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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