With the brilliant Professor Jim Al-Khalili as our host, we visit the LIGO lab in the USA where gravity waves were discovered, and uncover the latest theories about our cosmos that have come from studying the most intense sources of gravity imaginable – black holes.

In this episode, Jim uses Albert Einstein’s theories of special and general relativity to show how the rate at which you age is affected by gravity and the speed at which you move about in your daily life.