Résume | I will present some recent results on rigidity of group actions and flows that come from looking at induced actions on "boundaries at infinity". To give some examples: in joint work with Bowden, Manning and Weisman, we show that the action of a hyperbolic group on its Gromov boundary is stable in the sense of topological dynamics. In work with Barthelme and Frankel, we use boundary actions to show that Anosov flows on 3-manifolds are determined by their periodic orbits. This talk will survey some of the common philosophy and techniques. |