Bertha Camilla Schütz (known as Maria) was born in Vienna in 1878. A writer and journalist, she followed in her father’s footsteps as collaborator on the Neue Freie Presse, writing theatre reviews and historical essays. In 1899 she married Wolf Pauli and their first child was born on 25 April 1900. Wolfgang junior, seen here at the age of 20 months, grew up to be a Nobel prizewinning physicist, and his sister Hertha (1906-1973) became an actress and writer. Their mother was a pacifist, a socialist and a feminist, participating in the electoral campaign of 1919 to urge women to cast their newly won vote for the Social Democratic Party. She died (suicide) on 15 November 1927.
From the archive
In October 1918 Wolfgang Pauli left Vienna to study at the University of Munich. His Kollegienbuch gives a glimpse of the lecture courses he followed.
During the first semester Pauli attended a couple of morning courses (Unorganische Experimentalchemie and Experimentalphysik I), but gradually the nightlife of Munich claimed more of his attention. He would return late and continue working through much of the night, developing the habit of dropping in only towards the end of morning lectures to check the blackboard and see what he had missed. Sommerfeld tolerated this from his brilliant student, and Pauli achieved the highest mark in all disciplines at the oral doctoral examination on 25 July 1921.
Wolfgang Pauli, Werner Heisenberg and Enrico Fermi relax on Lake Como during the 1927 International Conference on Physics.
The 1927 conference (held in Como to commemorate the 100th anniversary of the death of Alessandro Volta) is famous for Niels Bohr’s first presentation of his ideas on complementarity. His lecture “The Quantum Postulate and the Recent Development of Atomic Theory” became the basis of the Copenhagen interpretation of quantum mechanics; a fuller version was presented at the Fifth Solvay Conference (Brussels) in October. Bohr had discussed his ideas with colleagues both before and after these conferences, and Pauli was particularly involved in the preparation of the final manuscript.
Despite some reservations about his lecturing style, Wolfgang Pauli was appointed professor of theoretical physics at the ETH, Zürich, on 10 January 1928. He started on 1 April at a basic annual salary of 15,000 francs.
Pauli’s lectures could sometimes be challenging. The equations in this photo (taken in Copenhagen in 1929) look fairly legible, but K. Alex Müller recalls his habit of standing at the centre of the blackboard and writing equations around himself, almost in circles, rather than horizontally. Students in the ETH’s famous lecture room 6c tended to sit in two groups, to his left and his right, in order to be able to see round him! Markus Fierz considered Pauli the sort of teacher whose defect it is to think about their subject while lecturing; consequently, the listener participates in a sort of soliloquy which, since it is not really addressed to him, is sometimes barely intelligible. But - Fierz added - this taught the student, above all, to think critically about a theory.
Among the scientific documents in CERN’s Wolfgang Pauli Archive is a rather unusual item – a copy of the script parodying Goethe’s Faust performed at the Niels Bohr Institute conference, 3-13 April 1932 (exact date of performance not known). Written mostly by Max Delbrück, and decorated with caricatures of the protagonists, the skit features Pauli (Mephistopheles) trying to sell the idea of the neutrino (Gretchen) to a sceptical Paul Ehrenfest (Faust)!
Pauli had postulated the existence of this weightless particle in his famous letter to the ‘Dear radioactive ladies and gentlemen’ at the Tübingen conference in December 1930, but he had to wait until 1956 for experimental confirmation by Reines and Cowan, so in 1932 it was still the subject of debate. Pauli’s reputation for sharp wit made him ideal for his satanic rôle, but in his absence the part was played by Léon Rosenfeld. The rôle of God was assigned to Bohr. The script (in German), can be seen here. An English translation is given in George Gamow’s Thirty Years that Shook Physics.
