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arXiv · 1807.06260

Penrose quasi-local energy and Kerr-Schild metrics

Mahdi Godazgar·Andre Kaderli
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Abstract

Specialising to the case of Kerr-Schild spacetimes, which include the Kerr black hole and gravitational wave solutions, we propose a modification of the Penrose quasi-local energy. The modification relies on the existence of a natural Minkowski background for Kerr-Schild spacetimes. We find that the modified surface integral reduces to a volume integral of the Einstein tensor, which has been proposed previously as an appropriate definition for quasi-local energy for Kerr-Schild backgrounds. Furthermore, in the special case that the Kerr-Schild null vector is normal to the surface of interest, we construct a 1-1 map between the 2-surface twistors in the Kerr-Schild background and Minkowski twistors projected onto the surface.

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Mahdi Godazgar, Andre Kaderli. 2018-09-26. Penrose quasi-local energy and Kerr-Schild metrics. https://doi.org/10.1088/1361-6382%2Faae444

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