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arXiv · 2007.13603

The non-isentropic Einstein-Euler system written in a symmetric hyperbolic form

Uwe Brauer·Lavi Karp
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Abstract

We cast the non--isentropic relativistic Euler system into a symmetric hyperbolic form. Such systems are very suited to treat initial value problems of hyperbolic type. We obtain this form by using the pressure $p$ and not the density $\rho$ as a variable. However, the system becomes degenerate when the pressure $p$ approaches zero, and in these cases we regularise the system by replacing the pressure with an appropriate new matter variable, the Makino variable.

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Uwe Brauer, Lavi Karp. 2020-07-27. The non-isentropic Einstein-Euler system written in a symmetric hyperbolic form. https://doi.org/10.1007/978-3-030-61346-4

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