A clear look at how physics defines gravity, from Newton’s force-based model to Einstein’s view of curved spacetime, and why the distinction matters in modern science.

The replacement of the continuous ring by discrete “nacelles” of exotic energy may be the most serious rethinking of ...

Most people picture a black hole forming the same way: a massive star runs out of fuel, collapses under its own gravity, and ...

General relativity describes gravity not as a force but as the curvature of spacetime produced by mass and energy. Matter tells spacetime how to curve, and this curved geometry guides the motion of ...

(Philipp Tur/iStock/Getty Images Plus) Right on the brink of black hole formation, spacetime can get downright peculiar. This is where familiar physics can become unnervingly strange, and ...