Saved in:
Bibliographic Details
Main Authors: Enami, Yuta, Matsuzaki, Izuho
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2603.00583
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912934287900672
author Enami, Yuta
Matsuzaki, Izuho
author_facet Enami, Yuta
Matsuzaki, Izuho
contents For a locally compact Hausdorff space $L$, we denote by $C_0(L,\mathbb{R})$ the Banach space of all continuous real-valued functions on $L$ vanishing at infinity, endowed with the supremum norm. In this paper, we prove that every surjective phase-isometry $T\colon S(C_0(X,\mathbb{R}))\to S(C_0(Y,\mathbb{R}))$ between the unit spheres of $C_0(X,\mathbb{R})$ and $C_0(Y,\mathbb{R})$ is a variant of a weighted composition operator in the following sense: there exist a function $\varepsilon\colon S(C_0(X,\mathbb{R}))\to\{-1,1\}$,a continuous function $α\colon Y\to \{-1,1\}$ and a homeomorphism $σ\colon Y\to X$ such that $T(f)(q)=\varepsilon(f)α(q)f(σ(q))$ for every $f\in S(C_0(X,\mathbb{R}))$ and $q\in Y$.
format Preprint
id arxiv_https___arxiv_org_abs_2603_00583
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle On phase-isometries between the unit spheres of the Banach space of continuous real-valued functions
Enami, Yuta
Matsuzaki, Izuho
Functional Analysis
For a locally compact Hausdorff space $L$, we denote by $C_0(L,\mathbb{R})$ the Banach space of all continuous real-valued functions on $L$ vanishing at infinity, endowed with the supremum norm. In this paper, we prove that every surjective phase-isometry $T\colon S(C_0(X,\mathbb{R}))\to S(C_0(Y,\mathbb{R}))$ between the unit spheres of $C_0(X,\mathbb{R})$ and $C_0(Y,\mathbb{R})$ is a variant of a weighted composition operator in the following sense: there exist a function $\varepsilon\colon S(C_0(X,\mathbb{R}))\to\{-1,1\}$,a continuous function $α\colon Y\to \{-1,1\}$ and a homeomorphism $σ\colon Y\to X$ such that $T(f)(q)=\varepsilon(f)α(q)f(σ(q))$ for every $f\in S(C_0(X,\mathbb{R}))$ and $q\in Y$.
title On phase-isometries between the unit spheres of the Banach space of continuous real-valued functions
topic Functional Analysis
url https://arxiv.org/abs/2603.00583