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arXiv · 2404.01531

General relativistic force-free electrodynamics with a discontinuous Galerkin-finite difference hybrid method

Yoonsoo Kim·Elias R. Most·William Throwe·Saul A. Teukolsky·Nils Deppe
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Abstract

Relativistic plasmas around compact objects can sometimes be approximated as being force-free. In this limit, the plasma inertia is negligible and the overall dynamics is governed by global electric currents. We present a novel numerical approach for simulating such force-free plasmas, which allows for high accuracy in smooth regions as well as capturing dissipation in current sheets. Using a high-order accurate discontinuous Galerkin method augmented with a conservative finite-difference method, we demonstrate efficient global simulations of black hole and neutron star magnetospheres. In addition to a series of challenging test problems, we show that our approach can-depending on the physical properties of the system and the numerical implementation-be up to 10x more efficient than conventional simulations, with a speedup of 2-3x for most problems we consider in practice.

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Yoonsoo Kim, Elias R. Most, William Throwe, Saul A. Teukolsky, Nils Deppe. 2024-04-01. General relativistic force-free electrodynamics with a discontinuous Galerkin-finite difference hybrid method. https://doi.org/10.1103/physrevd.109.123019

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