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Quasi-particle creation by analogue black holes

Carlos Barcelo·Stefano Liberati·Sebastiano Sonego·Matt Visser
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Abstract

We discuss the issue of quasi-particle production by ``analogue black holes'' with particular attention to the possibility of reproducing Hawking radiation in a laboratory. By constructing simple geometric acoustic models, we obtain a somewhat unexpected result: We show that in order to obtain a stationary and Planckian emission of quasi-particles, it is not necessary to create an ergoregion in the acoustic spacetime (corresponding to a supersonic regime in the flow). It is sufficient to set up a dynamically changing flow either eventually generating an arbitrarily small sonic region v=c, but without any ergoregion, or even just asymptotically, in laboratory time, approaching a sonic regime with sufficient rapidity.

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Carlos Barcelo, Stefano Liberati, Sebastiano Sonego, Matt Visser. 2006-04-12. Quasi-particle creation by analogue black holes. https://doi.org/10.1088/0264-9381%2F23%2F17%2F014

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