Groups acting at infinity

I will present some recent results on rigidity of group actions and flows that come from looking at induced actions on “boundaries at infinity”. This idea has a long history, going back to Selberg and Mostow. In some of my recent joint work, I use this approach in geometric group theory and dynamics, studying boundary rigidity for actions of hyperbolic groups on their Gromov boundary, and showing Anosov flows on 3-manifolds are determined by their periodic orbits. This talk will survey some of the history, philosophy and techniques related to proving rigidity results by looking out to infinity.

Biography

Originally from Toronto, Kathryn Mann obtained her PhD from the University of Chicago in 2014. She held postdoctoral positions at UC Berkeley and MSRI, and was an assistant professor at Brown before moving to Cornell in 2019. She has received several honors for her work, including the 2016 Mary Ellen Rudin Award, the 2019 Birman research fellowship in topology, and the Kamil Duszenko award in geometric group theory.