LAST month, I answered a reader question about space-time expansion. They wanted to know what space-time is expanding into, given that we scientists tend to analogise with a balloon that is being ...

General relativity describes gravitation as the curvature of spacetime induced by the distribution of energy and momentum. In this framework, the stress–energy tensor encapsulates matter and field ...

General relativity stands as one of the bedrock theories in modern physics. Its strange view of relative time and space has been confirmed by countless experimental and observational tests, from ...

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 ...

The accelerating expansion of the universe could be explained by modifying general relativity so that gravity has mass – or so thinks a small group of physicists. Matthew Francis reports What lies ...

Albert Einstein’s mind reinvented space and time, foretelling a universe so bizarre and grand that it has challenged the limits of human imagination. An idea born in a Swiss patent office that evolved ...