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arXiv · 1508.07552

Canonical and $n$-canonical modules on a Noetherian algebra

Mitsuyasu Hashimoto
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Abstract

We define canonical and $n$-canonical modules on a module-finite algebra over a Noether commutative ring and study their basic properties. Using $n$-canonical modules, we generalize a theorem on $(n,C)$-syzygy by Araya and Iima which generalize a well-known theorem on syzygies by Evans and Griffith. Among others, we prove a non-commutative version of Aoyama's theorem which states that a canonical module descends with respect to a flat local homomorphism. We also prove the codimension two-argument for modules over a coherent sheaf of algebras with a $2$-canonical module, generalizing a result of the author.

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Mitsuyasu Hashimoto. 2015-08-30. Canonical and $n$-canonical modules on a Noetherian algebra. https://arxiv.org/abs/1508.07552

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