Homotopic Hopf-Galois extensions: foundations and examples

  title={Homotopic Hopf-Galois extensions: foundations and examples},
  author={Kathryn Hess},
  journal={Geometry and Topology Monographs},
  • K. Hess
  • Published 19 February 2009
  • Mathematics
  • Geometry and Topology Monographs
Hopf‐Galois extensions of rings generalize Galois extensions, with the coaction of a Hopf algebra replacing the action of a group. Galois extensions with respect to a group G are the Hopf‐Galois extensions with respect to the dual of the group algebra of G . Rognes recently defined an analogous notion of Hopf‐Galois extensions in the category of structured ring spectra, motivated by the fundamental example of the unit map from the sphere spectrum to MU . This article introduces a theory of… Expand

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