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

Radyna, Yauhen; Radyno, Yakov; Sidorik, Anna

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

Authors

Radyna, Yauhen

Radyno, Yakov

Sidorik, Anna

Description

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.
6 pages, translation to English