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Some new estimates on the spectral shift function associated with random Schrödinger operators

Jean-Michel Combes·Peter Hislop·Frédéric Klopp
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Abstract

We prove some new pointwise-in-energy bounds on the expectations of various spectral shift functions associated with random Schrödinger operators in the continuum having Anderson-type random potentials in both finite-volume and infinite-volume. These estimates are a consequence of our new Wegner estimate for finite-volume random Schrödinger operators. For lattice models, we also obtain a representation of the infinite-volume density of states in terms of a spectral shift function. For continuum models, the corresponding measure is absolutely continuous with respect to the density of states and agrees with it in certain cases. We present a variant of a new spectral averaging result and use it to prove a pointwise upper bound on the SSF for finite-rank perturbations.

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Jean-Michel Combes, Peter Hislop, Frédéric Klopp. 2006-10-14. Some new estimates on the spectral shift function associated with random Schrödinger operators. https://arxiv.org/abs/math-ph/0605030

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