The Chern-Galois character. (English) Zbl 1061.16037
Summary: Following the idea of Galois-type extensions and entwining structures, we define the notion of a principal extension of noncommutative algebras. We show that modules associated to such extensions via finite-dimensional corepresentations are finitely generated projective, and determine an explicit formula for the Chern character applied to the modules so obtained.
MSC:
| 16W30 | Hopf algebras (associative rings and algebras) (MSC2000) |
Keywords:
right coalgebra-Galois extensions; entwining maps; right coactions; algebra-Galois coextensions; Hopf-Galois extensions; coinvariants; right comodulesReferences:
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