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American Journal of Physics

Green Functions and Perturbation Theory

William Silvert

Published Jan 1, 1972• 0 citations
Publisher

Abstract

We show a pedagogically useful way of deriving both stationary and time-dependent perturbation theory from the field-theoretical Hartree-Fock approximation. The calculation clearly shows how the contributions of real and virtual processes differ.
DOI
10.1119/1.1986452

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