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. Without this ...

Albert Einstein might be astonished to learn that NASA physicists have applied his relativity theory to a concept he introduced but later disliked namely that two particles that interact could ...

For those who watch gravitational waves roll in from the universe, GW250114 is a big one. It's the clearest gravitational wave signal from a binary black hole merger to date, and it gives researchers ...

Physicists have measured Albert Einstein's theory of general relativity, or more specifically, the effect called time dilation, at the smallest scale ever, showing that two tiny atomic clocks, ...

The weak-equivalence principle is integral to general relativity, so these test results offer yet more support for a core theory of our universe. In 1916, Albert Einstein dared to declare that Isaac ...

Learn how researchers used Einstein’s theory of general relativity to create the most accurate simulations to date. Think of a black hole, and you might imagine a literal dark hole, but contrary to ...

110 years ago today, Albert Einstein published his General Theory of Relativity, which redefined the relationship between matter and gravity. Suddenly, our mysterious universe made a little more sense ...

We all have some past events that we'd like to undo. These can be minor moments, such as a failed exam or an argument with friends, or world-changing incidents, such as the 2019 outbreak that led to ...