{
  "annotation_id": "0cd92081-fe6c-45a9-a0e8-2c8379a80e94",
  "date_created": "2026-03-02T18:02:40.511000Z",
  "date_modified": "2026-03-02T18:02:40.511000Z",
  "file_hash": "5040b499af8640e635e70a6cd1953ffdb70b3a3ea465c80b98855979c25be945",
  "private": false,
  "record": {
    "abstract": "It is a well-known fact that all the statistical predictions of quantum\nmechanics on the state of any physical system represented by a two-dimensional\nHilbert space can always be duplicated by a noncontextual hidden-variables\nmodel. In this paper, I show that, in some cases, when we consider an\nadditional independent (unentangled) two-dimensional system, the quantum\ndescription of the resulting composite system cannot be reproduced using\nnoncontextual hidden variables. In particular, a no-hidden-variables proof is\npresented for two individual spin-1/2 particles preselected in an uncorrelated\nstate AB and postselected in another uncorrelated state aB, B being the same\nstate for the second particle in both preselection and postselection.",
    "arxiv_id": "quant-ph/9706016",
    "authors": [
      "Adan Cabello"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.55.4109",
    "journal_ref": "Phys.Rev. A55 (1997) 4109-4111",
    "title": "No-hidden-variables proof for two spin-1/2 particles preselected and   postselected in unentangled states",
    "url": "https://arxiv.org/abs/quant-ph/9706016"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "83c66270-9a4b-436f-be7b-36618abb939a",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}