{ "id": "math/0703349", "version": "v2", "published": "2007-03-12T16:36:58.000Z", "updated": "2007-09-07T15:12:20.000Z", "title": "Equivalence of A-Approximate Continuity for Self-Adjoint Expansive Linear Maps", "authors": [ "Angel San Antolin", "Szilárd Gy. Révész" ], "categories": [ "math.CA" ], "abstract": "Let A be an expansive linear map from R^d to R^d. The notion of A-approximate continuity was recently used to give a characterization of scaling functions in a multiresolution analysis (MRA). The definition of A-approximate continuity at a point x - or, equivalently, the definition of the family of sets having x as point of A-density - depend on the expansive linear map A. The aim of the present paper is to characterize those self-adjoint expansive linear maps A_1, A_2 for which the respective concepts of A_j-approximate continuity (j=1,2) coincide. These we apply to analyze the equivalence among dilation matrices for a construction of systems of MRA. In particular, we give a full description for the equivalence class of the dyadic dilation matrix among all self-adjoint expansive maps. If the so-called ``four exponentials conjecture'' of algebraic number theory holds true, then a similar full description follows even for general self-adjoint expansive linear maps, too.", "revisions": [ { "version": "v2", "updated": "2007-09-07T15:12:20.000Z" } ], "analyses": { "subjects": [ "15A04", "42C40" ], "keywords": [ "a-approximate continuity", "equivalence", "algebraic number theory holds true", "general self-adjoint expansive linear maps", "full description" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007math......3349S" } } }