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arXiv · 1308.4960

Gluon spectral functions and transport coefficients in Yang--Mills theory

Michael Haas·Leonard Fister·Jan M. Pawlowski
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Abstract

We compute non-perturbative gluon spectral functions at finite temperature in quenched QCD with the maximum entropy method. We also provide a closed loop equation for the spectral function of the energy-momentum tensor in terms of the gluon spectral function. This setup is then used for computing the shear viscosity over entropy ratio $η/s$ in a temperature range from about $0.4\, T_c$ to $4.5\, T_c$. The ratio $η/s$ has a minimum at about $1.25\, T_c$ with the value of about 0.115. We also discuss extensions of the present results to QCD.

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Michael Haas, Leonard Fister, Jan M. Pawlowski. 2013-08-22. Gluon spectral functions and transport coefficients in Yang--Mills theory. https://doi.org/10.1103/physrevd.90.091501

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