{ "id": "1710.05228", "version": "v1", "published": "2017-10-14T19:53:44.000Z", "updated": "2017-10-14T19:53:44.000Z", "title": "Torsion subgroups of rational elliptic curves over the compositum of all extensions of generalized $D_4$-type", "authors": [ "Harris B. Daniels" ], "categories": [ "math.NT" ], "abstract": "Let $E/\\mathbb{Q}$ be an elliptic curve and let $\\mathbb{Q}(D_4^\\infty)$ be the compositum of all extensions of $\\mathbb{Q}$ whose Galois closure has Galois group isomorphic to a subdirect product of a finite number of transitive subgroups of $D_4$. In this article we prove that the torsion subgroup of $E(\\mathbb{Q}(D_4^\\infty))$ is finite and determine the 24 possibility for its structure. We also give a complete classification of the elliptic curves that have each possible torsion structure in terms of their $j$-invariants.", "revisions": [ { "version": "v1", "updated": "2017-10-14T19:53:44.000Z" } ], "analyses": { "subjects": [ "11G05", "11R21", "12F10", "14H52" ], "keywords": [ "rational elliptic curves", "torsion subgroup", "extensions", "compositum", "galois group isomorphic" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }