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arXiv · 1711.08221

Towards an exascale code for GRMHD on dynamical spacetimes

Sven Köppel
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Abstract

We present the first results on the construction of an exascale hyperbolic PDE engine (ExaHyPE), a code for the next generation of supercomputers with the objective to evolve dynamical spacetimes of black holes, neutron stars and binaries. We solve a novel first order formulation of Einstein field equations in the conformal and constraint damping Z4 formulation (CCZ4) coupled to ideal general relativistic magnetohydrodynamics (GRMHD), using divergence-cleaning. We adopt a novel communication-avoiding one-step ADER-DG scheme with an a-posteriori subcell finite volume limiter on adaptive spacetrees. Despite being only at its first stages, the code passes a number of tests in special and general relativity.

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Sven Köppel. 2017-11-22. Towards an exascale code for GRMHD on dynamical spacetimes. https://doi.org/10.1088/1742-6596%2F1031%2F1%2F012017

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