Li Zheng-Da, Mao Ya-Li, Weilenmann Mirjam, Tavakoli Armin, Chen Hu, Feng Lixin, Yang Sheng-Jun, Renou Marc-Olivier, Trillo David, Le Thinh P, Gisin Nicolas, Acín Antonio, Navascués Miguel, Wang Zizhu, Fan Jingyun
Shenzhen Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China.
Guangdong Provincial Key Laboratory of Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Phys Rev Lett. 2022 Jan 28;128(4):040402. doi: 10.1103/PhysRevLett.128.040402.
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 pioneering days. Recently it has been shown that tests in the spirit of a Bell inequality can reveal quantum predictions in entanglement swapping scenarios that cannot be modeled by the natural real-number analog of standard quantum theory. Here, we tailor such tests for implementation in state-of-the-art photonic systems. We experimentally demonstrate quantum correlations in a network of three parties and two independent EPR sources that violate the constraints of real quantum theory by over 4.5 standard deviations, hence disproving real quantum theory as a universal physical theory.
量子理论通常在复希尔伯特空间中表述。然而，自其开创以来，复数是否需要在该理论中扮演基本角色的问题就一直存在争议。最近有研究表明，符合贝尔不等式精神的测试能够揭示纠缠交换场景中的量子预测，而这是标准量子理论的自然实数类比所无法模拟的。在此，我们对这类测试进行调整，以便在最先进的光子系统中实施。我们通过实验证明了三方和两个独立EPR源网络中的量子关联，该关联违反了实量子理论的约束超过4.5个标准差，从而证明实量子理论并非普遍适用的物理理论。
