Annals of Functional Analysis

Geometric constants of π/2-rotation invariant norms on R2

Yukino Tomizawa, Ken-Ichi Mitani, Kichi-Suke Saito, and Ryotaro Tanaka

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Abstract

In this article, we study the (modified) von Neumann–Jordan constant and Zbăganu constant of π/2-rotation invariant norms on R2. Some estimations of these geometric constants are given. As an application, we construct various examples consisting of π/2-rotation invariant norms.

Article information

Source
Ann. Funct. Anal., Volume 8, Number 2 (2017), 215-230.

Dates
Received: 8 May 2016
Accepted: 25 August 2016
First available in Project Euclid: 31 January 2017

Permanent link to this document
https://projecteuclid.org/euclid.afa/1485831764

Digital Object Identifier
doi:10.1215/20088752-0000007X

Mathematical Reviews number (MathSciNet)
MR3603777

Zentralblatt MATH identifier
1378.46016

Subjects
Primary: 46B20: Geometry and structure of normed linear spaces

Keywords
(modified) von Neumann–Jordan constant Zbăganu constant rotation invariant norm

Citation

Tomizawa, Yukino; Mitani, Ken-Ichi; Saito, Kichi-Suke; Tanaka, Ryotaro. Geometric constants of $\pi/2$ -rotation invariant norms on $\mathbb{R}^{2}$. Ann. Funct. Anal. 8 (2017), no. 2, 215--230. doi:10.1215/20088752-0000007X. https://projecteuclid.org/euclid.afa/1485831764


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