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arXiv · 0711.3642

Galois theory in bicategories

Jose Gomez-Torrecillas·Joost Vercruysse
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Abstract

We develop a Galois (descent) theory for comonads within the framework of bicategories. We give generalizations of Beck's theorem and the Joyal-Tierney theorem. Many examples are provided, including classical descent theory, Hopf-Galois theory over Hopf algebras and Hopf algebroids, Galois theory for corings and group-corings, and Morita-Takeuchi theory for corings. As an application we construct a new type of comatrix corings based on (dual) quasi bialgebras.

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Jose Gomez-Torrecillas, Joost Vercruysse. 2007-11-22. Galois theory in bicategories. https://arxiv.org/abs/0711.3642

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