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 ...

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 ...

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 ...

On Wednesday a total solar eclipse will pass over Iceland and other parts of Europe. Conducted on May 29, 1919, the Eddington experiment made the pages of Scientific American that same year. The ...

The theory of special relativity is rife with counterintuitive and surprising effects, the most famous of which are length contraction and time dilation. If an object travels at a relative speed, ...

As researchers detail in a study published today in the journal Nature, a star dubbed S301 exists so close to Sagittarius A*, ...

Albert Einstein’s mind reinvented space and time, foretelling a universe so bizarre and grand that it has challenged the limits of human imagination. An idea born in a Swiss patent office that evolved ...

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 ...

Monisha Ravisetti was a science writer at CNET. She covered climate change, space rockets, mathematical puzzles, dinosaur bones, black holes, supernovas, and sometimes, the drama of philosophical ...

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, ...

A rare 54-page manuscript featuring preliminary calculations for Albert Einstein’s general theory of relativity sold for about $13 million at auction in Paris Tuesday to an unknown buyer — almost four ...