{ "id": "1211.3350", "version": "v3", "published": "2012-11-14T16:28:09.000Z", "updated": "2013-03-03T18:18:54.000Z", "title": "Base Tree Property", "authors": [ "Bohuslav Balcar", "Michal Doucha", "Michael Hrušák" ], "categories": [ "math.LO" ], "abstract": "Building on previous work of [BPS] we investigate $\\sigma$-closed partial orders of size continuum. We provide both an internal and external characterization of such partial orders by showing that (1) every $\\sigma$-closed partial order of size continuum has a base tree and that (2) $\\sigma$-closed forcing notions of density $\\mathfrak c$ correspond exactly to regular suborders of the collapsing algebra $Coll(\\omega_1, 2^\\omega)$. We further study some naturally ocurring examples of such partial orders.", "revisions": [ { "version": "v3", "updated": "2013-03-03T18:18:54.000Z" } ], "analyses": { "keywords": [ "base tree property", "closed partial order", "size continuum", "external characterization", "regular suborders" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1211.3350B" } } }