{ "id": "1109.4367", "version": "v1", "published": "2011-09-20T17:19:54.000Z", "updated": "2011-09-20T17:19:54.000Z", "title": "New spectral multiplicities for ergodic actions", "authors": [ "Anton V. Solomko" ], "comment": "17 pages", "categories": [ "math.DS" ], "abstract": "Let G be a locally compact second countable Abelian group. Given a measure preserving action T of G on a standard probability space, let M(T) denote the set of essential values of the spectral multiplicity function of the Koopman unitary representation of G associated with T. In the case when G is either a discrete countable Abelian group or R^n, n>0, it is shown that the sets of the form {p,q,pq}, {p,q,r,pq,pr,qr,pqr} etc. or any multiplicative (and additive) subsemigroup of N are realizable as M(T) for a weakly mixing G-action T.", "revisions": [ { "version": "v1", "updated": "2011-09-20T17:19:54.000Z" } ], "analyses": { "subjects": [ "37A15", "37A30" ], "keywords": [ "ergodic actions", "compact second countable abelian group", "koopman unitary representation", "standard probability space", "discrete countable abelian group" ], "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1109.4367S" } } }