Journal of Holography Applications in Physics
Volume:2 Issue: 2, Spring 2022

In this work, we explore the holographic entanglement entropy with an infinite strip region of the boundary in Horndeski gravity. In our prescription we consider the spherically and planar topologies black holes in the AdS$_{4}$/CFT$_{3}$ scenario. In such framework, we show the behavior of the entanglement entropy in function of the Horndeski parameters. Such parameters modify the information store of subsystem A, especially when the parameter $gamma$ increases the information about the subsystem will also increase or decrease when it decreases. Thus, with this scheme we compute the “first law of entanglement thermodynamics” in Horndeski gravity and we show that a very small subsystem obeys the analogous property of the first law of thermodynamics if we excite the system.

We study two entropies of a system composed of two coupled harmonic oscillators which isbrought to a canonical thermal equilibrium with a heat-bath at temperature T . Using the purityfunction, we explicitly determine the Rényi and van Newmon entropies in terms of different physicalparameters. We will numerically analyze these two entropies under suitable conditions and showtheir relevance.

In this paper, we aim to explore the impact of the Planck scale corrections and the Holographic quintessence on the shadow behavior of non-rotating black holes. To do this, we consider the quantum-corrected Schwarzschild black hole surrounded by the quintessence field inspired by the Kazakov-Solodukhin and the Kiselev ideas, and we call this combination the Kazakov-Solodukhin-Kiselev (KSK) black hole. We conclude that the quintessence field as the candidate of dark energy in the black hole can be interpreted as Holographic quintessence. To find the geodesic equations of the black hole, we employ the Hamilton-Jacobi approach and also, the Carter procedure. We discover that the size of the shadow of this black hole, which depends on its central mass, is also determined by the Planck scale effects and Holographic quintessence.

In this paper, we investigate special points in which poles of the Green’s function of the D3/D7 branes are skipping. The system that we consider is 〖SU(N〗_c) N=4 SYM theory coupled to N_f flavors N=2 hypermultplets. We fluctuate the scalar field and find that there is no such special values of frequency and momentum to skip the poles. This behavior is different than scalar field in the AdS black brane background.

In this letter we choose generalized Ayon Beato Gracia (ABG)magnetic charged black hole with five parameters to investigatepossibility of thermodynamic phase transition and coexistence ofdifferent gass/liquid/solid phases of this black hole. In factthis work is an extension of our recently work where ABG blackhole with three parameters was used to seek the phase transition.In this work we obtain other physical values on the parameterswith respect to our previous work where the phase transition ishappened together with coexistence point of different phases inthe phase space.

Strongly coupled field theory can be described by calculation of η/s from fluid-gravity duality since this value is proportional to the inverse square coupling of field theory. This ratio should be larger than η/s≥1/4π and it is known as a conjecture in the literature. We calculate the ratio of shear viscosity per entropy density for a dilaton black brane in AdS spacetime. Our result shows that this bound is saturated in this black brane and the field theory dual of our model is the same as field theory dual Einstein gravity.