{
  "annotation_id": "3103ba40-27e4-4130-bcce-fc98fa8839a2",
  "date_created": "2026-03-02T18:00:08.583000Z",
  "date_modified": "2026-03-02T18:00:08.583000Z",
  "file_hash": "5019bdf6e0d22f30bb634747847fe41232c078785c6dc36dc1e92bbe013d4279",
  "private": false,
  "record": {
    "abstract": "Various classical counterparts for the two-level pairing model in a\nmany-fermion system are presented in the Schwinger boson representation. It is\nshown that one of the key ingredients giving the classical descriptions for\nquantal system is the use of the various trial states besides the $su(2)\\otimes\nsu(2)$-coherent state, which may be natural selection for the two-level pairing\nmodel governed by the $su(2)\\otimes su(2)$-algebra. It is pointed out that the\nfictitious behavior like the sharp phase transition can be avoided by using the\nother states such as the $su(2)\\otimes su(1,1)$- and the $su(1,1)\\otimes\nsu(1,1)$-coherent states, while the sharp phase transition appears in the usual\nHartree-Fock-Bogoliubov and the quasi-particle random phase approximations in\nthe original fermion system.",
    "arxiv_id": "nucl-th/0610074",
    "authors": [
      "Y. Tsue",
      "C. Providencia",
      "J. da Providencia",
      "M. Yamamura"
    ],
    "categories": [
      "nucl-th"
    ],
    "doi": "10.1143/PTP.117.835",
    "journal_ref": "Prog.Theor.Phys.117:835-851,2007",
    "title": "Classical and Quantal Descriptions of Small Amplitude Fluctuations   Around Equilibriums in the Two-Level Pairing Model",
    "url": "https://arxiv.org/abs/nucl-th/0610074"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "1545eec8-5378-4983-88df-073bb983555e",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}