A comment on no-force conditions for black holes and branes. (11th March 2021)

• Record Type: Journal Article
• Authors: Van Riet, Thomas
• Is Part Of: Classical and quantum gravity. Volume 38:Number 7(2021)
• Publication Date: 2021-03-11
• Subjects: black holes, black branes, instantons -- black holes -- black branes; Quantum gravity -- Periodicals; Gravitation -- Periodicals; Relativity (Physics) -- Periodicals; Space and time -- Periodicals; Periodicals; 521.1
• DOI: 10.1088/1361-6382/abe01a
• Languages: English
• ISSNs: 0264-9381

Abstract

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.