Special Session 11: Stochastic Partial Differential Equations

On the approximation of finite-time Lyapunov exponents for the stochastic Burgers equation
Dirk Bl\"omker
Universit\"at Augsburg
Germany
Co-Author(s):    Alexandra Blessing
Abstract:
We analyze stochastic partial differential equations (SPDEs) with quadratic nonlinearities close to a change of stability. To this aim we compute finite-time Lyapunov exponents (FTLEs), observing a change of sign based on the interplay between the distance towards the bifurcation and the noise intensity. We reduce the infinite dimensional equation to an SDE on the dominant modes and carry over results for FTLE from the finite to the infinite dimensional setting. A technical challenge is to provide a suitable control of the nonlinear terms coupling the dominant and stable modes of the SPDE and of the corresponding linearization. In order to illustrate our results we apply them to the stochastic Burgers equation.