Gorenstein cohomological dimension and stable categories for groups

Abstract

First we study the Gorenstein cohomological dimension ${\mathrm{Gcd}}_{R}G$ of groups $G$ over coefficient rings $R$, under changes of groups and rings; a characterization for finiteness of ${\mathrm{Gcd}}_{R}G$ is given. Some results in literature obtained over the coefficient ring $\mathbb{Z}$ or rings of finite global dimension are generalized to more general cases. Moreover, we establish a model structure on the weakly idempotent complete exact category $\mathcal{F}ib$ consisting of fibrant $RG$-modules, and show that the homotopy category $\mathrm{Ho}(\mathcal{F}ib)$ is triangle equivalent to both the stable category $\underline{\mathcal{C}of}(RG)$ of Benson's cofibrant modules, and the stable module category $\mathrm{StMod}(RG)$. The relation between cofibrant modules and Gorenstein projective modules is discussed, and we show that under some conditions such that ${\mathrm{Gcd}}_{R}G<\infty$, $\mathrm{Ho}(\mathcal{F}ib)$ is equivalent to the stable category of Gorenstein projective $RG$-modules, the singularity category, and the homotopy category of totally acyclic complexes of projective $RG$-modules.

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References in corpus (1)

• Frobenius functors and Gorenstein homological properties

Cited by in corpus (1)

• On some triangulated categories over group algebras