Space-time

New findings are fueling an old suspicion that fundamental particles and forces spring from strange eight-part numbers called “octonions.”

Mathematicians have disproved the strong cosmic censorship conjecture. Their work answers one of the most important questions in the study of general relativity and changes the way we think about space-time.

A recently proposed experiment would confirm that gravity is a quantum force.

Edward Witten reflects on the meaning of dualities in physics and math, emergent space-time, and the pursuit of a complete description of nature.

Physicists theorize that a new “traversable” kind of wormhole could resolve a baffling paradox and rescue information that falls into black holes.

The effort to unify quantum mechanics and general relativity means reconciling totally different notions of time.

String theory has so far failed to live up to its promise as a way to unite gravity and quantum mechanics. At the same time, it has blossomed into one of the most useful sets of tools in science.

Just months after their discovery, gravitational waves coming from the mergers of black holes are shaking up astrophysics.

Richard Feynman's famous diagrams weren’t just a way to do calculations. They represented a deep shift in thinking about how the universe is put together.