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arXiv · 1904.06780

Truncation scheme of time-dependent density-matrix approach III

Mitsuru Tohyama·Peter Schuck
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Abstract

The time-dependent density-matrix theory (TDDM) where the Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy for reduced density matrices is truncated by approximating a three-body density matrix with one-body and two-body density matrices is applied to the Lipkin model. It is shown that in the large $N$ limit the ground state in TDDM approaches the exact solution. Various truncation schemes for the three-body density matrix are also tested for an extended three-level Lipkin model.

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Mitsuru Tohyama, Peter Schuck. 2019-04-14. Truncation scheme of time-dependent density-matrix approach III. https://doi.org/10.1140/epja%2Fi2019-12746-x

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