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arXiv · 2010.11590

A comment on no-force conditions for black holes and branes

Thomas Van Riet
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Abstract

In the context of the Weak Gravity Conjecture the notion of quasi-extremality for black holes and branes was recently defined as the property of having either vanishing horizon size or surface gravity. It was derived that such objects obey a no-force condition. In this short note I present a simplified derivation that is essentially present in the formalism of timelike reduction pioneered by Breitenlohner, Gibbons and Maison. This formalism also provides the natural definition of quasi-extremality for gravitational instantons (and wormholes) sourced by axion fluxes and strengthens the argument that macroscopic axion wormholes do not contribute in the path integral since they are self-repulsive in a Euclidean sense.

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Thomas Van Riet. 2020-10-22. A comment on no-force conditions for black holes and branes. https://doi.org/10.1088/1361-6382%2Fabe01a

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