{ "id": "0809.4054", "version": "v1", "published": "2008-09-23T23:46:14.000Z", "updated": "2008-09-23T23:46:14.000Z", "title": "A sharp inequality for the Strichartz norm", "authors": [ "Emanuel Carneiro" ], "comment": "15 pages. Submitted", "journal": "International Mathematics Research Notices, p. 3127-3145, 2009", "doi": "10.1093/imrn/rnp045", "categories": [ "math.AP", "math.CA" ], "abstract": "Let $u:\\R \\times \\R^n \\to \\C$ be the solution of the linear Schr\\\"odinger equation $iu_t + \\Delta u =0$ with initial data $u(0,x) = f(x)$. In the first part of this paper we obtain a sharp inequality for the Strichartz norm $\\|u(t,x)\\|_{L^{2k}_tL^{2k}_x(\\R \\times\\R^n)}$, where $k\\in \\Z$, $k \\geq 2$ and $(n,k) \\neq (1,2)$, that admits only Gaussian maximizers. As corollaries we obtain sharp forms of the classical Strichartz inequalities in low dimensions (works of Foschi and Hundertmark - Zharnitsky) and also sharp forms of some Sobolev-Strichartz inequalities. In the second part of the paper we express Foschi's sharp inequalities for the Schr\\\"odinger and wave equations in the broader setting of sharp restriction/extension estimates for the paraboloid and the cone.", "revisions": [ { "version": "v1", "updated": "2008-09-23T23:46:14.000Z" } ], "analyses": { "subjects": [ "41A44", "42A05" ], "keywords": [ "sharp inequality", "strichartz norm", "sharp forms", "express foschis sharp inequalities", "sharp restriction/extension estimates" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0809.4054C" } } }