Quantum Random Numbers: A Survey on Sources, Numerical Evidence, and Applications in Security and Computing

Random numbers are used to generate cryptographic keys, to run Monte Carlo simulations, and to train and sample machine learning models. Most software obtains them from deterministic pseudo-random number generators, which have good statistical properties but are predictable once their internal state is known. Quantum random number generators take their output from measurements on quantum systems, whose outcomes are not fixed by any prior state of the device. This article introduces the types of random number generators, reviews studies that compare quantum and pseudo-random numbers in numerical experiments, and lists the sources of randomness available in current computing systems. It then describes applications of quantum randomness in security, hashing, software, artificial intelligence, and public randomness. The quality of encryption is treated as depending on three factors: the algorithm, its implementation, and the randomness of keys and other security-relevant values. We give arguments for which applications benefit from quantum randomness, name further areas in which it could be tested, and outline next steps.