Spectral Flows of Dilations of Fredholm Operators

@article{DeNittis2014SpectralFO,
  title={Spectral Flows of Dilations of Fredholm Operators},
  author={Giuseppe De Nittis and Hermann Schulz-Baldes},
  journal={Canadian Mathematical Bulletin},
  year={2014},
  volume={58},
  pages={51 - 68}
}
Abstract Given an essentially unitary contraction and an arbitrary unitary dilation of it, there is a naturally associated spectral flow that is shown to be equal to the index of the operator. This result is interpreted in terms of the K-theory of an associated mapping cone. It is then extended to connect Z2 indices of odd symmetric Fredholm operators to a Z2-valued spectral flow. 

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