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arXiv · 2507.12810

On extreme points of the unit ball of a Hardy-Lorentz space

Sergey V. Astashkin
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Abstract

We investigate the problem of a characterization of extreme points of the unit ball of a Hardy-Lorentz space $H(\Lambda(\varphi))$, posed by Semenov in 1978. New necessary and sufficient conditions, under which a normalized function $f$ in $H(\Lambda(\varphi))$ 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.

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Sergey V. Astashkin. 2025-07-17. On extreme points of the unit ball of a Hardy-Lorentz space. https://arxiv.org/abs/2507.12810

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