Physicists go totally random

Calculations suggest way to boost the independence of information flow

Casino bosses, take note: Physicists have described a way to guarantee complete randomness in a flow of information, such as the numbers generated by a roulette wheel.

The work could allow a person to transform a stream of not-quite-random information into a totally random one. “Even if you don’t have perfect randomness, you can make perfect randomness,” says Roger Colbeck, a theoretical physicist at ETH Zurich in Switzerland.