PSU Mark
Eberly College of Science Mathematics Department

Meeting Details

For more information about this meeting, contact Mari Royer, Yakov Pesin, Anatole Katok, Svetlana Katok, Dmitri Burago.

Title:On a simpler proof of the invariant torus theorem in KAM theory
Seminar:Center for Dynamics and Geometry Seminars
Speaker:Jacques Fejoz, Paris 6 and Observatoire de Paris
Abstract:
Under some non degeneracy condition of the Hamiltonian, this theorem asserts that a diophantine, quasiperiodic, invariant Lagrangian torus persists under small perturbations of the Hamiltonian. There are many proofs of this theorem. All of them are rendered difficult by the presence of small denominators, which prevents from using the usual inverse function theorem in Banach spaces. I will sketch a proof in the category of real analytic Hamiltonians, which simplifies and combines Zehnder's and Herman's approaches. In particular, very explicit bounds for the perturbation are obtained.

Room Reservation Information

Room Number:MB106
Date:02 / 25 / 2009
Time:03:30pm - 05:30pm