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arXiv · 1808.04297

Relative rigid objects in triangulated categories

Changjian Fu·Shengfei Geng·Pin Liu
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Abstract

Let $\mathcal{T}$ be a Krull-Schmidt, Hom-finite triangulated category with suspension functor $[1]$. Let $R$ be a basic rigid object, $Γ$ the endomorphism algebra of $R$, and $\operatorname{\mathsf{pr}}(R)\subseteq \mathcal{T}$ the subcategory of objects finitely presented by $R$. We investigate the relative rigid objects, \ie $R[1]$-rigid objects of $\mathcal{T}$. Our main results show that the $R[1]$-rigid objects in $\operatorname{\mathsf{pr}}(R)$ are in bijection with $τ$-rigid $Γ$-modules, and the maximal $R[1]$-rigid objects with respect to $\operatorname{\mathsf{pr}}(R)$ are in bijection with support $τ$-tilting $Γ$-modules. We also show that various previously known bijections involving support $τ$-tilting modules are recovered under respective assumptions.

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Changjian Fu, Shengfei Geng, Pin Liu. 2018-09-08. Relative rigid objects in triangulated categories. https://arxiv.org/abs/1808.04297

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