It’s been 120 years since Henry Cavendish measured the gravitational constant with a pair of lead balls suspended by a wire. The fundamental nature of gravity still eludes our best minds - but those ...

Scientists have measured gravity at an extremely short distance, in what they hope will tell us more about extra dimensions. The rest of this article is behind a paywall. Please sign in or subscribe ...

PBS Space Time is available to stream on pbs.org and the free PBS App, available on iPhone, Apple TV, Android TV, Android smartphones, Amazon Fire TV, Amazon Fire Tablet, Roku, Samsung Smart TV, and ...

A recent study has made strides toward solving one of physics’ biggest puzzles: including all known particles and interactions into the theory of quantum gravity. The solution is to modify the quantum ...

In our universe there is a big problem with gravity. It is far weaker than the other fundamental forces and scientists cannot explain why. One proposal is that its energy is leaking into other, ...

Physicists are increasingly entertaining a radical possibility: our familiar universe of three dimensions of space and one of ...

Physicists wonder if our universe contains hidden extra dimensions. These dimensions could explain why gravity is so weak. They might be curled up so tightly we cannot see them. High-energy particles ...

Does our universe exist in more than just three dimensions? Probably not on large scales, according to new research published July 23 in the Journal of Cosmology and Astroparticle Physics. The study ...