{
  "annotation_id": "2afbc721-6843-4b7e-9d25-7f11563034d4",
  "date_created": "2026-03-02T18:01:42.313000Z",
  "date_modified": "2026-03-02T18:01:42.313000Z",
  "file_hash": "2fe3a323075e96d3abe81e94138eaeb8504d111abcce930e6dd4be833863d2b0",
  "private": false,
  "record": {
    "abstract": "Wootters [Phys. Rev. Lett. 80, 2245 (1998)] has given an explicit formula for\nthe entanglement of formation of two qubits in terms of what he calls the\nconcurrence of the joint density operator. Wootters\u0027s concurrence is defined\nwith the help of the superoperator that flips the spin of a qubit. We\ngeneralize the spin-flip superoperator to a \"universal inverter,\" which acts on\nquantum systems of arbitrary dimension, and we introduce the corresponding\nconcurrence for joint pure states of (D1 X D2) bipartite quantum systems. The\nuniversal inverter, which is a positive, but not completely positive\nsuperoperator, is closely related to the completely positive universal-NOT\nsuperoperator, the quantum analogue of a classical NOT gate. We present a\nphysical realization of the universal-NOT superoperator.",
    "arxiv_id": "quant-ph/0102040",
    "authors": [
      "Pranaw Rungta",
      "V. Buzek",
      "Carlton M. Caves",
      "M. Hillery",
      "G. J. Milburn"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.64.042315",
    "title": "Universal state inversion and concurrence in arbitrary dimensions",
    "url": "https://arxiv.org/abs/quant-ph/0102040"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "49eb2014-1145-4ae2-b5bc-d1d7d51b9653",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}