Black hole entropy in diffeomorphism-invariant nonminimal gravity decomposes as S_H = S_W + S_1 + ΔS, with the extra terms required for bumblebee and Weyl-vector Gauss-Bonnet solutions but not for regular Kalb-Ramond branches.
Black Hole Entropy and Viscosity Bound in Horndeski Gravity
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
Horndeski gravities are theories of gravity coupled to a scalar field, in which the action contains an additional non-minimal quadratic coupling of the scalar, through its first derivative, to the Einstein tensor or the analogous higher-derivative tensors coming from the variation of Gauss-Bonnet or Lovelock terms. In this paper we study the thermodynamics of the static black hole solutions in $n$ dimensions, in the simplest case of a Horndeski coupling to the Einstein tensor. We apply the Wald formalism to calculate the entropy of the black holes, and show that there is an additional contribution over and above those that come from the standard Wald entropy formula. The extra contribution can be attributed to unusual features in the behaviour of the scalar field. We also show that a conventional regularisation to calculate the Euclidean action leads to an expression for the entropy that disagrees with the Wald results. This seems likely to be due to ambiguities in the subtraction procedure. We also calculate the viscosity in the dual CFT, and show that the viscosity/entropy ratio can violate the $\eta/S\ge 1/(4\pi)$ bound for appropriate choices of the parameters.
fields
gr-qc 4verdicts
UNVERDICTED 4representative citing papers
Bumblebee gravity coupled to NLED yields charged black hole solutions that become regular and horizonless when mass and charge are tuned to specific functions of the couplings.
Exact black hole solutions with topological horizons are found in EKR gravity and their thermodynamics are analyzed using the Wald formalism for mass and entropy.
Background subtraction for black hole thermodynamics is valid and equivalent to Iyer-Wald in matter-coupled gravity theories, with smooth performance in examples but subtleties for certain matter fields.
citing papers explorer
-
Black Hole Entropy Beyond the Wald Term in Nonminimally Coupled Gravity: A Covariant Phase Space Decomposition
Black hole entropy in diffeomorphism-invariant nonminimal gravity decomposes as S_H = S_W + S_1 + ΔS, with the extra terms required for bumblebee and Weyl-vector Gauss-Bonnet solutions but not for regular Kalb-Ramond branches.
-
When Bumblebee Meets NLED: Lorentz-Violating Black Holes and Regular Spacetimes
Bumblebee gravity coupled to NLED yields charged black hole solutions that become regular and horizonless when mass and charge are tuned to specific functions of the couplings.
-
Revisiting black holes and their thermodynamics in Einstein-Kalb-Ramond gravity
Exact black hole solutions with topological horizons are found in EKR gravity and their thermodynamics are analyzed using the Wald formalism for mass and entropy.
-
Validity of the Background Subtraction Method for Black Hole Thermodynamics in Matter-Coupled Gravity Theories
Background subtraction for black hole thermodynamics is valid and equivalent to Iyer-Wald in matter-coupled gravity theories, with smooth performance in examples but subtleties for certain matter fields.