Pauli's letter of the 4th of December 1930
Dear Radioactive Ladies and Gentlemen,
As the bearer of these lines, to whom I graciously ask you to listen,
will explain to you in more detail, how because of the "wrong" statistics of the
N and Li6 nuclei and the continuous beta spectrum, I have hit upon
a deseperate remedy to save the "exchange theorem" of statistics and the law of
conservation of energy. Namely, the possibility that there could exist in the
nuclei electrically neutral particles, that I wish to call neutrons, which have
spin 1/2 and obey the exclusion principle and which further differ from light quanta
in that they do not travel with the velocity of light. The mass of the neutrons
should be of the same order of magnitude as the electron mass and in any event not larger
than 0.01 proton masses> The continuous beta spectrum would then become understandable by
the assumption that in beta decay a neutron is emitted in addition to the electron
such that the sum of the energies of the neutron and the electron is constant...
I agree that my remedy could seem incredible because one should have seen those
neutrons very earlier if they really exist. But only the one who dare can win and the
difficult situation, due to the continuous structure of the beta spectrum, is lighted
by a remark of my honoured predecessor, Mr Debye, who told me recently in Bruxelles:
"Oh, It's well better not to think to this at all, like new taxes". From now on,
every solution to the issue must be discussed. Thus, dear radioactive people, look and judge.
Unfortunately, I cannot appear in Tubingen personally since I am indispensable here in
Zurich because of a ball on the night of 6/7 December. With my best regards to you, and also
to Mr Back.
Your humble servant
.
W. Pauli
Didier Verkindt