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Relation between the density-matrix theory and the pairing theory

Mitsuru Tohyama·Satoshi Takahara
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Abstract

The time-dependent density-matrix theory (TDDM) gives a correlated ground state as a stationary solution of the time-dependent equations for one-body and two-body density matrices. The small amplitude limit of TDDM (STDDM) is a version of extended RPA theories which include the effects of ground state correlations. It is shown that the solutions of the Hartree-Fock Bogoliubov theory and the quasi-particle RPA satisfy the TDDM and STDDM equations, respectively, when only pairing-type correlations are taken into account in TDDM and STDDM.

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Mitsuru Tohyama, Satoshi Takahara. 2004-05-26. Relation between the density-matrix theory and the pairing theory. https://doi.org/10.1143/ptp.112.499

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