Cosmologist Laura Mersini-Houghton says our universe is one of many – and she argues that we have already seen signs of those other universes in the cosmic microwave background, the light left over from the big bang HOW did our universe begin? This is among the most profound questions of all, and you would be forgiven for thinking it is impossible to answer. But Laura Mersini-Houghton says she has cracked it. A cosmologist at the University of North Carolina at Chapel Hill, she was born and raised under communist dictatorship in Albania, where her father was considered ideologically opposed to…