Vacuum structure and ether-drift experiments

In the data of the ether-drift experiments there might be sizable fluctuations superposed on the smooth sinusoidal modulations due to the Earth's rotation and orbital revolution. These fluctuations might reflect the stochastic nature of the underlying "quantum ether" and produce vanishing averages for all vectorial quantities extracted from a naive Fourier analysis of the data. By comparing the typical stability limits of the individual optical resonators with the amplitude of their relative frequency shift, the presently observed signal, rather than being spurious experimental noise, might also express fundamental properties of a physical vacuum similar to a superfluid in a turbulent state of motion. In this sense, the situation might be similar to the discovery of the CMBR that was first interpreted as mere instrumental noise.