{ "id": "0808.1432", "version": "v2", "published": "2008-08-11T00:18:12.000Z", "updated": "2010-01-17T17:27:27.000Z", "title": "Derivatives of Knots and Second-order Signatures", "authors": [ "Tim Cochran", "Shelly Harvey", "Constance Leidy" ], "comment": "40 pages, 22 figures, typographical corrections, to appear in Alg. Geom. Topology", "journal": "Alg. Geom. Topology 10 (2010), 739-787", "doi": "10.2140/agt.2010.10.739", "categories": [ "math.GT" ], "abstract": "We define a set of \"second-order\" L^(2)-signature invariants for any algebraically slice knot. These obstruct a knot's being a slice knot and generalize Casson-Gordon invariants, which we consider to be \"first-order signatures\". As one application we prove: If K is a genus one slice knot then, on any genus one Seifert surface, there exists a homologically essential simple closed curve of self-linking zero, which has vanishing zero-th order signature and a vanishing first-order signature. This extends theorems of Cooper and Gilmer. We introduce a geometric notion, that of a derivative of a knot with respect to a metabolizer. We also introduce a new equivalence relation, generalizing homology cobordism, called null-bordism.", "revisions": [ { "version": "v2", "updated": "2010-01-17T17:27:27.000Z" } ], "analyses": { "subjects": [ "57M25", "57M10" ], "keywords": [ "second-order signatures", "slice knot", "first-order signature", "vanishing zero-th order signature", "homologically essential simple closed curve" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 40, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0808.1432C" } } }