Weak second order multi-revolution composition methods
for highly oscillatory stochastic differential equations
with additive or multiplicative noise
Gilles Vilmart
Abstract.
We introduce a class of numerical methods for highly oscillatory systems of stochastic
differential equations with general noncommutative noise. We prove global weak
error bounds of order two uniformly with respect to the stiffness of the oscillations,
which permits to use large time steps. The approach is based on the micro-macro
framework of multi-revolution composition methods recently introduced for deterministic
problems and inherits its geometric features, in particular to design integrators preserving
exactly quadratic first integral. Numerical experiments, including the stochastic
nonlinear Schršodinger equation with space-time multiplicative noise, illustrate the performance
and versatility of the approach.
Key Words. highly-oscillatory stochastic differential equation, composition method,
quadratic first integral conservation, multiplicative noise, time-dependent stochastic
Schršodinger equation.