Conserving approximations vs Two-Particle Self-Consistent Approach

S. Allen; A. -M. S. Tremblay; Y. M. Vilk

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Conserving approximations vs Two-Particle Self-Consistent Approach

S. Allen·A. -M. S. Tremblay·Y. M. Vilk

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Abstract

The conserving approximation scheme to many-body problems was developed by Kadanoff and Baym using the functional-derivative approach. Another approach for the Hubbard model also satisfies conservation laws, but in addition it satisfies the Pauli principle and a number of sum rules. A concise formal derivation of that approach, using functional derivatives, is given in this conference paper to highlight formal analogies and differences with conserving approximations.

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S. Allen, A. -M. S. Tremblay, Y. M. Vilk. 2003-10-20. Conserving approximations vs Two-Particle Self-Consistent Approach. https://arxiv.org/abs/cond-mat/0110130

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