{ "id": "1709.05617", "version": "v1", "published": "2017-09-17T07:29:02.000Z", "updated": "2017-09-17T07:29:02.000Z", "title": "On eigenvalues of double branched covers", "authors": [ "Kouki Sato" ], "comment": "13 pages, 15 figures", "categories": [ "math.GT" ], "abstract": "For a given knot, we study the minimal number of positive eigenvalues of the double branched cover over spanning surfaces for the knot. The value gives a lower bound for various genera, the dealternating number and the alternation number of knots, and we prove that Batson's bound for the non-orientable 4-genus gives an estimate of the value. In addition, we use the value to give a necessary condition for being quasi-alternating.", "revisions": [ { "version": "v1", "updated": "2017-09-17T07:29:02.000Z" } ], "analyses": { "subjects": [ "57M25", "57M27" ], "keywords": [ "double branched cover", "eigenvalues", "minimal number", "lower bound", "alternation number" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }