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arXiv · 0910.3613

Post-Wick theorems for symbolic manipulation of second-quantized expressions in atomic many-body perturbation theory

Andrei Derevianko
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Abstract

Manipulating expressions in many-body perturbation theory becomes unwieldily with increasing order of the perturbation theory. Here I derive a set of theorems for efficient simplification of such expressions. The derived rules are specifically designed for implementing with symbolic algebra tools. As an illustration, we count the numbers of Brueckner-Goldstone diagrams in the first several orders of many-body perturbation theory for matrix elements between two states of a mono-valent system.

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Andrei Derevianko. 2009-10-19. Post-Wick theorems for symbolic manipulation of second-quantized expressions in atomic many-body perturbation theory. https://doi.org/10.1088/0953-4075/43/7/074001

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