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arXiv · 2503.17307

Quantum mechanics based on real numbers: A consistent description

Pedro Barrios Hita·Anton Trushechkin·Hermann Kampermann·Michael Epping·Dagmar Bruß
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Abstract

Complex numbers play a crucial role in quantum mechanics. However, their necessity remains debated: whether they are fundamental or merely convenient. Recently, it was shown that any real-number quantum theory satisfying certain postulates can be falsified with multipartite experiments. In this Letter we show that a physically motivated postulate about composite quantum systems allows us to construct quantum mechanics based on real numbers that reproduces predictions for all multipartite quantum experiments. Thus, we argue that real-valued quantum mechanics cannot be falsified, and therefore the use of complex numbers is a matter of convenience.

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Pedro Barrios Hita, Anton Trushechkin, Hermann Kampermann, Michael Epping, Dagmar Bruß. 2025-03-21. Quantum mechanics based on real numbers: A consistent description. https://doi.org/10.1103/4k13-sdjh

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