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 ...

Physicists artificially slowed down time to reveal the bizarre Terrell-Penrose effect, a consequence of special relativity. This image from the experiment shows a sphere seemingly moving at 99.9 ...

Tiny “Ferris wheels” made from light and extremely cold particles could allow researchers to test a facet of Albert Einstein’s theory of relativity on unprecedentedly small scales. Theories of special ...

Another Silicon Valley investor is getting into the rocket business. Former Google chief executive Eric Schmidt has taken a controlling interest in the Long Beach, California-based Relativity Space.