Résumé : We consider the 2D Euler equation in a bounded domain driven
by a multiplicative noise. We prove the existence of martingale
solutions in the space of finite energy and finite enstrophy. The
method used is an approximation of the Euler equation by a modified
Navier-Stokes one combined with a martingale representation theorem.
A uniqueness result is proved when the noise is additive.

Cet exposé se tiendra en salle C20-13, 20ème étage, Université
Paris 1, Centre Pierre Mendès-France, 90 rue de Tolbiac, 75013 Paris
(métro : Olympiades).