{
  "annotation_id": "2eaafd49-dd30-4f7f-9025-53370dbbda70",
  "date_created": "2026-03-02T18:00:49.532000Z",
  "date_modified": "2026-03-02T18:00:49.532000Z",
  "file_hash": "1d44e55bc538be8e54c6c1050da6324755a9899821cabd8b118829dbd4ac0add",
  "private": false,
  "record": {
    "abstract": "We sketch the foundations of classical electrodynamics, in particular the\ntransition that took place when Einstein, in 1915, succeeded to formulate\ngeneral relativity. In 1916 Einstein demonstrated that, with a choice of\nsuitable variables for the electromagnetic field, it is possible to put\nMaxwell\u0027s equation into a form that is covariant under general coordinate\ntransformations. This unfolded, by basic contributions of Kottler, Cartan, van\nDantzig, Schouten \u0026 Dorgelo, Toupin \u0026 Truesdell, and Post, to what one may call\n{\\em premetric classical electrodynamics.} This framework will be described\nshortly. An analysis is given of the physical dimensions involved in\nelectrodynamics and subsequently the question of units addressed. It will be\npointed out that these results are untouched by the generalization of classical\nto quantum electrodynamics (QED). We compare critically our results with those\nof {\\sl L.B. Okun} which he had presented at a recent conference.",
    "arxiv_id": "physics/0407022",
    "authors": [
      "Friedrich W. Hehl",
      "Yuri N. Obukhov"
    ],
    "categories": [
      "physics.class-ph",
      "gr-qc",
      "hep-th",
      "physics.gen-ph"
    ],
    "doi": "10.1007/s10714-005-0059-2",
    "journal_ref": "Gen.Rel.Grav.37:733-749,2005",
    "title": "Dimensions and Units in Electrodynamics",
    "url": "https://arxiv.org/abs/physics/0407022"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ca7add93-9654-4138-8d64-f17191323973",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}