arXiv subjects

S. H. Hendi

Publications and source records attributed to S. H. Hendi.

At least 37 records · Page 2Linked to original sources

arXiv2020

Three dimensional Lifshitz-like black hole in a special class of F(R) gravity

Regarding a special class of pure F(R) gravity in three dimensions, we obtain, analytically, Lifshitz-like black hole solutions. We check the geometrical properties of the solutions which behave such as charged BTZ black holes in special limit. We also investigate the thermodynamic properties of the solutions and examine the first law of thermodynamics and Smarr formula. In addition, we study thermal stability via the heat capacity and discuss the possibility of criticality in the extended phase space.

gr-qc↗

arXiv2020

Thermodynamics, shadow and quasinormal modes of black holes in five-dimensional Yang-Mills massive gravity

In this paper, we consider the Einstein-massive gravity coupled to the Yang-Mills gauge field in five dimensions. Concentrating on the static solutions with planar horizon geometry, we explore the thermodynamic behavior in the extended phase space and examine the validity of the first law of thermodynamics besides local thermal stability by the Hessian matrix. We observe that although the topology of boundary is planar, there exists the van der Waals like phase transition for this kind of solution. We find the critical quantities and discuss how the massive and Yang-Mills parameters affect them. Furthermore, some signatures of the first order phase transition such as the swallow-tail behavior of the Gibbs free energy and divergences of the specific heat are given in detail. We continue with the calculation of the photon sphere and the shadow observed by a distant observer. Finally, we use the WKB method to investigate the quasinormal modes for scalar perturbation under changing the massive and Yang-Mills parameters.

hep-th↗

arXiv2020

Dynamical and Thermal Stabilities of Nonlinearly Charged AdS Black Holes

In this paper, we study an extended phase space thermodynamics of a nonlinearly charged AdS black hole. We examine both the local and global stabilities, and possible phase transition of the black hole solutions. Finally, we compute quasi-normal modes via scalar perturbations and compare the obtained results with those of RN-AdS black hole.

gr-qc↗

arXiv2020

Simulation of geodesic trajectory of charged BTZ black holes in massive gravity

In order to classify and understand the spacetime structure, investigation of the geodesic motion of massive and massless particles is a key tool. So the geodesic equation is a central equation of gravitating systems and the subject of geodesics in the black hole dictionary attracted much attention. In this paper, we give a full description of geodesic motions in three-dimensional spacetime. We investigate the geodesics near charged BTZ black holes and then generalize our prescriptions to the case of massive gravity. We show that electric charge is a critical parameter for categorizing the geodesic motions of both lightlike and timelike particles. In addition, we classify the type of geodesics based on the particle properties and geometry of spacetime.

gr-qc↗

arXiv2020

Black Hole Remnant in Massive Gravity

The possibility of a nonzero graviton mass has been widely pursued in the literature. In this work we investigate a black hole solution in massive gravity with a degenerate fiducial metric often used in the literature. We find that the end state of Hawking evaporation leads to black hole remnant, which could help to ameliorate the information paradox. We prove that these remnants only exist in anti-de Sitter spacetime. Nevertheless, we speculate on their possible relevance to our Universe as dark matter candidate, in view of the possibility that our Universe could be inherently anti-de Sitter-like, with a transient accelerated expansion phase.

gr-qc↗

arXiv2019

Thermal stability of a special class of black hole solutions in F(R) gravity

In this paper, we work on the topological Lifshitz-like black hole solutions of a special class of vacuum $F(R)-$gravity that are static and spherically symmetric. We investigate geometric and thermodynamic properties of the solutions with due respect to the validity of the first law of thermodynamics. We examine the van der Waals like behavior for asymptotically AdS solutions with spherical horizon by studying the $P-v$, $G-T$ and $C_{Q,P}-r_{+}$ diagrams and find a consistent result. We also investigate the same behavior for hyperbolic horizon and interestingly find that the system under study can experience a phase transition with negative temperature.

gr-qc↗

arXiv2019

Black hole solutions correspondence between conformal and massive theories of gravity

