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Constraint-preserving Sommerfeld conditions for the harmonic Einstein equations

M. C. Babiuc·H-O. Kreiss·Jeffrey Winicour
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Abstract

The principle part of Einstein equations in the harmonic gauge consists of a constrained system of 10 curved space wave equations for the components of the space-time metric. A new formulation of constraint-preserving boundary conditions of the Sommerfeld type for such systems has recently been proposed. We implement these boundary conditions in a nonlinear 3D evolution code and test their accuracy.

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M. C. Babiuc, H-O. Kreiss, Jeffrey Winicour. 2006-12-08. Constraint-preserving Sommerfeld conditions for the harmonic Einstein equations. https://doi.org/10.1103/physrevd.75.044002

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