Charged Anti-de Sitter Black Holes Research Articles

Thermodynamic features of AdS black holes within the rastall gravity and perfect fluid matter framework

In this study, we analyzed the impact of a perfect fluid on the phase transition of Anti-de Sitter (AdS) black holes within the Rastall gravitational background. Compared to similar studies in the literature, the findings of this work are highlighted by the determination of analytical expressions for critical points for charged and Kerr-Newman AdS black holes using approximated formulas for the horizon radius. An accurate analysis of these new analytical expressions allowed us to discover a new viable condition that relates the Rastall parameter κ λ to the equation of state parameter ω, expressed as: κλ=ω1+ω . Thanks to this new condition, we were able to reproduce all the analytical expressions of critical points calculated within the framework of Einsteinâs general relativity for two cases: a charged AdS black hole and a rotating AdS black hole. These findings suggest that Rastall gravity, considering this new condition, could serve as an alternative theory of gravitation to general relativity. The approximate expression of the horizon radius also enabled the exploration of the distinctiveness of fractional-order phase transitions in these AdS black holes. Furthermore, we calculated the critical exponents, offering insights into the behavior of crucial thermodynamic quantities near the inflection point. Examining how a perfect fluid influences phase transition reveals various critical behaviors, demonstrating that the variation in the phase transition depends on the intensity of the perfect fluid. Notably, this variation is portrayed by a linearly increasing trajectory with the escalation of this intensity.

Critical behavior and Joule-Thomson expansion of charged AdS black holes surrounded by exotic fluid with modified Chaplygin equation of state* *Supported by the Doctoral Foundation of Zunyi Normal University of China (BS [2022]07, QJJ-[2022]-314), and the National Natural Science Foundation of China (12265007, 12264061). The research partially was supported by the Long-Term Conceptual Development of a University of Hradec Králové

By considering the concept of a unified single fluid model, referred to as modified Chaplygin gas (MCG), which amalgamates dark energy and dark matter, we explore the thermodynamic characteristics of charged anti-de Sitter (AdS) black holes existing in an unconventional fluid accompanied by MCG. To accomplish this objective, we derive the equations of state by regarding the charge as a thermodynamic variable. The effects of MCG parameters on the critical thermodynamic quantities ( , , ) are examined, followed by a detailed analysis of the diagram. To provide a clearer explanation of the phase transition, we present an analysis of the Gibbs free energy. It is important to note that if the Hawking temperature exceeds the critical temperature, a distinct pattern is observed known as swallowtail behavior. This indicates that the system undergoes a first-order phase transition from a smaller black hole to a larger one. The critical exponent of the system is found to be in complete agreement with that of the van der Waals fluid system. Furthermore, we investigate the impact of MCG parameters and black hole charge on Joule-Thomson (J-T) expansion in the extended phase space. The J-T coefficient is examined to pinpoint the exact region experiencing cooling or heating, and the observation reveals that the presence of negative heat capacity results in the occurrence of a cooling process. The impact of MCG on the inversion curve of charged black holes exhibits a striking resemblance to that observed in most multi-dimensional black hole systems. In addition, it is worth noting that certain parameters exert a significant influence on the ratio . For specific values of the MCG parameters, the ratio is consistent with the charged AdS black hole. The parameters γ and β have a non-negligible effect on the isenthalpic curve.

Ruppeiner geometry and the fluctuation of the RN-AdS black hole in framework of the extensive thermodynamics

In this study, the Ruppeiner geometry and fluctuations of a four-dimensional charged Anti-de Sitter (AdS) black hole within the context of extensive thermodynamics have been investigated. By fixing the AdS radius in Vissers' construction, an extensive thermodynamics description of the RN-AdS black hole is established, with the central charge playing the role of the particle number, introducing the concept of a subsystem into black hole thermodynamics. By employing the density of thermodynamic variables, the phase transition of the black hole is reexamined, and this result holds for black holes with different AdS backgrounds. Furthermore, the authors delve into a detailed analysis of the Ruppeiner geometry using fluctuation theory. Interestingly, an increase in the particle number of the smaller subsystem is found to induce a reduction in the thermodynamic curvature scalar.

