On one hand, the speed of light is just a number: 299,792,458 meters per second. And on the other, it’s one of the most important constants that appears in nature and defines the relationship of ...

The principle of relativity, as initially described by Galileo, posits that the laws of physics remain consistent regardless of an observer's relative motion. Einstein's special relativity ...

The glow from faster-than-light particles gives us a unique way to explore the universe. Nothing can travel faster than light — in a vacuum. But when light slows down, sometimes matter can blaze past ...

We throw around terms like “light year” and “faster than light travel” frequently. But to really understand the scale it helps to feel how fast the speed of light is. The flight simulation video below ...