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arXiv · 2512.03956

Morita equivalence and stable isomorphism via unitary operators

Nikolaos Koutsonikos-Kouloumpis
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Abstract

We define $\Delta$-equivalence for dual operator systems and prove that it is an equivalence relation. We show that weak TRO-equivalence of dual operator spaces induces a stable isomorphism between them which is given by multiplication with unitary operators, and in the special case of dual operator systems it is a unitary equivalence. We prove an analogous result for strong TRO-equivalence of operator spaces and for operator systems. Lastly, we show that $\Delta$-equivalent dual operator spaces, considered as bimodules over their left and right adjointable multiplier algebras, have TRO-equivalent normal CES representations.

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Nikolaos Koutsonikos-Kouloumpis. 2025-12-03. Morita equivalence and stable isomorphism via unitary operators. https://arxiv.org/abs/2512.03956

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