{ "id": "1106.4354", "version": "v1", "published": "2011-06-22T00:41:33.000Z", "updated": "2011-06-22T00:41:33.000Z", "title": "Generalized support varieties for finite group schemes", "authors": [ "Eric M. Friedlander", "Julia Pevtsova" ], "journal": "Documenta Mathematica, Extra Volume Suslin (2011) 191-217", "categories": [ "math.RT" ], "abstract": "We construct two families of refinements of the (projectivized) support variety of a finite dimensional module $M$ for a finite group scheme $G$. For an arbitrary finite group scheme, we associate a family of {\\it non maximal rank varieties} $\\Gamma^j(G)_M$, $1\\leq j \\leq p-1$, to a $kG$-module $M$. For $G$ infinitesimal, we construct a finer family of locally closed subvarieties $V^{\\ul a}(G)_M$ of the variety of one parameter subgroups of $G$ for any partition $\\ul a$ of $\\dim M$. For an arbitrary finite group scheme $G$, a $kG$-module $M$ of constant rank, and a cohomology class $\\zeta$ in $\\HHH^1(G,M)$ we introduce the {\\it zero locus} $Z(\\zeta) \\subset \\Pi(G)$. We show that $Z(\\zeta)$ is a closed subvariety, and relate it to the non-maximal rank varieties. We also extend the construction of $Z(\\zeta)$ to an arbitrary extension class $\\zeta \\in \\Ext^n_G(M,N)$ whenever $M$ and $N$ are $kG$-modules of constant Jordan type.", "revisions": [ { "version": "v1", "updated": "2011-06-22T00:41:33.000Z" } ], "analyses": { "subjects": [ "16G10", "20C20", "20G10" ], "keywords": [ "generalized support varieties", "support variety", "arbitrary finite group scheme", "non maximal rank varieties", "arbitrary extension class" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1106.4354F" } } }