When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The speed of light traveling through a vacuum is exactly 299,792,458 meters (983,571,056 ...

Discover how Einstein’s theory of special relativity reshaped physics by linking space, time, mass, and energy in a universe governed by the speed of light.

But that year, the British physicist Paul Dirac wrote down an equation that described an electron travelling at close to the speed of light and noticed that it contained something odd.