The Physics of Invisibility

Book excerpt: The ability is see is fundamental to our very existence. How true our perceptions really are depends upon many factors, and not least is our understanding of what light is and how it interacts with matter. It was said that the camera, the icon of light recording instruments, never lies, and in the day of the glass plate and celluloid roll-film this might well have been true. But in this modern era, with electronic cameras and computer software, it is often safe to assume that the camera always lies. The advertising images that bombard our every waking moment are manipulated in shape, profile, color, and form. In this new era, light can be manipulated with metamaterials to make one object look like another or even cause that objects to vanish, literally before our eyes; not only can the image we see be manipulated, but so can the light itself.