On an extension of norms from a subspace to the whole Banach space keeping their rotundity

M. Fabian

ArticleOriginal scientific text

Title

On an extension of norms from a subspace to the whole Banach space keeping their rotundity

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Affiliations

Institute of Mathematics, Academy of Sciences of the Czech Republic, Žitná 25, 115 67 Praha 1, Czech Republic

Abstract

Let ℛ denote some kind of rotundity, e.g., the uniform rotundity. Let X admit an ℛ-norm and let Y be a reflexive subspace of X with some ℛ-norm ∥·∥. Then we are able to extend ∥·∥ from Y to an ℛ-norm on X.

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Title

On an extension of norms from a subspace to the whole Banach space keeping their rotundity

Affiliations

Abstract

Bibliography