In this work, a correspondence between black hole solutions of conformal and massive theories of gravity is found. It is seen that this correspondence imposes some constraints on parameters of these theories. What is more, a relation between the mass of black holes and the parameters of massive gravity is found. Indeed, the acceptable ranges of massive gravity parameters ($c_{1}$\ and $c_{2}$) are found. It is shown that by considering the positive mass of black holes, some ranges of $c_{1}$\ and $c_{2}$ are acceptable.

gr-qc↗

arXiv2019

Metamaterials mimic the black holes: the effects of charge and rotation on the optical properties

Motivated by investigation of black hole properties in the lab, some interesting subjects such as analogue gravity and transformation optics are generated. In this paper, we look for the analogies between the geometry of a gravitating system and the optical medium. In addition, we recognize that appropriate metamaterials can be used to mimic the propagation of light in the curved spacetimes and behave like black holes. The resemblance of metamaterials with Kerr and Reissner-Nordström spacetimes is studied. At last, we compare the full-wave numerical calculation of light with its optical limit of geometry.

physics.gen-ph↗

arXiv2019

Entropy spectrum of charged BTZ black holes in massive gravity's rainbow

Regarding the significant interests in massive gravity and combining it with gravity's rainbow and also BTZ black holes, we apply the formalism introduced by Jiang and Han in order to investigate the quantization of the entropy of black holes. We show that the entropy of BTZ black holes in massive gravity's rainbow is quantized with equally spaced spectra and it depends on the black holes' properties including massive parameters, electrical charge, the cosmological constant and also rainbow functions. In addition, we show that quantization of the entropy results into the appearance of novel properties for this quantity such as; the existence of divergencies, non-zero entropy in vanishing horizon radius and possibility of tracing out the effects of black holes' properties. Such properties are absent in the non-quantized version of these black holes' entropy. Furthermore, we investigate the effects of quantization on the thermodynamical behavior of the solutions. We confirm that due to quantization, novel phase transitions points are introduced and stable solutions are limited to only dS black holes (AdS and asymptotically flat solutions are unstable).

hep-th↗

arXiv2018

$AdS_{4}$ dyonic black holes in gravity's rainbow

In this paper, we investigate thermodynamical structure of dyonic black holes in the presence of gravity's rainbow. We confirm that for super magnetized and highly pressurized scenarios, the number of black holes' phases is reduced to a single phase. In addition, due to specific coupling of rainbow functions, it is possible to track the effects of temporal and spatial parts of our setup on thermodynamical quantities/behaviors including equilibrium point, existence of multiple phases, possible phase transitions and conditions for having a uniform stable structure.

gr-qc↗

arXiv2018

Complexity of the Einstein-Born-Infeld-Massive Black holes

Motivated by interesting correspondence between computational complexity in a CFT and the action evaluated on a WDW patch in the bulk, we study the complexity of the Einstein-massive black holes in the presence of BI nonlinear electrodynamics. The upper limit of Llyod bound according to the WDW patch is investigated and it is proved that Llyod bound is held.

gr-qc↗

arXiv2018

Energy-dependent topological anti-de Sitter black holes in Gauss-Bonnet Born-Infeld gravity

Employing higher curvature corrections to Einstein--Maxwell gravity has garnered a great deal of attention motivated by the high energy regime in quantum nature of black hole physics. In addition, one may employ gravity's rainbow to encode quantum gravity effects into the black hole solutions. In this paper, we regard an energy dependent static spacetime with various topologies and study its black hole solutions in the context of Gauss--Bonnet Born--Infeld (GB--BI) gravity. We study thermodynamic properties and examine the first law of thermodynamics. Using suitable local transformation, we endow the Ricci--flat black hole solutions with a global rotation and study the effects of rotation on thermodynamic quantities. We also investigate thermal stability in canonical ensemble through calculating the heat capacity. We obtain the effects of various parameters on the horizon radius of stable black holes. Finally, we discuss second order phase transition in the extended phase space thermodynamics and investigate the critical behavior.

hep-th↗

arXiv2018

New aspect of critical nonlinearly charged black hole

The motion of a point charged particle moving in the background of the critical power Maxwell charged AdS black holes, in a probe approximation is studied. The extended phase space, where the cosmological constant appears as a pressure, is regarded and the effective potential is investigated. At last, the mass-to-charge ratio and the large q limit are studied.

