Dee ihe na-esote paragraf a - N'afọ ndị 1930 Bohr nyeere ndị gbara ọsọ ndụ site na Nazism aka. Mgbe ndị Germany weghaara Denmark
, o nwere nzukọ a ma ama na Heisenberg, onye ghọrọ onye isi nke German ngwá agha nuklia oru ngo. Na September 1943, Bohr nụrụ na ndị Germany na-aga ijide ya, ọ gbagara Sweden. Site n'ebe ahụ, e bugara ya Britain, ebe o sonyere na British Tube Alloys nuclear weapons project, ma bụrụ akụkụ nke ndị ọrụ Britain na Manhattan Project. Mgbe agha ahụ gasịrị, Bohr kpọrọ òkù maka imekọ ihe ọnụ mba nile n'ihe banyere ike nuklia. O tinyere aka na nguzobe nke CERN na Research Establishment Risø nke Danish Atomic Energy Commission wee bụrụ onye isi oche mbụ nke Nordic Institute for Theoretical Physics na 1957.