Scientists have demonstrated that negative refraction can be achieved using atomic arrays -- without the need for artificially manufactured metamaterials. Scientists have long sought to control light ...

When a wave or light ray moves from one medium to another its speed changes. The direction of the ray may also change. This property of waves is called refraction and commonly occurs with light rays.

This video looks at the refraction of light and demonstrates how refraction can make the handle of a Pyrex jug seemingly disappear.