Scientists Who Invented the Atomic Bomb under the Manhattan Project: Robert Oppenheimer, David Bohm, Leo Szilard, Eugene Wigner, Otto Frisch, Rudolf Peierls, Felix Bloch, Niels Bohr, Emilio Segre, James Franck, Enrico Fermi, Klaus Fuchs and Edward Teller.
Probably one of the best quotes of this time period:
"My God, what have we done?" - Robert Lewis, the co-pilot of the Enola Gay, the B-29 that dropped the first atomic bomb.