5 papers · 1 filter
Extended RPA with ground-state correlations in a solvable model
S. Takahara, M. Tohyama, P. Schuck
The ground states and excited states of the Lipkin model hamiltonian are calculated using a new theoretical approach which has been derived from an extended time-dependent Hartree-…
Relation between the density-matrix theory and the pairing theory
Mitsuru Tohyama, Satoshi Takahara
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.…
Extended RPA with ground-state correlations
M. Tohyama, S. Takahara, P. Schuck
We propose a time-independent method for finding a correlated ground state of an extended time-dependent Hartree-Fock theory, known as the time-dependent density-matrix theory (TDD…
Eigenstates of the time-dependent density-matrix theory
M. Tohyama, P. Schuck
An extended time-dependent Hartree-Fock theory, known as the time-dependent density-matrix theory (TDDM), is solved as a time-independent eigenvalue problem for low-lying sta…
Spurious modes in extended RPA theories
M. Tohyama, P. Schuck
Necessary conditions that the spurious state associated with the translational motion and its double-phonon state have zero excitation energy in extended RPA (ERPA) theories which…