If M is a closed Riemannian manifold of negative curvature then each free homotopy class of curves of M contains a unique closed geodesic. The marked length spectrum of M is the function which assigns to each free homotopy class of closed curves the length of its geodesic representative. In the case where M is a surface, Otal proved that this function determines M completely up to isometry. In this talk, I will explain the main ideas behind Otal's proof. No prior knowledge of differential geometry or dynamics will be assumed.

Speaker(s): Karen Butt (UM)