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Twistings, crossed coproducts and Hopf-Galois coextensions

S. Caenepeel·Dingguo Wang·Yanxin Wang
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Abstract

Let $H$ be a Hopf algebra. Ju and Cai introduced the notion of twisting of an $H$-module coalgebra. In this note, we study the relationship between twistings, crossed coproducts and Hopf-Galois coextensions. In particular, we show that a twisting of an $H$-Galois coextension remains $H$-Galois if the twisting is invertible.

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BibTeXRIS

S. Caenepeel, Dingguo Wang, Yanxin Wang. 2002-10-30. Twistings, crossed coproducts and Hopf-Galois coextensions. https://arxiv.org/abs/math/0210460

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