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arXiv · 1302.2991

Torsion pairs and filtrations in abelian categories with tilting objects

Jason Lo
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Abstract

Given a noetherian abelian category $\mathcal Z$ of homological dimension two with a tilting object $T$, the abelian category $\mathcal Z$ and the abelian category of modules over $\text{End} (T)^{\textit{op}}$ are related by a sequence of two tilts; we give an explicit description of the torsion pairs involved. We then use our techniques to obtain a simplified proof of a theorem of Jensen-Madsen-Su, that $\mathcal Z$ has a three-step filtration by extension-closed subcategories. Finally, we generalise Jensen-Madsen-Su's filtration to a noetherian abelian category of any finite homological dimension.

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Jason Lo. 2013-02-13. Torsion pairs and filtrations in abelian categories with tilting objects. https://arxiv.org/abs/1302.2991

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