no. 2
Algebra/Topology
The Chern–Galois character
[Le caractère de Chern–Galois]

Présenté par : Alain Connes

Brzeziński, Tomasz1 ; Hajac, Piotr M.2, 3
1 Department of Mathematics, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK
2 Instytut Matematyczny, Polska Akademia Nauk, ul. Śniadeckich 8, Warszawa, 00-956 Poland
3 Katedra Metod Matematycznych Fizyki, Uniwersytet Warszawski ul. Hoża 74, Warszawa, 00-682 Poland
Comptes Rendus. Mathématique, Tome 338 (2004) no. 2, pp. 113-116.

Nous nous inspirons des extensions de type Galois et des structures enlacées pour définir la notion d'extension principale d'algèbres non commutatives. Nous montrons que les modules associés à de telles extensions au travers de coreprésentations de dimension finie sont projectifs et de type fini, et nous déterminons une formule explicite pour le caractère de Chern appliqué aux modules ainsi obtenus.

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.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2003.11.009
Brzeziński, Tomasz 1 ; Hajac, Piotr M. 2, 3

1 Department of Mathematics, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK
2 Instytut Matematyczny, Polska Akademia Nauk, ul. Śniadeckich 8, Warszawa, 00-956 Poland
3 Katedra Metod Matematycznych Fizyki, Uniwersytet Warszawski ul. Hoża 74, Warszawa, 00-682 Poland 
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Brzeziński, Tomasz; Hajac, Piotr M. The Chern–Galois character. Comptes Rendus. Mathématique, Tome 338 (2004) no. 2, pp. 113-116. doi : 10.1016/j.crma.2003.11.009. http://www.numdam.org/articles/10.1016/j.crma.2003.11.009/

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