The U.S. government is to patent a new quantum photonic imaging device that will detect anything underwater while providing unprecedented stealth for its submarines. Currently, submarines travelling through Arctic waters have to use gyroscopes and accelerometers to measure the motion and rotation of the vehicle in order to estimate the current position, orientation and velocity of another submarine – as GPS signals are unable to reach underwater. International Business Times reports: They could use an active sonar array detection system in order to spot ice canopies underwater to prevent accidental collisions, but the drawback of using this is that it reveals the position of the submarine to any enemies underwater. However, in areas of high latitude such as the North Pole, gyroscopes and compasses become unreliable due to proximity to the geomagnetic North Pole and the Earth’s rotation axis, so the Navy has no choice but to use the active sonar array. To solve this problem, a new patent application filed by the US government describes a quantum photonic imaging device that uses quantum entanglement to silently detect and identify targets. The device generates a pair of entangled photons, and one of the photons, known as the “signal photon”, is transmitted [...]