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arXiv · 1705.02163

Classifications of exact structures and Cohen-Macaulay-finite algebras

Haruhisa Enomoto
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Abstract

We give a classification of all exact structures on a given idempotent complete additive category. Using this, we investigate the structure of an exact category with finitely many indecomposables. We show that the relation of the Grothendieck group of such a category is generated by AR conflations. Moreover, we obtain an explicit classification of (1) Gorenstein-projective-finite Iwanaga-Gorenstein algebras, (2) Cohen-Macaulay-finite orders, and more generally, (3) cotilting modules $U$ with $^\perp U$ of finite type. In the appendix, we develop the AR theory of exact categories over a noetherian complete local ring, and relate the existence of AR conflations to the AR duality and dualizing varieties.

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Haruhisa Enomoto. 2017-05-05. Classifications of exact structures and Cohen-Macaulay-finite algebras. https://doi.org/10.1016/j.aim.2018.07.022

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