{
  "annotation_id": "1c35fd61-b1be-4668-bb55-0b5e527d3929",
  "date_created": "2026-03-02T18:01:10.322000Z",
  "date_modified": "2026-03-02T18:01:10.322000Z",
  "file_hash": "78e838eeef743f3e2418268b8ed083fcfe9012e6e149fc6315dad7d6c8a330d0",
  "private": false,
  "record": {
    "abstract": "The concept of elementary particle rests on the idea that it is a physical\nsystem with no excited states, so that all possible states of the particle are\njust kinematical modifications of any one of them. In this way instead of\ndescribing the particle attributes it amounts to describe the collection of\nconsecutive inertial observers who describe the particle in the same\nkinematical state. The kinematical state space of an elementary particle is a\nhomogeneous space of the kinematical group.By considering the largest\nhomogeneous spaces of both, Galilei and Poincare groups, it is shown how the\nspin structure is related to the different degrees of freedom. Finally, the\nspacetime symmetry group of a relativistic particle which satisfies Dirac\u0027s\nequation when quantized, is enlarged to take into account additional symmetries\nlike spacetime dilations and local rotations. An interaction Lagrangian\ninvariant under this enlarged group is proposed and the compound system of two\nDirac particles is analyzed.",
    "arxiv_id": "physics/0608089",
    "authors": [
      "Martin Rivas"
    ],
    "categories": [
      "physics.gen-ph"
    ],
    "journal_ref": "Czech.J.Phys.56:F9-F24,2006",
    "title": "Kinematical theory of spinning particles: The interaction Lagrangian for   two spin 1/2 Dirac particles",
    "url": "https://arxiv.org/abs/physics/0608089"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ecdf3bb8-065e-4a0d-a270-fe675cfb6545",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}