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Cauchy-perturbative matching and outer boundary conditions I: Methods and tests

M. E. Rupright·A. M. Abrahams·L. Rezzolla
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Abstract

We present a new method of extracting gravitational radiation from three-dimensional numerical relativity codes and providing outer boundary conditions. Our approach matches the solution of a Cauchy evolution of Einstein's equations to a set of one-dimensional linear wave equations on a curved background. We illustrate the mathematical properties of our approach and discuss a numerical module we have constructed for this purpose. This module implements the perturbative matching approach in connection with a generic three-dimensional numerical relativity simulation. Tests of its accuracy and second-order convergence are presented with analytic linear wave data.

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M. E. Rupright, A. M. Abrahams, L. Rezzolla. 1998-02-03. Cauchy-perturbative matching and outer boundary conditions I: Methods and tests. https://doi.org/10.1103/physrevd.58.044005

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