De-equivariantization of Hopf algebras.


We study the de-equivariantization of a Hopf algebra by an affine group scheme and we apply Tannakian techniques in order to realize it as the tensor category of comodules over a coquasi-bialgebra. As an application we construct a family of coquasi-Hopf algebras $A(H, G, \Phi)$ attached to a coradically-graded pointed Hopf algebra $H$ and some extra data.

Algebr. Represent. Theory 17 (2014), no. 1, 161–180