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The Chern-Galois character

Tomasz Brzezinski·Piotr M. Hajac
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Abstract

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 thus obtained modules.

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Tomasz Brzezinski, Piotr M. Hajac. 2003-06-30. The Chern-Galois character. https://arxiv.org/abs/math/0306436

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