It took 51 years to conduct what physicists consider the most robust experiment for validating the spookiness of quantum physics. Now researchers are getting good at it. Two papers posted online November 11 at arXiv.org confirm and strengthen recent results demonstrating that in the quantum world, events widely separated in spacetime don’t have to be independent. The findings could lead to improved techniques for securely exchanging information.
The two experiments, known as loophole-free Bell tests, were conducted at the National Institute of Standards and Technology in Boulder, Colo., and in the basement of Hofburg Palace in Vienna. Such complex experiments require clever problem-solving. To help satisfy the Bell test requirement of generating random numbers, the Boulder team used data from videos of Doctor Who and Saved by the Bell.
In both tests, photons bound in a state called entanglement were shown to have a connection that doesn’t follow the rules of classical physics. Each experiment clocked many more entangled particles than the first loophole-free Bell test, further reducing the already slim chance that the results are statistical flukes.