… a piecewise property: given N comodule-algebra surjections P ! Pi whose kernels intersect to
zero, P is principal if and only if all Pi ’s are principal. … of principal comodule algebras over a …

… that, if we can reduce a principal comodule algebra to a piecewise-trivial principal comodule
algebra, then the comodule algebra we started from is piecewise-trivial in a specific way. …

… While the assumption of co-commutativity limits severely the applicability of the formula, it
is worth pointing out that many of the known piecewise principal comodule algebras, such as …

… analogue in the concept of principal extensions of algebras (Galois-type extensions that are
… piecewise trivial comodule algebras. We prove that such a comodule algebra P is principal …

… there are interesting piecewise principal coactions that are not algebra homomorphisms. To
… an H-comodule algebra. We call Pδ( P) the Peter-Weyl comodule algebra associated to the …

… comodule algebra of a comodule algebra P with the coacting Hopf algebra H. We prove that,
if the comodule algebra P is principal, … expect to have such a piecewise (pullback) structure …

… “noncommutative geometry” the notion of principal bundles generalizes by means of the so-…
A C-comodule M is defined to be piecewise socle-finite [92] (or quasi-finite [104]) if socS .M / …

… the notion of principal bundle are possible. It is worth mentioning principal comodule algebras,
… piecewise trivial [41], both (Q, A) and (Q0,A0) play a role, and one cannot avoid using C∗-…

… piecewise triviality to adapt the standard notion of local triviality to fibre products of C∗-algebras…
Given a bialgebra H, a right H-comodule algebra is an algebra and a right H-comodule P …

… We prove that, if the comodule algebra P is principal, then so is the … a comodule algebra P
with the coacting Hopf algebra H. To equip the join algebra P ∗H with an H-comodule algebra …