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arXiv · 1711.01657

Analytical attractor and the divergence of the slow-roll expansion in relativistic hydrodynamics

Gabriel S. Denicol·Jorge Noronha
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Abstract

We find the general analytical solution of the viscous relativistic hydrodynamic equations (in the absence of bulk viscosity and chemical potential) for a Bjorken expanding fluid with a constant shear viscosity relaxation time. We analytically determine the hydrodynamic attractor of this fluid and discuss its properties. We show for the first time that the slow-roll expansion, a commonly used approach to characterize the attractor, diverges. This is shown to hold also in a conformal plasma. The gradient expansion is found to converge in an example where causality and stability are violated.

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Gabriel S. Denicol, Jorge Noronha. 2017-11-05. Analytical attractor and the divergence of the slow-roll expansion in relativistic hydrodynamics. https://doi.org/10.1103/physrevd.97.056021

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