{
  "id": "1011.4145",
  "version": "v1",
  "published": "2010-11-18T07:12:28.000Z",
  "updated": "2010-11-18T07:12:28.000Z",
  "title": "A short and elementary proof of Hanner's theorem",
  "authors": [
    "Aasa Feragen"
  ],
  "comment": "2 pages",
  "categories": [
    "math.GN",
    "math.GT"
  ],
  "abstract": "Hanner's theorem is a classical theorem in the theory of retracts and extensors in topological spaces, which states that a local ANE is an ANE. While Hanner's original proof of the theorem is quite simple for separable spaces, it is rather involved for the general case. We provide a proof which is not only short, but also elementary, relying only on well-known classical point-set topology.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2010-11-18T07:12:28.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "54C55",
      "55M15",
      "54C20"
    ],
    "keywords": [
      "hanners theorem",
      "elementary proof",
      "well-known classical point-set topology",
      "hanners original proof",
      "quite simple"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 2,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2010arXiv1011.4145F"
    }
  }
}