China has launched a satellite that will beam entangled photons to base stations on Earth:
China has successfully launched the world's first quantum-enabled satellite, state media said. It was carried on a rocket which blasted off from the Jiuquan Satellite Launch Centre in China's north west early on Tuesday. The satellite is named after the ancient Chinese scientist and philosopher Micius. The project tests a technology that could one day offer digital communication that is "hack-proof". But even if it succeeds, it is a long way off that goal, and there is some mind-bending physics to get past first.
The satellite will create pairs of so-called entangled photons - tiny sub-atomic particles of light whose properties are dependent on each other - beaming one half of each pair down to base stations in China and Austria. This special kind of laser has several curious properties, one of which is known as "the observer effect" - its quantum state cannot be observed without changing it. So, if the satellite were to encode an encryption key in that quantum state, any interception would be obvious. It would also change the key, making it useless.
(Score: 2) by wonkey_monkey on Wednesday August 17 2016, @03:36PM
Doesn't that mean that the wave will cover a huge area on earth?
Nope. It'll be tightly focused. Has to be.
If it wasn't, for some reason, and you were able to detect a photon at some remote site, that wouldn't have been one of the ones that would end up being used in the encryption key anyway, as it woudn't have been received at the receiving station.
systemd is Roko's Basilisk