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arXiv · 0910.0790

A note on the analogy between superfluids and cosmology

A. Naddeo·G. Scelza
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Abstract

A new analogy between superfluid systems and cosmology is here presented, which relies strongly on the following ingredient: the back-reaction of the vacuum to the quanta of sound waves. We show how the presence of thermal phonons, the excitations above the quantum vacuum for $T> 0$, enable us to deduce an hydrodynamical equation formally similar to the one obtained for a perfect fluid in a Universe obeying the Friedmann-Robertson-Walker metric.

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A. Naddeo, G. Scelza. 2009-10-07. A note on the analogy between superfluids and cosmology. https://doi.org/10.1142/s0217984910022573

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