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arXiv · 1809.10037

Horizon hair of extremal black holes and measurements at null infinity

Yannis Angelopoulos·Stefanos Aretakis·Dejan Gajic
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Abstract

It is shown that the conserved charges on the event horizon and the Cauchy horizon associated to scalar perturbations on extremal black holes are externally measurable from null infinity. This suggests that these charges have the potential to serve as an observational signature. The proof of this result is based on obtaining precise late-time asymptotics for the radiation field of outgoing perturbations.

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Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic. 2018-09-26. Horizon hair of extremal black holes and measurements at null infinity. https://doi.org/10.1103/physrevlett.121.131102

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