https://doi.org/10.1140/epja/i2019-12746-x
Regular Article - Theoretical Physics
Truncation scheme of time-dependent density-matrix approach III
1
Kyorin University School of Medicine, 181-8611, Mitaka, Tokyo, Japan
2
Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, F-91406, Orsay Cedex, France
3
Laboratoire de Physique et de Modélisation des Milieux Condensés, CNRS et Université Joseph Fourier, 25 Av. des Martyrs, BP 166, F-38042, Grenoble Cedex 9, France
* e-mail: tohyama@ks.kyorin-u.ac.jp
Received:
30
January
2019
Accepted:
25
March
2019
Published online:
20
May
2019
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.
© Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2019
