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arXiv · 1305.7234

Testing viscous and anisotropic hydrodynamics in an exactly solvable case

Wojciech Florkowski·Radoslaw Ryblewski·Michael Strickland
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Abstract

We exactly solve the one-dimensional boost-invariant Boltzmann equation in the relaxation time approximation for arbitrary shear viscosity. The results are compared with the predictions of viscous and anisotropic hydrodynamics. Studying different non-equilibrium cases and comparing the exact kinetic-theory results to the second-order viscous hydrodynamics results we find that recent formulations of second-order viscous hydrodynamics agree better with the exact solution than the standard Israel-Stewart approach. Additionally, we find that, given the appropriate connection between the kinetic and anisotropic hydrodynamics relaxation times, anisotropic hydrodynamics provides a very good approximation to the exact relaxation time approximation solution.

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Wojciech Florkowski, Radoslaw Ryblewski, Michael Strickland. 2013-08-07. Testing viscous and anisotropic hydrodynamics in an exactly solvable case. https://doi.org/10.1103/physrevc.88.024903

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