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arXiv · 1911.04722

Gorenstein Projective Objects in Comma Categories

Yeyang Peng·Rongmin Zhu·Zhaoyong Huang
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Abstract

Let $\mathcal{A}$ and $\mathcal{B}$ be abelian categories and $\mathbf{F}:\mathcal{A}\to \mathcal{B}$ an additive and right exact functor which is perfect, and let $(\mathbf{F},\mathcal{B})$ be the left comma category. We give an equivalent characterization of Gorenstein projective objects in $(\mathbf{F},\mathcal{B})$ in terms of Gorenstein projective objects in $\mathcal{B}$ and $\mathcal{A}$. We prove that there exists a left recollement of the stable category of the subcategory of $(\mathbf{F},\mathcal{B})$ consisting of Gorenstein projective objects modulo projectives relative to the same kind of stable categories in $\mathcal{B}$ and $\mathcal{A}$. Moreover, this left recollement can be filled into a recollement when $\mathcal{B}$ is Gorenstein and $\mathbf{F}$ preserves projectives.

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Yeyang Peng, Rongmin Zhu, Zhaoyong Huang. 2019-11-12. Gorenstein Projective Objects in Comma Categories. https://arxiv.org/abs/1911.04722

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