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arXiv · 2611.01231

Partial coactions of Hopf algebras on nonunital algebras and categories

Marcelo Muniz Alves·Tiago Luiz Ferrazza
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Abstract

In this paper, we introduce and investigate partial coactions of a Hopf algebra on an associative, possibly nonunital algebra and on $\Bbbk$-linear categories. We prove that every partial coaction has a globalization in a broad sense. We study in detail the case of a partial coaction on an algebra with local units; we prove that such a coaction is always induced from a global coaction, and we show that there exists a naturally associated $\Bbbk$-linear category endowed with a partial coaction.

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Marcelo Muniz Alves, Tiago Luiz Ferrazza. 2026-10-31. Partial coactions of Hopf algebras on nonunital algebras and categories. https://arxiv.org/abs/2611.01231

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