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arXiv · hep-ph/9910367

Nonperturbative calculation of the shear viscosity in hot phi**4 theory in real time

Enke Wang·Ulrich Heinz
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Abstract

Starting from the Kubo formula we calculate the shear viscosity in hot phi**4 theory nonperturbatively by resumming ladders with a real-time version of the Bethe-Salpeter equation at finite temperature. In the weak coupling limit, the generalized Fluctuation-Dissipation Theorem is shown to decouple the Bethe-Salpeter equations for the different real-time components of the 4-point function. The resulting scalar integral equation is identical with the one obtained by Jeon using diagrammatic ``cutting rules'' in the Imaginary Time Formalism.

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Enke Wang, Ulrich Heinz. 1999-11-10. Nonperturbative calculation of the shear viscosity in hot phi**4 theory in real time. https://doi.org/10.1016/s0370-2693(99)01324-6

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