{
  "id": "math/9404226",
  "version": "v1",
  "published": "1994-04-15T00:00:00.000Z",
  "updated": "1994-04-15T00:00:00.000Z",
  "title": "Densities of ultraproducts of Boolean algebras",
  "authors": [
    "Sabine Koppelberg",
    "Saharon Shelah"
  ],
  "journal": "Canad. J. Math. 47 (1995), 132--145",
  "categories": [
    "math.LO",
    "math.GN"
  ],
  "abstract": "We answer three problems by J. D. Monk on cardinal invariants of Boolean algebras. Two of these are whether taking the algebraic density pi(A), resp. the topological density d(A), of a Boolean algebra A commutes with formation of ultraproducts; the third one compares the number of endomorphisms and of ideals of a Boolean algebra.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1994-04-15T00:00:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "boolean algebra",
      "ultraproducts",
      "algebraic density pi",
      "cardinal invariants",
      "topological density"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "1994math......4226K"
    }
  }
}