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Positivity of Lyapunov exponents for a continuous matrix-valued Anderson model

H. Boumaza
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Abstract

We study a continuous matrix-valued Anderson-type model. Both leading Lyapunov exponents of this model are proved to be positive and distinct for all ernergies in $(2,+\infty)$ except those in a discrete set, which leads to absence of absolutely continuous spectrum in $(2,+\infty)$. This result is an improvement of a previous result with Stolz. The methods, based upon a result by Breuillard and Gelander on dense subgroups in semisimple Lie groups, and a criterion by Goldsheid and Margulis, allow for singular Bernoulli distributions.

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H. Boumaza. 2007-03-20. Positivity of Lyapunov exponents for a continuous matrix-valued Anderson model. https://doi.org/10.1007/s11040-007-9023-6

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