Albert Einstein changed science forever with special and general relativity, redefining space, time, and gravity. Yet after his greatest triumphs, he became obsessed with something even bigger — a ...

What does it mean to be to space-time? The seemingly simple question gets to the essence of twentieth-century physics and has driven a hundred-year debate between philosophy and science. In Einstein’s ...

Researchers are using black hole “shadow” images to test whether Einstein’s relativity remains unshakable. With next-generation telescopes, they hope to spot telltale signs of alternative physics ...

Unfortunately, any work you do in the universe will have to be done the old-fashioned way. There may be an infinite amount of energy locked in the vacuum of space-time. So could we ever harness this ...

Einstein's theory of general relativity suggests that the "memory" of ancient events, such as black hole mergers, may be etched into the fabric of space-time by gravitational waves. New research shows ...

Science fiction is full of amazing space phenomena. Some of those phenomena have gone from theory to reality — like black holes and pulsars. But what about wormholes? These portals through space are ...