Beurling-malliavin Theory for Toeplitz Kernels
نویسنده
چکیده
We consider the family of Toeplitz operators TJS̄a acting in the Hardy space H in the upper halfplane; J and S are given meromorphic inner functions, and a is a real parameter. In the case where the argument of S has a power law type behavior on the real line, we compute the critical value c(J, S) = inf {a : ker TJS̄a 6= 0} . The formula for c(J, S) generalizes the Beurling-Malliavin theorem on the radius of completeness for a system of exponentials.
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تاریخ انتشار 2008