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Integrability of the pairing hamiltonian

M. C. Cambiaggio·A. M. F. Rivas·M. Saraceno
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Abstract

We show that a many-body Hamiltonian that corresponds to a system of fermions interacting through a pairing force is an integrable problem, i.e. it has as many constants of the motion as degrees of freedom. At the classical level this implies that the Time-dependent Hartree-Fock- Bogoliubov dynamics is integrable and at the quantum level that there are conserved operators of two-body character which reduce to the number operators when the pairing strength vanishes. We display these operators explicitly and study in detail the three-level example.

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M. C. Cambiaggio, A. M. F. Rivas, M. Saraceno. 1997-08-18. Integrability of the pairing hamiltonian. https://doi.org/10.1016/s0375-9474(97)00418-1

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