{ "id": "0907.0302", "version": "v5", "published": "2009-07-02T07:31:18.000Z", "updated": "2011-01-22T19:59:15.000Z", "title": "Gröbner strata in the Hilbert scheme of points", "authors": [ "Mathias Lederer" ], "comment": "47 pages, 6 figures, 11 examples", "categories": [ "math.AG", "math.AC" ], "abstract": "The present paper shall provide a framework for working with Gr\\\"obner bases over arbitrary rings $k$ with a prescribed finite standard set $\\Delta$. We show that the functor associating to a $k$-algebra $B$ the set of all reduced Gr\\\"obner bases with standard set $\\Delta$ is representable and that the representing scheme is a locally closed stratum in the Hilbert scheme of points. We cover the Hilbert scheme of points by open affine subschemes which represent the functor associating to a $k$-algebra $B$ the set of all border bases with standard set $\\Delta$ and give reasonably small sets of equations defining these schemes. We show that the schemes parametrizing Gr\\\"obner bases are connected; give a connectedness criterion for the schemes parametrizing border bases; and prove that the decomposition of the Hilbert scheme of points into the locally closed strata parametrizing Gr\\\"obner bases is not a stratification.", "revisions": [ { "version": "v5", "updated": "2011-01-22T19:59:15.000Z" } ], "analyses": { "subjects": [ "14C05", "13F20", "13P10" ], "keywords": [ "hilbert scheme", "gröbner strata", "locally closed stratum", "open affine subschemes", "prescribed finite standard set" ], "note": { "typesetting": "TeX", "pages": 47, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0907.0302L" } } }