Related papers: Finite Black Hole Entropy and String Theory
A quantum Schwarzschild black hole is described, at the mini super spacetime level, by a non-singular wave packet composed of plane wave eigenstates of the momentum Dirac-conjugate to the mass operator. The entropy of the mass spectrum…
After a brief review of Goedel-type universes in string theory, we discuss some intriguing properties of black holes immersed in such backgrounds. Among these are the upper bound on the entropy that points towards a finite-dimensional…
Using a unified approach we study the entropy of extremal black holes through the entropy of an electrically charged thin shell. We encounter three cases in which a shell can be taken to its own gravitational or horizon radius and become an…
We review recent progress in our understanding of the physics of black holes. In particular, we discuss the ideas from string theory that explain the entropy of black holes from a counting of microstates of the hole, and the related…
A six-dimensional black string is considered and its Bekenstein-Hawking entropy computed. It is shown that to leading order above extremality, this entropy precisely counts the number of string states with the given energy and charges. This…
The concept of black hole entropy is one of the most important enigmas of theoretical physics. It relates thermodynamics to gravity and allows substantial hints toward a quantum theory of gravitation. Although Bekenstein conjecture…
The thermodynamic properties of self-gravitating spherical thin matter shells an black holes in $d>4$ dimensions are studied, extending previous analysis for $d=4$. The shell joins a Minkowski interior to a Tangherlini exterior, i.e., a…
In this Chapter we would like to review a "~phenomenological~" approach taking into account the most fundamental feature of string theory or, more in general, of quantum gravity, whatever its origin, which is the existence of a minimal…
The thermodynamical one-loop entropy $S^{TD}$ of a two-dimensional black hole in thermal equilibrium with the massless quantum gas is calculated. It is shown that $S^{TD}$ includes the Bekenstein-Hawking entropy, evaluated for the quantum…
Solutions to low energy string theory describing black holes and black strings are reviewed. Many of these solutions can be obtained by applying simple solution generating transformations to the Schwarzschild metric. In a few cases, the…
The entropy of a Schwarzschild black hole, as computed via the semiclassical Euclidean path integral in a stationary phase approximation, is determined not by the on-shell value of the action (which vanishes), but by the…
Adopting the thin-layer improved brick-wall method, we investigate the thermodynamics of a black hole embedded in a spatially flat Friedmann-Robertson-Walker universe. We calculate the temperature and the entropy at every apparent horizon…
We argue that the entropy of a black hole is due to the entanglement of matter fields and gravitons across the horizon. While the entanglement entropy of the vacuum is divergent because of UV correlations, we show that low-energy…
The entropy of extremal black holes (BHs) is obtained using a continuity argument from extremal quasiblack holes (QBHs). It is shown that there exists a smooth limiting transition in which (i) the system boundary approaches the extremal…
A black hole considered as a part of a thermodynamical system possesses the Bekenstein-Hawking entropy $S_H =A_H /(4l_{\mbox{\scriptsize{P}}}^2)$, where $A_H$ is the area of a black hole surface and $l_{\,\mbox{\scriptsize{P}}}$ is the…
The first part of this work provides a review of recent research on generalised entropies and their origin, as well as its application to black hole thermodynamics. To start, it is shown that the Hawking temperature and the…
The generalized second law states the total entropy of any closed system as the universe cannot decrease if we include black hole entropy. From the point of view of an asymptotic observer, a black hole can be described at late time as an…
In this work, incorporating the effect of the minimum measurable in momentum and maximal length, we studied thermodynamics property of Schwarzschild black hole and the Unruh effect. {\color{red} According to this scenario, we see that the…
It is shown that three-dimensional charged black holes can approach the extreme state at nonzero temperature. Unlike even dimensional cases, the entropy for the extreme three-dimensional charged black hole is uniquely described by the…
Not only is the Bekenstein expression for the entropy of a black hole a convex function of the energy, rather than being a concave function as it must be, it predicts a final equilibrium temperature given by the harmonic mean. This violates…