{ "id": "1005.5534", "version": "v2", "published": "2010-05-30T14:21:18.000Z", "updated": "2010-06-05T07:10:49.000Z", "title": "Linear ROD subsets of Borel partial orders are countably cofinal in Solovay's model", "authors": [ "Vladimir Kanovei" ], "comment": "5 pages", "categories": [ "math.LO" ], "abstract": "The following is true in the Solovay model. 1. If $\\leq$ is a Borel partial quasi-order on a Borel set $D$ of the reals, $X$ is a ROD subset of $D$, and $\\leq$ restricted to $X$ is linear, then $X$ is countably cofinal in the sense of $\\leq$. 2. If in addition every countable set $Y$ of $D$ has a strict upper bound in the sense of $\\leq$, then the ordering $< D ; \\leq >$ has no maximal chains that are ROD sets.", "revisions": [ { "version": "v2", "updated": "2010-06-05T07:10:49.000Z" } ], "analyses": { "subjects": [ "03E15" ], "keywords": [ "linear rod subsets", "borel partial orders", "countably cofinal", "solovays model", "borel partial quasi-order" ], "note": { "typesetting": "TeX", "pages": 5, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1005.5534K" } } }