Pseudo-Galois Extensions and Hopf Algebroids

  • Lars Kadison
Conference paper
Part of the Trends in Mathematics book series (TM)


A pseudo-Galois extension is shown to be a depth two extension. Studying its left bialgebroid, we construct an enveloping Hopf algebroid for the semi-direct product of groups, or more generally involutive Hopf algebras, and their module algebras. It is a type of cofibered sum of two inclusions of the Hopf algebra into the semi-direct product and its derived right crossed product. Van Oystaeyen and Panaite observe that this Hopf algebroid is nontrivially isomorphic to a Connes-Moscovici Hopf algebroid.


Hopf Algebra Semidirect Product Algebra Homomorphism Galois Extension Base Algebra 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Birkhäuser Verlag Basel/Switzerland 2008

Authors and Affiliations

  • Lars Kadison
    • 1
  1. 1.Department of MathematicsUniversity of Pennsylvania, David Rittenhouse LaboratoryPhiladelphiaUSA

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