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arXiv · 2210.06712

Far-from-equilibrium attractors with a realistic non-conformal equation of state

Mubarak Alqahtani
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Abstract

Using anisotropic hydrodynamics, we examine the existence of early-time attractors of non-conformal systems undergoing Bjorken expansion. In the case of a constant mass, we find that the evolution of the scaled longitudinal pressure is insensitive to variations of initial conditions converging onto an early-time universal curve and eventually merging with the late-time Navier-Stokes attractor (the hydrodynamic attractor). On the other hand, the bulk and the shear viscous corrections do not show an early-time attractor behavior. These results are consistent with previous studies considering a constant mass. When a realistic equation of state is included in the dynamics with a thermal mass, we demonstrate for the first time the absence of strict late-time universal attractors. However, a semi-universal feature of the evolution at very late times remains.

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Mubarak Alqahtani. 2022-10-13. Far-from-equilibrium attractors with a realistic non-conformal equation of state. https://doi.org/10.1016/j.nuclphysb.2023.116148

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