Stability of the ball-covering property
Abstract
A normed space X is said to have the ball-covering property (BCP, for short) if its unit sphere can be covered by the union of countably many closed balls not containing the origin. Let (Ω, Σ, µ) be a separable measure space and X be a normed space. We show that Lp(µ, X) (1 ≤ p < ∞) has the BCP if and only if X has the BCP. We also prove that if {Xk} is a sequence of normed spaces, then X = (Σ ⊕ Xk)p has the BCP if and only each Xk has the BCP, where 1 ≤ p ≤ ∞. However, it is shown that L∞[0, 1] fails the BCP.
Publication Title
Studia Mathematica
Recommended Citation
Luo, Z., & Zheng, B. (2020). Stability of the ball-covering property. Studia Mathematica, 250 (1), 19-34. https://doi.org/10.4064/sm180607-6-10