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arXiv · gr-qc/0003031

Making use of geometrical invariants in black hole collisions

J. Baker·M. Campanelli
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Abstract

We consider curvature invariants in the context of black hole collision simulations. In particular, we propose a simple and elegant combination of the Weyl invariants I and J, the {\sl speciality index} ${\cal S}$. In the context of black hole perturbations $\cal S$ provides a measure of the size of the distortions from an ideal Kerr black hole spacetime. Explicit calculations in well-known examples of axisymmetric black hole collisions demonstrate that this quantity may serve as a useful tool for predicting in which cases perturbative dynamics provide an accurate estimate of the radiation waveform and energy. This makes ${\cal S}$ particularly suited to studying the transition from nonlinear to linear dynamics and for invariant interpretation of numerical results.

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J. Baker, M. Campanelli. 2000-03-08. Making use of geometrical invariants in black hole collisions. https://doi.org/10.1103/physrevd.62.127501

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