Let Θ be an inner function in the upper half-plane ℂ+ and let K Θ denote the model subspace H 2 θ Θ H 2 of the Hardy space H 2 = H 2(ℂ+). A nonnegative function w on the real line is said to be an admissible majorant for K Θ if there exists a nonzero function f K Θ such that f ≤ w a.e. on ℝ. We prove a refined version of the parametrization formula for K Θ-admissible majorants and simplify the admissibility criterion (in terms of arg Θ) obtained in [8]. We show that, for every inner function Θ, there exist minimal K Θ-admissible majorants. The relationship between admissibility and some weighted approximation problems is considered.

Original languageEnglish
Pages (from-to)249-263
Number of pages15
JournalFunctional Analysis and its Applications
Volume40
Issue number4
DOIs
StatePublished - 1 Oct 2006

    Research areas

  • Beurling-Malliavin theorem, Entire function, Hardy space, Inner function, Model subspace

    Scopus subject areas

  • Analysis
  • Applied Mathematics

ID: 51700815