Well, OK, not exactly. A beam of light could pass through air all day long (as long as you have a layer of air 26 billion kilometers long) and not deviate a whit. But if the density of that air ...

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.

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 ray of light is incident at normal incidence, (at right angles), to the surface between two optical materials, the ray travels in a straight line. When the ray is incident at any other angle, ...

When people look into a mirror, they see an image of themselves behind the glass. That image results from light rays encountering the shiny surface and bouncing back, or reflecting, providing a ...