Edunomia – Un diari sobre aspectes de la Universitat – per Miquel Duran

Números aleatoris quàntics


He vist a slashdot un servei de números aleatoris obtinguts a partir d’un fenomen quàntic:

What the world needs is more truly random sources of numbers. Researchers from Australian National University have found a brilliant way to make one: ‘We do this by splitting a beam of light into two beams and then measuring the power in each beam. Because light is quantised, the light intensity in each beam fluctuates about the mean. Those fluctuations, due ultimately to the quantum vacuum, can be converted into a source of random numbers. Every number is randomly generated in real time and cannot be predicted beforehand.’ So if you need some really random numbers, just use their generator service.”

Els comentaris a l’entrada de Slashdot són divertits, i en particular aquesta cita: “La generació de números aleatoris és massa important per deixar-la a la sort

The generation of random numbers is too important to be left to chance.
– Robert R. Coveyou, Oak Ridge National Laboratory

Seriosament, ja hi ha generadors de números quàntics comercials, que es fan servir sobretot per a criptografia quàntica. No sé si aquest servei és real o fictici, però té gràcia. Segons el web de l’Australian National University que proporciona aquest novedós servei,

This website offers true random numbers to anyone on the internet. The random numbers are generated in real-time in our lab by measuring the quantum fluctuations of the vacuum. The vacuum is described very differently in the quantum mechanical context than in the classical context. Traditionally, a vacuum is considered as a space that is empty of matter or photons. Quantum mechanically, however, that same space resembles a sea of virtual particles appearing and disappearing all the time. This results in the fact that the vacuum does not possess a zero-point energy, and consequently the electo-magnetic field describing this vacuum possesses random fluctuations in phase and amplitude at all frequencies. By carefully measuring these fluctuations, we are able to generate ultra-high bandwidth random numbers.

This website allows everybody to download our quantum random numbers, assess in real time the quality of the numbers generated and learn more about the physics behind it.

La visualització dels nombres aleatoris quàntics és força bonica. Per exemple, l’anomenada “Matrix”, que és dinàmica.


This entry was posted on 14/04/2012 by in Ciència, Criptografia.