{
  "annotation_id": "55f1fa51-d8fc-44c5-a100-efc0e070e16b",
  "date_created": "2026-03-02T18:01:00.414000Z",
  "date_modified": "2026-03-02T18:01:00.414000Z",
  "file_hash": "1119ba88b408c1ae439e91bbc532391528a878e8572c905b0bc075f0831a1f41",
  "private": false,
  "record": {
    "abstract": "We present a space-time diagram that displays in true values the space- time\ncoordinates of events associated with the apparent and actual positions of a\npoint like source moving with constant velocity. We use it in order to\nconstruct the actual shape of a moving luminous profile or to determine the\nrelationship between apparent and actual distances. We show that the simple\nfact that light propagates at finite speed has important consequences like\n\"length contraction\" or \"length dilation\" the effects being sensitive against\nthe \"approaching\" and the \"receding\" character of the source relative to an\nobserver located at the origin of the inertial reference frame",
    "arxiv_id": "physics/0509225",
    "authors": [
      "Bernhard Rothenstein",
      "Stefan Popescu",
      "George J. Spix"
    ],
    "categories": [
      "physics.gen-ph"
    ],
    "title": "Illustrating the space-time coordinates of the events associated with   the apparent and the actual position of a light source",
    "url": "https://arxiv.org/abs/physics/0509225"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "667f9110-c579-4ba7-b9e5-aea425570b41",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}