DOI

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.

Язык оригиналаанглийский
Страницы (с-по)249-263
Число страниц15
ЖурналFunctional Analysis and its Applications
Том40
Номер выпуска4
DOI
СостояниеОпубликовано - 1 окт 2006

    Предметные области Scopus

  • Анализ
  • Прикладная математика

ID: 51700815