There is a fascinating story published in ScienceAlert about experiments in the measurement of quantum fluctuations in a vacuum. The story is here:
http://www.sciencealert.com/physicis...re-nothingness
The concept of squeezing a quantum vacuum and producing changes to quantum fluctuations within the vacuum is breakthrough stuff. Have a look at the graphic that shows the changes to quantum fluctuations when the vacuum is squeezed, and most amazing of all...... something else weird happens too, the fluctuations in some places appear to drop below the background noise level, which is lower than the ground state of empty space, something the scientists call an "
astonishing phenomenon".
What is happening in that area where it becomes lower than the noise floor?
Great stuff.