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arXiv · hep-ph/0609255

The ratio of viscosity to entropy density in a pion gas satisfies the KSS holographic bound

Antonio Dobado·Felipe J. Llanes-Estrada
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Abstract

We evaluate the ratio of shear viscosity to entropy density in a pion gas employing the Uehling-Uehlenbeck equation and experimental phase-shifts parameterized by means of the SU(2) Inverse Amplitude Method. We find that the ratio for this monocomponent gas stays well above the KSS 1/(4 pi) bound. We find similar results with other sets of phase shifts and conclude the bound is nowhere violated.

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Antonio Dobado, Felipe J. Llanes-Estrada. 2006-10-30. The ratio of viscosity to entropy density in a pion gas satisfies the KSS holographic bound. https://doi.org/10.1140/epjc%2Fs10052-006-0176-4

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