A Lovelock black hole bestiary

Abstract:We investigate entanglement entropy in Gauss-Bonnet gravity following a global quench. It is known that in dynamical scenarios the entanglement entropy probe penetrates the apparent horizon. The goal of this work is to study how far behind the horizon can the entanglement probe reach in a Gauss-Bonnet theory. We find that the behavior is quite different depending on the sign of the Gauss-Bonnet coupling λ GB . For λ GB > 0 the behavior of the probes is just as in Einstein gravity; the probes do not reach the singularity but asymptote to a locus behind the apparent horizon. We calculate the minimum radial position r min reached by the probes and show that for λ GB > 0 they explore less of the spacetime behind the horizon than in Einstein gravity. On the other hand, for λ GB < 0 the results are strikingly different; for early times a new family of solutions appears. These new solutions reach arbitrarily close to the singularity. We calculate the entanglement entropy for the two family of solutions with λ GB < 0 and find that the ones that reach the singularity are the ones of less entanglement entropy. Thus, for λ GB < 0 the holographic entanglement entropy probes further behind the horizon than in Einstein gravity. In fact, for early times it can explore all the way to the singularity.

Section: Jhep09(2017)127mentioning

confidence: 87%

“…They are free of pathologies and are solvable. In fact, many black hole solutions with AdS asymptotics are known [34].…”

Section: Jhep09(2017)127mentioning

confidence: 99%

Holographic entanglement entropy in time dependent Gauss-Bonnet gravity

Cáceres

Sanchez

Virrueta

2017

“…Maximal temperature for the thermalon happens when the mass of the interior spherically symmetric black hole with dS asymptotics reaches its upper bound given by the Nariai threshold [24]. The black hole with dS asymptotics inside the bubble may have negative specific heat when measured by the inner parameters M − and β − (see figure 3; dashed line).…”

Section: Jhep10(2015)179mentioning

confidence: 99%

“…Among them, Lovelock theories play a prominent role since they yield second-order field equations (see [24,25] for a recent review). Thereby, they provide a specially suitable and tractable playground that captures many important features that are rather generic in the context of higher-curvature gravities.…”

Section: Introductionmentioning

confidence: 99%

On AdS to dS transitions in higher-curvature gravity

Camanho

Edelstein

Gomberoff

et al. 2015

Abstract:We study the possible existence of gravitational phase transitions from AdS to dS geometries in the context of higher-curvature gravities. We use Lanczos-Gauss-Bonnet (LGB) theory with a positive cosmological constant as a toy model. This theory has two maximally symmetric vacua with positive (dS) and negative (AdS) constant curvature. We show that a phase transition from the AdS vacuum to a dS black hole geometry takes place when the temperature reaches a critical value. The transition is produced by nucleation of bubbles of the new phase that expand afterwards. We claim that this phenomenon is not particular to the model under study, that contains Boulware-Deser instabilities, but shall also be part of generic gravitational theories with higher-curvature terms, where these problems are absent. A salient feature that emerges when a positive cosmological constant is considered is that the temperature in which these bubbles may form is bounded from above. Thermodynamically this property is related to quite an uncommon feature that this system exhibits, namely, the existence of a zeroth-order phase transition.

“…A property that is shared by its cubic counterpart. It's important to notice that Quartic Quasi-topological gravity in five dimensions does not belong to the family defined in equation (1.2), nevertheless on spherically symmetric spacetimes, the field equations are simple and reduce to a generalized Wheeler-like polynomial equation for the lapse function [15] (see also [16]). The authors of [14] also conjecture the existence of quasi-topological gravities of arbitrarily high degree in the curvature.…”

Section: Jhep04(2017)066mentioning

confidence: 99%

Quintic quasi-topological gravity

Cisterna

Guajardo

Hassaı̈ne

et al. 2017

We construct a quintic quasi-topological gravity in five dimensions, i.e. a theory with a Lagrangian containing R 5 terms and whose field equations are of second order on spherically (hyperbolic or planar) symmetric spacetimes. These theories have recently received attention since when formulated on asymptotically AdS spacetimes might provide for gravity duals of a broad class of CFTs. For simplicity we focus on five dimensions. We show that this theory fulfils a Birkhoff's Theorem as it is the case in Lovelock gravity and therefore, for generic values of the couplings, there is no s-wave propagating mode. We prove that the spherically symmetric solution is determined by a quintic algebraic polynomial equation which resembles Wheeler's polynomial of Lovelock gravity. For the black hole solutions we compute the temperature, mass and entropy and show that the first law of black holes thermodynamics is fulfilled. Besides of being of fourth order in general, we show that the field equations, when linearized around AdS are of second order, and therefore the theory does not propagate ghosts around this background. Besides the class of theories originally introduced in arXiv:1003.4773, the general geometric structure of these Lagrangians remains an open problem.