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arXiv · 1510.05308

Essential Spectrum and Fredholm Properties for Operators on Locally Compact Groups

Marius Mantoiu
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Abstract

We study the essential spectrum and Fredholm properties of integral and pseudodiferential operators associated to (maybe non-commutative) locally compact groups G. The techniques involve crossed product C*-algebras. We extend previous results on the structure of the essential spectrum to operators belonging (or affiliated) to the Schrödinger representation of certain crossed products. When the group G is unimodular and type I, we cover a new class of pseudo-differential differential operators with operator-valued symbols involving the unitary dual of G. We use recent results on the role of families of representations in spectral theory and the notion of quasi-regular dynamical system.

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Marius Mantoiu. 2015-10-18. Essential Spectrum and Fredholm Properties for Operators on Locally Compact Groups. https://arxiv.org/abs/1510.05308

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