{
  "annotation_id": "bea68f13-f766-4446-aea8-8ffc313db521",
  "date_created": "2026-03-02T18:02:03.349000Z",
  "date_modified": "2026-03-02T18:02:03.349000Z",
  "file_hash": "6a68ff09c75127cac7ec9e97568a7e76e310823af020548d6fdb27e8b5d8b7c2",
  "private": false,
  "record": {
    "abstract": "We provide optimal measurement schemes for estimating relative parameters of\nthe quantum state of a pair of spin systems. We prove that the optimal\nmeasurements are joint measurements on the pair of systems, meaning that they\ncannot be achieved by local operations and classical communication. We also\ndemonstrate that in the limit where one of the spins becomes macroscopic, our\nresults reproduce those that are obtained by treating that spin as a classical\nreference direction.",
    "arxiv_id": "quant-ph/0310009",
    "authors": [
      "Stephen D. Bartlett",
      "Terry Rudolph",
      "Robert W. Spekkens"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.70.032321",
    "journal_ref": "Phys. Rev. A 70, 032321 (2004)",
    "title": "Optimal measurements for relative quantum information",
    "url": "https://arxiv.org/abs/quant-ph/0310009"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "c8b61ad5-44e5-4859-8be6-8f155337c40c",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}