{
  "id": "2101.03797",
  "version": "v1",
  "published": "2021-01-11T10:21:09.000Z",
  "updated": "2021-01-11T10:21:09.000Z",
  "title": "Models for quotients of modular curves",
  "authors": [
    "Josha Box"
  ],
  "categories": [
    "math.NT"
  ],
  "abstract": "We describe an algorithm for computing a $\\Q$-rational model for the quotient of a modular curve by an automorphism group, under mild assumptions on the curve and the automorphisms, by determining $q$-expansions for a basis of the corresponding space of cusp forms. We also give a moduli interpretation for general morphisms between modular curves.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-01-11T10:21:09.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "11F11",
      "11G18"
    ],
    "keywords": [
      "modular curve",
      "general morphisms",
      "rational model",
      "automorphism group",
      "mild assumptions"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}