{
  "id": "math/9201245",
  "version": "v1",
  "published": "1991-01-15T00:00:00.000Z",
  "updated": "1991-01-15T00:00:00.000Z",
  "title": "Viva la difference I: Nonisomorphism of ultrapowers of countable models",
  "authors": [
    "Saharon Shelah"
  ],
  "journal": "Math. Sci. Res. Inst. Publ. 26 (1992), 357--405",
  "categories": [
    "math.LO"
  ],
  "abstract": "We show that it is not provable in ZFC that any two countable elementarily equivalent structures have isomorphic ultrapowers relative to some ultrafilter on omega .",
  "revisions": [
    {
      "version": "v1",
      "updated": "1991-01-15T00:00:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "countable models",
      "difference",
      "nonisomorphism",
      "countable elementarily equivalent structures"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}