Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria.
Vienna Center for Quantum Science & Technology (VCQ), Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
Phys Rev Lett. 2018 Aug 24;121(8):080403. doi: 10.1103/PhysRevLett.121.080403.
In this Letter, we present a cosmic Bell experiment with polarization-entangled photons, in which measurement settings were determined based on real-time measurements of the wavelength of photons from high-redshift quasars, whose light was emitted billions of years ago; the experiment simultaneously ensures locality. Assuming fair sampling for all detected photons and that the wavelength of the quasar photons had not been selectively altered or previewed between emission and detection, we observe statistically significant violation of Bell's inequality by 9.3 standard deviations, corresponding to an estimated p value of ≲7.4×10^{-21}. This experiment pushes back to at least ∼7.8 Gyr ago the most recent time by which any local-realist influences could have exploited the "freedom-of-choice" loophole to engineer the observed Bell violation, excluding any such mechanism from 96% of the space-time volume of the past light cone of our experiment, extending from the big bang to today.
在这封信件中，我们提出了一个基于偏振纠缠光子的宇宙贝尔实验，其中测量设置是根据来自高红移类星体的光子波长的实时测量来确定的，这些光子的光在数十亿年前就已经发出；实验同时保证了局域性。假设所有探测到的光子都进行了公平抽样，并且在发射和探测之间，类星体光子的波长没有被选择性地改变或预先设定，那么我们观察到贝尔不等式以 9.3 个标准差显著违反，对应的 p 值估计约为 ≲7.4×10^{-21}。这个实验将任何局域实在论影响能够利用“自由选择”漏洞来设计观察到的贝尔违反的最近时间至少推回到 7.8 Gyr 之前，排除了我们实验过去光锥的 96%的时空体积中的任何这样的机制，从大爆炸延伸到今天。
