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 ...

Light consists of electromagnetic waves that oscillate in time and propagate in space. Scalar waves are described by their intensity and phase distributions. These are the spatial (orbital) degrees of ...

Introduction Can you imagine a bouncy ball that could bounce back and forth between two walls, infinitely—that is, forever? Wouldn't that be amazing? What if, instead of a ball, light was bouncing ...

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 ...

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 ...

With walls and ceilings a long way away, often the most practical way to control the placement of a light source and the positioning of light, is to drop it into the exact position where it’s required ...