A convergent adaptive stochastic Galerkin finite element method with quasi-optimal spatial meshes

We analyze a-posteriori error estimation and adaptive refinement algorithms for stochastic Galerkin Finite Element methods for countably-parametric, elliptic boundary value problems. A residual error estimator which separates the effects of gpc-Galerkin discretization in parameter space and of the Finite Element discretization in physical space in energy norm is established. It is proved that the adaptive algorithm converges, and to this end we establish a contraction property satisfied by its iterates. It is shown that the sequences of triangulations which are produced by the algorithm in the FE dis-cretization of the active gpc coefficients are asymptotically optimal. Numerical experiments illustrate the theoretical results.