Does time exist?
Was our universe born from a Big Bang, or from a Big Bounce triggered by a former universe imploding?  Is this the only universe, or are there infinite ones, all expanding in parallel and out of sight of each other?
These are just some of the questions that will be tackled by world-renowned physicists Carlo Rovelli and Christophe Galfard when they come to the Intelligence Squared stage and are joined in conversation by BBC science star Helen Czerski. The venue is the Royal Geographical Society, in London.