CAPE CANAVERAL SPACE FORCE STATION — Despite the number of struggles Relativity Space has faced trying to get the world’s first 3D-printed rocket off the ground, it finally succeeded Wednesday night, ...

Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still daring to test it. Some theories of quantum gravity suggest light might ...

A new theory suggests that gravity could possibly be the result of entropy. If true, this would mean that everything in the universe would fall apart if it all remained unchanged. This theory tries to ...

Time has an arrow: It only ever seems to move in one direction. The future is always unknown to us, while the past forever remains locked and inaccessible. And yet, the vast majority of the laws of ...