Lie theory and the Chern-Weil homomorphism

A. Alekseev; E. Meinrenken

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arXiv · math/0308135

Lie theory and the Chern-Weil homomorphism

A. Alekseev·E. Meinrenken

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Abstract

We introduce a canonical Chern-Weil map for possibly non-commutative g-differential algebras with connection. Our main observation is that the generalized Chern-Weil map is an algebra homomorphism ``up to g-homotopy''. Hence, the induced map from invariant polynomials to the basic cohomology is an algebra homomorphism. As in the standard Chern-Weil theory, this map is independent of the choice of connection. Applications of our results include: a conceptually easy proof of the Duflo theorem for quadratic Lie algebras, a short proof of a conjecture of Vogan on Dirac cohomology, generalized Harish-Chandra projections for quadratic Lie algebras, an extension of Rouviere's theorem for symmetric pairs, and a new construction of universal characteristic forms in the Bott-Shulman complex.

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BibTeX RIS

A. Alekseev, E. Meinrenken. 2003-08-14. Lie theory and the Chern-Weil homomorphism. https://arxiv.org/abs/math/0308135

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