Wolfgang Pauli is seen here with his former teacher Arnold Sommerfeld attending a conference on the electron theory of metals in Geneva, 15–18 October 1934. The conference proceedings don’t mention any leisure activities, but these included a cable car trip up the nearby Salève mountain to enjoy views of Geneva town, the lake and the Alps. The Salève is in France and Sommerfeld had no French visa, so conference organiser Jean Weiglé obligingly smuggled him up to join the others in his car.
Wolfgang Pauli was awarded the 1945 Nobel prize in physics for his Exclusion Principle. When he received the telegram from Arne Westgren (15 November 1945) Pauli was working at the Institute for Advanced Study in Princeton, having left Europe for the USA during the Second World War. Pauli was the first resident member of the Institute to receive a Nobel prize; his colleagues greeted it with great enthusiasm and the Director organised an official ceremony. Unexpectedly, after speeches by various distinguished guests, Albert Einstein rose to give an impromptu address, referring to Pauli as his intellectual successor. Pauli was deeply touched by this speech, recalling it in a letter to Max Born ten years later (24 April 1955), and regretting that, since it had been entirely spontaneous, no record of it remained.
The date on this menu for Wolfgang Pauli’s Nobel prize festivities is 1946, yet he was awarded the physics prize for his exclusion principle in 1945. In a letter to Niels Bohr (25 November 1945) he explains the delay:
“Dear Bohr! It was a great exciting surprise that the Nobel prize was awarded to me this year although I had thought already a week earlier, when the congratulation telegramm of you and your wife arrived, that it was a good omen … The decision, whether or not I should go to Stockholm on December 10 was really not easy. The American authorities kindly offered me exit and re-enter permits for a trip to Stockholm and back for this very particular purpose. Considering all circumstances of the present situation, particularly the possibility of a delay by such a trip of my getting naturalized, I finally decided to postpone my participation in the ceremony in Stockholm to next year after having heard that Stern and Rabi are doing the same…”
Pauli was working in the USA during the war, and US naturalization was particularly important to him because his application for Swiss nationality had been turned down in 1938 and was not granted until 1949.
“We have just signed the Agreement which constitutes the official birth of the project you fathered at Florence. Mother and child are doing well, and the doctors send you their greetings.” This was the message sent to Isidor Rabi on 15 Feb 1952 by the signatories of an agreement establishing the provisional European Council for Nuclear Research.
Scientists and politicians had been pressing for the creation of a European laboratory to pool resources depleted after World War Two, and Nobel laureate Rabi added his support at the fifth UNESCO General Conference (Florence, June 1950), where he tabled a resolution to “assist and encourage the formation of regional research centres and laboratories in order to increase and make more fruitful the international collaboration of scientists…”
The first resolution concerning the establishment of a European Council for Nuclear Research was adopted at an intergovernmental meeting of UNESCO in Paris in December 1951. The provisional Council, set up in 1952, was dissolved when the European Organization for Nuclear Research officially came into being in 1954, though the acronym CERN (Conseil Européen pour la Recherche Nucléaire) was retained.
Too often trip reports are just boring administrative documents, but this one caused a radical rethink of the design for CERN’s Proton Synchrotron. Suddenly a relatively straightforward engineering challenge became a development project for an untested idea.
Plans were already underway for CERN’s large accelerator, a scaled-up version of Brookhaven’s Cosmotron, when Odd Dahl, Frank Goward and Rolf Wideröe visited Brookhaven in 1952. There they joined in discussions about a new strong-focusing (or alternating gradient focusing) technique, which meant smaller magnets could be used to guide particles round an accelerator provided they were arranged with their field gradients facing alternately inwards and outwards instead of the conventional outward-facing alignment. Dahl recommended laying aside plans for a 10 GeV accelerator for the time being in order to investigate the idea further (CERN-PS-S4).
It was a risky decision to follow this unexplored route, but one that paid off by allowing construction of a much more powerful machine at little extra cost. When the Proton Synchrotron came into operation in November 1959 it had an energy of 24 GeV, later increased to 28 GeV.