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A Deduced Feynman Rule for Calculating Retarded and Advanced Green function in Closed Time Path Formalism

Jun Xiao·Enke Wang
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Abstract

Based on the closed time path formalism, a new Feynman rule for directly calculating the retarded and advanced Green functions is deduced. This Feynman rule is used to calculate the two-point self-energy and three-point vertex correction in $ϕ^3$ theory. The generalized fluctuation-dissipation theorem for three-point nonlinear response function is verified.

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Jun Xiao, Enke Wang. 2002-05-21. A Deduced Feynman Rule for Calculating Retarded and Advanced Green function in Closed Time Path Formalism. https://arxiv.org/abs/hep-ph/0204009

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