P − v criticalities, phase transitions and geometrothermodynamics of charged AdS black holes from Kaniadakis statistics

Boltzmann entropy-based thermodynamics of charged anti-de Sitter (AdS) black holes has been shown to exhibit physically interesting features, such as P − V criticalities and van der Waals-like phase transitions. In this work we extend the study of these critical phenomena to Kaniadakis theory, which is a non-extensive generalization of the classical statistical mechanics incorporating relativity. By applying the typical framework of condensed-matter physics, we analyze the impact of Kaniadakis entropy onto the equation of state, the Gibbs free energy and the critical exponents of AdS black holes in the extended phase space. Additionally, we investigate the underlying micro-structure of black holes in Ruppeiner geometry, which reveals appreciable deviations of the nature of the particle interactions from the standard behavior. Our analysis opens up new perspectives on the understanding of black hole thermodynamics in a relativistic statistical framework, highlighting the role of non-extensive corrections in the AdS black holes/van der Waals fluids dual picture.

Impact of quintessence and cloud of strings on self-consistent d-dimensional charged thin-shell wormholes

This article evaluates the stability constraints of higher-dimensional geometry of thin-shell wormholes developed from the two equivalent copies of inner and outer d-dimensional charged anti-de Sitter black holes bounded by a cloud of strings and quintessence. Such geometrical structures are built using a cut-and-paste method that joins two identical forms of black hole solutions at the hypersurface. We develop the equation of motion for the constructed wormholes and then use the linear radial perturbation approach to examine the stable configuration. The stability constraints depend on the dimensions of the black holes, cloud, and quintessence parameters. It is worth mentioning that the possibility of a stable structure is greatest for the choice of d-dimensional charged anti-de Sitter black holes with quintessence and a cloud of strings.

Thermal fluctuations, QNMs, and emission energy of charged ADS black hole with nonlinear electrodynamics

This study examines the thermodynamics of charged anti-de Sitter (AdS) black holes (BHs) with nonlinear electrodynamics (NED) using quasinormal modes (QNMs) and thermal fluctuations. For this purpose, we calculate the Hawking temperature and discuss the stable configuration of the considered black hole using heat capacity. First, we study the interesting aspects of the emission of energy. Then, we explore the effects of thermal corrections on thermodynamic quantities and their corrected energies. We study the phase transitions of the system in the background of thermal fluctuations. It is concluded that the presence of a coupling constant enhances the thermodynamically stable configuration of uncharged and charged AdS BH geometries. We highlight that our results are in good agreement with the thermodynamics of the previous black hole solutions and assumptions presented in the literature.

Black hole geometrothermodynamics and critical phenomena: A look from Tsallis entropy-based perspective

We analyze geometrothermodynamics of charged anti-de Sitter (AdS) black holes with a global monopole in the framework of Tsallis statistics. The latter arises from a non-additive generalization of Boltzmann–Gibbs entropy, which is still recovered as a particular sub-case. We examine the effects of Tsallis entropy on small-large black holes phase-transitions and critical exponents, comparing the results with the liquid–gas change of phase occurring in van der Waals fluids. We also discuss some physical constraints on Tsallis parameter and the impact on sparsity of BH radiation. Thermodynamic curvature behavior and the nature of microscopic interactions are then explored from a geometric perspective within Ruppeiner formalism on the S−P coordinate space. Similar considerations are extended to charged (2+1)-dimensional Banados–Teitelboim–Zanelli (BTZ) black holes by computing the entropy-pressure and entropy-volume corrected curvatures. Our analysis shows that Tsallis prescription has non-trivial implications on black hole geometrothermodynamics, emphasizing the role of non-additive entropy in the correspondence between black holes and van der Waals systems.

