Thursday, May 30, 2013

Experiment investigates how classical physics may emerge from quantum physics.

In order to better understand how the laws governing the quantum and classical regimes are related to one another, physicists have performed an experiment allowing them to observe a quantum-
to-classical transition in a simple closed quantum system. The results suggest that classical behavior may be an innate property of certain isolated quantum systems such as the one studied here, and can emerge from quantum physics under certain conditions.

The physicists, Bryce Gadway, et al., led by Professor Dominik Schneble at Stony Brook University in New York, have published their paper on the quantum-to-classical transition experiment in a recent issue of Physical Review Letters. Gadway is currently at the University of Colorado in Boulder.

"Our results suggest that classical physics may emerge in a very natural way in large quantum systems — in this case, 'large' meaning just two coupled subsystems — without the invocation of an external 'environment' responsible for decoherence," Gadway told Phys.org. "These results are certainly suggestive that classical behavior — specifically diffusive random-walk-like transport at the expected classical rate — is an innate property of this simple, quantum chaotic system."