Nonequilibrium Green function approach to the pair distribution function of quantum many-body systems out of equilibrium

  title={Nonequilibrium Green function approach to the pair distribution function of quantum many-body systems out of equilibrium},
  author={Michael Bonitz and Sebastian Hermanns and Karin Kobusch and Karsten Balzer},
  journal={Journal of Physics: Conference Series},
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 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… 
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