ON SOME CLASS OF EXTREME POINTS OF THE UNIT BALL OF A HARDY-LORENTZ SPACE

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Abstract

The problem of a characterization of the set of extreme points of the unit ball in the Hardy-Lorentz space H(Λ(φ)), posed by E.M. Semenov in 1978, is considered. New necessary and sufficient conditions, under which a normalized function f in H(Λ(φ)) belongs to this set, are found. The most complete results are obtained in the case when f is the product of an outer analytic function and a Blaschke factor.

About the authors

S. V. Astashkin

Samara National Research University; Lomonosov Moscow State University, Moscow Сenter of Fundamental and Applied Mathematics; Bahcesehir University

Email: astash@ssau.ru
Moscow, Russia; Moscow, Russia; Istanbul, Turkey

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