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arXiv · 2112.14042

Causal first-order hydrodynamics from kinetic theory and holography

Raphael E. Hoult·Pavel Kovtun
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Abstract

We show how causal relativistic Navier-Stokes equations arise from the relativistic Boltzmann equation: the causality is preserved via a judicious choice of the zero modes of the collision operator. A completely analogous procedure may be used to extract causal hydrodynamics from the fluid-gravity correspondence: again, causality of the hydrodynamic equations is preserved by a suitable choice of zero modes of the corresponding differential operators in the bulk. We give examples of zero modes which give rise to causal hydrodynamic equations for non-conformal fluids with a conserved U(1) global symmetry current.

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Raphael E. Hoult, Pavel Kovtun. 2021-12-28. Causal first-order hydrodynamics from kinetic theory and holography. https://doi.org/10.1103/physrevd.106.066023

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