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arXiv · 2108.03080

Lighthill equation for quantum liquids

C. Dedes
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Abstract

A quantum version of the Lighthill equation that originated in the field of theoretical aeroacoustics is derived for the probability density of a superfluid starting from the time-dependent Gross-Pitaevskii equation. It involves a second-order time derivative and should be supplemented by two-time boundary conditions. Its physical implications are discussed in relation to the quantum equilibrium hypothesis and the general applicability of Born's rule.

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C. Dedes. 2021-08-05. Lighthill equation for quantum liquids. https://arxiv.org/abs/2108.03080

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