Fiber optic gyroscopes, which measure the rotation and orientation of airplanes and other moving objects, are inherently limited in their precision when using ordinary classical light. In a new study, physicists have experimentally demonstrated for the first time that using entangled photons overcomes this classical limit, called the shot-noise limit, and achieves a level of precision that would not be possible with classical light.
Source:
https://phys.org/news/2019-05-entangled-photon-gyroscope-classical-limit.html