{ "id": "0910.0120", "version": "v1", "published": "2009-10-01T09:36:52.000Z", "updated": "2009-10-01T09:36:52.000Z", "title": "Inversion of series and the cohomology of the moduli spaces $\\mathcal{M}^δ_{0,n}$", "authors": [ "Francis Brown", "Jonas Bergström" ], "categories": [ "math.AG" ], "abstract": "For $n\\geq 3$, let $\\mathcal{M}_{0,n}$ denote the moduli space of genus 0 curves with $n$ marked points, and $\\overline{\\mathcal{M}}_{0,n}$ its smooth compactification. A theorem due to Ginzburg, Kapranov and Getzler states that the inverse of the exponential generating series for the Poincar\\'e polynomial of $H^{\\bullet}(\\mathcal{M}_{0,n})$ is given by the corresponding series for $H^{\\bullet}(\\overline{\\mathcal{M}}_{0,n})$. In this paper, we prove that the inverse of the ordinary generating series for the Poincar\\'e polynomial of $H^{\\bullet}(\\mathcal{M}_{0,n})$ is given by the corresponding series for $H^{\\bullet}(\\mathcal{M}^{\\delta}_{0,n})$, where $\\mathcal{M}_{0,n}\\subset \\mathcal{M}^{\\delta}_{0,n} \\subset \\overline{\\mathcal{M}}_{0,n}$ is a certain smooth affine scheme.", "revisions": [ { "version": "v1", "updated": "2009-10-01T09:36:52.000Z" } ], "analyses": { "subjects": [ "14H10" ], "keywords": [ "moduli space", "cohomology", "poincare polynomial", "smooth affine scheme", "corresponding series" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0910.0120B" } } }