Special relativity states – among other things – that the speed of light is the same no matter how fast an observer is travelling. The so-called Kennedy-Thorndike experiment tests this prediction by ...

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?

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 ...

The breakthrough could suggest a way to study 'quantum gravity,' the missing link between quantum physics and Einstein's general relativity in the lab. When you purchase through links on our site, we ...

Physicists are close to performing the most accurate tests of Einstein’s ideas about gravity ever undertaken. Their first-of-its-kind experiment involves using two kinds of extremely cold atoms aboard ...

Observing time distortions could show whether Einstein's theory of general relativity accounts for the mysteries of dark matter and dark energy. When you purchase through links on our site, we may ...

Yesterday, I wrote about the core concepts needed to understand quantum physics, which is one of the two pillars of modern physics. The other, of course, is the theory of relativity, the full and ...