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arXiv · 2510.05720

Annihilation of cohomology over one dimensional almost Gorenstein rings

Özgür Esentepe
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Abstract

Given a Cohen-Macaulay local ring, the cohomology annihilator ideal and the annihilator of the stable category of maximal Cohen-Macaulay modules are two ideals closely related both with each other and the singularities of the ring. Kimura recently showed that the two ideals agree up to radicals. In this article, we give a sufficient condition for the two ideals to be equal. As an application, we show that the cohomology annihilator ideal of a one dimensional analytically unramified almost Gorenstein complete local ring agrees with the conductor ideal.

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Özgür Esentepe. 2025-10-07. Annihilation of cohomology over one dimensional almost Gorenstein rings. https://arxiv.org/abs/2510.05720

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