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Hyperbolicity of the BSSN system of Einstein evolution equations

Olivier Sarbach·Gioel Calabrese·Jorge Pullin·Manuel Tiglio
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Abstract

We discuss an equivalence between the Baumgarte-Shapiro-Shibata-Nakamura (BSSN) formulation of the Einstein evolution equations, a subfamiliy of the Kidder--Scheel--Teukolsky formulation, and other strongly or symmetric hyperbolic first order systems with fixed shift and densitized lapse. This allows us to show under which conditions the BSSN system is, in a sense to be discussed, hyperbolic. This desirable property may account in part for the empirically observed better behavior of the BSSN formulation in numerical evolutions involving black holes.

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Olivier Sarbach, Gioel Calabrese, Jorge Pullin, Manuel Tiglio. 2002-05-15. Hyperbolicity of the BSSN system of Einstein evolution equations. https://doi.org/10.1103/physrevd.66.064002

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