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arXiv · 1506.05080

Behaviour of injective dimension with respect to regradings

Andrea Solotar·Pablo Zadunaisky
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Abstract

Given a left noetherian k-algebra A graded by a group G, an injective object I in the category of G-graded A-modules and a morphism from G to another group G', we provide bounds for the injective dimension of I as a G'-graded A-module. For this, we use three change of grading functors. Most of the constructions concerning these functors work in the context of H-comodule algebras, where H is a Hopf algebra, so we develop them in this general context.

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Andrea Solotar, Pablo Zadunaisky. 2015-06-16. Behaviour of injective dimension with respect to regradings. https://arxiv.org/abs/1506.05080

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