{ "id": "1603.03800", "version": "v1", "published": "2016-03-11T22:00:26.000Z", "updated": "2016-03-11T22:00:26.000Z", "title": "Diophantine approximation on matrices and Lie groups", "authors": [ "Menny Aka", "Emmanuel Breuillard", "Lior Rosenzweig", "Nicolas de Saxcé" ], "comment": "52 pages", "categories": [ "math.NT", "math.DS", "math.GR" ], "abstract": "We study the general problem of extremality for metric diophantine approximation on submanifolds of matrices. We formulate a criterion for extremality in terms of a certain family of algebraic obstructions and show that it is sharp. In general the almost sure diophantine exponent of a submanifold is shown to depend only on its Zariski closure, and when the latter is defined over the rational numbers, we prove that the exponent is rational and give a method to effectively compute it. This method is applied to a number of cases of interest, in particular we manage to determine the diophantine exponent of random subgroups of certain nilpotent Lie groups in terms of representation theoretic data.", "revisions": [ { "version": "v1", "updated": "2016-03-11T22:00:26.000Z" } ], "analyses": { "subjects": [ "11J83", "11J13", "11K60", "22E99", "22E25" ], "keywords": [ "representation theoretic data", "metric diophantine approximation", "nilpotent lie groups", "sure diophantine exponent", "zariski closure" ], "note": { "typesetting": "TeX", "pages": 52, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2016arXiv160303800A" } } }