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On the noncommutative spectral flow

Charlotte Wahl
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Abstract

We define and study the noncommutative spectral flow for paths of regular selfadjoint Fredholm operators on a countably generated Hilbert C*-module. We give an axiomatic description and discuss some applications. One of them is the definition of a noncommutative Maslov index for paths of Lagrangians which appears in a splitting formula for the spectral flow. Analogously we study the spectral flow for odd operators on a graded module.

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Charlotte Wahl. 2007-07-21. On the noncommutative spectral flow. https://arxiv.org/abs/math/0602110

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