The discovery of black holes is a dramatic story of bitter scientific rivalry, born of clashing cultures and world-views Quentin Cooper talks to Arthur Miller , professor of history and philosophy of science, and physicist Dr Jim Al -Khalili about the history and science behind these regions of space-time into which matter has collapsed, and out of which light may not escape. Has the theory become a reality? Do black holes really exist and where do we start looking for them, given that we can't see them? Producer Michelle Martin