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arXiv · 2004.03709

Integral and quasi-abelian hearts of twin cotorsion pairs on extriangulated categories

Souheila Hassoun·Amit Shah
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Abstract

It was shown recently that the heart of a twin cotorsion pair ((S,T),(U,V)) on an extriangulated category is semi-abelian. We provide a sufficient condition for the heart to be integral and another for the heart to be quasi-abelian. This unifies and improves the corresponding results for exact and triangulated categories. Furthermore, if T=U, then we show that the Gabriel-Zisman localisation of the heart at the class of its regular morphisms is equivalent to the heart of the single twin cotorsion pair (S,T). This generalises and improves the known result for triangulated categories, thereby providing new insights in the exact setting.

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Souheila Hassoun, Amit Shah. 2020-05-20. Integral and quasi-abelian hearts of twin cotorsion pairs on extriangulated categories. https://doi.org/10.1080/00927872.2020.1779737

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