Theoretical physicists have spent decades wrestling with a disorienting possibility: that the flow of time is not woven into the basic laws of physics but instead emerges from gravity’s effect on heat ...

For those who watch gravitational waves roll in from the universe, GW250114 is a big one. It's the clearest gravitational wave signal from a binary black hole merger to date, and it gives researchers ...

Planets orbiting dead stars known as white dwarfs might be able to remain habitable thanks to general relativity subtly altering their motion. When stars like our sun run out of fuel, they expand and ...

New impressions A visualization of a curved space–time “sea” from the general-relativity simulations carried out by the authors.(Courtesy: James Mertens) From the Genesis story in the Old Testament to ...