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arXiv · 0904.4383

Unbounded bivariant $K$-theory and correspondences in noncommutative geometry

Bram Mesland
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Abstract

By introducing a notion of smooth connection for unbounded $KK$-cycles, we show that the Kasparov product of such cycles can be defined directly, by an algebraic formula. In order to achieve this it is necessary to develop a framework of smooth algebras and a notion of differentiable $C^{*}$-module. The theory of operator spaces provides the required tools. Finally, the above mentioned $KK$-cycles with connection can be viewed as the morphisms in a category whose objects are spectral triples.

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Bram Mesland. 2009-04-28. Unbounded bivariant $K$-theory and correspondences in noncommutative geometry. https://doi.org/10.1515/crelle-2012-0076

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