Bounding the speed of `spooky action at a distance'

In the well-known EPR paper, Einstein et al. called the nonlocal correlation in quantum entanglement as spooky action at a distance'. If the spooky action does exist, what is its speed? All previous experiments along this direction have locality loopholes and thus can be explained without having to invoke any spooky action’ at all. Here, we strictly closed the locality loopholes by observing a 12-hour continuous violation of Bell inequality and concluded that the lower bound speed of `spooky action’ was four orders of magnitude of the speed of light if the Earth’s speed in any inertial reference frame was less than 10^(-3) times of the speed of light.