{ "id": "2002.01638", "version": "v1", "published": "2020-02-05T04:57:12.000Z", "updated": "2020-02-05T04:57:12.000Z", "title": "Orthogonal polynomial projection error in Dunkl-Sobolev norms in the ball", "authors": [ "Gonzalo A. Benavides", "Leonardo E. Figueroa" ], "comment": "27 pages", "categories": [ "math.CA" ], "abstract": "We study approximation properties of weighted $\\mathrm{L}^2$-orthogonal projectors onto spaces of polynomials of bounded degree in the Euclidean unit ball, where the weight is of the reflection-invariant form $(1-\\lVert x \\rVert^2)^\\alpha \\prod_{i=1}^d \\lvert x_i \\rvert^{\\gamma_i}$, $\\alpha, \\gamma_1, \\dots, \\gamma_d > -1$. Said properties are measured in Dunkl-Sobolev-type norms in which the same weighted $\\mathrm{L}^2$ norm is used to control all the involved differential-difference Dunkl operators, such as those appearing in the Sturm-Liouville characterization of similarly weighted $\\mathrm{L}^2$-orthogonal polynomials, as opposed to the partial derivatives of Sobolev-type norms. The method of proof relies on spaces instead of bases of orthogonal polynomials, which greatly simplifies the exposition.", "revisions": [ { "version": "v1", "updated": "2020-02-05T04:57:12.000Z" } ], "analyses": { "subjects": [ "41A25", "41A10", "46E35", "33C52" ], "keywords": [ "orthogonal polynomial projection error", "dunkl-sobolev norms", "euclidean unit ball", "study approximation properties", "differential-difference dunkl operators" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable" } } }