{ "id": "1905.07142", "version": "v1", "published": "2019-05-17T07:30:22.000Z", "updated": "2019-05-17T07:30:22.000Z", "title": "On balanced coronas of groups", "authors": [ "Igor Protasov" ], "comment": "coarse structure, slowly oscillating functions, balanced corona", "categories": [ "math.GN" ], "abstract": "Let $G$ be an infinite group, $\\kappa$ be an infinite cardinal, $\\kappa\\leq \\mid G\\mid$ and let $\\mathcal{E}_{\\kappa}$ denotes a coarse structure on $G$ with the base $\\{\\{ (x,y): y\\in F x F\\}: F\\in [G]^{<\\kappa}\\}$. We prove that if either $\\kappa< \\mid G\\mid$ or $\\kappa= \\mid G\\mid$ and $\\kappa$ is singular then the Higson's corona $\\nu _{\\kappa} (G)$ of the coarse space $(G, \\mathcal{E}_{\\kappa})$ is a singleton. If $\\kappa= \\mid G\\mid$ and $\\kappa$ is regular then $\\nu _{\\kappa} (G)$ contains a copy of the space $U_{\\kappa}$ of $\\kappa$-uniform ultrafilters on $\\kappa$.", "revisions": [ { "version": "v1", "updated": "2019-05-17T07:30:22.000Z" } ], "analyses": { "keywords": [ "balanced coronas", "infinite cardinal", "coarse structure", "infinite group", "higsons corona" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }