# Samuel Goudsmit

Samuel Abraham Goudsmit (July 11, 1902 – December 4, 1978) was a Dutch-American physicist famous for jointly proposing the concept of electron spin with George Eugene Uhlenbeck in 1925.

## Sourced

* We must expect that these German scientists, once they get here, will continually try to defend the actions of Germany before and during the war. Their background and education wiil have supplied them with the necessary arguments. The rocket specialists have at times tried to convince us that they worked on rockets only for the purpose of scientific research. The German atomic scientists, who failed in their attempt to make a bomb, planned to deny that they wanted to make one.
** (1947). "German Scientists in Army Employment". Bulletin of the Atomic Scientists 3 (2): 64–67. ISSN 0096-3402. DOI:10.1080/00963402.1947.11455849.
* I did all the problems a little different from the rest of the class.
** in an interview by Thomas Samuel Kuhn on December 5, 1963, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA
* ... I don't like the history of physics, I have always been against the way in which the historians wrote about it in earlier days. Nowadays it is better, someone like Martin Klein, that is real, he brings something new. But the earlier historians always described physics as if it had been done by three and four people and they forgot that these famous people could only do their work because of the many others who also made contributions. ...
** (as translated by J. H. van der Waals from Goudsmit's lecture given in April 1971): "Chapter A.1. The discovery of the electron spin". Foundations Of Modern EPR. 1998. pp. 1–12. (quote from p. 3)
* In my study hangs a fine old horse shoe, which I found in an abandoned Western ghost town. I don't believe in superstitions, but it is supposed to work even for a nonbeliever$^2$. It hasn't so far.
    $^2$ For historians: This fact was conveyed to me in 1941 by I. Bernard Cohen, the historian of science at Harvard University. I passed it on to Niels Bohr in 1954 when he visited Brookhaven. It is now known as "Bohr's story". W. Heisenberg, in his book Der Teil und das Gauze, incorrectly has Bohr telling it already in 1927.
** Bias (Physical Review Letters 25 (1970) 419-20)

### Alsos (1996 edition)

* In short, we knew very little about the German uranium project, and what little we knew we almost invariably interpreted in their favor. In the long run, this was probably all to the good, since it accelerated our own work enormously. But in those days, before the invasion of Europe, we would have given a great deal to know more.
** Samuel A. Goudsmit (1996). Alsos. Springer Science & Business Media. p. 10. ISBN 978-1-56396-415-2. (with a new introduction by David Cassidy; originally published in 1947 by Henry Schuman, Inc., New York)
* If only we could get hold of a German atomic physicist, we felt, we could soon find out what the rest of them were up to. To us physicists the problem seemed very simple. Even those of us who were not working on the atom bomb project knew pretty well what was going on over here. No amount of military security could have prevented us from knowing, difficult as it was for the military to understand this. Active scientists engaged in the same general field of research inevitably form a kind of clan; they work closely together and know all about each other's specialities and whereabouts. You can't take a group of key scientists from their accustomed haunts and have them disappear in some remote place in New Mexico, together with their families, without their colleagues who are left behind wondering about it and deriving the right conclusions. The same thing, we knew, would be true of the Germans.
** pp. 11–12
* Secrecy, it was impressed upon us at the outset, was imperative, despite the fact that our code name, ALSOS, seemed a give-away, being the Greek translation for Groves. Since General Groves was in complete charge of all Army activities relating to the atom bomb project, the inference did not take too much imagination. To make it even more obvious, the Mission's vehicles had license plates bearing the Greek letter Alpha.
** p. 26

## About Goudsmit

* Goudsmit stumbled to fame in 1925. For more than a decade, Niels Bohr and others had been trying to develop a quantum theory of the atom, mostly by studying atomic spectra. These consist of the energies (specific to each element) of the quanta of light, or photons, that an atom’s electrons can absorb or emit. Physicists had been struggling to make sense of anomalies that appeared in spectra when atoms were immersed in a magnetic field: some spectral levels mysteriously split into two or more. Goudsmit and his friend George Uhlenbeck, both graduate students at Leiden University in the Netherlands, had an idea. They proposed that the splitting could be explained if the electron had an intrinsic ‘spin’ that could assume one of two directions: clockwise or anticlockwise. Other physicists had discarded this idea, seeing it as marred by conceptual difficulties. ... Soon, researchers including Paul Dirac explained away the conceptual difficulties. Quantum spin was born.
** Davide Castelvecchi, (2018). "The forgotten quantum pioneer who turned wartime spy". Nature 563 (7731): 320–321. ISSN 0028-0836. DOI:10.1038/d41586-018-07267-3.