String theory is a purported theory of everything that physicists hope will one day explain … everything. All the forces, all the particles, all the constants, all the things under a single ...

Could the universe have hidden dimensions we’ve yet to detect? The idea of extra dimensions has intrigued physicists for over a century, and while there’s no solid evidence to prove their existence, ...

For more than a century, physicists have suspected that the familiar three dimensions of space and one of time might be only a sliver of reality. Extra dimensions, if they exist, would not just be a ...

We tend not to dwell on the fact that we exist in three dimensions. Forwards-back, left-right, up-down; these are the axes on which we navigate the world. When we try to imagine something else, it ...

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 ...

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 ...

In 1919, physicist Theodor Kaluza hypothesized that extra dimensions might solve some outstanding problems in physics. And while we haven't found any evidence yet for anything outside our normal ...