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arXiv · 1503.00073

Full discretisation of semi-linear stochastic wave equations driven by multiplicative noise

Rikard Anton·David Cohen·Stig Larsson·Xiaojie Wang
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Abstract

A fully discrete approximation of the semi-linear stochastic wave equation driven by multiplicative noise is presented. A standard linear finite element approximation is used in space and a stochastic trigonometric method for the temporal approximation. This explicit time integrator allows for mean-square error bounds independent of the space discretisation and thus do not suffer from a step size restriction as in the often used St\"ormer-Verlet-leap-frog scheme. Furthermore, it satisfies an almost trace formula (i.e., a linear drift of the expected value of the energy of the problem). Numerical experiments are presented and confirm the theoretical results.

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Rikard Anton, David Cohen, Stig Larsson, Xiaojie Wang. 2015-02-28. Full discretisation of semi-linear stochastic wave equations driven by multiplicative noise. https://arxiv.org/abs/1503.00073

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