Although the researchers did not have Bob and Alice generating random signals as truly secure cryptography requires, they did show that the signal timings and measurements could be performed over such great distances. (sciencemag.org)
The key to making them work was not searching for an ideal vibration frequency, but recognizing how complex systems in nature — like weather, for example — respond to random signals in the environment. (discovermagazine.com)
A newly developed computer program analyzes signals from the three antennas and filters out random signals from water vapor in the atmosphere, which are a million times stronger than the cosmic background, leaving only constant signals from cosmic microwaves. (discovermagazine.com)