{ "id": "2108.02168", "version": "v1", "published": "2021-08-04T16:51:12.000Z", "updated": "2021-08-04T16:51:12.000Z", "title": "On the commutant of $B(H)$ in its ultrapower", "authors": [ "Emmanuel Chetcuti", "Beatriz Zamora-Aviles" ], "comment": "Comments are welcome!", "categories": [ "math.FA", "math.LO" ], "abstract": "Let $B(H)$ be the algebra of bounded linear operators on a separable infinite-dimensional Hilbert space $H$. We study the commutant of $B(H)$ in its ultrapower. We characterize the class of non-principal ultrafilters for which this commutant is non-trivial. Additionally, we extend the class of ultrafilters for which the commutant is trivial.", "revisions": [ { "version": "v1", "updated": "2021-08-04T16:51:12.000Z" } ], "analyses": { "subjects": [ "46L05", "03E50" ], "keywords": [ "ultrapower", "separable infinite-dimensional hilbert space", "bounded linear operators", "non-principal ultrafilters", "non-trivial" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }