{
  "annotation_id": "2a9204b2-b9c5-425d-8444-02fca2953419",
  "date_created": "2026-03-02T18:00:50.421000Z",
  "date_modified": "2026-03-02T18:00:50.421000Z",
  "file_hash": "6528d0345f6e33999531b74d7ef5ee4a0f3836b64e7a95358c53d04d213118fc",
  "private": false,
  "record": {
    "abstract": "A rigorous method for introducing the variational principle describing\nrelativistic ideal hydrodynamic flows with all possible types of breaks\n(including shocks) is presented in the framework of an exact Clebsch type\nrepresentation of the four-velocity field as a bilinear combination of the\nscalar fields. The boundary conditions for these fields on the breaks are\nfound. We also discuss the local invariants caused by the symmetries of the\nproblem, including relabeling symmetry. In particular, the generalization of\nthe well-known nonrelativistic Ertel invariant is presented.",
    "arxiv_id": "physics/0406061",
    "authors": [
      "A. V. Kats"
    ],
    "categories": [
      "physics.flu-dyn",
      "physics.plasm-ph"
    ],
    "title": "Relativistic least action principle for discontinuous hydrodynamic   flows, Hamiltonian variables, helicity and Ertel invariant",
    "url": "https://arxiv.org/abs/physics/0406061"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "7afc3115-55ec-44c4-b577-531a3dfedc76",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}