In these lectures, we are interested in the chaotic behaviour of the geodesic flow of hyperbolic surfaces. To understand it from an ergodic point of view, we will build a family of invariant measures called "Gibbs measures", and use their product structure to deduce chaotic properties of the flow. We will also present some situations where this family of measures leads to nice geometric results.
37A10 ; 37A35 ; 37A40 ; 37B40 ; 37D35 ; 37D40