Are there more possible games of chess than atoms in the universe?

We investigate how the vast possibilities in a game of chess compare to the vastness of the observable universe.Dr James Grime helps us understand the Shannon number – a famous figure on the chess side of the equation - and astronomer Professor Catherine Heymans takes on the entire observable universe. Presenter: Tim Harford Producers: Debbie Richford and Nathan Gower Production Co-ordinator: Brenda Brown Series Producer: Tom Colls Sound Mix: Andy Fell Editor: Richard Vadon