Physics

You gotta read this last part of the article carefully. They are saying that a change at the end of a 10-kilometer fiber cable will cause something to happen at the beginning of the cable 50 seconds before the change is made. The researchers would adjust the position of the second detector to find the spot where the stream changes from a fuzzy diffraction pattern to a more defined, wavy interference pattern. Theoretically, because the streams contain entangled photons, the first detector should register the same changes 50 microseconds earlier.