Stuff happens

Why are physicists unsure about what it means to say that something has happened? Anthony Aguirre and Sean Carroll explain.

A model of backward causation in which the future affects the past could help unite quantum mechanics and general relativity – and satisfy a challenge thrown down almost a century ago by Arthur Eddington.

Mapping the ancestral history of spacetime in an effort to unite quantum mechanics and general relativity.

A new model argues the forces between particles in the early universe loosed time’s arrow, creating temporal order from chaos.

How can it be that our wonderfully complex world is governed by a few comparatively simple laws of nature? Find out with this collection of articles and videos.

How simples rules can result in very complex outcomes.

We all know what symmetry is. But why does it play such a central role in modern physics?

A closer look at the power of symmetry in physics.

Science is the study of events: things that happen in the world around us. But what exactly is an event? The answer is harder than you might think.

Can simple equations really describe the complex world we live in?