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ON SOME CLASS OF EXTREME POINTS OF THE UNIT BALL OF A HARDY-LORENTZ SPACE
- Authors: Astashkin S.V.1,2,3
-
Affiliations:
- Samara National Research University
- Lomonosov Moscow State University, Moscow Сenter of Fundamental and Applied Mathematics
- Bahcesehir University
- Issue: Vol 522, No 1 (2025)
- Pages: 3-6
- Section: MATHEMATICS
- URL: https://jdigitaldiagnostics.com/2686-9543/article/view/683767
- DOI: https://doi.org/10.31857/S2686954325020016
- EDN: https://elibrary.ru/HYWTQE
- ID: 683767
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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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