'Spooky action at a distance' aboard the ISS

Albert Einstein famously described quantum entanglement as "spooky action at distance"; however, up until now experiments that examine this peculiar aspect of physics have been limited to relatively small distances on Earth.

In a new study published today, 9 April, in the Institute of Physics and German Physical Society's New Journal of Physics, researchers have proposed using the International Space Station (ISS) to test the limits of this "spooky action" and potentially help to develop the first global quantum communication network.

Their plans include a so-called Bell experiment which tests the theoretical contradiction between the predictions of quantum mechanics and classical physics, and a quantum key distribution experiment which will use the ISS as a relay point to send a secret encryption key across much larger distances than have already been achieved using optical fibres on Earth.

Their calculations show that "major experimental goals" could already be achieved with only a few overhead passes of the ISS, with each of the experiments lasting less than 70 seconds on each pass.