Abstract
For an algebra A, a coalgebra C and a lax entwining structure (A, C, ψ), in this paper we introduce the notions of lax C-Galois extension with normal basis and lax C-cleft extension and we prove that these notions are equivalent if the functor A ⊗ — preserve coequalizers.
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Alonso Álvarez, J.N., Fernández Vilaboa, J.M., González Rodríguez, R. et al. Lax entwining structures, groupoid algebras and cleft extensions. Bull Braz Math Soc, New Series 45, 133–178 (2014). https://doi.org/10.1007/s00574-014-0044-z
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DOI: https://doi.org/10.1007/s00574-014-0044-z
Keywords
- lax
- partial and weak entwining structure
- weak Hopf algebra
- groupoid algebra
- Galois object
- cleft extension
- normal basis