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arXiv · 1709.09292

Skew Calabi-Yau property of normal extensions

G. -S. Zhou·Y. Shen·D. -M. Lu
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Abstract

We prove that the skew Calabi-Yau property is preserved under normal extension for locally finite positively graded algebras. We also obtain a homological identity which describes the relationship between the Nakayama automorphisms of skew Calabi-Yau locally finite positively graded algebras and their normal extensions. As a preliminary, we show that the Nakayama automorphisms of skew Calabi-Yau algebras always send a regular normal element to a multiple of itself by a unit.

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G. -S. Zhou, Y. Shen, D. -M. Lu. 2017-09-27. Skew Calabi-Yau property of normal extensions. https://arxiv.org/abs/1709.09292

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