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arXiv · 1704.00719

Local rings with quasi-decomposable maximal ideal

Saeed Nasseh·Ryo Takahashi
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Abstract

Let $(R,\frak m)$ be a commutative noetherian local ring. In this paper, we prove that if $\frak m$ is decomposable, then for any finitely generated $R$-module $M$ of infinite projective dimension $\frak m$ is a direct summand of (a direct sum of) syzygies of $M$. Applying this result to the case where $\frak m$ is quasi-decomposable, we obtain several classfications of subcategories, including a complete classification of the thick subcategories of the singularity category of $R$.

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Saeed Nasseh, Ryo Takahashi. 2018-08-08. Local rings with quasi-decomposable maximal ideal. https://doi.org/10.1017/s0305004118000695

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