Scientists simulate quantum computer

D. Cory of the Massachusetts Institute of Technology, Raymond Laflamme of Los Alamos National Laboratory and colleagues report that have come up with a general scheme for quantum simulation that would work on any quantum computer. In a paper in the June 28 issue of Physical Review Letters, the researchers say they demonstrated the scheme on a liquid-state nuclear magnetic resonance quantum computer developed at MIT. The possible applications of quantum computing techniques have been studied since the 1980s. But the field took off in earnest only in 1994, when AT&T mathematician Peter Shor discovered that quantum computing could efficiently find the prime factors of large numbers. Such prime factorization could provide a method for cracking some of the most widely used methods for encrypting sensitive data. Around the same time, Seth Lloyd, associate professor of mechanical engineering at MIT, proposed that a quantum computer could be built from an array of coupled two-state quantum systems, each of which can store one quantum bit, or qubit. Cory_s research group, and Neil Gershenfeld and colleagues in MIT_s Artificial Intelligence Laboratory, with Isaac Chuang at IBM, independently helped develop the quantum computer. At the moment, quantum computers don_t possess the calculating power of a pocket calculator. But quantum computing has the potential to surpass conventional computing techniques in power and efficiency. Because quantum mechanics allows a quantum computer_s components to represent many states simultaneously, it should be able to perform many computations simultaneously. A quantum computer may be able to solve quickly problems involving weather prediction and fluid flow - problems so big they couldn_t be stored in a conventional computer_s memory.