Quasi-invariant gaussian measures for the nonlinear wave equation

Nikolay Tzvetkov
Univ. de Cergy-Pontoise

Abstract: We will show that a natural class of gaussian measures living on Sobolev spaces of varying regularity are quasi-invariant under the flow of the two dimensional cubic defocusing wave equation. For that purpose, we introduce renormalised energies and we establish the associated energy estimates.
This is a joint work with Tadahiro Oh (Edinburgh University).