Cambridge and Göttingen 1929
In Cambridge next term (January 1929), I remember Patrick Blackett (later Lord Blackett and President of the Royal Society) saying—'you are a changed character, Mott, since Copenhagen. You are in the lab. all day!' And it was then that the work occurred that really established me as a physicist. It began in Copenhagen. A paper by J. R. Oppenheimer (later famous as a leader in the atomic bomb project)showed that, in collision problems, when electrons hit atoms, quite large effects dependent on the spin direction could occur.