{
  "annotation_id": "89403614-552c-42f6-bb08-f928d776dd2e",
  "date_created": "2026-03-02T18:02:10.048000Z",
  "date_modified": "2026-03-02T18:02:10.048000Z",
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  "record": {
    "abstract": "While a positive operator valued measure gives the probabilities in a quantum\nmeasurement, an instrument gives both the probabilities and the a posteriori\nstates. By interpreting the instrument as a quantum channel and by using the\ntypical inequalities for the quantum and classical relative entropies, many\nbounds on the classical information extracted in a quantum measurement, of the\ntype of Holevo\u0027s bound, are obtained in a unified manner.",
    "arxiv_id": "quant-ph/0409019",
    "authors": [
      "Alberto Barchielli",
      "Giancarlo Lupieri"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1134/1.2055938",
    "journal_ref": "Optics and Spectroscopy 99 (2005) 425-432",
    "title": "Instruments and channels in quantum information theory",
    "url": "https://arxiv.org/abs/quant-ph/0409019"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "8dc14934-3077-4108-8260-2a4be7e4165e",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}