The mind-bending concept of time dilation results from a seemingly harmless assumption—that the speed of light is the same for all observers.

Einstein’s theory of relativity shows us that time isn’t constant,it stretches or contracts based on speed and gravity. But ...

Inject these high-intensity intervals into your workouts to build race-day speed and resilience, along with a killer finishing kick.

Cory Pecinovsky, founder and CEO of the startup Polaris Electro-Optics, has bet his career on the proposition that the demand ...