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Characterisations of orthogonality in certain Banach spaces. (English) Zbl 1006.46022

Summary: We adopt the notion of orthogonality introduced by the author in a previous article. We establish a characterization for orthogonality in the spaces \(\ell^p_S(\mathbb{C})\), \(1\leq p<\infty\), where \(S\) is a set of positive integers and \(\mathbb{C}\) is the field of complex numbers. Generalizations of the usual characterization of orthogonality in the Hilbert spaces \(\ell^2_S(\mathbb{C})\), via inner products, are obtained.

MSC:

46C50 Generalizations of inner products (semi-inner products, partial inner products, etc.)
46B20 Geometry and structure of normed linear spaces
46B45 Banach sequence spaces
Full Text: DOI

References:

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