gr-qc↗

arXiv2018

Black hole solutions in Gauss-Bonnet-massive gravity in the presence of power-Maxwell field

Motivated by recent progresses in the field of massive gravity, the paper at hand investigates the thermodynamical structure of black holes with three specific generalizations: i) Gauss-Bonnet gravity which is motivated from string theory ii) PMI nonlinear electromagnetic field which is motivated from perspective of the QED correction iii) massive gravity which is motivated by obtaining the modification of standard general relativity. The exact solutions of this setup are extracted which are interpreted as black holes. In addition, thermodynamical quantities of the solutions are calculated and their critical behavior are studied. It will be shown that although massive and Gauss-Bonnet gravities are both generalizations in gravitational sector, they show opposing effects regarding the critical behavior of the black holes. Furthermore, a periodic effect on number of the phase transition is reported for variation of the nonlinearity parameter and it will be shown that for super charged black holes, system is restricted in a manner that prevents it to reach the critical point and acquires phase transition. In addition, the effects of geometrical structure on thermodynamical phase transition will be highlighted.

hep-th↗

arXiv2018

Gauss-Bonnet Dyonic Black Holes: geometry, thermodynamics and test particles' trajectories

In this paper, we investigate a class of $5$-dimensional black holes in the presence of Gauss-Bonnet gravity with dyonic charges. At first step, thermodynamical quantities of the black holes and their behaviors are explored for different limits. Thermal stability and the possibility of the van der Waals like phase transition are addressed and the effects of different parameters on them are investigated. The second part is devoted to simulation of the trajectory of particles around these black holes and investigation of the angular frequency of particles' motion. The main goal is understanding the effects of higher curvature gravity (Gauss-Bonnet gravity) and magnetic charge on the structure of black holes and the geodesic paths of particles moving around these black holes.

gr-qc↗

arXiv2017

Phase transition of black holes in Brans--Dicke Born--Infeld gravity through geometrical thermodynamics

Using the geometrical thermodynamic approach, we study phase transition of Brans--Dicke Born--Infeld black holes. We apply introduced methods and describe their shortcomings. We also use the recently proposed new method and compare its results with those of canonical ensemble. By considering the new method, we find that its Ricci scalar diverges in the places of phase transition and bound points. We also show that the bound point can be distinguished from the phase transition points through the sign of thermodynamical Ricci scalar around its divergencies.

hep-th↗

arXiv2017

Holographical aspects of dyonic black holes: Massive gravity generalization

The content of this paper includes studying holographical and thermodynamical aspects of dyonic black holes in the presence of massive gravity. For the first part of paper, thermodynamical properties of the bulk which includes black holes are studied and the main focus is on critical behavior. It will be shown that the existence of massive gravitons introduces remnant for temperature after evaporation of black holes, van der Waals phase transition for non-spherical black holes and etc. The consistency of different thermodynamical approaches toward critical behavior of the black holes is presented and the physical properties near the region of thermal instability are given. Next part of the paper studies holographical aspects of the boundary theory. Magnetization and susceptibility of the boundary are extracted and the conditions for having diamagnetic and paramagnetic behaviors are investigated. It will be shown that generalization to massive gravity results into the existence of diamagnetic/paramagnetic phases in phase structure of the hyperbolic and horizon flat of boundary conformal field theory.

hep-th↗

arXiv2017

Three dimensional magnetic solutions in massive gravity with (non)linear field

The Noble Prize in physics 2016 motivates one to study different aspects of topological properties and topological defects as their related objects. Considering the significant role of the topological defects (especially magnetic strings) in cosmology, here, we will investigate three dimensional horizonless magnetic solutions in the presence of two generalizations: massive gravity and nonlinear electromagnetic field. The effects of these two generalizations on properties of the solutions and their geometrical structure are investigated. The differences between de Sitter and anti de Sitter solutions are highlighted and conditions regarding the existence of phase transition in geometrical structure of the solutions are studied.

gr-qc↗