{
  "id": "1206.0231",
  "version": "v2",
  "published": "2012-06-01T15:47:30.000Z",
  "updated": "2012-07-25T18:41:10.000Z",
  "title": "The problem with the geometric discord",
  "authors": [
    "Marco Piani"
  ],
  "comment": "5 pages. Changes in ver 2: typos corrected, added short proof of monotonicity of standard quantum discord under one-side action. This note is meant to stimulate discussion in the community: comments are welcome",
  "doi": "10.1103/PhysRevA.86.034101",
  "categories": [
    "quant-ph"
  ],
  "abstract": "We argue that the geometric discord introduced in [B. Dakic, V. Vedral, and C. Brukner, Phys. Rev. Lett. 105, 190502 (2010)] is not a good measure for the quantumness of correlations, as it can increase even under trivial local reversible operations of the party whose classicality/non-classicality is not tested. On the other hand it is known that the standard, mutual-information based discord does not suffer this problem; a simplified proof of such a fact is given.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2012-07-25T18:41:10.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "03.65.Ud",
      "03.65.Ta",
      "03.65.Aa"
    ],
    "keywords": [
      "geometric discord",
      "trivial local reversible operations",
      "quantumness",
      "correlations",
      "classicality/non-classicality"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review A",
      "year": 2012,
      "month": "Sep",
      "volume": 86,
      "number": 3,
      "pages": "034101"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 5,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2012PhRvA..86c4101P"
    }
  }
}