Cambridge University Press eBooks

State-of-the-Art Numerical Methods

Giancarlo Calvanese Strinati

Published Feb 6, 2026• 0 citations

Abstract

This chapter gives a brief survey about the “time-stepping procedure” and the “predictor-corrector scheme” for solving the Kadanoff–Baym equations with two ( t and t ′) time variables. In this respect, the solutions of the Kadanoff–Baym equations for the greater and lesser Green’s functions are combined with each other in the positive quadrant of the t − t ′ plane, together with the solution of the lesser Green’s function along the time diagonal where t = t ′. The “generalized Kadanoff–Baym ansatz”, which aims at somewhat simplifying the solution of the Kadanoff–Baym equations themselves, is also introduced and derived in detail.

DOI: 10.1017/9781009411509.039

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