Some of the hardest questions in cosmology begin where the usual math gives up. Push Einstein’s theory far enough back toward ...

Einstein’s general theory of relativity has been tested for the first time over distances nearly as large as the universe itself – and has, in the process, trumped most other alternative theories of ...

Time feels familiar. It marks every moment of daily life, from the ticking of a wall clock to the changing numbers on a ...

An analysis of more than 70,000 galaxies by University of California, Berkeley, University of Zurich and Princeton University physicists demonstrates that the universe – at least up to a distance of 3 ...

Space and time looked settled, at least in broad outline. Einstein's special relativity gave physics a durable framework for describing motion, and for more than a century one boundary seemed firm: ...