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arXiv · 2004.05195

Non-equilibrium attractor in high-temperature QCD plasmas

Dekrayat Almaalol·Aleksi Kurkela·Michael Strickland
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Abstract

We establish the existence of a far-from-equilibrium attractor in weakly-coupled gauge theory undergoing one-dimensional Bjorken expansion. We demonstrate that the resulting far-from-equilibrium evolution is insensitive to certain features of the initial condition, including both the initial momentum-space anisotropy and initial occupancy. We find that this insensitivity extends beyond the energy-momentum tensor to the detailed form of the one-particle distribution function. Based on our results, we assess different procedures for reconstructing the full one-particle distribution function from the energy-momentum tensor along the attractor and discuss implications for the freeze-out procedure used in the phenomenological analysis of ultra-relativistic nuclear collisions.

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Dekrayat Almaalol, Aleksi Kurkela, Michael Strickland. 2020-04-10. Non-equilibrium attractor in high-temperature QCD plasmas. https://doi.org/10.1103/physrevlett.125.122302

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