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arXiv · 1106.6097

Continuity of the Lyapunov Exponent for analytic quasi-perodic cocycles with singularities

S. Jitomirskaya·C. A. Marx
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Abstract

We prove that the Lyapunov exponent of quasi-periodic cocyles with singularities behaves continuously over the analytic category. We thereby generalize earlier results, where singularities were either excluded completely or constrained by additional hypotheses. Applications are one-parameter families of analytic Jacobi operators, such as extended Harper's model describing crystals subject to external magnetic fields.

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S. Jitomirskaya, C. A. Marx. 2011-06-30. Continuity of the Lyapunov Exponent for analytic quasi-perodic cocycles with singularities. https://doi.org/10.1007/s11784-011-0055-y

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