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arXiv · 2006.09561

Is perturbative study of ground-state correlations valid?

Mitsuru Tohyama
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Abstract

Perturbative approaches have often been used to include the effects of ground-state correlations in extended theories of the random-phase approximation. Validity of such approaches is investigated for a solvable model where comparison with exact solutions can be made. It is pointed out that there is a case where perturbative approaches give good results in spite of the fact that interaction strength is far beyond a perturbative region.

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Mitsuru Tohyama. 2020-06-16. Is perturbative study of ground-state correlations valid?. https://arxiv.org/abs/2006.09561

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