{
  "id": "math/9608203",
  "version": "v1",
  "published": "1996-08-06T00:00:00.000Z",
  "updated": "1996-08-06T00:00:00.000Z",
  "title": "Determinacy and Δ^1_3-degrees",
  "authors": [
    "Philip Welch"
  ],
  "categories": [
    "math.LO"
  ],
  "abstract": "Let D = { d_n } be a countable collection of Delta^1_3 degrees. Assuming that all co-analytic games on integers are determined (or equivalently that all reals have ``sharps''), we prove that either D has a Delta^1_3-minimal upper bound, or that for any n, and for every real r recursive in d_n, games in the pointclasses Delta^1_2(r) are determined. This is proven using Core Model theory.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1996-08-06T00:00:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "determinacy",
      "core model theory",
      "upper bound",
      "co-analytic games",
      "countable collection"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "1996math......8203W"
    }
  }
}