{ "id": "2104.09150", "version": "v1", "published": "2021-04-19T09:17:10.000Z", "updated": "2021-04-19T09:17:10.000Z", "title": "A guessing principle from a Souslin tree, with applications to topology", "authors": [ "Assaf Rinot", "Roy Shalev" ], "categories": [ "math.LO", "math.GN" ], "abstract": "We introduce a new combinatoiral principle which we call $\\clubsuit_{AD}$. This principle asserts the existence of a certain multi-ladder system with guessing and almost-disjointness features, and is shown to be sufficient for carrying out de Caux type constructions of topological spaces. Our main result states that strong instances of $\\clubsuit_{AD}$ follow from the existence of a Souslin tree. It is also shown that the weakest instance of $\\clubsuit_{AD}$ does not follow from the existence of an almost Souslin tree. As an application, we obtain a simple, de Caux type proof of Rudin's result that if there is a Souslin tree, then there is an $S$-space which is Dowker.", "revisions": [ { "version": "v1", "updated": "2021-04-19T09:17:10.000Z" } ], "analyses": { "subjects": [ "03E05", "54G20", "03E35", "03E65" ], "keywords": [ "souslin tree", "guessing principle", "application", "caux type proof", "caux type constructions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }