Weak Gravity Conjecture and Extremal Black Holes

William Cottrell; Gary Shiu; Pablo Soler

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arXiv · 1611.06270

Weak Gravity Conjecture and Extremal Black Holes

William Cottrell·Gary Shiu·Pablo Soler

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Abstract

Motivated by the desire to improve our understanding of the Weak Gravity Conjecture, we compute the one-loop correction of charged particles to the geometry and entropy of extremal black holes in 4d. We find that fermion loops provide evidence for the necessity of the `magnetic' WGC cutoff. Moreover, for a certain regime of black holes, we find entropy corrections with unusual area scaling. The corrections are reduced when supersymmetry is present, and disappear in ${\cal N}=4$ supergravity. We further provide some speculative arguments that in a theory with only sub-extremal particles, classical Reissner-Nordstrom black holes actually possess an infinite microcanonical entropy, though only a finite amount is visible to an external observer.

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William Cottrell, Gary Shiu, Pablo Soler. 2016-11-18. Weak Gravity Conjecture and Extremal Black Holes. https://arxiv.org/abs/1611.06270

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