For over a century, quantum mechanics and Einstein’s general relativity have stood as the cornerstones of modern physics, yet their unification remains one of science’s greatest challenges. Now, ...

A Precision Test of General Relativity. While Einstein’s famous theory of general relativity accurately describes the motion of celestial bodies in our solar system, less is kno ...

The grandfather paradox is just one of the thorny logical problems that arise with the concept of time travel. But one ...

The accelerating expansion of the Universe, first observed in 1998, remains one of the most profound mysteries in modern ...

Albert Einstein's general theory of relativity is one of the towering achievements of 20th-century physics. In our introduction to general relativity, we explain how this theory developed ...

General relativity, formulated by Albert Einstein, describes the gravitational force as a curvature of spacetime caused by mass and energy. The mathematical aspects of general relativity involve ...

General relativity describes gravitation in a geometrical framework generalizing special relativity and classical mechanics. This term includes theoretical studies of gravity, experimental studies ...

On 25 November 1915, Albert Einstein presented his general theory of relativity at the Prussian Academy of Sciences. This theory is still considered to be the most important idea in modern physics.

This NASA/ESA Hubble Space Telescope image reveals a tiny patch of sky in the constellation Hydra. The stars and galaxies depicted here span a mind-bending range of distances. The objects in this ...

NOVA: Do you think string theory will ever be accepted as widely as, say, the theory of general relativity? What would it take for that to happen? Greene: Well, the real reason why general ...

To celebrate the 100th anniversary of its publication, Brian Cox and the world's leading cosmologists take Robin Ince on a guided tour of Einstein's Theory of General Relativity ...