Einstein's theory of gravity, general relativity, has passed all tests with predictions that are spot-on. One prediction that remains is "gravitational wave memory"—the prediction that a passing ...

Whenever light interacts with matter, light appears to slow down. This is not a new observation and standard wave mechanics can describe most of these daily phenomena. For example, when light is ...

Decades ago physicists realized that gravitational waves are no mere passing phenomenon. Instead those ripples in space should leave behind permanent marks: a fixed distortion in their wake. So far ...

Nearly two centuries after Michael Faraday first showed that magnetism can twist light, physicists have gone back to that classic experiment and found a hidden piece of the puzzle. By teasing out a ...

Can darkness really travel faster than light? A surprising new physics experiment suggests it can—at least in a very unusual way. Scientists observed dark regions within light waves moving faster than ...