{ "id": "1807.10171", "version": "v1", "published": "2018-07-26T14:43:35.000Z", "updated": "2018-07-26T14:43:35.000Z", "title": "Section problems for configurations of points on the Riemann sphere", "authors": [ "Lei Chen", "Nick Salter" ], "comment": "25 pages with 4 figures", "categories": [ "math.GT", "math.AG", "math.GR" ], "abstract": "This paper contains a suite of results concerning the problem of adding $m$ distinct new points to a configuration of $n$ distinct points on the Riemann sphere, such that the new points depend continuously on the old. Altogether, the results of the paper provide a complete answer to the following question: given $n \\ne 5$, for which $m$ can one continuously add $m$ points to a configuration of $n$ points? For $n \\ge 6$, we find that $m$ must be divisible by $n(n-1)(n-2)$, and we provide a construction based on the idea of cabling of braids. For $n = 3,4$, we give some exceptional constructions based on the theory of elliptic curves.", "revisions": [ { "version": "v1", "updated": "2018-07-26T14:43:35.000Z" } ], "analyses": { "keywords": [ "riemann sphere", "section problems", "configuration", "elliptic curves", "paper contains" ], "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable" } } }