The non-local correlations exhibited when measuring entangled particles can be used to certify the presence of genuine randomness in Bell experiments. While non-locality is necessary for randomness certification, it is unclear when and why non-locality certifies maximal randomness. We provide here a simple argument to certify the presence of maximal local and global randomness based on symmetries of a Bell inequality and the existence of a unique quantum probability distribution that maximally violates it. Using our findings, we prove the existence of N-party Bell test attaining maximal global randomness, that is, where a combination of measurements by each party provides N perfect random bits.
@article{arxiv.1211.0650,
title = {Maximal quantum randomness in Bell tests},
author = {Chirag Dhara and Giuseppe Prettico and Antonio Acin},
journal= {arXiv preprint arXiv:1211.0650},
year = {2013}
}