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arXiv · 2412.07137

The ball-covering property of non-commutative spaces of operators on Banach spaces

Qiyao Bao·Rui Liu·Jie Shen
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Abstract

A Banach space is said to have the ball-covering property (BCP) if its unit sphere can be covered by countably many closed or open balls off the origin. Let $X$ be a Banach space with a shrinking $1$-unconditional basis. In this paper, by constructing an equivalent norm on $B(X)$, we prove that the quotient Banach algebra $B(X)/K(X)$ fails the BCP. In particular, the result implies that the Calkin algebra $B(H)/ K(H)$, $B(\ell^p)/K(\ell^p)$ ($1 \leq p <\infty$) and $B(c_0)/K(c_0)$ all fail the BCP. We also show that $B(L^p[0,1])$ has the uniform ball-covering property (UBCP) for $3/2< p < 3$.

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Qiyao Bao, Rui Liu, Jie Shen. 2024-12-10. The ball-covering property of non-commutative spaces of operators on Banach spaces. https://arxiv.org/abs/2412.07137

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