JF Ptak Science Books Quick Post
I wanted to reproduce Wolfgang Pauli's letter of 4 December 1930--in it he thinks very widely of missing stuff, of some of the basic bits of the universe, in a rather open and guarded way, about the ghost of the neutron. He didn't feel very comfortable with his ideas yet, at least for professional consumption--that would have to wait another three years when it was discussed at the 7th Solvay Conference (1933) and another three when it first came into print (1936). The name "neutron" would also be changed to the familiar "neutrino" ("little one") by Enrico Fermi in 1933 to differentiate it from the much larger nuclear particle discovered the year earlier by James Chadwick--Chadwick's paper was published in Nature, which would reject Fermi's paper in 1934 as too radical a leap.
[Source: Exhibition of the ETH-Bibliothek to the occasion of the 100th birthday ofWolfgang Pauli http://www.library.ethz.ch/exhibit/pauli/neutrino_e.html]
Translation via the History of the Neutrinos page (here):
"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