{ "id": "math/0409348", "version": "v1", "published": "2004-09-20T18:58:07.000Z", "updated": "2004-09-20T18:58:07.000Z", "title": "A Septic with 99 real Nodes", "authors": [ "Oliver Labs" ], "comment": "11 pages, 4 figures. For more images/movies, see http://www.AlgebraicSurface.net", "categories": [ "math.AG" ], "abstract": "We find a surface of degree 7 in real projective three-space P^3(R) with 99 real nodes within a family of surfaces with dihedral symmetry: First, we consider this family over some small prime fields, which allows us to test all possible parameter sets using computer algebra. In this way we find some examples of 99-nodal surfaces over some of these finite fields. Then, the examination of the geometry of these surfaces allows us to determine the parameters of a 99-nodal septic in characteristic zero. This narrows the possibilities for \\mu(7), the maximum number of nodes on a septic, to: 99 <= \\mu(7) <= 104. When reducing our surface modulo 5, we even obtain a 100-nodal septic in P^3(F_5).", "revisions": [ { "version": "v1", "updated": "2004-09-20T18:58:07.000Z" } ], "analyses": { "subjects": [ "14J17", "14Q10" ], "keywords": [ "real nodes", "small prime fields", "real projective three-space", "maximum number", "characteristic zero" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......9348L" } } }