Annals of Functional Analysis

Wide and tight spherical hulls of bounded sets in Banach spaces

Abstract

Let $A$ be a bounded closed convex set in a Banach space. The boundaries of the wide spherical hull $\eta (A)$ and the tight spherical hull $\theta (A)$ are characterized, the existence of diametral points of these three sets are discussed, and a further relation between these three sets is clarified. Moreover, a new characterization of balls is presented.

Article information

Source
Ann. Funct. Anal., Volume 7, Number 2 (2016), 290-302.

Dates
Accepted: 4 August 2015
First available in Project Euclid: 21 March 2016

https://projecteuclid.org/euclid.afa/1458580169

Digital Object Identifier
doi:10.1215/20088752-3505890

Mathematical Reviews number (MathSciNet)
MR3476639

Zentralblatt MATH identifier
1373.46009

Citation

He, Chan; Wu, Senlin; Zhang, Xinling. Wide and tight spherical hulls of bounded sets in Banach spaces. Ann. Funct. Anal. 7 (2016), no. 2, 290--302. doi:10.1215/20088752-3505890. https://projecteuclid.org/euclid.afa/1458580169

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