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arXiv · 1308.1771

Viscous coefficients of a hot pion gas

Sourav Sarkar
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Abstract

The steps essentially involved in the evaluation of transport coefficients in linear response theory using Kubo formulas are to relate the defining {\em retarded} correlation function to the corresponding {\em time-ordered} one and to evaluate the latter in the conventional perturbation expansion. Here we evaluate the viscosities of a pion gas carrying out both the steps in the {\em real time} formulation. We also obtain the viscous coefficients by solving the relativistic transport equation in the Chapman-Enskog approximation to leading order. An in-medium $ππ$ cross-section in used in which spectral modifications are introduced in the propagator of the exchanged $ρ$.

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Sourav Sarkar. 2013-08-08. Viscous coefficients of a hot pion gas. https://doi.org/10.1155/2013%2F627137

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