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Black holes have no short hair

Darío Núñez·Hernando Quevedo·Daniel Sudarsky
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Abstract

We show that in all theories in which black hole hair has been discovered, the region with non-trivial structure of the non-linear matter fields must extend beyond 3/2 the horizon radius, independently of all other parameters present in the theory. We argue that this is a universal lower bound that applies in every theory where hair is present. This {\it no short hair conjecture} is then put forward as a more modest alternative to the original {\it no hair conjecture}, the validity of which now seems doubtful.

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Darío Núñez, Hernando Quevedo, Daniel Sudarsky. 1996-01-12. Black holes have no short hair. https://doi.org/10.1103/physrevlett.76.571

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