Wolfgang Pauli

Wolfgang Ernst Friedrich Pauli was born in Vienna, Austria, on April 25, 1900.⁠[1][2]

His father, Wolfgang Joseph Pauli (1869–1955), was born Pascheles and changed his name to Pauli in 1898. He trained as a physician in Prague and practised in Vienna, converted from Judaism to Roman Catholicism in 1899, married Bertha Camilla Schütz in May of that year, and then gave up medicine for research in chemistry and physics, becoming a university professor.⁠[3][4]

Charles Enz’s article gives the father’s original name as Wolf Pascheles and states that he studied medicine together with one of Ernst Mach’s sons. MacTutor’s biography adds that he became popular as a doctor in Vienna and had been inspired to study science by Mach; the National High Magnetic Field Laboratory’s profile states that after running a medical practice he carried out research in biochemistry and taught at the University of Vienna, and the ETH Library’s online exhibition calls him a well-known doctor and professor of chemistry.⁠[5][4][6][7]

Charles Enz’s centenary article states that the father came from a well-known Jewish family in Prague, attended Ernst Mach’s physics classes while studying medicine and settled in Vienna in 1893; the Dictionary of Scientific Biography describes him as professor of colloid chemistry at the University of Vienna.⁠[5][8]

The American Institute of Physics’ record differs from these sources on the family: its relationship list carries the entry “Pascheles, Wolf, 1814-1857” with the note “Father, and Professor of Physical Chemistry,” and the entry “Mach, Ernst, 1838-1916” with the note “Grandfather and Physicist/Philosopher.”⁠[9]

His mother, Bertha Camilla Schütz (1878–1927), was also known as Maria; the National High Magnetic Field Laboratory’s profile describes her as a writer.⁠[3][6]

He was his parents’ first child. The ETH Library’s short portrait describes his mother as a journalist, and its online exhibition states that she worked as a freelancer for a Vienna newspaper. Her first name is printed as Bertha in the CERN Archives’ authority record, in the ETH Library’s exhibition and in the Universität Hamburg’s article, and as Berta in MacTutor’s biography, the Neue Deutsche Biographie and the ETH Library’s short portrait.⁠[10][7][3][4][11][12]

He was baptized a Catholic, and his godfather was the physicist and philosopher Ernst Mach (1838–1916). The christening took place on May 31, 1900, when Mach gave him a silver cup; his middle name Ernst was chosen in Mach’s honor.⁠[4][8][3]

Enz’s article states that Mach, who had accepted a chair of philosophy at the University of Vienna in 1895, agreed to be the boy’s godfather; BritannicaEncyclopædia BritannicaEncyclopædia Britannica is a general English-language encyclopedia first published in Edinburgh, Scotland, in 1768; the name also refers to its publisher, Chicago-based Encyclopædia Britannica, Inc. (which presents itself as The Britannica Group). The print edition ended in 2012, and the company’s main businesses since then have been the online encyclopedia Britannica.com, digital education products for schools and libraries, and Merriam-Webster dictionaries.Open the full entry’s article calls Mach his godfather and mentor.⁠[5][1]

Britannica’s article notes that he later described Mach’s influence on him as an anti-metaphysical baptism.⁠[1]

Britannica’s article describes him as raised among Vienna’s intellectual elite; the ETH Library’s exhibition states that he grew up in an intellectually very stimulating atmosphere and that a private tutor fostered his early gift for mathematics and science with additional lessons in mathematics. The Neue Deutsche Biographie writes that during his school years his mathematical talent was encouraged by his father and his godfather, and the National High Magnetic Field Laboratory’s profile that his parents’ professions brought the family into contact with many prominent people.⁠[1][7][11][6]

The Neue Deutsche Biographie gives his religion as Catholic, later without denomination. The Dictionary of Scientific Biography notes that, because his father bore the same name, he signed his early papers “Wolfgang Pauli, Jr.”⁠[11][8]

He attended the Döblinger Gymnasium in Vienna and graduated with distinction in July 1918.⁠[13][4]

The ETH Library’s exhibition calls the school the humanistic Döblinger Gymnasium and states that his class was nicknamed the class of geniuses because Richard Kuhn, a later Nobel Prize laureate, was also in it; the CERN Archives show a photograph of the class of 1918 under the same nickname. MacTutor’s biography and the National High Magnetic Field Laboratory’s profile print the school’s name as Döblingen Gymnasium.⁠[7][13][4][6]

At 13 he read Mach’s Mechanics, which Mach had given him with a dedication. Toward the end of his school years he secretly read Albert EinsteinAlbert EinsteinAlbert Einstein (1879–1955) was a German-born physicist who formulated the special theory of relativity in 1905 and the general theory in 1915 and received the 1921 Nobel Prize in Physics for his discovery of the law of the photoelectric effect. From 1933 until his death he was a professor at the Institute for Advanced Study in Princeton, New Jersey, United States.Open the full entry’s general theory of relativity during dull lessons, as he had earlier studied Jordan’s Cours d’analyse.⁠[5][8]

