Sorry, Einstein. Quantum Study Suggests ‘Spooky Action’ Is Real

by John Markoff, The New York Times

Delft University of Technology scientists report validating quantum theory’s fundamental claim of the phenomenon of spooky action, in which objects separated by great distance can instantaneously affect each other.

Their experiment, described as a “loophole-free Bell test,” eliminates all possible hidden variables by entangling a pair of diamond-entrapped electrons 1.3 kilometers apart and then sharing information between them, using detectors on opposite sides of the Delft campus to ensure no conventional information exchange is possible. Pulses of microwave and laser energy are then applied to entangle the electrons and measure their spin.

Massachusetts Institute of Technology physicist David Kaiser says only two out of three major quantum loopholes have been closed by the Delft experiment. He notes the electronic system the researchers used to add randomness to their measurement may actually be subtly predetermined, meaning the outcome also might still be predetermined.

“What I do find interesting is that the experimenters are learning how to manipulate quantum systems, and do experiments that are far beyond what was possible when I was starting in physics,” said Leonard Susskind, a theoretical physicist at Stanford. “Things which were at best ‘thought experiments’ become possible, then routine. That is incredibly impressive.”

Indeed, the experiment is not merely a vindication for the exotic theory of quantum mechanics, it is a step toward a practical application known as a “quantum Internet.” Currently, the security of the Internet and the electronic commerce infrastructure is fraying in the face of powerful computers that pose a challenge to encryption technologies based on the ability to factor large numbers and other related strategies.

Some researchers  envision a quantum communications network formed from a chain of entangled particles girdling the entire globe. Such a network would make it possible to securely share encryption keys, and know of eavesdropping attempts with absolute certainty.

The U.S. National Science Foundation is funding work by Kaiser and others to close the final loophole via an experiment to measure light from distant objects on different sides of the galaxy. Such work is seen as a step toward a “quantum Internet” composed of entangled particles that offers absolute security.  Read the article