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arXiv · 1703.08721

Change of grading, injective dimension and dualizing complexes

Andrea Solotar·Pablo Zadunaisky
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Abstract

Let $G,H$ be groups, $\phi: G \rightarrow H$ a group morphism, and $A$ a $G$-graded algebra. The morphism $\phi$ induces an $H$-grading on $A$, and on any $G$-graded $A$-module, which thus becomes an $H$-graded $A$-module. Given an injective $G$-graded $A$-module, we give bounds for its injective dimension when seen as $H$-graded $A$-module. Following ideas by Van den Bergh, we give an application of our results to the stability of dualizing complexes through change of grading.

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Andrea Solotar, Pablo Zadunaisky. 2017-03-25. Change of grading, injective dimension and dualizing complexes. https://arxiv.org/abs/1703.08721

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