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arXiv · hep-th/0111029

Two-point function reduction of four-point amputated functions and transformations in $F\bar{F}$ and RA basis in a real-time finite temperature NJL model

Bang-Rong Zhou
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Abstract

Based on a general analysis of Green functions in the real-time thermal field theory, we have proven that the four-point amputated functions in a NJL model in the fermion bubble diagram approximation behave like usual two-point functions. We expound the thermal transformations of the matrix propagator for a scalar bound state in the $F\bar{F}$ basis and in the $RA$ basis. The resulting physical causal, advanced and retarded propagator are respectively identical to corresponding ones derived in the imaginary-time formalism and this shows once again complete equivalence of the two formalisms of thermal field theory on the discussed problem in the NJL model.

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Bang-Rong Zhou. 2002-04-19. Two-point function reduction of four-point amputated functions and transformations in $F\bar{F}$ and RA basis in a real-time finite temperature NJL model. https://doi.org/10.1088/0253-6102%2F37%2F6%2F685

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