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arXiv · 1906.10140

Moving black holes: energy extraction, absorption cross-section and the ring of fire

Vitor Cardoso·Rodrigo Vicente
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Abstract

We consider the interaction between a plane wave and a (counter-moving) black hole. We show that energy is transferred from the black hole to the wave, giving rise to a negative absorption cross-section. Moving black holes absorb radiation and deposit energy in external radiation. Due to this effect, a black hole hole of mass M moving at relativistic speeds in a cold medium will appear to be surrounded by a bright "ring" of diameter 3\sqrt{3}GM/c^2 and thickness GM/c^2.

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BibTeXRIS

Vitor Cardoso, Rodrigo Vicente. 2019-06-24. Moving black holes: energy extraction, absorption cross-section and the ring of fire. https://doi.org/10.1103/physrevd.100.084001

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