Critical behavior and Joule–Thomson expansion of charged anti-de Sitter black hole in four-dimensional Rastall gravity

In this work, we investigate the thermodynamics of four-dimensional charged anti-de Sitter (AdS) black hole surrounded by perfect fluids in the context of Rastall theory. We derive the equations of state by considering the charge square [Formula: see text] and the metric parameter [Formula: see text] as the thermodynamic variables. The [Formula: see text] and [Formula: see text] figures for some special surrounding fields were analyzed in detail. To better explain the phase transition, the behavior of the Gibbs free energy is presented. Note that the critical exponents are in perfect agreement with the van der Waals (vdWs) fluid system. In addition, we discuss Joule–Thomson (J-T) expansion in extended phase space. We determine the region where cooling or heating by investigating J-T coefficient. The inversion curves and the isenthalpic curves are plotted in the [Formula: see text] plane. Also, we calculate the minimum inversion temperature [Formula: see text] and find that the ratio [Formula: see text] is independent of the radiation field parameter [Formula: see text].

Bulk-boundary thermodynamic equivalence: a topology viewpoint

Setting the cosmological constant to be dynamical, we study the bulk and boundary thermodynamics of charged Anti-de Sitter black holes. We develop mass/energy formulas in terms of thermodynamic state functions for the extended thermodynamics, mixed thermodynamics, and boundary conformal field theory thermodynamics. We employ the residue method to study the topological properties of the phase transitions. Our analysis reveals that the bulk and boundary thermodynamics are topologically equivalent for both criticalities and first-order phase transitions in the canonical ensembles, as well as for the Hawking-Page(-like) phase transitions in the grand canonical ensembles. Additionally, those three kinds of phase transitions are shown to be distinguished by their unique topological charges. Our results exemplify the gravity-gauge duality in terms of topology.

Thermal fluctuations, quasi-normal modes and phase transition of the charged AdS black hole with perfect fluid dark matter

In this paper, we study thermodynamics, thermal fluctuations, phase transitions and the charged anti-de Sitter black hole surrounded by perfect fluid dark matter. Large black holes are shown to be stable when subject to thermal fluctuations, and we begin by exploring how these fluctuations affect the uncorrected thermodynamic quantities of entropy, Helmholtz free energy, Gibbs free energy, enthalpy specific heat, and phase transition stability. We also discuss null geodesics and the radius of the photon sphere for the charged AdS BH and use the radius of a photon sphere to calculate the Lyapunov exponent and angular velocity. Exceptionally, we test the effects of various parameters of a black hole graphically by observing the existence of the correction parameter and the coupling parameter, which reveal the behavior of corrected thermodynamic quantities. Lastly, we see how the system is stable (under the effects of the dark matter parameter) by figuring out the specific heat and Hawking temperature, which are both related to entropy.

Thermodynamic geometry and universal properties of charged anti-de Sitter black hole immersed in perfect fluid dark matter

Thermodynamic geometry and universal properties of charged anti-de Sitter black hole immersed in perfect fluid dark matter

Rate of the phase transition for a charged anti-de Sitter black hole

Phase transition is a core content of black hole thermodynamics. This study adopted the Kramer’s escape rate method for describing the Brownian motion of particles in an external field to investigate the intensity of the phase transition between small and large black hole states. Some existing studies mostly focused on the formal analysis of the thermodynamic phase transition of black holes, but they neglected the detailed description of the phase transition process. Our results show that the phase transition between small and large black holes for charged anti-de Sitter (AdS) black holes presents serious asymmetric features, and the overall process is dominated by the transition from a small black hole to a large black hole. This study filled a research gap of a stochastic process analysis on the issue of the first-order phase transition rate in the AdS black hole.

