## Section: New Results

### Stochastic Cahn-Hilliard equation with double singular nonlinearities and two reflections

Participant : Arnaud Debussche.

In [25] we consider a stochastic partial differential equation with two logarithmic nonlinearities, two reflections at 1 and -1, and a constraint of conservation of the space average. The equation, driven by the derivative in space of a space-time white noise, contains a bi-Laplacian in the drift. The lack of a maximum principle for the bi-Laplacian generates difficulties for the classical penalization method, which uses a crucial monotonicity property. Being inspired by the works of Debussche, Goudenège, and Zambotti, we obtain existence and uniqueness of a solution for initial conditions in the interval $\left(-1,1\right)$. Finally, we prove that the unique invariant measure is ergodic, and we give a result of exponential mixing.