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arXiv · 1511.09320

Pointed Hopf actions on fields, II

Pavel Etingof·Chelsea Walton
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Abstract

This is a continuation of the authors' study of finite-dimensional pointed Hopf algebras H which act inner faithfully on commutative domains. As mentioned in Part I of this work, the study boils down to the case where H acts inner faithfully on a field. These Hopf algebras are referred to as Galois-theoretical. In this work, we provide classification results for finite-dimensional pointed Galois-theoretical Hopf algebras H of finite Cartan type. Namely, we determine when such H of type A_1^{\times r} and some H of rank two possess the Galois-theoretical property. Moreover, we provide necessary and sufficient conditions for Reshetikhin twists of small quantum groups to be Galois-theoretical.

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Pavel Etingof, Chelsea Walton. 2015-11-30. Pointed Hopf actions on fields, II. https://arxiv.org/abs/1511.09320

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