{ "id": "math/9208201", "version": "v1", "published": "1992-08-13T00:00:00.000Z", "updated": "1992-08-13T00:00:00.000Z", "title": "Vector-valued L_p convergence of orthogonal series and Lagrange interpolation", "authors": [ "Hermann König", "Niels J. Nielsen" ], "journal": "Forum Math. 6 (1994), 183-207", "categories": [ "math.FA" ], "abstract": "We give necessary and sufficient conditions for interpolation inequalities of the type considered by Marcinkiewicz and Zygmund to be true in the case of Banach space-valued polynomials and Jacobi weights and nodes. We also study the vector-valued expansion problem of $L_p$-functions in terms of Jacobi polynomials and consider the question of unconditional convergence. The notion of type $p$ with respect to orthonormal systems leads to some characterizations of Hilbert spaces. It is also shown that various vector-valued Jacobi means are equivalent.", "revisions": [ { "version": "v1", "updated": "1992-08-13T00:00:00.000Z" } ], "analyses": { "subjects": [ "42C15", "46E40" ], "keywords": [ "orthogonal series", "lagrange interpolation", "banach space-valued polynomials", "sufficient conditions", "jacobi weights" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "1992math......8201K" } } }