Almost periodic Szego cocycles with uniformly positive Lyapunov exponents
نویسندگان
چکیده
We exhibit examples of almost periodic Verblunsky coefficients for which Herman’s subharmonicity argument applies and yields that the associated Lyapunov exponents are uniformly bounded away from zero. As an immediate consequence of this result, we obtain examples of almost periodic Verblunsky coefficients for which the associated probability measure on the unit circle is pure point.
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ورودعنوان ژورنال:
- Journal of Approximation Theory
دوره 161 شماره
صفحات -
تاریخ انتشار 2009