Entropy, area, and black hole pairs
Abstract
We clarify the relation between gravitational entropy and the area of horizons. We first show that the entropy of an extreme Reissner-Nordström black hole is zero, despite the fact that its horizon has nonzero area. Next, we consider the pair creation of extremal and nonextremal black holes. It is shown that the action which governs the rate of this pair creation is directly related to the area of the acceleration horizon and (in the nonextremal case) the area of the black hole event horizon. This provides a simple explanation of the result that the rate of pair creation of nonextreme black holes is enhanced by precisely the black hole entropy. Finally, we discuss black hole annihilation, and argue that Planck scale remnants are not sufficient to preserve unitarity in quantum gravity.
- Publication:
-
Physical Review D
- Pub Date:
- April 1995
- DOI:
- 10.1103/PhysRevD.51.4302
- arXiv:
- arXiv:gr-qc/9409013
- Bibcode:
- 1995PhRvD..51.4302H
- Keywords:
-
- 04.70.Dy;
- 04.50.+h;
- Quantum aspects of black holes evaporation thermodynamics;
- Gravity in more than four dimensions Kaluza-Klein theory unified field theories;
- alternative theories of gravity;
- General Relativity and Quantum Cosmology;
- High Energy Physics - Theory
- E-Print:
- 25 pages