Absolute normalized norms in \(\mathbb R^2\) and Heinz means constant. (English) Zbl 1518.46008

Summary: In this paper, we calculate the precise values of the Heinz means constant under the absolute normalized norms in \(\mathbb{R}^2\). The conclusions do not only contain some previous results, but also give the exact values of the Heinz means constant for some new concrete Banach spaces.


46B20 Geometry and structure of normed linear spaces
46B25 Classical Banach spaces in the general theory
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