Séminaire Gaston Darboux
vendredi 21 janvier 2011 à 11:15 - salle 431
Marco Mazzucchelli (ENS Lyon)
On the multiplicity of periodic orbits for Tonelli systems
In this talk I shall sketch a proof of the following result: on a closed configuration space, the Euler-Lagrange system associated to any time-periodic Tonelli Lagrangian function admits infinitely many periodic solutions. More precisely, I will show that there are infinitely many contractible periodic orbits with a priori bounded mean action and either infinitely many of them are 1-periodic or their basic period is unbounded.