Physics: A quantum less quirky

Seth Lloyd

Eric L. Michelsen

From encrypting e-mail messages to simulating the collapse of stars, many scientific procedures require random numbers. But generating truly random numbers with a computer is impossible. Computers can only follow algorithms, and no matter how convoluted, an algorithm tells you how to get the next number from all the preceding ones. Mother Nature, however, is less predictable, and three Web sites rely on quirky physical processes to provide the truly random bits you crave.

Peter Woit

M. Lamonica

Using the quirky laws of quantum physics to encrypt data, in theory, assures perfect security. But today's quantum cryptography can secure point-to-point connections only about 100 kilometers apart, greatly limiting its appeal.

Felix Cheung