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arXiv · 2101.11561

When Kalton and Peck met Fourier

Félix Cabello Sánchez·Alberto Salguero-Alarcón
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Abstract

The paper studies short exact sequences of Banach modules over the convolution algebra $L_1=L_1(G)$, where $G$ is a compact abelian group. The main tool is the notion of a nonlinear $L_1$-centralizer, which in combination with the Fourier transform, is used to produce sequences of $L_1$-modules $0\rightarrow L_q \rightarrow Z \rightarrow L_p \rightarrow 0$ that are nontrivial as long as the general theory allows it, namely for $p\in (1,\infty], q\in[1,\infty)$. Concrete examples are worked in detail for the circle group, with applications to the Hardy classes, and the Cantor group.

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Félix Cabello Sánchez, Alberto Salguero-Alarcón. 2021-01-27. When Kalton and Peck met Fourier. https://arxiv.org/abs/2101.11561

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