogue of this theorem for right-angled Artin groups acting on
CAT(0) rectangle complexes. (Joint work with M. Margolis)