Related papers: What is the maximum rate at which entropy of a str…

We investigate the inclusion of 10-dimensional string loop corrections to the entropy function of two-charge extremal small black holes of the heterotic string theory compactified on S^1 x T^5 and show that the entropy is given by…

Entropy of all systems that we understand well is proportional to their volumes except for black holes given by their horizon area. This makes the microstates of any quantum theory of gravity drastically different from the ordinary matter.…

Based on well-known properties of semi-classical black holes, we show that weakly-coupled string theory can be viewed as a theory of N = 1/g_s^2 particle species. This statement is a string theoretic realization of the fact that the…

We compare the one-loop corrections to the entropy of a black hole, from quantum fields of spin zero, one-half, and one, to the entropy of entanglement of the fields. For fields of spin zero and one-half the black hole entropy is identical…

Dilatations by means of a constant factor can be seen in a double way: as a simple change of units length or as a conformal mapping of the starting spacetime into a ``stretched'' one with the same units length. The numerical value of the…

One can increase one-quarter the area of a black hole, A/4, to exceed the total thermodynamic entropy, S, by surrounding the hole with a perfectly reflecting shell and adiabatically squeezing it inward. A/4 can be made to exceed S by a…

Using the brick wall method we compute the statistical entropy of a scalar field in a nontrivial background, in two different cases. These background are generated by four and five dimensional black holes with four and three U(1) charges…

This is a short review summarizing the current status of the comparison between microscopic and macroscopic entropy of extremal BPS black holes in string theory.

The entropy of anti-de Sitter Reissner-Nordstrom black hole is found to be stored in the material which gathers to form it and equals to $A/4$ regardless of material states. Extending the study to two kinds of extreme black holes, we find…

We argue that if black hole entropy arises from a finite number of underlying quantum states, then any particular such state can be identified from infinity. The finite density of states implies a discrete energy spectrum, and, in general,…

We argue that on-shell excitations with large negative energies are created rapidly when the string coupling increases with time. This does not indicate an inconsistency in string theory since the negative energy on-shell excitation is…

Considering the entanglement between quantum field degrees of freedom inside and outside the horizon as a plausible source of black hole entropy, we address the question: {\it where are the degrees of freedom that give rise to this entropy…

Quantum aspects of black holes represent an important testing ground for a theory of quantum gravity. The recent success of string theory in reproducing the Bekenstein-Hawking black hole entropy formula provides a link between general…

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…

Effective field theories break down inside large black holes on macroscopic scales when tidal forces are string-sized. If $r_0$ is the horizon radius and $\alpha'$ is the square of the string scale, the 4D Schwarzschild interior is strongly…

The island rule for the entanglement entropy is applied to an eternal Reissner-Nordstr\"om black hole. The key ingredient is that the black hole is assumed to be in thermal equilibrium with a heat bath of an arbitrary temperature and so the…

We evaluate the probability that a loop of string that has spontaneously nucleated during inflation will form a black hole upon collapse, after the end of inflation. We then use the observational bounds on the density of primordial black…

In these lecture notes we describe recent progress in our understanding of attractor mechanism and entropy of extremal black holes based on the entropy function formalism. We also describe precise computation of the microscopic degeneracy…

Black holes are thermodynamic objects, but despite recent progress, the ultimate statistical mechanical origin of black hole temperature and entropy remains mysterious. Here I summarize an approach in which the entropy is viewed as arising…

The rate at which matter flows into a galactic nucleus during early phases of galaxy evolution can sometimes exceed the Eddington limit of the growing central black hole by several orders of magnitude. We discuss the necessary conditions…