'Spooky' Quantum Entanglement May be Tested on International Space Station Over Longest Distance Yet

Quantum entanglement is a "spooky action at distance," according to Albert Einstein. It occurs when the entanglement connects two particles so that actions performed on one reflect on the other. Now, though, scientists have proposed testing this entanglement in an experiment on the International Space Station.

The proposal for this study, published in the New Journal of Physics, plans to include a Bell experiment, which is essentially a test of quantum entanglement. In particular, it would test the theoretical contradiction between the predictions of quantum mechanics and classical physics. In addition, the experiment would include a quantum key distribution experiment which would use the ISS as a relay point in order to send a secret encryption key 250 miles above the planet.

So far, quantum entanglement has only been established on relatively small scales in labs on Earth, according to Livescience.com. This new experiment, though, would take quantum entanglement to a whole new level. In practice, the scientists would fly a small device called a photon detection module to the ISS where it would be attached to an existing motorized camera lens. Scientists would then entangle a pair of light particles, called photons, on the ground. Then, one of these photons would be sent to the device on the ISS. The lab on the station would measure the properties of the photon in space while scientists would measure the one still on Earth. If they showed the ability to keep their entangled state, it would be the first ever proof that quantum entanglement could occur over such long distances. In addition, it would reveal the effect that gravity had on the phenomenon.

It's not only proof that the scientists are after, though. The ability to transmit information over such long distances could also have practical applications. Secret keys could potentially be passed across space and between cities without the threat of an eavesdropper intercepting it without being noticed.

That said, the experiment actually has to be conducted first. Until then, whether or not quantum entanglement will be have practical applications remains to be seen.