Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still ...

There's nothing faster than the speed of light. So, what would happen if a human managed to move at this universal speed limit? When you purchase through links on our site, we may earn an affiliate ...

In the 1900s, Albert Einstein unified the concepts of space and time, giving us a useful new way to picture the universe. At the start of the 20th century, physicists had a problem: The speed of light ...