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Diagonalization of full finite temperature Green's function by quasi-particles

P. A. Henning·H. Umezawa
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Abstract

For thermal systems, standard perturbation theory breaks down because of the absence of stable, observable asymptotic states. We show, how the introduction of {\it statistical} quasi-particles (stable, but not observable) gives rise to a consistent description. Statistical and spectral information can be cleanly separated also for interacting systems.

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P. A. Henning, H. Umezawa. 1993-04-08. Diagonalization of full finite temperature Green's function by quasi-particles. https://doi.org/10.1016/0370-2693(93)91421-i

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