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arXiv · 2210.03891

Trace ideal and annihilator of Ext and Tor of regular fractional ideals, and some applications

Souvik Dey
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Abstract

Given a commutative Noetherian ring $R$ with total ring of fractions $Q(R)$, and a finitely generated $R$-submodule $M$ of $Q(R)$, we prove an equality between trace ideal, and certain annihilator of Ext and Tor of $M$. As a consequence, we answer in one-dimensional local analytically unramified case, a question raised by the present author and R. Takahashi. As another application, we give an alternative proof of a recent result of \"O. Esentepe that for one-dimensional analytically unramified Gorenstein local rings, the cohomology annihilator of Iyengar and Takahashi coincides with the conductor ideal.

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Souvik Dey. 2022-10-08. Trace ideal and annihilator of Ext and Tor of regular fractional ideals, and some applications. https://arxiv.org/abs/2210.03891

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