Professor Al-Khalili takes us from the discovery of the atom to the development of quantum mechanics

This episode tackles world-changing discoveries such as radioactivity, the Atom Bomb and the Big Bang, and tries to answer the biggest questions of all - why are we here and how were we made?

Al-Khalili discovers that there might be parallel universes in which different versions of us exist, and finds out that empty space isn’t empty at all, but seething with activity