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, ...

The MICROSCOPE mission tested the weak equivalence principle with free-falling objects in a satellite. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it ...

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 ...

One of the most basic assumptions of fundamental physics is that the different properties of mass -- weight, inertia and gravitation -- always remain the same in relation to each other. Although all ...

We've all heard of relativity, but what is it? How does it relate to light and motion? So we've all heard of relativity, right? But... what is relativity? And how does it relate to light? And motion?

First of all, the prevailing quantum theory, quantum field theory, is fully relativistic from the onset. Relativity is “built into” the theory, so to speak. And it’s the only quantum theory that is ...