Researchers have shown that a liquid, ultra-cold helium-3, demonstrates quantum interference, just as the classic “two-slits” experiment shows that a beam of light is a quantum wave.

This quantum interference is identical to the interference between light waves, electrons, atomic beams and electrical currents in solid superconductors. It had never before been observed in a liquid.

The findings by UC Berkeley researchers was published in Nature (vol 412, p55).

One potential application of this quantum interference is in an ultrasensitive superfluid gyroscope, able to measure extremely slight increases or decreases in the rotation of objects, including Earth.