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arXiv · 0803.3646

Characterizing Hilbert spaces using Fourier transform over the field of p-adic numbers

Yauhen Radyna·Yakov Radyno·Anna Sidorik
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Abstract

We characterize Hilbert spaces in the class of all Banach spaces using Fourier transform of vector-valued functions over the field $Q_p$ of $p$-adic numbers. Precisely, Banach space $X$ is isomorphic to a Hilbert one if and only if Fourier transform $F: L_2(Q_p,X)\to L_2(Q_p,X)$ in space of functions, which are square-integrable in Bochner sense and take value in $X$, is a bounded operator.

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Yauhen Radyna, Yakov Radyno, Anna Sidorik. 2008-03-25. Characterizing Hilbert spaces using Fourier transform over the field of p-adic numbers. https://arxiv.org/abs/0803.3646

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