Horndeski gravity and the violation of reverse isoperimetric inequality

Abstract

We consider Einstein-Horndeski-Maxwell gravity, together with a cosmological constant and multiple Horndeski axions. We construct charged AdS planar black holes in general dimensions where the Horndeski axions span over the planar directions. We analyze the thermodynamics and obtain the black hole volumes. We show that the reverse isoperimetric inequality can be violated, implying that these black holes can store information more efficiently than the Schwarzschild black hole.

Thermodynamic instabilities of generalized exotic BTZ black holes

“…When the equality is saturated, a black hole of a given thermodynamic volues has attained its maximal possible entropy. Since then, the isoperimetric ratio R of various black hole families have been studied, and some were found to violate this inequality [8][9][10][11][12][13][14][15][16]. Such black holes have come to be called super-entropic, since they have more entropy that the relation (1) would admit.…”

Action growth of dyonic black holes and electromagnetic duality

“…This feature is similar to that of Lovelock gravity [58]. A class of black hole solutions were constructed in Horndeski theory in [59,60] and their thermodynamics were studied in [61,62], the instability and holographic applications can be found in [63][64][65][66][67][68][69][70][71][72][73][74][75] and reference therein. In particular it was proposed that the theory is a holographic dual to some scale invariant but not conformal invariant quantum field theory [73,75].…”

Holographic complexity growth rate in Horndeski theory

“…The stability and causality of these black holes were carried out in [42][43][44]. Holographic application of Horndeski theory were investigated in [45][46][47][48][49][50][51][52], especially, it was shown in [51] that although there is no holographic a-theorem for general Horndeski gravity, there does exist a critical point in parameter space where the holographic a-theorem can be achieved, which suggests the Horndeski theory should have a holographic field theory dual. The AdS black holes we studied in this paper are in this critical point.…”