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arXiv · 2608.03766

A Fitting criterion for quasi-Gorenstein local rings

Sora Miyashita
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Abstract

Let $(R,\mathfrak m)$ be a Noetherian local ring admitting a canonical module $\omega_R$. We prove that $R$ is quasi-Gorenstein if and only if $\operatorname{Fitt}_1^R(\omega_R)\cong\omega_R$. When $R$ is Cohen-Macaulay, the same condition characterizes the Gorenstein property, confirming an expectation of Eisenbud, Ficarra, Herzog, and Moradi and extending their result for canonical ideals in local Cohen--Macaulay domains of type at most two.

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Sora Miyashita. 2026-08-04. A Fitting criterion for quasi-Gorenstein local rings. https://arxiv.org/abs/2608.03766

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