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arXiv · 2605.02029

Quasi-Gorenstein morphisms of commutative local dg-algebras

Zachary Nason·Andrew J. Soto Levins·Ryan Watson
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Abstract

We introduce quasi-Gorenstein morphisms of commutative local dg-algebras and use a Gorenstein version of the virtually small property to characterize them, a result which is new even for homomorphisms of local rings. In a different direction, we characterize exact sequences in a noetherian local ring, in the sense of Avramov, Henriques, and \c{S}ega, in terms of quasi-Gorenstein morphisms involving Koszul complexes.

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Zachary Nason, Andrew J. Soto Levins, Ryan Watson. 2026-05-03. Quasi-Gorenstein morphisms of commutative local dg-algebras. https://arxiv.org/abs/2605.02029

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