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 ...

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 ...

Scientists have taken one more step down the very long road to time travel. A new paper combines the Alcubierre “warp” drive with the idea of “controlled closed timelike curves.” Though far out, ...