Twistings, crossed coproducts and Hopf-Galois coextensions

2002/10/30 by S. Caenepeel, Caenepeel, S., Dingguo Wang +3
Mathematics · Physics and Astronomy · #16W30 #Advanced Topics in Algebra #Algebraic structures and combinatorial models #FOS: Mathematics #Nonlinear Waves and Solitons #Quantum Algebra (math.QA) #Rings and Algebras (math.RA) #math.QA #math.RA #msc:16W30

paper · pdf · doi:10.48550/arxiv.math/0210460

20 pages

arxiv created 2002/10/30 · openalex publication_date 2002/10/30 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Let H be a Hopf algebra. Ju and Cai introduced the notion of twisting of an H-module coalgebra. In this note, we study the relationship between twistings, crossed coproducts and Hopf-Galois coextensions. In particular, we show that a twisting of an H-Galois coextension remains H-Galois if the twisting is invertible.

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