For more than a century, gravity has been the stubborn outlier in physics, resisting every attempt to merge Einstein’s smooth space-time with the jittery world of quantum mechanics. A new wave of ...

Einstein’s claim that the speed of light is constant has survived more than a century of scrutiny—but scientists are still ...

The theorized unseen structure of spacetime could also explain of the outstanding questions about the accelerating expansion of the universe.

Bootstrapping strings Evidence that string theory could be the sole viable “theory of everything” has emerged in a new theoretical study of particle scattering. (Courtesy: iStock/Anadmist) Striking ...

Physicists speak of the world as being made of particles and force fields, but it is not at all clear what particles and force fields actually are in the quantum realm. The world may instead consist ...

A new study enhances hydrogen molecule predictions, achieving unprecedented precision in testing fundamental physics and ...

The idea of the multiverse — or the theoretical possibility of infinite parallel universes–straddles a strange world between science fiction and a plausible hypothesis. Though scientists have no ...

Can a theory that isn’t completely testable still be useful to physics? What determines if an idea is legitimately scientific or not? This question has been debated by philosophers and historians of ...

Pick up any science fiction book from the 1960s, and you’ll find parallel dimensions explained through magic portals or mysterious machines that work “just because.” Today’s readers want stories that ...