Appears in collection : Anosov Dynamics / La dynamique des sytèmes d'Anosov
We will introduce some tools from analysis (in particular microlocal analysis) in order to understand the Fredholm theory of Anosov flows. We will then explain how these tools can be used to study a rigidity problem consisting in determining a Riemannian metric from the lengths of its marked closed geodesics, and we will describe a variational approach to study this problem locally near a fixed negatively curved Riemannian metric on a closed manifold.