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arXiv · hep-ph/9210227

Computing Spectral Densities in Finite Temperature Field Theory

Sangyong Jeon
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Abstract

Convenient Cutkosky-like diagrammatic rules for computing the spectral densities of arbitrary two-point correlation functions in finite temperature field theory are derived. The approach is based on an explicit analytic continuation of imaginary-time Feynman diagrams and avoids the complications of real-time finite temperature perturbation theory. The application of this method to the perturbative evaluation of transport coefficients is briefly discussed.

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Sangyong Jeon. 1992-10-10. Computing Spectral Densities in Finite Temperature Field Theory. https://doi.org/10.1103/physrevd.47.4586

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