{
  "id": "1709.10503",
  "version": "v1",
  "published": "2017-09-29T17:26:28.000Z",
  "updated": "2017-09-29T17:26:28.000Z",
  "title": "Special subgroups of Bianchi groups",
  "authors": [
    "Michelle Chu"
  ],
  "comment": "14 pages",
  "categories": [
    "math.GR",
    "math.GT"
  ],
  "abstract": "We determine C-special subgroups of the Bianchi groups of index bounded above by 120 by effectivising the arguments of Agol-Long-Reid. These subgroups are congruence of level 2 or 4 and retract to the free group on two generators. As a consequence, we find a C-special 20-sheeted cover of the figure-eight knot complement. We also determine C-special congruence subgroups for a family of cocompact arithmetic Kleinian groups.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-09-29T17:26:28.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "bianchi groups",
      "cocompact arithmetic kleinian groups",
      "determine c-special congruence subgroups",
      "determine c-special subgroups",
      "figure-eight knot complement"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}