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arXiv · 1003.0873

Understanding the "anti-kick" in the merger of binary black holes

Luciano Rezzolla·Rodrigo P. Macedo·José Luis Jaramillo
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Abstract

The generation of a large recoil velocity from the inspiral and merger of binary black holes represents one of the most exciting results of numerical-relativity calculations. While many aspects of this process have been investigated and explained, the "antikick", namely the sudden deceleration after the merger, has not yet found a simple explanation. We show that the antikick can be understood in terms of the radiation from a deformed black hole where the anisotropic curvature distribution on the horizon correlates with the direction and intensity of the recoil. Our analysis is focussed on Robinson-Trautman spacetimes and allows us to measure both the energies and momenta radiated in a gauge-invariant manner. At the same time, this simpler setup provides the qualitative and quantitative features of merging black holes, opening the way to a deeper understanding of the nonlinear dynamics of black-hole spacetimes.

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Luciano Rezzolla, Rodrigo P. Macedo, José Luis Jaramillo. 2010-06-28. Understanding the "anti-kick" in the merger of binary black holes. https://doi.org/10.1103/physrevlett.104.221101

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