Sufficient Conditions for Synthesability of Exponential Systems

The study considers the sufficient conditions for synthesability of exponential systems {e^iλt}_λ∈Λ in L²(-π, π) in terms of generating function G = G_Λ. The obtained results are of interest not only for the theory of functions but also for the theory of operators, since the synthesizability of ε(Λ) systems corresponds to the synthesizability of special perturbations of the level one of self-adjoint operators

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