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arXiv · 1307.0476

Shear and bulk viscosities of a photon gas at low temperature

Antonio Dobado·Felipe J. Llanes-Estrada·Juan M. Torres-Rincon
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Abstract

We explore the viscosities of a photon gas by means of the Euler-Heisenberg effective theory and quantum electrodynamics at zero electron chemical potential. We find parametric estimates that show a very large shear viscosity and an extremely small bulk viscosity (reflecting the very weak coupling simultaneously with a very approximate dilatation invariance). The system is of some interest because it exemplifies very neatly the influence of the breaking of scale invariance on the bulk viscosity.

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Antonio Dobado, Felipe J. Llanes-Estrada, Juan M. Torres-Rincon. 2013-09-18. Shear and bulk viscosities of a photon gas at low temperature. https://doi.org/10.1103/physrevd.88.053006

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