Narrow Results

Back reaction in the Schwarzschild–de Sitter black hole in thermal equilibrium with conformal massless quantum field is discussed using the method of York. The presence of quantum field and back reaction ensures the entropy of dressed black hole. In the perturbed spacetime geometry, the nature of the effective potential and the orbits of massless and massive particles are also investigated.

Hawking radiation from a general Kerr–Newman black hole is investigated using Damour–Ruffini's method. Considering the back-reaction of particle's energy, charge and angular momentum to the spacetime, we obtain a modified nonthermal spectrum. Maybe the information loss paradox can be explained, furthermore, the result is also consistent with the result obtained using Parikh and Wilczek's method.

Black holes have been a subject of investigation over years not only because they have interesting physical properties, but also because they seem to be the appropriate tool for studying gravity in quantum scale. A lot of effort has been made to understand the aspects of spacetime on the quantum scale. Among several possibilities, the approach which includes noncommutativity of spacetime proves to be promising. In this paper, we use the Hamilton–Jacobi method to study the thermodynamic properties of cylindrical black holes (black strings) in noncommutative spacetime. The behavior of the black string is also investigated in the presence of back reaction as well as its influence on the system can be understood as an anomaly. This work aims to provide an understanding about black strings thermodynamics in noncommutative spacetime since this scale of spacetime is important for the comprehension of the relation between quantum mechanics and general relativity.