{ "id": "0811.4234", "version": "v1", "published": "2008-11-26T07:11:09.000Z", "updated": "2008-11-26T07:11:09.000Z", "title": "A non-smooth continuous unitary representation of a Banach-Lie group", "authors": [ "Daniel Beltita", "Karl-Hermann Neeb" ], "comment": "5 pages", "categories": [ "math.RT", "math.FA" ], "abstract": "In this note we show that the representation of the additive group of the Hilbert space $L^2([0,1],\\R)$ on $L^2([0,1],\\C)$ given by the multiplication operators $\\pi(f) := e^{if}$ is continuous but its space of smooth vectors is trivial. This example shows that a continuous unitary representation of an infinite dimensional Lie group need not be smooth.", "revisions": [ { "version": "v1", "updated": "2008-11-26T07:11:09.000Z" } ], "analyses": { "subjects": [ "22E65", "22E45" ], "keywords": [ "non-smooth continuous unitary representation", "banach-lie group", "infinite dimensional lie group", "smooth vectors" ], "note": { "typesetting": "TeX", "pages": 5, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0811.4234B" } } }