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arXiv · 2006.05309

Brown-York energy in stationary spacetimes

Hongsheng Zhang
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Abstract

One usually defines the Brown-York energy for a 2-surface embedded in a spacelike 3-slice as an integration of the mean curvature of the 2-surface isometrically embedded into the 3-slice, with a proper reference 3-space. We demonstrate that this naive definition is ill for stationary spacetimes. As an example, we investigate the Kerr-Newman spacetime in detail. We show that the naive definition of the Brown-York energy is not a component of the Brown-York boundary stress tensor, and thus deviates from the original idea of Brown and York. Furthermore, we present the exact form of the Brown-York energy for the Kerr-Newman spacetime with the proper reference.

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Hongsheng Zhang. 2020-06-07. Brown-York energy in stationary spacetimes. https://doi.org/10.1142/s0217732320501825

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