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arXiv 2002.117302020-02-26hep-phhep-thnucl-th

Shear transport far from equilibrium via holography

Michael F. Wondrak, Matthias Kaminski, Marcus Bleicher

备注：: 10 pages, 4 figures
DOI：: 10.1016/j.physletb.2020.135973

英文摘要：

In heavy-ion collisions, the quark-gluon plasma is produced far from equilibrium. This regime is currently inaccessible by quantum chromodynamics (QCD) computations. We calculate shear transport and entropy far from equilibrium in a holographic model, defining a time-dependent ratio of shear viscosity to entropy density, $η/s$. Large deviations of up to 60% from its near-equilibrium value, $1/4π$, are found for realistic situations at the Large Hadron Collider. We predict the far-from-equilibrium time-dependence of $η/s$ to substantially affect the evolution of the QCD plasma and to impact the extraction of QCD properties from flow coefficients in heavy-ion collision data.

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