No Arabic abstract
In this paper, the overcharging problem and thermodynamics in the extended phase spaces of the five-dimensional spherically symmetric topological black holes are investigated by absorptions of scalar particles and fermions. The cosmological constant is regarded as a variable related to pressure and its conjugate quantity is a thermodynamic volume. The first law of thermodynamics is recovered. The second law is violated in the extended phase space of the extremal and near-extremal black holes. The overcharging problem is tested by the existence of the event horizons. The event horizon is determined by the metric component $f(r)$. The minimal values of the metric component at the final stage show that the extremal and near-extremal black holes can not be overcharged.
In this paper, we study thermodynamics and phase structure of asymptotically AdS hairy and Reissner-Nordstr{o}m-AdS (RNAdS) black holes in the extended phase space, where the cosmological constant is interpreted as a thermal pressure. The RNAdS and hairy black holes are black hole solutions of an Einstein-Maxwell-scalar (EMS) model with a non-minimal coupling between the scalar and electromagnetic fields. The Smarr relation, the first law of thermodynamics and the free energy are derived for black hole solutions in the EMS model. Moreover, the phase structure of the RNAdS and hairy black holes is investigated in canonical and grand canonical ensembles. Interestingly, RNAdS BH/hairy BH/RNAdS BH reentrant phase transitions, consisting of zeroth-order and second-order phase transitions, are found in both ensembles.
In this paper, we extend the phase space of black holes enclosed by a spherical cavity of radius $r_{B}$ to include $Vequiv4pi r_{B}^{3}/3$ as a thermodynamic volume. The thermodynamic behavior of Schwarzschild and Reissner-Nordstrom (RN) black holes is then investigated in the extended phase space. In a canonical ensemble at constant pressure, we find that the aforementioned thermodynamic behavior is remarkably similar to that of the anti-de Sitter (AdS) counterparts with the cosmological constant being interpreted as a pressure. Specifically, a first-order Hawking-Page-like phase transition occurs for a Schwarzschild black hole in a cavity. The phase structure of a RN black hole in a cavity shows a strong resemblance to that of the van der Waals fluid. Our results may provide a new perspective for the extended thermodynamics of AdS black holes by analogy with black holes in a cavity.
We consider the critical behaviors and phase transitions of Gauss Bonnet-Born Infeld-AdS black holes (GB-BI-AdS) for $d=5,6$ and the extended phase space. We assume the cosmological constant, $Lambda$, the coupling coefficient $alpha$, and the BI parameter $beta$ to be thermodynamic pressures of the system. Having made these assumptions, the critical behaviors are then studied in the two canonical and grand canonical ensembles. We find reentrant and triple point phase transitions (RPT-TP) and multiple reentrant phase transitions (multiple RPT) with increasing pressure of the system for specific values of the coupling coefficient $alpha$ in the canonical ensemble. Also, we observe a reentrant phase transition (RPT) of GB-BI-AdS black holes in the grand canonical ensemble and for $d=6$. These calculations are then expanded to the critical behavior of Born-Infeld-AdS (BI-AdS) black holes in the third order of Lovelock gravity and in the grand canonical ensemble to find a Van der Waals behavior for $d=7$ and a reentrant phase transition for $d=8$ for specific values of potential $phi$ in the grand canonical ensemble. Furthermore, we obtain a similar behavior for the limit of $beta to infty$, i.e charged-AdS black holes in the third order of the Lovelock gravity. Thus, it is shown that the critical behaviors of these black holes are independent of the parameter $beta$ in the grand canonical ensemble.
We study several aspects of the extended thermodynamics of BTZ black holes with thermodynamic mass $M=alpha m + gamma frac{j}{ell}$ and angular momentum $J = alpha j + gamma ell m$, for general values of the parameters $(alpha, gamma)$ ranging from regular ($alpha=1, gamma=0$) to exotic ($alpha=0, gamma=1$). We show that there exist two distinct behaviours for the black holes, one when $alpha > gamma$ (mostly regular), and the other when $gamma < alpha$ (mostly exotic). We find that the Smarr formula holds for all $(alpha, gamma)$. We derive the corresponding thermodynamic volumes, which we find to be positive provided $alpha$ and $gamma$ satisfy a certain constraint. The dependence of pressure on volume is unremarkable and strictly decreasing when $alpha > gamma$, but a maximum volume emerges for large $Jgg T$ when $gamma > alpha$; consequently an exotic black hole of a given horizon circumference and temperature can exist in two distinct anti de Sitter backgrounds. We compute the reverse isoperimetric ratio, and study the Gibbs free energy and criticality conditions for each. Finally we investigate the complexity growth of these objects and find that they are all proportional to the complexity of the BTZ black hole. Somewhat surprisingly, purely exotic BTZ black holes have vanishing complexity growth.
In this paper, we investigate the thermodynamics of dyonic black holes with the presence of power Maxwell electromagnetic field in the extended phase space, which includes the cosmological constant $Lambda$ as a thermodynamic variable. For a generic power Maxwell black hole with the electric charge and magnetic charge, the equation of state is given as the function of rescaled temperature $tilde{T}$ in terms of other rescaled variables $ tilde{r}_{+}$, $tilde{q}$ and $tilde{h}$, where $r_{+}$ is the horizon radius, $q$ is the electric charge and $h$ is some magnetic parameter. For some values of $tilde{q}$ and $tilde{h}$, the phase structure of the black hole is uniquely determined. Moreover the peculiarity of multiple temperature with some fixed parameter configurations results in more rich phase structures. Focusing on the power Maxwell Lagrangian with $mathcal{L} left( sright) =s^{2}$, we obtain the corresponding phase diagrams in the $ tilde{q}$-$tilde{h}$ plane, then analyse the black holes phase structure and critical behaviour. For this case, the critical line is semi-infinite and extends to $tilde{h}=infty$. We also examine thermal stabilities of these black holes.