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arXiv · 0906.4787

Relativistic Viscous Fluid Dynamics and Non-Equilibrium Entropy

Paul Romatschke
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Abstract

Fluid dynamics corresponds to the dynamics of a substance in the long wavelength limit. Writing down all terms in a gradient (long wavelength) expansion up to second order for a relativistic system at vanishing charge density, one obtains the most general (causal) equations of motion for a fluid in the presence of shear and bulk viscosity, as well as the structure of the non-equilibrium entropy current. Requiring positivity of the divergence of the non-equilibrium entropy current relates some of its coefficients to those entering the equations of motion. I comment on possible applications of these results for conformal and non-conformal fluids.

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Paul Romatschke. 2010-01-22. Relativistic Viscous Fluid Dynamics and Non-Equilibrium Entropy. https://doi.org/10.1088/0264-9381%2F27%2F2%2F025006

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