We show the close connection between apparently different Galois theories for comodules
introduced recently in [J. Gómez-Torrecillas and J. Vercruysse, Comatrix corings and Galois …

Publisher Summary A coring is one of the most basic algebraic structures dual to that of a
ring (but also a ring itself can be viewed as a coring). The notion of a coring appeared first in …

This work is written as a PhD thesis under the supervision of Professor Stefaan Caenepeel.
The thesis was defended on March 9, 2007 at the Vrije Universiteit Brussel (Free University …

We show that there exists a Galois correspondence between subalgebras of an H-comodule
algebra A over a base ring R and generalised quotients of a Hopf algebra H if both A and H …

The relations between various categories A and B are described by functors and important
examples for these are the equivalences between categories. They are often of the form …

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 …

The coordinate algebras of algebraic groups provide classical examples of Hopf algebras
and the interaction between Hopf algebra theory and algebraic geometry that arises from …