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arXiv · 2007.10197

Nakayama automorphisms of graded Ore extensions of Koszul Artin-Schelter regular algebras

Y. Shen·Y. Guo
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Abstract

Let $A$ be a Koszul Artin-Schelter regular algebra, $\sigma$ a graded automorphism of $A$ and $\delta$ a degree-one $\sigma$-derivation of $A$. We introduce an invariant for $\delta$ called the $\sigma$-divergence of $\delta$. We describe the Nakayama automorphism of the graded Ore extension $B=A[z;\sigma,\delta]$ explicitly using the $\sigma$-divergence of $\delta$, and construct a twisted superpotential $\hat{\omega}$ for $B$ so that it is a derivation quotient algebra defined by $\hat{\omega}$. We also determine all graded Ore extensions of noetherian Artin-Schelter regular algebras of dimension 2 and compute their Nakayama automorphisms.

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Y. Shen, Y. Guo. 2020-07-20. Nakayama automorphisms of graded Ore extensions of Koszul Artin-Schelter regular algebras. https://arxiv.org/abs/2007.10197

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