On cold, sunny days, tiny ice crystals in the atmosphere can create breathtaking displays like halos, sundogs, and light pillars.

Light-matter interaction is one of the most fundamental ways to explore the physical world. While the reflection and refraction of light reveal the structural characteristics of matter, inelastic ...

Fresh snow can look like a blank sheet of paper, so bright it almost hurts to stare at in midday sun. Yet at the microscopic level, those flakes are not white at all, and the color we think we see is ...

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 ...

If you shine a light at a mirror, the beam is reflected inward to a central focal point, bouncing back toward you in a predictable manner—it’s a simple reflection of light, a spatial inversion. When a ...

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 ...

Light is well known to exhibit both wave-like and particle-like properties, as imaged here in this 2015 photograph. What's less well appreciated is that matter particles also exhibit those wave-like ...