English

On the Kunz-Souillard approach to localization for the discrete one dimensional generalized Anderson model

Spectral Theory 2016-10-26 v2 Mathematical Physics math.MP

Abstract

We prove dynamical and spectral localization at all energies for the discrete generalized Anderson model via the Kunz-Souillard approach to localization. This is an extension of the original Kunz-Souillard approach to localization for Schr\"odinger operators, to the case where a single random variable determines the potential on a block of an arbitrary, but fixed, size α\alpha. For this model, we also give a description of the almost sure spectrum as a set and prove uniform positivity of the Lyapunov exponents. In fact, regarding positivity of the Lyapunov exponents, we prove a stronger statement where we also allow finitely supported distributions. We also show that for any size α\alpha {\it generalized Anderson model}, there exists some finitely supported distribution ν\nu for which the Lyapunov exponent will vanish for at least one energy. Moreover, restricting to the special case α=1\alpha=1, we describe a pleasant consequence of this modified technique to the original Kunz-Souillard approach to localization. In particular, we demonstrate that actually the single operator T1T_1 is a strict contraction in L2(R)L^2(\mathbb{R}), whereas before it was only shown that the second iterate of T1T_1 is a strict contraction.

Keywords

Cite

@article{arxiv.1608.01379,
  title  = {On the Kunz-Souillard approach to localization for the discrete one dimensional generalized Anderson model},
  author = {Valmir Bucaj},
  journal= {arXiv preprint arXiv:1608.01379},
  year   = {2016}
}

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47 pages