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arXiv · 2404.04563

Multiplicatively spectrum-preserving maps on $C^{*}$-algebras

Michiya Mori·Shiho Oi
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Abstract

We study surjective maps between the sets of all self-adjoint elements of unital $C^*$-algebras which satisfy the multiplicatively spectrum-preserving property. We show that such maps are characterized by Jordan isomorphisms and central symmetries. This is an answer to a problem posed by Moln\'ar.

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Michiya Mori, Shiho Oi. 2024-04-06. Multiplicatively spectrum-preserving maps on $C^{*}$-algebras. https://arxiv.org/abs/2404.04563

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