{
  "annotation_id": "84ad51a4-a657-4a4e-b31a-23a8b940410e",
  "date_created": "2026-03-02T18:02:10.392000Z",
  "date_modified": "2026-03-02T18:02:10.392000Z",
  "file_hash": "1ded42a8e15d6806483871fb12a1ffb2e8934b326a95af89651b6f65aade7040",
  "private": false,
  "record": {
    "abstract": "The generalized Dirac equation of the second order, describing particles with\nspin 1/2 and two mass states, is analyzed. The projection operators extracting\nstates with definite energy and spin projections are obtained. The first order\ngeneralized Dirac equation in the 20-dimensional matrix form and the\nrelativistically invariant bilinear form are derived. We obtain the canonical\nenergy-momentum tensor and density of the electromagnetic current expressed\nthrough the 20-component wave function. Minimal and non-minimal electromagnetic\ninteractions of fermions are considered, and the quantum-mechanical Hamiltonian\nis found. It is shown that there are only causal propagations of waves in the\napproach considered.",
    "arxiv_id": "quant-ph/0408056",
    "authors": [
      "S. I. Kruglov"
    ],
    "categories": [
      "quant-ph",
      "hep-ph",
      "hep-th"
    ],
    "journal_ref": "AnnalesFond.Broglie29:1005-1016,2004; Erratum-ibid.31:489,2006",
    "title": "On the Generalized Dirac Equation for Fermions with Two Mass States",
    "url": "https://arxiv.org/abs/quant-ph/0408056"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "a8e22bef-2bc0-4a8a-916b-fdf5a59ff93c",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}