{
  "annotation_id": "6009e120-a4e1-4a61-b04f-18e458d39963",
  "date_created": "2026-03-02T18:02:07.032000Z",
  "date_modified": "2026-03-02T18:02:07.032000Z",
  "file_hash": "65a3bd8caec3a3affed0e4c02c1e1532645378765bf2d3ca1a7f501fb74a0a47",
  "private": false,
  "record": {
    "abstract": "The problem of the estimation of multiple phases (or of commuting unitaries)\nis considered. This is a sub-model of the estimation of a completely unknown\nunitary operation where it has been shown in recent works that there are\nconsiderable improvements by using entangled input states and entangled\nmeasurements. Here it is shown that when estimating commuting unitaries, there\nis practically no advantage in using entangled input states or entangled\nmeasurements.",
    "arxiv_id": "quant-ph/0403190",
    "authors": [
      "Manuel A. Ballester"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.70.032310",
    "journal_ref": "Phys. Rev. A 70, 032310 (2004)",
    "title": "Entanglement is not very useful for estimating multiple phases",
    "url": "https://arxiv.org/abs/quant-ph/0403190"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "1c5a9db5-fc2d-475f-aeef-bf0f11f34347",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}