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arXiv · 2308.05706

A remark on the Galois-type correspondence between ideal coideals and comodule subrings of a Hopf algebroid

Paolo Saracco
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Abstract

We exhibit a bijective correspondence between certain left ideal coideals in a Hopf algebroid for which the resulting quotient is a coequalizer and certain right coideal subrings which are themselves an equalizer, remarkably improving a recent result of the author obtained in collaboration with L. El Kaoutit, A. Ghobadi and J. Vercruysse. Interpreting this result in the Hopf algebra setting provides a bijective correspondence which extends the previously known cases.

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Paolo Saracco. 2023-08-10. A remark on the Galois-type correspondence between ideal coideals and comodule subrings of a Hopf algebroid. https://arxiv.org/abs/2308.05706

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