{ "id": "1612.04776", "version": "v1", "published": "2016-12-14T19:22:32.000Z", "updated": "2016-12-14T19:22:32.000Z", "title": "Embeddings of non-simply-connected 4-manifolds in 7-space. II. On the smooth classification", "authors": [ "D. Crowley", "A. Skopenkov" ], "comment": "16 pages", "categories": [ "math.GT", "math.AT" ], "abstract": "We work in the smooth category. Let $N$ be a closed connected orientable 4-manifold with torsion free $H_1$, where $H_q:=H_q(N;Z)$. Our main result is a readily calculable classification of embeddings $N\\to R^7$ up to isotopy, with an indeterminancy. Such a classification was only known before for $H_1=0$ by our earlier work from 2008. Our classification is complete when $H_2=0$ or when the signature of $N$ is divisible neither by 64 nor by 9. The group of knots $S^4\\to R^7$ acts on the set of embeddings $N\\to R^7$ up to isotopy by embedded connected sum. In Part I we classified the quotient of this action. The main novelty of this paper is the description of this action for $H_1\\ne0$, with an indeterminancy. Besides the invariants of Part I, the classification involves a refinement of the Kreck invariant from our work of 2008 which detects the action of knots. For $N=S^1\\times S^3$ we give a geometrically defined 1--1 correspondence between the set of isotopy classes of embeddings and a quotient of the set $Z\\oplus Z\\oplus Z_{12}$.", "revisions": [ { "version": "v1", "updated": "2016-12-14T19:22:32.000Z" } ], "analyses": { "subjects": [ "57R52", "57R67", "55R15" ], "keywords": [ "smooth classification", "embeddings", "isotopy classes", "indeterminancy", "smooth category" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable" } } }