Testing viscous and anisotropic hydrodynamics in an exactly solvable case

• DOI: 10.1103/physrevc.88.024903
• Publication Date: 2013-08-08T12:47:52Z
• Authors: Wojciech Florkowski; Radoslaw Ryblewski; Michael Strickland
• Keywords: Nuclear Theory (nucl-th); High Energy Physics - Phenomenology; High Energy Physics - Phenomenology (hep-ph); Nuclear Theory; 0103 physical sciences; FOS: Physical sciences; 01 natural sciences

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.<br/>18 pages, 13 figures; v2 - published version<br/>