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Realizations of free actions via their fixed point algebras
Kay Schwieger, Stefan Wagner
Let be a compact group, let be a unital C-algebra, and let be a free C-dynamical system, in the sense of Ellwood, with fixed point alg…
An Atiyah Sequence for Noncommutative Principal Bundles
Kay Schwieger, Stefan Wagner
We present a derivation-based Atiyah sequence for noncommutative principal bundles. Along the way we treat the problem of deciding when a given -automorphism on the quantum bas…
Lifting spectral triples to noncommutative principal bundles
Kay Schwieger, Stefan Wagner
Given a free action of a compact Lie group on a unital C*-algebra and a spectral triple on the corresponding fixed point algebra , we present a sys…
Noncommutative Coverings of Quantum Tori
Kay Schwieger, Stefan Wagner
We introduce a framework for coverings of noncommutative spaces. Moreover, we study noncommutative coverings of irrational quantum tori and characterize all such coverings that are…
Part III, Free Actions of Compact Quantum Groups on C*-Algebras
Kay Schwieger, Stefan Wagner
We study and classify free actions of compact quantum groups on unital C*-algebras in terms of generalized factor systems. Moreover, we use these factor systems to show that all fi…