{
  "annotation_id": "f90df120-6387-417b-8eed-4b69a67a72bd",
  "date_created": "2026-03-02T18:02:44.642000Z",
  "date_modified": "2026-03-02T18:02:44.642000Z",
  "file_hash": "0a68ea7f1d3422e97575de31d94398d71143dfeda02103e784f6afe338f467e1",
  "private": false,
  "record": {
    "abstract": "Generalized Euler-Arnold-von Neumann density matrix equations can be solved\nby a binary Darboux transformation given here in a new form:\n$\\rho[1]=e^{P\\ln(\\mu/\\nu)}\\rho e^{-P\\ln(\\mu/\\nu)}$ where $P=P^2$ is explicitly\nconstructed in terms of conjugated Lax pairs, and $\\mu$, $\\nu$ are complex. As\na result spectra of $\\rho$ and $\\rho[1]$ are identical. Transformations\nallowing to shift and rescale spectrum of a solution are introduced, and a\nclass of stationary seed solutions is discussed.",
    "arxiv_id": "quant-ph/9810023",
    "authors": [
      "Maciej Kuna",
      "Marek Czachor",
      "Sergiej B. Leble"
    ],
    "categories": [
      "quant-ph",
      "nlin.SI",
      "solv-int"
    ],
    "doi": "10.1016/S0375-9601(99)00157-7",
    "journal_ref": "Phys.Lett. A255 (1999) 42-48",
    "title": "Nonlinear von Neumann-type equations: Darboux invariance and spectra",
    "url": "https://arxiv.org/abs/quant-ph/9810023"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "57dc38fa-8f49-4b6d-a076-dd6ec0bfe60f",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}