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arXiv · 1912.03635

Birkhoff-James orthogonality to a subspace of operators defined between Banach spaces

Arpita Mal·Kallol Paul
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Abstract

This paper deals with study of Birkhoff-James orthogonality of a linear operator to a subspace of operators defined between arbitrary Banach spaces. In case the domain space is reflexive and the subspace is finite dimensional we obtain a complete characterization. For arbitrary Banach spaces, we obtain the same under some additional conditions. For arbitrary Hilbert space $ \mathbb{H},$ we also study orthogonality to subspace of the space of linear operators $L(\mathbb{H}), $ both with respect to operator norm as well as numerical radius norm.

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Arpita Mal, Kallol Paul. 2019-12-08. Birkhoff-James orthogonality to a subspace of operators defined between Banach spaces. https://arxiv.org/abs/1912.03635

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