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Almost-stationary motions and gauge conditions in General Relativity

C. Bona·J. Carot·C. Palenzuela-Luque
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Abstract

An almost-stationary gauge condition is proposed with a view to Numerical Relativity applications. The time lines are defined as the integral curves of the timelike solutions of the harmonic almost-Killing equation. This vector equation is derived by a variational principle, by minimizing the deviations from isometry. The corresponding almost-stationary gauge condition allows one to put the field equations in hyperbolic form, both in the free-evolution ADM and in the Z4 formalisms.

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C. Bona, J. Carot, C. Palenzuela-Luque. 2005-12-14. Almost-stationary motions and gauge conditions in General Relativity. https://doi.org/10.1103/physrevd.72.124010

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