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arXiv · 2005.04659

Quasi-local energy and Oppenheimer-Snyder collapse

Xiaokai He·Naqing Xie
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Abstract

We consider a scenario of the gravitational collapse of the Oppenheimer-Snyder dust cloud with spatially constant matter density. Given a closed two-surface within the star, three versions of the quasi-local energy are investigated. We show that, during the collapse, (i) the Geroch energy of the surface is nonpositive and increases to zero; (ii) the Hawking energy of the surface is monotonically increasing and approaches to the Hayward energy of the initial surface; and (iii) the Hayward energy of the surface is conserved and remains positive. These results have no restrictions on the topology and the symmetry of the surface.

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Xiaokai He, Naqing Xie. 2020-05-10. Quasi-local energy and Oppenheimer-Snyder collapse. https://doi.org/10.1088/1361-6382%2Faba31c

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