Algèbre, géométrie, topologie

Surfaces of section, Anosov Reeb Flows, and the C2-stability conjecture for geodesic flows

by Marco Mazzuchelli (ENS Lyon)




In this talk, based on joint work with Gonzalo Contreras, I will briefly sketch the proof of the existence of global surfaces of section for the Reeb flows of closed 3-manifolds satisfying a condition à la Kupka-Smale : non-degeneracy of the closed Reeb orbits, and transversality of the stable and unstable manifolds of the hyperbolic closed Reeb orbits. I will then present an application of this theorem to hyperbolic Reeb dynamics : a Reeb flow on a closed 3-manifold is Anosov if and only if the closure of the subspace of closed Reeb orbits is hyperbolic and the Kupka-Smale transversality condition holds. This re- sult implies the validity of the C2 stability conjecture for Riemannian geodesic flows of closed surfaces : any such geodesic flow that is C2 structurally stable within the class of Riemannian geodesic flows must be Anosov.