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arXiv · 0811.1202

Suppression of the shear viscosity near the critical temperature in hot QCD

Yoshimasa Hidaka·Robert D. Pisarski
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Abstract

We consider QCD near but above critical temperature Tc. The pressure, susceptibilities and the renormalized Polyakov loop -- which is an order parameter for the deconfining phase transition -- dramatically change up to temperatures a few times Tc. We refer to this region as a "semi"-QGP, where partial confinement plays important role. We show that the shear viscosity ,eta, is suppressed by two powers of the Polyakov loop. This suggests that eta/T^3 decreases markedly as QCD cools down to temperatures near Tc. We also show a ratio of the viscosity to the entropy becomes small near Tc.

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Yoshimasa Hidaka, Robert D. Pisarski. 2008-11-07. Suppression of the shear viscosity near the critical temperature in hot QCD. https://doi.org/10.1016/j.nuclphysa.2009.01.023

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