{
  "id": "quant-ph/0409207",
  "version": "v3",
  "published": "2004-09-29T11:04:40.000Z",
  "updated": "2004-11-25T12:55:31.000Z",
  "title": "Classical feedback for quantum channels",
  "authors": [
    "Andrew Skeen"
  ],
  "comment": "replaced incorrect definition of directed information and resulting minor changes to proofs",
  "categories": [
    "quant-ph"
  ],
  "abstract": "We investigate whether the use of a noiseless, classical feedback channel will increase the capacity of a quantum discrete memoryless channel to transmit classical information. This problem has been previously analyzed by Bowen and Nagarajan for the case of protocols restricted to product input states. They showed that feedback did not increase the information capacity. In this paper we introduce a quantum analogue of classical causality and prove a capacity theorem (in regularized form) for the transmission of classical information.",
  "revisions": [
    {
      "version": "v3",
      "updated": "2004-11-25T12:55:31.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quantum channels",
      "product input states",
      "quantum discrete memoryless channel",
      "capacity theorem",
      "transmit classical information"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2004quant.ph..9207S"
    }
  }
}