# Quantum theory based on real numbers can be experimentally falsified.

@article{Renou2021QuantumTB, title={Quantum theory based on real numbers can be experimentally falsified.}, author={Marc-Olivier Renou and David Trillo and Mirjam Weilenmann and Thinh P Le and Armin Tavakoli and Nicolas Gisin and Antonio Ac{\'i}n and Miguel Navascu{\'e}s}, journal={Nature}, year={2021} }

Although complex numbers are essential in mathematics, they are not needed to describe physical experiments, as those are expressed in terms of probabilities, hence real numbers. Physics, however, aims to explain, rather than describe, experiments through theories. Although most theories of physics are based on real numbers, quantum theory was the first to be formulated in terms of operators acting on complex Hilbert spaces1,2. This has puzzled countless physicists, including the fathers of the…

## 16 Citations

Ruling Out Real-Valued Standard Formalism of Quantum Theory.

- EducationPhysical review letters
- 2022

Standard quantum theory was formulated with complex-valued Schrödinger equations, wave functions, operators, and Hilbert spaces. Previous work attempted to simulate quantum systems using only real…

QuantumMechanics Must Be Complex Two independent studies demonstrate that a formulation of quantum mechanics involving complex rather than real numbers is necessary to reproduce experimental results

- Physics
- 2022

Figure 1: Conceptual sketch of the three-party game used by Chen and colleagues and Li and colleagues to demonstrate that a real quantum theory cannot describe certain measurements on small quantum…

Testing Real Quantum Theory in an Optical Quantum Network.

- PhysicsPhysical review letters
- 2022

Quantum theory is commonly formulated in complex Hilbert spaces. However, the question of whether complex numbers need to be given a fundamental role in the theory has been debated since its…

Nonlocality for Generic Networks.

- MathematicsPhysical review letters
- 2022

Bell's theorem shows that correlations created by a single entangled quantum state cannot be reproduced classically. Such correlations are called nonlocal. They are the elementary manifestation of a…

Network nonlocality via rigidity of token counting and color matching

- Computer SciencePhysical Review A
- 2022

This paper introduces two families of strategies to produce nonlocal correlations in networks and shows that TC and CM distributions are rigidity in wide classes of networks, meaning that there is essentially a unique classical strategy to simulate such correlations.

Full Network Nonlocality.

- Computer SciencePhysical review letters
- 2022

It is pointed out that established methods for analyzing local and theory-independent correlations in networks can be combined in order to systematically deduce sufficient conditions for full network nonlocality in any network and input-output scenario, and it is shown that these inequalities can be violated via quantum elegant joint measurements.

Source-independent quantum random number generator against detector blinding attacks

- Physics, Materials ScienceArXiv
- 2022

Randomness, mainly in the form of random numbers, is the fundamental prerequisite for the security of many cryptographic tasks. Quantum randomness can be extracted even if adversaries are fully aware…

Does quantum mechanics need imaginary numbers?

- PhysicsPhysics Today
- 2022

A newly proposed experiment rules out a class of real-valued quantum theories.

Quantum networks self-test all entangled states

- History
- 2022

Ivan Šupić,1 Joseph Bowles,2 Marc-Olivier Renou,2 Antonio Acín,2, 3 and Matty J. Hoban4, 5 CNRS, LIP6, Sorbonne Université, 4 place Jussieu, 75005 Paris, France ICFO-Institut de Ciencies Fotoniques,…

Recycling nonlocality in a quantum network

- Physics
- 2022

Ya-Li Mao,1, 2, ∗ Zheng-Da Li,1, 2, ∗ Anna Steffinlongo,3, 4, 5 Bixiang Guo,1, 2 Biyao Liu,1, 2 Shufeng Xu,1, 2 Nicolas Gisin,6, 7, † Armin Tavakoli,4, 5, ‡ and Jingyun Fan1, 2, § Shenzhen Institute…

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