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Dynamical shift conditions for the Z4 and BSSN hyperbolic formalisms

C. Bona·C. Palenzuela
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Abstract

A class of dynamical shift conditions is shown to lead to a strongly hyperbolic evolution system, both in the Z4 and in the BSSN Numerical Relativity formalisms. This class generalizes the harmonic shift condition, where light speed is the only non-trivial characteristic speed, and it is contained into the multi-parameter family of minimal distortion shift conditions recently proposed by Lindblom and Scheel. The relationship with the analogous 'dynamical freezing' shift conditions used in black hole simulations discussed.

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C. Bona, C. Palenzuela. 2004-03-22. Dynamical shift conditions for the Z4 and BSSN hyperbolic formalisms. https://doi.org/10.1103/physrevd.69.104003

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