Photon orbits and phase transition for non-linear charged anti-de Sitter black holes

In this work, we investigate the relation between the photon sphere radius and the first-order phase transition for the charged Einstein-power-Yang-Mills AdS black hole. Through the analysis, we find with a certain condition there exist the non-monotonic behaviors between the photon sphere radius, the impact parameter, the non-linear Yang-Mills charge parameter, temperature, and pressure. And both the changes of photon sphere radius and impact parameter before and after phase transition can be regarded as the order parameter, their critical exponents near the critical point are equal to the same value 1/2, just like the ordinary thermal systems. These indicate that there maybe exists a universal relation of gravity nearby the critical point for a black hole thermodynamical system. Furthermore, the effect of impact parameter on the deflect angle is also investigated.

Joule–Thomson expansion for a nonlinearly charged Anti-de Sitter black hole

In this work, we examine the Joule–Thomson (JT) expansion for a nonlinearly charged AdS black hole solution. We obtain the expression of the JT coefficient from which we calculate the inversion temperature for numerous values of the charge [Formula: see text]. Moreover, we derive the isenthalpic curve in [Formula: see text] diagram and illustrate the cooling–heating region by the inversion curve for fixed masses. We find that the temperature and pressure on the inversion point decrease with a larger charge [Formula: see text] and increase as the black hole mass grows.

Shadow thermodynamics of non-linear charged Anti-de Sitter black holes* *Supported by the National Natural Science Foundation of China (12075143)

It is well known that when vacuum polarization emerges in quantum electrodynamics, the non-linear interaction between electromagnetic fields should be considered. Moreover, the corresponding field of non-linear electrodynamics can have important effects on black hole physics. In this work, we focus on the relationship between an observable quantity, that is, the shadow radius, and the first-order phase transition of non-linear charged AdS black holes in the framework of Einstein-power-Yang-Mills gravity. The results show that, under a certain condition, there exists a first-order phase transition from the viewpoint of both the shadow radius and horizon radius, which depend on temperature (or pressure). From the viewpoint of the shadow radius, the phase transition temperature is higher than that from the viewpoint of the horizon radius under the same condition. This may be due to the non-linear Yang Mills charge and the gravitational effect. This indicates that the shadow radius can be regarded as a probe to reveal the thermodynamic phase transition information of black holes. The thermal profiles of coexistent large and small black hole phases when the system is undergoing the phase transition are presented for two different values of the non-linear Yang Mills charge parameter: . Furthermore, the effects of the non-linear Yang Mills charge parameter on the shadow radius and thermal profile are investigated.

The microstructure and Ruppeiner geometry of charged anti-de Sitter black holes in Gauss–Bonnet gravity: from the critical point to the triple point

Ruppeiner geometry has been successfully applied in the study of the black hole microstructure by combining with the small–large black hole phase transition, and the potential interactions among the molecular-like constituent degrees of freedom are uncovered. In this paper, we will extend the study to the triple point, where three black hole phases coexist acting as a typical feature of black hole systems quite different from the small–large black hole phase transition. For the six-dimensional charged Gauss–Bonnet anti-de Sitter black hole, we thoroughly investigate the swallow tail behaviors of the Gibbs free energy and the equal area laws. After obtaining the black hole triple point in a complete parameter space, we exhibit its phase structures both in the pressure–temperature and temperature–horizon radius diagrams. Quite different from the liquid–vapor phase transition, a double peak behavior is present in the temperature–horizon radius phase diagram. Then we construct the Ruppeiner geometry and calculate the corresponding normalized curvature scalar. Near the triple point, we observe multiple negatively divergent behaviors. Positive curvature scalar is observed for the small black hole with high temperature, which indicates that the repulsive interaction dominates among the microstructure. Furthermore, we consider the variation of the curvature scalar along the coexisting intermediate and large black hole curves. Combining with the observation for different fluids, the result suggests that this black hole system behaves more like the argon or methane. Our study provides a first and preliminary step towards understanding black hole microstructure near the triple point, as well as uncovering the particular properties of the Gauss–Bonnet gravity.

