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Title: Gravitational duals to the grand canonical ensemble abhor Cauchy horizons
A bstract The gravitational dual to the grand canonical ensemble of a large N holographic theory is a charged black hole. These spacetimes — for example Reissner- Nordström-AdS — can have Cauchy horizons that render the classical gravitational dynamics of the black hole interior incomplete. We show that a (spatially uniform) deformation of the CFT by a neutral scalar operator generically leads to a black hole with no inner horizon. There is instead a spacelike Kasner singularity in the interior. For relevant deformations, Cauchy horizons never form. For certain irrelevant deformations, Cauchy horizons can exist at one specific temperature. We show that the scalar field triggers a rapid collapse of the Einstein-Rosen bridge at the would-be Cauchy horizon. Finally, we make some observations on the interior of charged dilatonic black holes where the Kasner exponent at the singularity exhibits an attractor mechanism in the low temperature limit.
Authors:
; ; ;
Award ID(s):
1801805
Publication Date:
NSF-PAR ID:
10287904
Journal Name:
Journal of High Energy Physics
Volume:
2020
Issue:
10
ISSN:
1029-8479
Sponsoring Org:
National Science Foundation
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