When an object moves extremely fast—close to the speed of light—certain basic assumptions that we take for granted no longer apply. This is the central consequence of Albert Einstein's special theory ...

The theory of special relativity is rife with counterintuitive and surprising effects, the most famous of which are length contraction and time dilation. If an object travels at a relative speed, ...

A snapshot of relativistic motion: Experimental data on the Terrell rotation of a deliberately Lorentz contracted sphere at 0.999 c, moving from right to left. (Courtesy: Dominik Hornof et al., "A ...

We've all heard of relativity, but what is it? How does it relate to light and motion? So we've all heard of relativity, right? But... what is relativity? And how does it relate to light? And motion?

The contraction of a measured length of an object or a distance in a frame of reference moving at nearly the speed of light, predicted by the theory of special relativity.