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Approximate Black Holes for Numerical Relativity

Maurice H. P. M. van Putten
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Abstract

Spherically symmetric solutions in Brans-Dicke theory of relativity with zero coupling constant, $ω=0$, are derived in the Schwarzschild line-element. The solutions are obtained from a cubic transition equation with one small parameter. The exterior space-time of one family of solutions is arbitrarily close to the exterior Schwarzschild space-time. These nontopological solitons have some similarity with soliton stars, and are proposed as candidates for {\em approximate black holes} for the use in numerical relativity, in particular for treatment of horizon boundary conditions.

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Maurice H. P. M. van Putten. 1996-07-30. Approximate Black Holes for Numerical Relativity. https://doi.org/10.1103/physrevd.54.r5931

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