{
  "annotation_id": "8dd7833f-efa6-4652-91c2-7c025ef82440",
  "date_created": "2026-03-02T18:02:19.901000Z",
  "date_modified": "2026-03-02T18:02:19.901000Z",
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  "private": false,
  "record": {
    "abstract": "We address the problem of measuring the relative angle between two \"quantum\naxes\" made out of N1 and N2 spins. Closed forms of our fidelity-like figure of\nmerit are obtained for an arbitrary number of parallel spins. The asymptotic\nregimes of large N1 and/or N2 are discussed in detail. The extension of the\nconcept \"quantum axis\" to more general situations is addressed. We give optimal\nstrategies when the first quantum axis is made out of parallel spins whereas\nthe second is a general state made out of two spins.",
    "arxiv_id": "quant-ph/0508187",
    "authors": [
      "E. Bagan",
      "S. Iblisdir",
      "R. Munoz-Tapia"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.73.022341",
    "journal_ref": "Phys. Rev. A 73, 022341 (2006)",
    "title": "Relative states, quantum axes and quantum references",
    "url": "https://arxiv.org/abs/quant-ph/0508187"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "d5c0d723-71c2-4d0b-ac22-01dda3cbfdcc",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}