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Coalgebra Extensions and Algebra Coextensions of Galois Type

Tomasz Brzezinski·Piotr M. Hajac
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Abstract

The notion of a coalgebra-Galois extension is defined as a natural generalisation of a Hopf-Galois extension. It is shown that any coalgebra-Galois extension induces a unique entwining map $ψ$ compatible with the right coaction. For the dual notion of an algebra-Galois coextension it is also proven that there always exists a unique entwining structure compatible with the right action.

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BibTeXRIS

Tomasz Brzezinski, Piotr M. Hajac. 1998-06-21. Coalgebra Extensions and Algebra Coextensions of Galois Type. https://arxiv.org/abs/q-alg/9708010

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