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arXiv · 1802.03267

Analog gravity in nonisentropic fluids

Neven Bilić·Hrvoje Nikolić
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Abstract

The analog acoustic metric has been originally derived for adiabatic acoustic perturbations propagating in an isentropic irrotational ideal fluid. In the framework of a Lagrangian hydrodynamic description we demonstrate that under certain conditions the usual acoustic metric can be derived for nonisentropic fluids. In a special case when the pressure takes a special form and the nonadiabatic perturbations are neglected the adiabatic acoustic perturbations corresponding to massless phonons propagate in an analog metric of the usual type.

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Neven Bilić, Hrvoje Nikolić. 2018-02-09. Analog gravity in nonisentropic fluids. https://arxiv.org/abs/1802.03267

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