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arXiv · 2108.05686

Extremal Bifurcations of Rotating AdS$_4$ Black Holes

Brett McInnes
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Abstract

The Weak Gravity Conjecture arises from the assertion that all extremal black holes, even those which are "classical" in the sense of being very massive, must decay by quantum-mechanical emission of particles or smaller black holes. This is interesting, because some observed astrophysical black holes are on the brink of being extremal -- $\,$ though this is due to rapid rotation rather than a large electric or magnetic charge. The possibility that rotating near-extremal black holes might, in addition to radiating spinning particles, also bifurcate by emitting smaller black holes, has attracted much attention of late. There is, however, a basic question to be answered here: can such a bifurcation be compatible with the second law of thermodynamics? This is by no means clear. Here we show that, if there is indeed such a mechanism for bifurcations of AdS$_4$-Kerr-Newman black holes, then this process can in fact satisfy the second law.

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Brett McInnes. 2021-08-12. Extremal Bifurcations of Rotating AdS$_4$ Black Holes. https://doi.org/10.1007/jhep12(2021)155

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