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arXiv · 2603.29103

Extreme points in quotients of Hardy spaces

Konstantin M. Dyakonov
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Abstract

In the Hardy spaces $H^1$ and $H^\infty$, there are neat and well-known characterizations of the extreme points of the unit ball. We obtain counterparts of these classical theorems when $H^1$ (resp., $H^\infty$) gets replaced by the quotient space $H^1/E$ (resp., $H^\infty/E$), under certain assumptions on the subspace $E$. In the $H^1$ setting, we also treat the case where the underlying space is taken to be the kernel of a Toeplitz operator.

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Konstantin M. Dyakonov. 2026-03-31. Extreme points in quotients of Hardy spaces. https://arxiv.org/abs/2603.29103

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