{ "id": "2306.11001", "version": "v1", "published": "2023-06-19T15:07:51.000Z", "updated": "2023-06-19T15:07:51.000Z", "title": "On homology concordance in contractible manifolds and two bridge links", "authors": [ "Hugo Zhou" ], "comment": "39 pages, 18 figures", "categories": [ "math.GT" ], "abstract": "Let $\\widehat{\\mathcal{C}}_\\mathbb{Z}$ be the group consists of manifold-knot pairs $(Y,K)$ modulo homology concordance, where $Y$ is an integer homology sphere bounding an integer homology ball, and let $\\mathcal{C}_\\mathbb{Z}$ be the subgroup consisting of pairs $(S^3,K)$. Dai-Hom-Stoffregen-Truong show that the quotient group ${\\widehat{\\mathcal{C}}_\\mathbb{Z}}/{\\mathcal{C}_\\mathbb{Z}}$ admits a $\\mathbb{Z}^\\infty$-summand. In this paper, we improve the result by showing that there exists a family $\\{(Y,K_m)\\}_{m>1 }$ generating the $\\mathbb{Z}^\\infty$-summand where $Y$ is the boundary of a smooth contractible $4$-manifold. In fact, we give a $\\mathbb{Z}$-count of such families. The examples are constructed using a family of knots obtained by blowing down a component of a two-bridge link. They are studied in Jonathan Hales's thesis. Using the algorithm due to Ozsv\\'{a}th, Szab\\'{o} and Hales we give a classification of the knot Floer homology of a larger family of such knots, that might be of independent interest.", "revisions": [ { "version": "v1", "updated": "2023-06-19T15:07:51.000Z" } ], "analyses": { "keywords": [ "bridge links", "contractible manifolds", "integer homology ball", "knot floer homology", "modulo homology concordance" ], "note": { "typesetting": "TeX", "pages": 39, "language": "en", "license": "arXiv", "status": "editable" } } }