{ "id": "1205.5041", "version": "v1", "published": "2012-05-22T20:14:37.000Z", "updated": "2012-05-22T20:14:37.000Z", "title": "Simultaneous approximation to a real number and to its cube", "authors": [ "Stéphane Lozier", "Damien Roy" ], "comment": "32 pages, to appear in Acta Arithmetica", "journal": "Acta Arithmetica, vol.156 (2012), 39-73", "categories": [ "math.NT" ], "abstract": "It is known that, for each real number x such that 1,x,x^2 are linearly independent over Q, the uniform exponent of simultaneous approximation to (1,x,x^2) by rational numbers is at most (sqrt{5}-1)/2 (approximately 0.618) and that this upper bound is best possible. In this paper, we study the analogous problem for Q-linearly independent triples (1,x,x^3), and show that, for these, the uniform exponent of simultaneous approximation by rational numbers is at most 2(9+sqrt{11})/35 (approximately 0.7038). We also establish general properties of the sequence of minimal points attached to such triples that are valid for smaller values of the exponent.", "revisions": [ { "version": "v1", "updated": "2012-05-22T20:14:37.000Z" } ], "analyses": { "subjects": [ "11J13", "11J04", "11J82" ], "keywords": [ "simultaneous approximation", "real number", "uniform exponent", "rational numbers", "smaller values" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 32, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1205.5041L" } } }