{
  "annotation_id": "01262710-800d-404a-94a2-c6a17172a733",
  "date_created": "2026-03-02T18:01:45.568000Z",
  "date_modified": "2026-03-02T18:01:45.568000Z",
  "file_hash": "016e89ae7a46a8870dc7cd4aea93741654c073692de7c686f7aa124fb885758e",
  "private": false,
  "record": {
    "abstract": "Is there any point of principle that prohibits us from doing one or more\nforms of quantum information processing? It is now well known that an unknown\nquantum state can neither be copied nor deleted perfectly. Given a set of\nstates which are not necessarily orthogonal, is it possible to compare any two\nstates from the set, given some reasonable ordering of such states? Is it\npossible to sort them in some specific order? In the context of quantum\ncomputation, it is shown here that there is no quantum circuit implementing a\nunitary transformation, for comparing and sorting an unrestricted set of\nquantum states.",
    "arxiv_id": "quant-ph/0107085",
    "authors": [
      "A. John Arul"
    ],
    "categories": [
      "quant-ph"
    ],
    "title": "Impossibility of comparing and sorting quantum states",
    "url": "https://arxiv.org/abs/quant-ph/0107085"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "ca9ae633-95f9-4179-8fa5-103f3e81897b",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}