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arXiv · 1311.4628

Shear viscosity from Kubo formalism: NJL-model study

Robert Lang·Wolfram Weise
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Abstract

A large-$N_{\rm c}$ expansion is combined with the Kubo formalism to study the shear viscosity $\eta$ of strongly interacting matter in the two-flavor NJL model. We discuss analytical and numerical approaches to $\eta$ and investigate systematically its strong dependence on the spectral width and the momentum-space cutoff. Thermal effects on the constituent quark mass from spontaneous chiral symmetry breaking are included. The ratio $\eta/s$ and its thermal dependence are derived for different parameterizations of the spectral width and for an explicit one-loop calculation including mesonic modes within the NJL model.

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Robert Lang, Wolfram Weise. 2013-11-19. Shear viscosity from Kubo formalism: NJL-model study. https://doi.org/10.1140/epja/i2014-14063-4

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