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arXiv · 1903.05847

Measuring the non-Gorenstein locus of Hibi rings and normal affine semigroup rings

Jürgen Herzog·Fatemeh Mohammadi·Janet Page
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Abstract

The trace of the canonical module of a Cohen-Macaulay ring describes its non-Gorenstein locus. We study the trace of the canonical module of a Segre product of algebras, and we apply our results to compute the non-Gorenstein locus of toric rings. We provide several sufficient and necessary conditions for Hibi rings and normal semigroup rings to be Gorenstein on the punctured spectrum.

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Jürgen Herzog, Fatemeh Mohammadi, Janet Page. 2019-03-14. Measuring the non-Gorenstein locus of Hibi rings and normal affine semigroup rings. https://doi.org/10.1016/j.jalgebra.2019.08.028

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