MacTutor’s biography states that he found school boring and hid Einstein’s papers under his desk to read during lessons; the Dictionary of Scientific Biography records his later remark that on reading Einstein’s general theory of relativity it was as if scales had fallen from his eyes. Britannica’s article states that he taught himself the theory of relativity during his Gymnasium years.⁠[4][8][1]

In 1918 he entered the University of Munich to study physics under Arnold Sommerfeld (1868–1951). Within two months of leaving school he had submitted his first paper on the theory of relativity, and in September of that year a study of his on a generalized form of Einstein’s theory drew the attention of specialists.⁠[11][4]

The ETH Library’s exhibition dates his move to Munich to the autumn of 1918 and shows his student card from the University of Munich. Enz’s article states that he published his first paper, on general relativity, at 18, before becoming Sommerfeld’s student; the Universität Hamburg’s article adds that the paper dealt with the gravitational field and that Enz, his biographer and former assistant, described him as a child prodigy. MacTutor’s biography states that he wrote two more articles on relativity as an undergraduate; the ETHistory page written by Monika Burri states that as a first-semester student he gave a talk in Sommerfeld’s famous Wednesday colloquium and that at 19 he published his first scientific papers in the Zeitschrift für Physik.⁠[14][5][12][4][15]

MacTutor’s biography states that Sommerfeld quickly recognized his genius and that Pauli showed more respect for Sommerfeld, both as a person and as a scientist, than for anyone else. Enz’s article states that Sommerfeld saw that the young man could not learn much more from him, and the Universität Hamburg’s article that Sommerfeld called him a “Genius ersten Ranges.” Britannica’s article notes that he distinguished himself not only by his brilliance but also by his exacting rigor and his impertinent witticisms. A photograph in the ETH Library’s exhibition, taken at the metals congress in Geneva in October 1934, shows him with Sommerfeld, whom its caption calls his teacher and mentor.⁠[4][5][12][1][14]

In Munich he also learned the quantum theory of the atom, and Werner Heisenberg (1901–1976) was a fellow student. In June 1920 he wrote his first paper on quantum physics, on the magnetic properties of matter.⁠[8][11][4]

MacTutor’s biography dates Heisenberg’s arrival in Munich to 1920 and gives his description of Pauli as a typical night bird who liked cafés and town life, worked intensely and successfully after his evenings out and, to Sommerfeld’s dismay, rarely attended the morning lectures and did not turn up until about noon. The same biography and the Dictionary of Scientific Biography record that his first encounter with Bohr’s basic quantum postulate came as a shock to him. The Dictionary of Scientific Biography names Heisenberg and Bethe among Sommerfeld’s pupils, and the ETH Library’s exhibition Heisenberg, Peter Debye and Gregor Wentzel.⁠[4][8][14]

Felix Klein had asked Sommerfeld to write the article on relativity for the Encyklopädie der mathematischen Wissenschaften, and Sommerfeld passed the task to Pauli, who was scarcely 20 years old and a student in his fourth semester.⁠[8]

The review appeared in 1921 and ran to 237 pages. Einstein reviewed it and judged that a reader would hardly believe that so mature and grandly conceived a work came from a 21-year-old author; Sommerfeld wrote to Einstein that the article was masterly.⁠[11][4][8]

Sources give the length of the review differently: 237 pages in MacTutor’s biography, about 250 pages in the Dictionary of Scientific Biography, 250 pages on the ETHistory page, and more than 200 pages in the National High Magnetic Field Laboratory’s profile and the Universität Hamburg’s article. The Universität Hamburg’s article states that he wrote it at 19; MacTutor’s biography states that Sommerfeld gave him the task after only two years at university and that the monograph appeared two months after his doctorate.⁠[4][8][15][6][12]

MacTutor’s biography lists what Einstein praised in the work: psychological understanding of the development of the ideas, sureness of mathematical deduction, profound physical insight, a capacity for lucid, systematic presentation, knowledge of the literature, complete treatment of the subject matter and sureness of critical appraisal. The Dictionary of Scientific Biography states that, together with Hermann Weyl’s Raum, Zeit, Materie, it was the first comprehensive presentation of Einstein’s mathematical and physical ideas; Enz’s article calls it still a standard reference and states that it made Pauli famous, and the National High Magnetic Field Laboratory’s profile that it was later published as a monograph and is still considered a preeminent treatise on the subject. The ETHistory page states that Einstein wrote this judgment to Max Born in December 1921, shortly after the article appeared.⁠[4][8][5][6][15]

The review was later reprinted as a book.⁠[16]

In July 1921 he completed his doctoral thesis under Sommerfeld, treating the hydrogen molecule ion with the old quantum theory, and received his doctorate in theoretical physics summa cum laude. The theory failed to account for the empirical properties of this system; the Neue Deutsche Biographie writes that the failure was taken as the first sign of an approaching crisis.⁠[11][4][13]

