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arXiv · 1802.09535

QCD Shear Viscosity at (almost) NLO

Jacopo Ghiglieri·Guy D. Moore·Derek Teaney
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Abstract

We compute the shear viscosity of QCD with matter, including almost all next-to-leading order corrections -- that is, corrections suppressed by one power of $g$ relative to leading order. We argue that the still missing terms are small. The next-to-leading order corrections are large and bring $\eta/s$ down by more than a factor of 3 at physically relevant couplings. The perturbative expansion is problematic even at $T \simeq 100$ GeV. The largest next-to-leading order correction to $\eta/s$ arises from modifications to the qhat parameter, which determines the rate of transverse momentum diffusion. We also explore quark number diffusion, and shear viscosity in pure-glue QCD and in QED.

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Jacopo Ghiglieri, Guy D. Moore, Derek Teaney. 2018-02-26. QCD Shear Viscosity at (almost) NLO. https://doi.org/10.1007/jhep03(2018)179

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