{ "id": "1602.03209", "version": "v1", "published": "2016-02-09T22:09:34.000Z", "updated": "2016-02-09T22:09:34.000Z", "title": "The quandary of quandles: The Borel completeness of a knot invariant", "authors": [ "Andrew D. Brooke-Taylor", "Sheila K. Miller" ], "comment": "12 pages", "categories": [ "math.LO", "math.RA" ], "abstract": "The isomorphism type of the knot quandle introduced by Joyce is a complete invariant of tame knots. Whether two quandles are isomorphic is in practice difficult to determine; we show that this question is provably hard: isomorphism of quandles is Borel complete. The class of tame knots, however, is trivial from the perspective of Borel reducibility, suggesting that equivalence of tame knots may be reducible to a more tractable isomorphism problem.", "revisions": [ { "version": "v1", "updated": "2016-02-09T22:09:34.000Z" } ], "analyses": { "subjects": [ "20N99", "03E15", "57M27" ], "keywords": [ "borel completeness", "knot invariant", "tame knots", "complete invariant", "isomorphism type" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2016arXiv160203209B" } } }