Ya koma Cibiyar Nazarin Ka'idar Kimiyya (daga baya Cibiyar Niels Bohr) a Copenhagen a kan Sheldon Traveling Fellowship daga Harvard, kuma ya kasance a Denmark. A shekara ta 1953 an nada shi memba na ma'aikata a Cibiyar Nazarin Ka'idar CERN, wanda ke zaune a Copenhagen, wani matsayi da ya yi har sai ya zama farfesa a sabon Cibiyar Nazarin Ka'idar Nordic (Nordita) a shekara ta 1957. Ya kasance farfesa mai ziyara a Jami'ar California, Berkeley a Spring 1959. A shekara ta 1971 ya zama dan kasar Danish. Tambaya: Yaushe ya zama dan kasar Denmark?
Shekara ta 1971