So what could be called a marriage was defined by religious organisations, which might answer the question in different ways, while the state didn't attempt to intervene in the definition of marriage.

BBC: Trench warfare

The answer to that puzzle will require considering different ways in which these particles and others decay into yet more particles from the zoo that may finally show enough CP violation to close the antimatter question.

BBC: Antimatter results emerge at LHC - but puzzle abides

In their own different ways, Sargent and Sims produced crucial tools for economists to answer these questions, which are still being used today.

BBC: The Nobel prize, and the ONS