{
  "annotation_id": "7a3d93c1-3e2a-41e1-8fec-156a191fcb56",
  "date_created": "2026-03-02T18:02:44.974000Z",
  "date_modified": "2026-03-02T18:02:44.974000Z",
  "file_hash": "6c4ca2740c0be5e76b9d60604803a5536884ba2e427ad4b25bdccda623609ccb",
  "private": false,
  "record": {
    "abstract": "The optimal and minimal measuring strategy is obtained for a two-state system\nprepared in a mixed state with a probability given by any isotropic a priori\ndistribution. We explicitly construct the specific optimal and minimal\ngeneralized measurements, which turn out to be independent of the a priori\nprobability distribution, obtaining the best guesses for the unknown state as\nwell as a closed expression for the maximal mean averaged fidelity. We do this\nfor up to three copies of the unknown state in a way which leads to the\ngeneralization to any number of copies, which we then present and prove.",
    "arxiv_id": "quant-ph/9812068",
    "authors": [
      "G. Vidal",
      "J. I. Latorre",
      "P. Pascual",
      "R. Tarrach"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.60.126",
    "journal_ref": "Phys.Rev. A60 (1999) 126",
    "title": "Optimal minimal measurements of mixed states",
    "url": "https://arxiv.org/abs/quant-ph/9812068"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "43bf4272-9a83-4002-a53c-58c360ccf482",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}