Black hole horizons at the extremal limit in Lorentz-violating gravity

Lorentz-violating gravity theories with a preferred foliation can have instantaneous propagation. Nonetheless, it has been shown that black holes can still exist in such theories and the relevant notion of an event horizon has been dubbed “universal horizon.” In stationary spacetimes the universal h...

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Main Authors: Franchini, Nicola, Saravani, Mehdi, Sotiriou, Thomas P.
Format: Article
Published: American Physical Society 2017
Online Access:https://eprints.nottingham.ac.uk/48718/
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author Franchini, Nicola
Saravani, Mehdi
Sotiriou, Thomas P.
author_facet Franchini, Nicola
Saravani, Mehdi
Sotiriou, Thomas P.
author_sort Franchini, Nicola
building Nottingham Research Data Repository
collection Online Access
description Lorentz-violating gravity theories with a preferred foliation can have instantaneous propagation. Nonetheless, it has been shown that black holes can still exist in such theories and the relevant notion of an event horizon has been dubbed “universal horizon.” In stationary spacetimes the universal horizon has to reside in a region of spacetime where the Killing vector associated with stationarity is spacelike. This raises the question of what happens to the universal horizon in the extremal limit, where no such region exists anymore. We use a decoupling limit approximation to study this problem. Our results suggest that at the extremal limit, the extremal Killing horizon appears to play the role of a degenerate universal horizon, despite being a null and not a spacelike surface, and hence not a leaf of the preferred foliation.
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spelling nottingham-487182020-05-04T19:19:27Z https://eprints.nottingham.ac.uk/48718/ Black hole horizons at the extremal limit in Lorentz-violating gravity Franchini, Nicola Saravani, Mehdi Sotiriou, Thomas P. Lorentz-violating gravity theories with a preferred foliation can have instantaneous propagation. Nonetheless, it has been shown that black holes can still exist in such theories and the relevant notion of an event horizon has been dubbed “universal horizon.” In stationary spacetimes the universal horizon has to reside in a region of spacetime where the Killing vector associated with stationarity is spacelike. This raises the question of what happens to the universal horizon in the extremal limit, where no such region exists anymore. We use a decoupling limit approximation to study this problem. Our results suggest that at the extremal limit, the extremal Killing horizon appears to play the role of a degenerate universal horizon, despite being a null and not a spacelike surface, and hence not a leaf of the preferred foliation. American Physical Society 2017-11-28 Article PeerReviewed Franchini, Nicola, Saravani, Mehdi and Sotiriou, Thomas P. (2017) Black hole horizons at the extremal limit in Lorentz-violating gravity. Physical Review D, 96 (10). 104044/1-104044/11. ISSN 2470-0029 https://journals.aps.org/prd/abstract/10.1103/PhysRevD.96.104044 doi:10.1103/PhysRevD.96.104044 doi:10.1103/PhysRevD.96.104044
spellingShingle Franchini, Nicola
Saravani, Mehdi
Sotiriou, Thomas P.
Black hole horizons at the extremal limit in Lorentz-violating gravity
title Black hole horizons at the extremal limit in Lorentz-violating gravity
title_full Black hole horizons at the extremal limit in Lorentz-violating gravity
title_fullStr Black hole horizons at the extremal limit in Lorentz-violating gravity
title_full_unstemmed Black hole horizons at the extremal limit in Lorentz-violating gravity
title_short Black hole horizons at the extremal limit in Lorentz-violating gravity
title_sort black hole horizons at the extremal limit in lorentz-violating gravity
url https://eprints.nottingham.ac.uk/48718/
https://eprints.nottingham.ac.uk/48718/
https://eprints.nottingham.ac.uk/48718/