Many-body theory of degenerate systems: A simple example

Christian Brouder

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arXiv · cond-mat/0312158

Many-body theory of degenerate systems: A simple example

Christian Brouder

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Abstract

The hierarchy of Green functions for (quasi)degenerate systems, presented in cond-mat/0308058, is calculated in detail for the case of a system with closed shells plus a single electron in a two-fold degenerate level. The complete hierarchy is derived explicitly, in terms of Green functions and of Feynman diagrams.

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Christian Brouder. 2003-12-05. Many-body theory of degenerate systems: A simple example. https://arxiv.org/abs/cond-mat/0312158

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