{ "id": "1907.12620", "version": "v1", "published": "2019-07-29T20:03:45.000Z", "updated": "2019-07-29T20:03:45.000Z", "title": "Algebraic $h$-vectors of simplicial complexes through local cohomology, part 1", "authors": [ "Connor Sawaske" ], "categories": [ "math.CO", "math.AC" ], "abstract": "Given an infinite field $\\mathbb{k}$ and a simplicial complex $\\Delta$, a common theme in studying the $f$- and $h$-vectors of $\\Delta$ has been the consideration of the Hilbert series of the Stanley--Reisner ring $\\mathbb{k}[\\Delta]$ modulo a generic linear system of parameters $\\Theta$. Historically, these computations have been restricted to special classes of complexes (most typically triangulations of spheres or manifolds). We provide a compact topological expression of $h_{d-1}^\\mathfrak{a}(\\Delta)$, the dimension over $\\mathbb{k}$ in degree $d-1$ of $\\mathbb{k}[\\Delta]/(\\Theta)$, for any complex $\\Delta$ of dimension $d-1$. In the process, we provide tools and techniques for the possible extension to other coefficients in the Hilbert series.", "revisions": [ { "version": "v1", "updated": "2019-07-29T20:03:45.000Z" } ], "analyses": { "subjects": [ "14F55", "05E45" ], "keywords": [ "simplicial complex", "local cohomology", "hilbert series", "generic linear system", "common theme" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }