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arXiv · 0710.5719

Shear Viscosity in a Gluon Gas

Zhe Xu·Carsten Greiner
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Abstract

The relation of the shear viscosity coefficient to the recently introduced transport rate is derived within relativistic kinetic theory. We calculate the shear viscosity over entropy ratio η/s for a gluon gas, which involves elastic gg-> gg perturbative QCD (PQCD) scatterings as well as inelastic gg<->ggg PQCD bremsstrahlung. For α_s=0.3 we find η/s=0.13 and for α_s=0.6, η/s=0.076. The small η/s values, which suggest strongly coupled systems, are due to the gluon bremsstrahlung incorporated.

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Zhe Xu, Carsten Greiner. 2008-05-27. Shear Viscosity in a Gluon Gas. https://doi.org/10.1103/physrevlett.100.172301

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