{ "id": "math/9811148", "version": "v1", "published": "1998-11-24T19:20:22.000Z", "updated": "1998-11-24T19:20:22.000Z", "title": "Every frame is a sum of three (but nottwo) orthonormal bases, and other frame representations", "authors": [ "Peter G. Casazza" ], "comment": "to appear: J. of Fourier Anal. and Appl's", "categories": [ "math.FA" ], "abstract": "We show that every frame for a Hilbert space H can be written as a (multiple of a) sum of three orthonormal bases for H. A result of N.J. Kalton is included which shows that this is best possible in that: A frame can be represented as a linear combination of two orthonormal bases if and only if it is a Riesz basis. We further show that every frame can be written as a (multiple of a) sum of two normalized tight frames or as a sum of an orthonormal basis and a Riesz basis for H. Finally, every frame can be represented as a (multiple of a) average of two orthonormal bases for a larger Hilbert space.", "revisions": [ { "version": "v1", "updated": "1998-11-24T19:20:22.000Z" } ], "analyses": { "subjects": [ "46B20", "46C05" ], "keywords": [ "orthonormal bases", "frame representations", "riesz basis", "larger hilbert space", "linear combination" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "1998math.....11148C" } } }