{ "id": "2103.08702", "version": "v1", "published": "2021-03-15T20:29:19.000Z", "updated": "2021-03-15T20:29:19.000Z", "title": "Multiplicative finite embeddability vs divisibility of ultrafilters", "authors": [ "Boris Ĺ obot" ], "categories": [ "math.LO" ], "abstract": "We continue the exploration of various aspects of divisibility of ultrafilters, adding one more relation to the picture: multiplicative finite embeddability. We show that it lies between divisibility relations $\\mid_M$ and $\\widetilde{\\mid}$. The set of its minimal elements proves to be very rich, and the $\\widetilde{\\mid}$-hierarchy is used to get a better intuition of this richness. We find the place of the set of $\\widetilde{\\mid}$-maximal ultrafilters among some known families of ultrafilters. Finally, we introduce new notions of largeness of subsets of $\\mathbb{N}$, and compare it to other such notions, important for infinite combinatorics and topological dynamics.", "revisions": [ { "version": "v1", "updated": "2021-03-15T20:29:19.000Z" } ], "analyses": { "subjects": [ "54D35", "54D80", "11U99", "03E05", "03H15" ], "keywords": [ "multiplicative finite embeddability", "infinite combinatorics", "minimal elements", "better intuition", "maximal ultrafilters" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }