So, you’re driving a car at half the speed of light. (Both hands on the wheel, please.) You turn on the headlights. How fast would you see this light traveling? What about a person standing by the ...

Dubbing these “closed timelike geodesics” (CTGs), Ralph and Sajeendran explain in the paper: “Such a CTG would be ideal for ...

Cosmic speed limits can be a major inconvenience but they've rarely stopped science fiction in its tracks. When it comes to space travel, Albert Einstein's theory of relativity is a major ...

When I was a teenager, I was—shockingly, I know—deeply nerdy. At a science-fiction convention, I bought a button that read, “186,282 miles/second: Not just a good idea, it’s the law.” It was poking ...