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arXiv · 2107.12400

The Kijowski--Liu--Yau quasi-local mass of the Kerr black hole horizon

Maciej Dunajski·Paul Tod
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Abstract

We use the isometric embedding of the spatial horizon of fast rotating Kerr black hole in a hyperbolic space to compute the quasi-local mass of the horizon for any value of the spin parameter $j=J/m^2$. The mass is monotonically decreasing from twice the ADM mass at $j=0$ to $1.76569m$ at $j=\sqrt{3}/2$. It then monotonicaly increases to a maximum around $j=0.99907$, and finally decreases to $2.01966m$ for $j=1$ which corresponds to the extreme Kerr black hole.

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Maciej Dunajski, Paul Tod. 2021-07-26. The Kijowski--Liu--Yau quasi-local mass of the Kerr black hole horizon. https://doi.org/10.1088/1361-6382%2Fac2cb6

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