The K-homology of nets of C*-algebras

  title={The K-homology of nets of C*-algebras},
  author={Giuseppe Ruzzi and Ezio Vasselli},
  journal={Journal of Geometry and Physics},
Let X be a space, intended as a possibly curved space–time, and A a precosheaf of C∗-algebras on X. Motivated by algebraic quantum field theory, we study the Kasparov and Θ-summable K-homology of A interpreting them in terms of the holonomy equivariant K-homology of the associated C∗-dynamical system. This yields a characteristic class for K-homology cycles of A with values in the odd cohomology of X, that we interpret as a generalized statistical dimension. 
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