How many black holes fit on the head of a pin?
- 208 Downloads
The Bekenstein–Hawking entropy of certain black holes can be computed microscopically in string theory by mapping the elusive problem of counting microstates of a strongly gravitating black hole to the tractable problem of counting microstates of a weakly coupled D-brane system, which has no event horizon, and indeed comfortably fits on the head of a pin. We show here that, contrary to widely held beliefs, the entropy of spherically symmetric black holes can easily be dwarfed by that of stationary multi-black-hole “molecules” of the same total charge and energy. Thus, the corresponding pin-sized D-brane systems do not even approximately count the microstates of a single black hole, but rather those of a zoo of entropically dominant multicentered configurations.
- 1.Wald, R.M.: The thermodynamics of black holes. Living Rev. Relat. 4, 6 (2001) http://relativity.livingreviews.org/Articles/lrr-2001-6/Google Scholar
- 2.Damour, T.: The entropy of black holes: A primer. arXiv:hep-th/0401160Google Scholar
- 4.Maldacena, J.M., Strominger, A., Witten E.: Black hole entropy in M-theory. JHEP 9712, 002 (1997) (arXiv:hep-th/9711053)Google Scholar
- 8.Denef, F., Moore, G.W.: Split states, entropy enigmas, holes and halos. arXiv:hep-th/0702146Google Scholar
- 12.Denef, F.: Supergravity flows and D-brane stability. JHEP 0008, 050 (2000) (arXiv:hep-th/0005049)Google Scholar
- 13.Lopes Cardoso, G., de Wit, B., Kappeli, J., Mohaupt, T.: Stationary BPS solutions in N = 2 supergravity with R**2 interactions. JHEP 0012, 019 (2000) (arXiv:hep-th/0009234)Google Scholar
- 14.Bates, B., Denef, F.: Exact solutions for supersymmetric stationary black hole composites (arXiv:hep-th/0304094)Google Scholar
- 15.Denef, F.: Quantum quivers and Hall/hole halos. JHEP 0210, 023 (2002) (arXiv:hep-th/0206072)Google Scholar