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Full classification of finite-dimensional Nichols algebras in Yetter–Drinfeld categories over general non-abelian groups

Classify all finite-dimensional Nichols algebras in the Yetter–Drinfeld category over kG for general finite non-abelian groups G, including specifying the permissible supports and braided structures that yield finite-dimensional Nichols algebras.

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Background

Despite major advances for abelian groups and several non-abelian families (e.g., rank-two cases and almost diagonal types), a comprehensive classification covering all finite non-abelian groups remains outstanding. Progress hinges on combining Weyl groupoid techniques, rack-cocycle realizations, and structural constraints from group generation by supports.

References

Now we assume that $G$ is a finite non abelian group. As said before, we do not have a full classification of all finite-dimensional Nichols algebras in $}{#1{\Bbbk G}$ for general $G$, but still we can go on with the remaining step of the Lifting Method by taking a fixed finite-dimensional Nichols algebra and compute all deformations of $B(V)#\Bbbk G$, as generation in degree one holds by Theorem \ref{thm:gen-deg-one-non-abelian}.

Pointed Hopf algebras revisited, with a view from tensor categories (2510.03124 - Angiono, 3 Oct 2025) in Subsection 2.4 (Pointed Hopf algebras over non-abelian groups), opening paragraph