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 ...

Refraction close refractionProcess by which a wave changes speed and sometimes direction upon entering a denser or less dense medium, eg a light ray changes direction when refracted by a lens. of ...

Can we turn back time? Ask a savvy physicist, and the answer will be “it depends.” Schemes for retrograde time travel abound but usually involve irreconcilable paradoxes and rely on outlandish ...

Exploiting a novel technique called phase discontinuity, researchers have induced light rays to behave in a way that defies the centuries-old laws of reflection and refraction. The discovery has led ...

As showing how far under favourable conditions the reflection of light from a cloudy sky is visible, I may perhaps be allowed to mention that last night at nine o'clock the reflection of the London ...

Have you ever sat on the bottom of a swimming pool and pondered your watery ceiling? Most of the surface is a sheet of light blue, and you can't see through it, even though the water is clear. But ...