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arXiv · 2011.07709

A high-order exponential integrator for nonlinear parabolic equations with nonsmooth initial data

Buyang Li·Shu Ma
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Abstract

A variable stepsize exponential multistep integrator, with contour integral approximation of the operator-valued exponential functions, is proposed for solving semilinear parabolic equations with nonsmooth initial data. By this approach, the exponential k-step method would have $k$th-order convergence in approximating a mild solution, possibly nonsmooth at the initial time. In consistency with the theoretical analysis, a numerical example shows that the method can achieve high-order convergence in the maximum norm for semilinear parabolic equations with discontinuous initial data.

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Buyang Li, Shu Ma. 2020-11-16. A high-order exponential integrator for nonlinear parabolic equations with nonsmooth initial data. https://arxiv.org/abs/2011.07709

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