Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still ...

Einstein was right: artist's impression of a neutron-star merger. (Courtesy: NASA) Multimessenger observations of neutron stars have been used by astrophysicists in the US to put Einstein’s general ...

In general relativity the fabric of space-time is curved by large masses. This curvature is responsible for the force of gravity, and also deflects and delays any photons passing near a large mass, ...

Since its introduction by Albert Einstein in 1905 (ref. 1), special relativity has been the accepted theory of local space-time. It not only resolved severe open questions in electrodynamics but ...