clipped from: www.redorbit.com 
Naval warships might look like all-powerful vessels but they are also highly vulnerable to being spotted by the enemy. That fear of being detected has led the military to develop new stealth technologies that allow ships to be virtually invisible to the human eye, to dodge roaming radars, put heat-seeking missiles off the scent, disguise their own sound vibrations and even reduce the way they distort the Earth’s magnetic field, as senior lecture in remote sensing and sensors technology at Britannia Royal Navy College, Chris Lavers, explains in March’s Physics World.
About the research, Chris Lavers writes, “If optical and radar metamaterials could be developed, they might provide a way to make a ship invisible to both human observers and radar systems, although the challenges of building a cloak big enough to hide an entire ship are huge.”