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arXiv · 2304.14049

Localized orthogonal decomposition for a multiscale parabolic stochastic partial differential equation

Annika Lang·Per Ljung·Axel Målqvist
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Abstract

A multiscale method is proposed for a parabolic stochastic partial differential equation with additive noise and highly oscillatory diffusion. The framework is based on the localized orthogonal decomposition (LOD) method and computes a coarse-scale representation of the elliptic operator, enriched by fine-scale information on the diffusion. Optimal order strong convergence is derived. The LOD technique is combined with a (multilevel) Monte-Carlo estimator and the weak error is analyzed. Numerical examples that confirm the theoretical findings are provided, and the computational efficiency of the method is highlighted.

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Annika Lang, Per Ljung, Axel Målqvist. 2023-04-27. Localized orthogonal decomposition for a multiscale parabolic stochastic partial differential equation. https://arxiv.org/abs/2304.14049

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