Has the future already already been written? Is time just an illusion? Take a step outside of spacetime with cosmologist Marina Cortês to discover the block universe.

Marina Cortês is one of a growing number of physicists who believe time is fundamental. We ask her about the alternatives theories to the block universe, where time comes first.

The possibility that there might be many parallel worlds has just become a little more likely.

A model of the interaction between predators and prey explains why sometimes frogs appear to eat snakes.

Mathematical models predict how fast a rumour will spread and how many people it's likely to reach.

What would happen if the Sun suddenly exploded? Einstein wondered the same thing, and completely changed our understanding of the Universe.

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.