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arXiv · 1812.00167

The operator--valued parallelism and norm-parallelism in matrices

M. Mohammadi Gohari·M. Amyari
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Abstract

Let $\mathcal{H}$ be a Hilbert space, and let $K(\mathcal{H})$ be the $C^*$-algebra of compact operators on $\mathcal{H}$. In this paper, we present some characterizations of the norm-parallelism for elements of a Hilbert $K(\mathcal{H})$-module by employing the Birkhoff--James orthogonality. Among other things, we present a characterization of transitive relation of the norm-parallelism for elements in a certain Hilbert $K(\mathcal{H})$-module. We also give some characterizations of the Schatten $p$-norms and the operator norm-parallelism for matrices.

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M. Mohammadi Gohari, M. Amyari. 2018-12-01. The operator--valued parallelism and norm-parallelism in matrices. https://arxiv.org/abs/1812.00167

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