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arXiv · 2605.08096

Additive preservers of mutual strong Birkhoff-James orthogonality on finite-dimensional $C^\ast$-algebras

Bojan Kuzma·Srdjan Stefanović
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Abstract

We describe additive surjections on direct sum of matrix algebras that preserve singularity in one direction. As an application, we classify additive surjections on finite-dimensional $C^\ast$-algebras that preserve mutual strong Birkhoff-James orthogonality in one direction.

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Bojan Kuzma, Srdjan Stefanović. 2026-04-14. Additive preservers of mutual strong Birkhoff-James orthogonality on finite-dimensional $C^\ast$-algebras. https://arxiv.org/abs/2605.08096

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