Illusion Cloak Makes One Object Look like Another. Fiddle with an invisibility cloak, and it can make any object look like another, say researchers.
Just when you thought invisibility cloaks couldn't get any weirder, researchers come up with this: a way to make one object look like any other. Invisibility cloaks work by steering light around a region of space, making any object inside that region invisible. In effect, an invisibility cloak creates the illusion of free space. This is possible because of a new generation of artificial materials called metamaterials that can, in principle at least, steer light in any way imaginable. Indeed, various teams have built real invisibility cloaks that hide objects from view in both the microwave and optical bands. Now Che Chan and pals from the Hong Kong University of Science and Technology say that metamaterials could be used for an even more exotic effect: for cloaks that create the illusion that a different object is present. The illusion is a two-step process, and to see how it works, imagine making a mouse look like an elephant. The first step involves an idea that these guys came up with about six months ago in which they described a way of cloaking objects at a distance. The trick is to create a material in which the permittivity and permeability are complementary to the values in a nearby region of space containing the mouse we want to hide. "Complementary" means that the material cancels out the effect that the mouse has on a plane lightwave passing through. So a plane wave would be bent by the mouse but then bent back into a plane as it passes through the complementary material, making the mouse disappear. more... http://www.technologyreview.com/blog/arxiv/23519/ _______________________________________________ NetBehaviour mailing list NetBehaviour@netbehaviour.org http://www.netbehaviour.org/mailman/listinfo/netbehaviour
