Random number generation with cosmic photons

Understand

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.