Topology of black hole thermodynamics

Critical point is an important structure in the phase diagram of a thermodynamic system. In this work, we introduce topology to the study of the black hole thermodynamics for the first time by following Duan's topological current $\phi$-mapping theory. Each critical point is endowed with a topological charge. We find that critical points can be divided into two classes, the conventional and the novel. Further study shows that the first-order phase transition can extend from the conventional critical point, while the present of the novel critical point cannot server as an indicator of the present of the first-order phase transition near it. Moreover, the charged anti-de Sitter black hole and the Born-Infeld anti-de Sitter black hole have different topological charges, which indicates they are in different topological classes from the viewpoint of thermodynamics. These give the first promising study on the topology of the black hole thermodynamics. Such approach is also expected to be extended to other black holes, and much more topological information remains to be disclosed.

Thermodynamics of nonlinearly charged anti–de Sitter black holes in four-dimensional critical gravity

In this work, we provide new examples of Anti-de Sitter black holes with a planar base manifold in four-dimensional Critical Gravity by considering nonlinear electrodynamics as a matter source. We find a general solution characterized by the presence of only one integration constant where, for a suitable election of coupling constants, we can show the existence of one or more horizons. Additionally, we compute its non-null thermodynamical quantities through a variety of techniques, testing the validity of the first law of thermodynamics as well as a Smarr formula. Finally, we analyze the local thermodynamical stability of the solutions. To our knowledge, these charged configurations are the first example with Critical Gravity where their thermodynamical quantities are not zero.

Dynamic property of phase transition for non-linear charged anti-de Sitter black holes * *Supported by the National Natural Science Foundation of China (11705106, 11475107, 12075143), the Natural Science Foundation of Shanxi Province, China (201901D111315), the Natural Science Foundation for Young Scientists of Shanxi Province, China (201901D211441), the Scientific Innovation Foundation of the Higher Education Institutions of Shanxi Province (2020L0471, 2020L0472,

Understanding the thermodynamic phase transition of black holes can provide deep insights into the fundamental properties of black hole gravity and help to establish quantum gravity. In this work, we investigate the phase transition and its dynamics for the charged EPYM AdS black hole. Through reconstructing Maxwell's equal-area law, we find there exists a high-/low-potential black hole (HPBH/LPBL) phase transition, not only the pure large/small black hole phase transition. The Gibbs free energy landscape ( ) is treated as a function of the black hole horizon, which is the order parameter of the phase transition due to thermal fluctuation. From the viewpoint of , the stable HPBH/LPBL states correspond to two wells of , which have the same depth. The unstable intermediate-potential black hole state corresponds to the local maximum of . Then we focus on the probability evolution governed by the Fokker–Planck equation. Through solving the Fokker–Planck equation with different reflection/absorption boundary conditions and initial conditions, the dynamics of switching between the coexistent HPBH and LPBL phases is probed within the first passage time. Furthermore, the effect of temperature on the dynamic properties of the phase transition is also investigated.

Insight into the microscopic structure of a quintessential black hole from the quantization concept

In this work, based on [D.-Q. Sun, J.-B. Deng, P. Li and X.-R. Hu, Class. Quantum Grav. 37, 015008 (2020)], we examine the effect of the quintessence field on the microscopic structure of a charged anti-de Sitter (AdS) black hole from the quantization perspective. Indeed, the impact of the state parameter and the quintessence intensity on “energy quantum” is illustrated. Furthermore, we extend the relationship between the number of quanta of the area and the microscopic degrees of freedom of the black hole to the quintessential background. We express the latent heat in terms of the number of quanta of the area of the large black hole (LBH) and the number of quanta of the area of the small black hole (SBH). Besides that, we explore the connection between the microscopic structure and Ruppeiner geothermodynamics in the (mass, pressure)-plane through the number of quanta of area perspective and the quintessence parameters. Finally, we interpret our result in terms of repulsive/attractive interactions amongst the black hole constituents.