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Equal-time hierarchies for transport descriptions of fermionic fields

R. A. Ionescu·H. H. Wolter
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Abstract

A transport theory which is not restricted to the gradient and quasi-particle approximations is presented which is formulated in terms of the energy moments, or equivalently the equal-time derivatives of the one-particle Green functions. A set of infinite hierarchies of kinetic and constraint equations for equal-time quantities for the spectral and the kinetic part of the one-particle Green function are derived. The hierarchies for the spectral function truncate automatically as in the mean field approximation. The possibility of a systematic truncation of the hierarchies for the kinetic part is discussed. The effects the quantum corrections are illustrated in a simple one-dimensional model.

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R. A. Ionescu, H. H. Wolter. 2002-05-22. Equal-time hierarchies for transport descriptions of fermionic fields. https://arxiv.org/abs/nucl-th/0009022

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