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Observer dependence for the phonon content of the sound field living on the effective curved space-time background of a Bose-Einstein condensate

Petr O. Fedichev·Uwe R. Fischer
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Abstract

We demonstrate that the ambiguity of the particle content for quantum fields in a generally curved space-time can be experimentally investigated in an ultracold gas of atoms forming a Bose-Einstein condensate. We explicitly evaluate the response of a suitable condensed matter detector, an ``Atomic Quantum Dot,'' which can be tuned to measure time intervals associated to different effective acoustic space-times. It is found that the detector response related to laboratory, ``adiabatic,'' and de Sitter time intervals is finite in time and nonstationary, vanishing, and thermal, respectively.

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Petr O. Fedichev, Uwe R. Fischer. 2004-03-31. Observer dependence for the phonon content of the sound field living on the effective curved space-time background of a Bose-Einstein condensate. https://doi.org/10.1103/physrevd.69.064021

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