Random numbers are indispensable for a variety of applications ranging from testing physics foundation to information encryption. In particular, nonlocality tests provide a strong evidence to our current understanding of nature -- quantum mechanics. All the random number generators (RNG) used for the existing tests are constructed locally, making the test results vulnerable to the freedom-of-choice loophole. We report an experimental realization of RNGs based on the arrival time of cosmic photons. The measurement outcomes (raw data) pass the standard NIST statistical test suite. We present a realistic design to employ these RNGs in a Bell test experiment, which addresses the freedom-of-choice loophole.
@article{arxiv.1611.07126,
title = {Random number generation with cosmic photons},
author = {Cheng Wu and Bing Bai and Yang Liu and Xiaoming Zhang and Meng Yang and Yuan Cao and Jianfeng Wang and Shaohua Zhang and Hongyan Zhou and Xiheng Shi and Xiongfeng Ma and Ji-Gang Ren and Jun Zhang and Cheng-Zhi Peng and Jingyun Fan and Qiang Zhang and Jian-Wei Pan},
journal= {arXiv preprint arXiv:1611.07126},
year = {2017}
}