{ "id": "2404.06639", "version": "v1", "published": "2024-04-09T22:24:32.000Z", "updated": "2024-04-09T22:24:32.000Z", "title": "On cardinal invariants related to Rosenthal families and large-scale topology", "authors": [ "Arturo Martínez-Celis", "Tomasz Żuchowski" ], "comment": "19 pages", "categories": [ "math.LO" ], "abstract": "Given a function $f \\in \\omega^\\omega$, a set $A \\in [\\omega]^\\omega$ is free for $f$ if $f[A] \\cap A$ is finite. For a class of functions $\\Gamma \\subseteq \\omega^{\\omega}$, we define $\\mathfrak{ros}_\\Gamma$ as the smallest size of a family $\\mathcal{A}\\subseteq [\\omega]^\\omega$ such that for every $f\\in\\Gamma$ there is a set $A \\in \\mathcal{A}$ which is free for $f$, and $\\Delta_\\Gamma$ as the smallest size of a family $\\mathcal{F}\\subseteq\\Gamma$ such that for every $A\\in[\\omega]^\\omega$ there is $f\\in\\mathcal{F}$ such that $A$ is not free for $f$. We compare several versions of these cardinal invariants with some of the classical cardinal characteristics of the continuum. Using these notions, we partially answer some questions from arXiv:1911.01336 [math.LO] and arXiv:2004.01979 [math.GN].", "revisions": [ { "version": "v1", "updated": "2024-04-09T22:24:32.000Z" } ], "analyses": { "subjects": [ "03E17", "03E05", "03E35", "03E75" ], "keywords": [ "cardinal invariants", "rosenthal families", "large-scale topology", "smallest size", "classical cardinal characteristics" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable" } } }