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Converting Contour-Time to Real-Time Arguments

Giancarlo Calvanese Strinati

Published Feb 6, 2026• 0 citations

Abstract

The nonequilibrium diagrammatics and the Dyson equations contain integrations over the time variables that run over a generic contour. In both cases, the time variables run first forward and then backward along the ordinary time axis. For computational purposes, it is then required to convert these time integrals into ordinary time integrals. To this end, it is first necessary to single out all possible combinations of the pair of time variables in the contour single-particle Green’s function. This is what is done in the present chapter.

DOI: 10.1017/9781009411509.014

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