Abstract
We study the copointed Hopf algebras attached to the Nichols algebra of the affine rack \(\mathrm{Aff}({\mathbb F}_4,\omega )\), also known as tetrahedron rack, and the \(2\)-cocycle\(-1\). We investigate the so-called Verma modules and classify all the simple modules. We conclude that these algebras are of wild representation type and not quasitriangular, also we analyze when these are spherical.
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Acknowledgments
The authors thank professor Nicolás Andruskiewitsch for proposing this problem and useful suggestions for this article. The first author also thanks Carolina Renz for her hospitality during her stay in Córdoba. Bárbara Pogorelsky was partially supported by Capes-Brazil. Cristian Vay was partially supported by ANPCyT-Foncyt, CONICET, MinCyT (Córdoba) and Secyt (UNC).
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Pogorelsky, B., Vay, C. Representations of copointed Hopf algebras arising from the tetrahedron rack. Ann Univ Ferrara 60, 407–427 (2014). https://doi.org/10.1007/s11565-013-0197-5
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DOI: https://doi.org/10.1007/s11565-013-0197-5