A couple of articles, at the online sites for CNN and FoxNews, feature the work of Graeme Milton, a mathematics professor at the University of Utah. People have long imagined materials (like Harry Potter’s invisibility cloak) that would let light ‘pass through’ or ‘bend around’ any object that was cloaked, thus rendering the object invisible. In fact, that dream seems a long way off. However, Milton’s work shows that an alternative idea–cancelling out light waves coming towards an object, much like noise cancellation devices filter out noise–is entirely possible.
Milton’s results are purely mathematical at this point; as he says, “We just do the math and hope other people do the experiments.” But the research represents a new approach to cloaking, one that has wider applicability than to just light waves. “Results from the study demonstrate that it is conceivable to build cloaking devices that generate waves to create a quiet zone to protect oil rigs against incoming tsunami waves, or to create vibrations to neutralize incoming seismic waves from an earthquake.”