 They established in 1939 the possibility of nuclear chain reactions and nuclear energy production.While doing their research, the events of World War II forced them to eventually move to England, bringing with them the world's entire stock of heavy water, given on loan by Norway to France so that it would not fall into German hands.They continued their research at the Cavendish Laboratory in Cambridge for the MAUD Committee, part of the wartime Tube Alloys project.