Copointed Hopf algebras over ${\mathbb{S}}_4$

Abstract

We study the realizations of certain braided vector spaces of rack type as Yetter-Drinfeld modules over a cosemisimple Hopf algebra $H$. We apply the strategy developed in arXiv:1212.5279 to compute their liftings and use these results to obtain the classification of finite-dimensional copointed Hopf algebras over ${\mathbb{S}}_4$.

27 pages. New title

References in corpus (1)

• On rigidity of Nichols algebras