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arXiv · 1404.3224

Gray-body factor and infrared divergences in 1D BEC acoustic black holes

Paul R. Anderson·Roberto Balbinot·Alessandro Fabbri·Renaud Parentani
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Abstract

It is shown that the gray-body factor for a one-dimensional elongated Bose-Einstein condensate (BEC) acoustic black hole with one horizon does not vanish in the low-frequency ($ω\to 0$) limit. This implies that the analog Hawking radiation is dominated by the emission of an infinite number ($\frac{1}ω$) of soft phonons in contrast with the case of a Schwarzschild black hole where the gray-body factor vanishes as $ω\to 0$ and the spectrum is not dominated by low-energy particles. The infrared behaviors of certain correlation functions are also discussed.

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Paul R. Anderson, Roberto Balbinot, Alessandro Fabbri, Renaud Parentani. 2015-01-08. Gray-body factor and infrared divergences in 1D BEC acoustic black holes. https://doi.org/10.1103/physrevd.90.104044

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