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arXiv · 2504.07808

Locality Implies Complex Numbers in Quantum Mechanics

Tianfeng Feng·Changliang Ren·Vlatko Vedral
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Abstract

We show that the presented real-number quantum theories, compatible with the independent source assumption, require the inclusion of a nonlocal map. This means that if the independent source assumption holds, in these models, complex-number quantum theory is equivalent to a real-number quantum theory with hidden nonlocal degrees of freedom. Our results suggest that complex numbers may be indispensable for describing the process involving entanglement between two independent systems.

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Tianfeng Feng, Changliang Ren, Vlatko Vedral. 2025-04-10. Locality Implies Complex Numbers in Quantum Mechanics. https://arxiv.org/abs/2504.07808

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