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arXiv · 1105.5391

Extreme black hole simulations: collisions of unequal mass black holes and the point particle limit

Ulrich Sperhake·Vitor Cardoso·Christian D. Ott·Erik Schnetter·Helvi Witek
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Abstract

Numerical relativity has seen incredible progress in the last years, and is being applied with success to a variety of physical phenomena, from gravitational-wave research and relativistic astrophysics to cosmology and high-energy physics. Here we probe the limits of current numerical setups, by studying collisions of unequal mass, non-rotating black holes of mass-ratios up to 1:100 and making contact with a classical calculation in General Relativity: the infall of a point-like particle into a massive black hole. Our results agree well with the predictions coming from linearized calculations of the infall of point-like particles into non-rotating black holes. In particular, in the limit that one hole is much smaller than the other, and the infall starts from an infinite initial separation, we recover the point-particle limit. Thus, numerical relativity is able to bridge the gap between fully non-linear dynamics and linearized approximations, which may have important applications. Finally, we also comment on the "spurious" radiation content in the initial data and the linearized predictions.

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Ulrich Sperhake, Vitor Cardoso, Christian D. Ott, Erik Schnetter, Helvi Witek. 2011-05-26. Extreme black hole simulations: collisions of unequal mass black holes and the point particle limit. https://doi.org/10.1103/physrevd.84.084038

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