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arXiv · 1903.09915

Comparison of numerical methods for the nonlinear Klein-Gordon equation in the nonrelativistic limit regime

Weizhu Bao
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Abstract

Different efficient and accurate numerical methods have recently been proposed and analyzed for the nonlinear Klein-Gordon equation (NKGE) with a dimensionless parameter $\varepsilon\in (0,1]$, which is inversely proportional to the speed of light. In the nonrelativestic limit regime, i.e. $0<\varepsilon\ll1$, the solution of the NKGE propagates waves with wavelength at $O(1)$ and $O(\varepsilon^2)$ in space and time, respectively, which brings significantly numerical burdens in designing numerical methods. We compare systematically spatial/temporal efficiency and accuracy as well as $\varepsilon$-resolution (or $\varepsilon$-scalability) of different numerical methods including finite difference time domain methods, time-splitting method, exponential wave integrator, limit integrator, multiscale time integrator, two-scale formulation method and iterative exponential integrator. Finally, we adopt the multiscale time integrator to study the convergence rates from the NKGE to its limiting models when $\varepsilon\to0^+$.

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Weizhu Bao. 2019-03-24. Comparison of numerical methods for the nonlinear Klein-Gordon equation in the nonrelativistic limit regime. https://doi.org/10.1016/j.jcp.2019.108886

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