Speaker: Serge Massar, Université Libre de Bruxelles, Belgium
Abstract: Randomness is a physical phenomena which we are confronted with all the time. Will it rain today? At what time? Will the train be on time? But are such phenomena truly random? Good randomness is essential for many applications. Cryptography, the art of hiding information from malicious users, is only as good as the source of randomness that underlies it. Quantum mechanics, the theory of microscopic phenomena, can only predict the probability of events: for instance quantum theory can only predict the probability that a radioactive nucleus will decay, not if the nucleus will decay. Does this mean that microscopic phenomena are truly random? By studying systems of two entangled particles, it can be shown both theoretically and experimentally, that events at the microscopic scale are truly random, truly unpredictable. Beyond its philosophical implications, these works also have important potential applications. Indeed they imply that one can build random number generators that certify that they work correctly. That is, if the random number generator malfunctions in some way, if the numbers it produces cease to be random, this will automatically be detected. By extending this idea, one could also build quantum cryptographic systems and quantum computers that certify that they work correctly. We discuss the perspectives for practical implementations.
This talk was filmed in December 2015 at the National University of Singapore.
13 дек 2015
