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RPA equations and the instantaneous Bethe-Salpeter equation

J. Resag·D. Schütte
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Abstract

We give a derivation of the particle-hole RPA equations for an interacting multi-fermion system by applying the instantaneous approximation to the amputated two-fermion propagator of the system. In relativistic field theory the same approximation leads from the fermion-antifermion Bethe-Salpeter equation to the Salpeter equation. We show that RPA equations and Salpeter equation are indeed equivalent.

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J. Resag, D. Schütte. 1993-12-21. RPA equations and the instantaneous Bethe-Salpeter equation. https://arxiv.org/abs/nucl-th/9312013

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