Homological Codimension of Modular Rings of Invariants and the Koszul Complex
نویسنده
چکیده
Let ρ : G GL(n, IF) be a representation of a finite group over the field IF of characteristic p, and h1 , . . . , hm ∈IF[V ]G ivariant polynomials that form a regular sequence in IF[V ]. In this note we introduce a tool to study the problem of whether they form a regular sequence in IF[V ]G. Examples show they need not. We define the cohomology of G with coefficients in the Koszul complex
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