1211.0209 (M. Bonitz et al.)

Nonequilibrium Green's function approach to the pair distribution
function of quantum many-body systems out of equilibrium    [PDF]

M. Bonitz, S. Hermanns, K. Kobusch, K. Balzer

The pair distribution function (PDF) is a key quantity for the analysis of correlation effects of a quantum system both in equilibrium and far from equilibrium. We derive an expression for the PDF in terms of the single-particle Green's functions---the solutions of the Keldysh/Kadanoff-Baym equations in the two-time plane---for a one- or two-component system. The result includes initial correlations and generalizes previous density matrix expressions from single-time quantum kinetic theory. Explicit expressions for the PDF are obtained in second Born approximation.

View original: http://arxiv.org/abs/1211.0209