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arXiv · 2607.13915

Invariance Preserving Conjugations on the Hardy Space

Arup Chattopadhyay·Supratim Jana
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Abstract

We obtain a complete characterization of the class of conjugation operators $C$ on $H^2$ that map shift-invariant subspaces to shift-invariant subspaces. Alongside, we also obtain the existence and non-existence of conjugations that send shift-invariant subspaces to coinvariant subspaces.

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Arup Chattopadhyay, Supratim Jana. 2026-07-15. Invariance Preserving Conjugations on the Hardy Space. https://arxiv.org/abs/2607.13915

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