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arXiv · 0705.2564

How many black holes fit on the head of a pin?

Frederik Denef·Gregory W. Moore
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Abstract

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.

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Frederik Denef, Gregory W. Moore. 2007-05-17. How many black holes fit on the head of a pin?. https://doi.org/10.1007/s10714-007-0469-4 10.1142/s0218271808012437

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