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arXiv · 1112.1850

Pseudodifferential extension and Todd class

Denis Perrot
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Abstract

Let M be a closed manifold. Wodzicki shows that, in the stable range, the cyclic cohomology of the associative algebra of pseudodifferential symbols of order \leq 0 is isomorphic to the homology of the cosphere bundle of M. In this article we develop a formalism which allows to calculate that, under this isomorphism, the Radul cocycle corresponds to the Poincar\'e dual of the Todd class. As an immediate corollary we obtain a purely algebraic proof of the Atiyah-Singer index theorem for elliptic pseudodifferential operators on closed manifolds.

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Denis Perrot. 2011-12-08. Pseudodifferential extension and Todd class. https://arxiv.org/abs/1112.1850

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