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Why Self-Consistent Diagrammatic Perturbation Theory is `just' Perturbation Theory

Girish S. Setlur
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Abstract

In this short write-up we argue that self-consistent diagrammatic perturbation theory(i.e. Feynman diagrams) for the one-particle Green function is unable to capture some important qualitative features no matter how self-consistently the Green functions are obtained. This write-up is intended to highlight the short-comings of perturbation theory and also tout the advantages of the sea-boson technique(hep-th/9706006).

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Girish S. Setlur. 1999-08-19. Why Self-Consistent Diagrammatic Perturbation Theory is `just' Perturbation Theory. https://arxiv.org/abs/cond-mat/9908269

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