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arXiv · 1607.06189

Syzygies of Cohen-Macaulay modules and Grothendieck groups

Toshinori Kobayashi
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Abstract

We study the converse of a theorem of Butler and Auslander-Reiten. We show that a Cohen-Macaulay local ring with an isolated singularity has only finitely many isomorphism classes of indecomposable summands of syzygies of Cohen-Macaulay modules if the Auslander-Reiten sequences generate the relation of the Grothendieck group of finitely generated modules. This extends a recent result of Hiramatsu, which gives an affirmative answer in the Gorenstein case to a conjecture of Auslander.

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Toshinori Kobayashi. 2016-07-21. Syzygies of Cohen-Macaulay modules and Grothendieck groups. https://arxiv.org/abs/1607.06189

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