{ "id": "1005.4206", "version": "v2", "published": "2010-05-23T14:17:52.000Z", "updated": "2010-05-27T12:15:28.000Z", "title": "The Tate-Shafarevich group for elliptic curves with complex multiplication II", "authors": [ "J. Coates", "Z. Liang", "R. Sujatha" ], "comment": "24 pages", "categories": [ "math.NT" ], "abstract": "Let E be an elliptic curve over Q with complex multiplication. The aim of the present paper is to strengthen the theoretical and numerical results of \\cite{CZS}. For each prime p, let t_{E/Q, p} denote the Z_p-corank of the p-primary subgroup of the Tate-Shafarevich group of E/Q. For each \\epsilon 0, we prove that t_{E/Q, p} is bounded above by (1/2+\\epsilon)p for all sufficiently large good ordinary primes p. We also do numerical calculations on one such E of rank 3, and 5 such E of rank 2, showing in all cases that t_{E/Q, p} = 0 for all good ordinary primes p < 30,000. In fact, we show that, with the possible exception of one good ordinary prime in this range for just one of the curves of rank 2, the p-primary subgroup of the Tate-Shafarevich group of the curve is zero (always supposing p is a good ordinary prime).", "revisions": [ { "version": "v2", "updated": "2010-05-27T12:15:28.000Z" } ], "analyses": { "subjects": [ "11G05", "11G15" ], "keywords": [ "tate-shafarevich group", "elliptic curve", "complex multiplication", "ordinary prime", "p-primary subgroup" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1005.4206C" } } }