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arXiv · 2610.06728

Failure of Nehari's Theorem for Multiplicative Hankel Forms in Schatten Classes II

Konstantinos Bampouras
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Abstract

We prove that for any $p>4$ we can find a Schatten class Hankel operator $\Ha_ϕ$ defined on the Hardy space of the infinite torus $H^2(\mathbb{T}^\infty)$ that belongs to the Schatten class $S^p$ but does not admit a bounded symbol, extending the previously known range $p>(1-\logπ/\log 4)^{-1}=5.7388...$.

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Konstantinos Bampouras. 2026-10-05. Failure of Nehari's Theorem for Multiplicative Hankel Forms in Schatten Classes II. https://arxiv.org/abs/2610.06728

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