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arXiv · 2509.26066

An $\ell^1$-Isometric Subspace of $C[0,1]$ with Countable Oscillating Spectrum

Geivison Ribeiro
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Abstract

In this paper we construct a closed subspace $X\subset C[0,1]$ with countable oscillating spectrum $\Omega(X)$ such that $X$ is isometric to $\ell^1$. This provides a negative answer to Question~4.3 posed by Enflo, Gurariy, and Seoane in [Trans. Amer. Math. Soc. \textbf{366} (2014)].

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Geivison Ribeiro. 2025-09-30. An $\ell^1$-Isometric Subspace of $C[0,1]$ with Countable Oscillating Spectrum. https://arxiv.org/abs/2509.26066

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