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Quantum Mechanics Based on Real Numbers: A Consistent Description
Pedro Barrios Hita1,2, Anton Trushechkin2, Hermann Kampermann2
1German Aerospace Center (DLR), Institute of Software Technology, Sankt Augustin, Germany.
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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