The expectation value of the stress-energy tensor 〈Tμν〉 of a free conformally invariant scalar field is computed in a general static two-dimensional black hole spacetime when the field is in either a zero temperature vacuum state or a thermal state at a nonzero temperature. It is found that for every static two-dimensional black hole the stress-energy diverges strongly on the event horizon unle...

In recent years there has been some progress in the understanding of the global structure of stationary black hole space–times. In this paper we review some new results concerning the structure of stationary black hole space–times. In particular we prove a corrected version of the “black hole rigidity theorem”, and we prove a uniqueness theorem for static black holes with degenerate connected h...

We study static black hole solutions in Einstein and Einstein–Gauss–Bonnet gravity with the topology of the product of two spheres,Sn × Sn, in higher dimensions. There is an unusual new feature of the Gauss–Bonnet black hole: the avoidance of a non-central naked singularity prescribes a mass range for the black hole in terms of > 0. For an Einstein–Gauss–Bonnet black hole a limited window of ne...

We discuss the macroscopic quantum tunneling from black hole to white of same mass. Previous calculations in Ref.[1] demonstrated that probability is $p \propto \exp(-2S_\text{BH})$, where $S_\text{BH}$ entropy Schwarzschild hole. This particular suggests with minus sign hole, $S_\text{WH}(M)=- S_\text{BH}(M)= - A/(4G)$. Here we use a different way calculations. consider three types objects: an...

We study static brane configurations in the bulk background of the topological black holes in asymptotically flat spacetime. We find that such configurations are possible even for flat black hole horizon, unlike the AdS black hole case. We construct the brane world model with an orbifold structure S/Z2 in such bulk background. We also study massless bulk scalar field.

We construct a new class of asymptotically flat black hole solutions in EinsteinYang-Mills and Einstein-Yang-Mills-dilaton theory. These black hole solutions are static, and they have a regular event horizon. However, they possess only axial symmetry. Like their regular counterparts, the black hole solutions are characterized by two integers, the winding number n and the node number k of the ga...

It is shown analytically that the Dirac equation has no normalizable, time-periodic solutions in a Reissner-Nordström black hole background; in particular, there are no static solutions of the Dirac equation in such a background metric. The physical interpretation is that Dirac particles can either disappear into the black hole or escape to infinity, but they cannot stay on a periodic orbit aro...

We consider a static, spherically symmetric system of a Dirac particle in a classical gravitational and SU(2) Yang-Mills field. We prove that the only black-hole solutions of the corresponding Einstein-Dirac-Yang/Mills equations are the Bartnik-McKinnon black-hole solutions of the SU(2) Einstein-Yang/Mills equations; thus the spinors must vanish identically. This indicates that the Dirac partic...

We consider a static brane in the background of a topological black hole, in arbitrary dimensions. For hyperbolic horizons, we find a solution only when the black hole mass assumes its minimum negative value. In this case, the tension of the brane vanishes, and the brane position coincides with the location of the horizon. For an elliptic horizon, we show that the massless mode of Randall-Sundr...