Recursive Green's function approach to Feenberg perturbation theory

K. Ishida

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arXiv · 1904.00957

Recursive Green's function approach to Feenberg perturbation theory

K. Ishida

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Abstract

We propose a new procedure by using the recursive Green's functions which remove all the repetition terms from the time-independent perturbation series for finite-level quantum systems. These Green's functions are introduced as a generalization of the Brillouin-Wigner perturbation theory and the calculations of their diagonal elements can naturally give the effective propagators which are equal to the ones in the Feenberg perturbation theory.

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K. Ishida. 2019-04-01. Recursive Green's function approach to Feenberg perturbation theory. https://arxiv.org/abs/1904.00957

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