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arXiv · 2208.00744

Far-from-equilibrium attractor in non-conformal plasmas

Sunil Jaiswal·Subrata Pal·Chandrodoy Chattopadhyay·Lipei Du·Ulrich Heinz
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Abstract

We study the far-off-equilibrium dynamics of a Bjorken expanding non-conformal system within kinetic theory and hydrodynamics. We show that, in contrast to the conformal case, neither shear nor bulk viscous pressure relax quickly to a non-equilibrium attractor. In kinetic theory an early-time, far-from-equilibrium attractor exists for the scaled longitudinal pressure, driven by the rapid longitudinal expansion of the medium. Second-order dissipative hydrodynamics fails to accurately describe this attractor, but a modified anisotropic hydrodynamic formulation reproduces it and provides excellent agreement with kinetic theory.

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Sunil Jaiswal, Subrata Pal, Chandrodoy Chattopadhyay, Lipei Du, Ulrich Heinz. 2022-08-01. Far-from-equilibrium attractor in non-conformal plasmas. https://arxiv.org/abs/2208.00744

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