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arXiv · 0708.3407

Normal Hopf subalgebras in cocycle deformations of finite groups

Cesar Galindo·Sonia Natale
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Abstract

Let $G$ be a finite group and let $π: G \to G'$ be a surjective group homomorphism. Consider the cocycle deformation $L = H^σ$ of the Hopf algebra $H = k^G$ of $k$-valued linear functions on $G$, with respect to some convolution invertible 2-cocycle $σ$. The (normal) Hopf subalgebra $k^{G'} \subseteq k^G$ corresponds to a Hopf subalgebra $L' \subseteq L$. Our main result is an explicit necessary and sufficient condition for the normality of $L'$ in $L$.

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BibTeXRIS

Cesar Galindo, Sonia Natale. 2007-11-21. Normal Hopf subalgebras in cocycle deformations of finite groups. https://arxiv.org/abs/0708.3407

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