{ "id": "1101.2218", "version": "v1", "published": "2011-01-11T21:40:26.000Z", "updated": "2011-01-11T21:40:26.000Z", "title": "Null-orbit reflexive operators", "authors": [ "Don Hadwin", "Ileana Ionascu", "Hassan Yousefi" ], "categories": [ "math.FA", "math.OA" ], "abstract": "We introduce and study the notion of null-orbit reflexivity, which is a slight perturbation of the notion of orbit-reflexivity. Positive results for orbit reflexivity and the recent notion of $\\mathbb{C}$-orbit reflexivity both extend to null-orbit reflexivity. Of the two known examples of operators that are not orbit-reflexive, one is null-orbit reflexive and the other is not. The class of null-orbit reflexive operators includes the classes of hyponormal, algebraic, compact, strictly block-upper (lower) triangular operators, and operators whose spectral radius is not 1. We also prove that every polynomially bounded operator on a Hilbert space is both orbit-reflexive and null-orbit reflexive.", "revisions": [ { "version": "v1", "updated": "2011-01-11T21:40:26.000Z" } ], "analyses": { "keywords": [ "null-orbit reflexive operators", "null-orbit reflexivity", "triangular operators", "spectral radius", "hilbert space" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1101.2218H" } } }