Polya Sequences, Toeplitz Kernels and Gap Theorems
نویسنده
چکیده
A separated sequence Λ on the real line is called a Polya sequence if any entire function of zero exponential type bounded on Λ is constant. In this paper we solve the problem by Polya and Levinson that asks for a description of Polya sets. We also show that the Polya-Levinson problem is equivalent to a version of the so-called Beurling gap problem on Fourier transforms of measures. The solution is obtained via a recently developed approach based on the use of Toeplitz kernels and de Branges spaces of entire functions.
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