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arXiv · 1401.5231

Superfluid hydrodynamics of polytropic gases:dimensional reduction and sound velocity

Nicola Bellomo·Giovanni Mazzarella·Luca Salasnich
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Abstract

Motivated by the fact that two-component confined fermionic gases in Bardeen-Cooper-Schrieffer-Bose-Einstein condensate (BCS-BEC) crossover can be described through an hydrodynamical approach, we study these systems - both in the cigar-shaped configuration and in the disk-shaped one - by using a polytropic Lagrangian density. We start from the Popov Lagrangian density and obtain, after a dimensional reduction process, the equations that control the dynamics of such systems. By solving these equations we study the sound velocity as a function of the density by analyzing how the dimensionality affects this velocity

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Nicola Bellomo, Giovanni Mazzarella, Luca Salasnich. 2014-01-21. Superfluid hydrodynamics of polytropic gases:dimensional reduction and sound velocity. https://doi.org/10.1088/1751-8113/47/9/095201

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