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arXiv · 1307.3827

Non-Equilibrium 2PI Potential and Its Possible Application to Evaluation of Bulk Viscosity

Yu. B. Ivanov·D. N. Voskresensky
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Abstract

Within non-equilibrium Green's function technique on the real-time contour and the two-particle-irreducable (2PI) $Φ$-functional method, a non-equilibrium potential is introduced. It naturally generalizes the conventional thermodynamic potential with which it coincides in thermal equilibrium. Variations of the non-equilibrium potential over respective parameters result in the same quantities as those of the thermodynamic potential but in arbitrary non-equilibrium. In particular, for slightly non-equilibrium inhomogeneous configurations a variation of the non-equilibrium potential over volume is associated with the trace of the non-equilibrium stress tensor. The latter is related to the bulk viscosity. This provides a novel way for evaluation of the bulk viscosity.

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Yu. B. Ivanov, D. N. Voskresensky. 2013-07-18. Non-Equilibrium 2PI Potential and Its Possible Application to Evaluation of Bulk Viscosity. https://doi.org/10.1134/s1063778814080080

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