Particles of light – photons – are massless, so they normally pass right through each other. This generally means they can’t ...

“Our demonstration of a very counter-intuitive optical effect invites us to reconsider our notion of shadow.” Researchers showed that a laser beam can sometimes act like a solid object and cast a ...

Can light cast a shadow? It sounds like a tricky riddle, but researchers have shown that, under special conditions, a laser ...

The result is a darker area that appears as a shadow of the green laser beam. Researchers showed that a laser beam can sometimes act like a solid object and cast a shadow that is visible to the naked ...

A shadow is a dark shape made when light is stopped or blocked by an object or a person. Some objects are opaque such as stone, metal and wood. This means light doesn't travel through them.