MacTutor’s biography states that Sommerfeld praised the thesis as showing his full command of the tools of mathematical physics and that Pauli himself was disappointed that its results did not agree with experiment. The ETH Library’s exhibition notes that he took his doctorate after only six semesters, and the CERN Archives hold his Munich course booklet and his attestation of completed courses of October 1921.⁠[4][14][13]

The Dictionary of Scientific Biography gives the thesis title as “Über das Modell der Wasserstoffmolekülions” and dates the doctorate to 1922.⁠[8]

From October 1921 he spent one semester at the University of Göttingen as assistant to Max Born (1882–1970), carrying out quantum-theoretical calculations of several models of the helium atom with perturbation methods developed together with Born; the theory failed again.⁠[11][4][13]

The Universität Hamburg’s article relates, from what Max Born wrote to Einstein, that Pauli liked to sleep late in Göttingen and more than once missed the 11 o’clock lecture, so that the Borns sent their maid to him at 10:30 to make sure that he was up. The ETH Library’s short portrait dates the Göttingen assistantship to the winter semester of 1921–1922.⁠[12][10]

In 1922 he accepted a position offered by Wilhelm Lenz (1888–1957), himself a pupil of Sommerfeld, and became an assistant at the newly founded University of Hamburg.⁠[11][13]

The ETH Library’s pages date his start in Hamburg to the summer semester of 1922, state that he joined his friend Professor Wilhelm Lenz there as a “scientific helper,” that is, an assistant, and note that the University of Hamburg benefited in the 1920s from its closeness to Copenhagen and Göttingen, two centers of theoretical physics. The Neue Deutsche Biographie writes that within a few years Hamburg became a further center of quantum physics through Otto Stern and others and that Pauli had an essential share in this.⁠[17][10][11]

In June 1922 Niels Bohr (1885–1962) gave guest lectures in Göttingen on the periodic system of the elements; Pauli met him there, and Bohr then invited him to Copenhagen for a year.⁠[11][18]

In the autumn of 1922 he went to Copenhagen, where he worked on the anomalous Zeeman effect and generalized Landé’s term analysis to the case of very strong magnetic fields (the Paschen-Back effect); together with Heisenberg he gradually solved the puzzle of the complex line splittings characteristic of the effect.⁠[18][11]

The Neue Deutsche Biographie writes that he received decisive impulses from Bohr, whose lectures he attended in Göttingen in June 1922, and MacTutor’s biography that he described the meeting with Bohr as the beginning of a new phase of his scientific life. Britannica’s article describes his work at Bohr’s institute in Copenhagen in 1922–1923 as a one-year leave. Enz’s article states that in Copenhagen he became a good friend of Bohr’s assistant Hans Kramers, who remarked that Pauli’s heart was better than his wit.⁠[11][4][1][5]

In 1923 he returned to teach at the University of Hamburg. In February 1924 he obtained his habilitation there with a thesis on generalizing the statistical laws in the quantum theory of radiation and gave his inaugural lecture as Privatdozent on the periodic system of the elements; the CERN Archives date the lecture to February 23.⁠[13][13][12][18][19]

He was dissatisfied with the lecture because the problem of the closing of the electron shells remained unsolved. MacTutor’s biography dates his appointment as Privatdozent to 1923.⁠[18][4]

Britannica’s article has him return to Hamburg in 1924 as a lecturer and complete his habilitation in that year, and the American Institute of Physics’ record dates his post as lecturer at the University of Hamburg to 1924. The fonds description of the Pauli Archive at the CERN Archives calls him honorary professor at the University of Hamburg from 1924 to 1928, and the ETH Library’s exhibition states that he was promoted to professor in Hamburg in 1924. Among the documents shown with the CERN Archives’ biography is his nomination as professor at the University of Hamburg, dated 1926.⁠[1][9][20][17][13]

In the autumn of 1924 he rejected the view that the doublet structure of the alkali spectra was due to the angular momentum of the atomic core and attributed it instead to a quantum property of the electron itself, which amounted to giving the electron a fourth quantum number. In his Nobel Lecture he recalled that he had called this property “a two-valuedness not describable classically.”⁠[18][1]

Prompted by a remark in a paper by the English physicist Edmund Stoner, and after checking further conclusions about the anomalous Zeeman effect during a visit to Tübingen, he formulated the general exclusion principle in Hamburg in the spring of 1925: no two electrons in an atom can have the same set of quantum numbers. The paper was published in volume 31 of the Zeitschrift für Physik (1925).⁠[18][6][2][8]

The principle explained the arrangement of atomic electrons in shells and the structure of the periodic table of the elements. The CERN Archives’ biography and the Neue Deutsche Biographie date its formulation to 1924.⁠[11][13]

The paper occupies pages 765–783 of the volume. The Neue Deutsche Biographie formulates the principle as the rule that a stationary state of the atom defined by four quantum numbers can be occupied by at most one electron, and adds that Pauli, following Mach’s positivist standpoint, deliberately avoided model pictures of the atom that experience could not test, a restraint that pointed the way for Heisenberg’s matrix mechanics.⁠[11][11]

In 1925 Samuel Goudsmit and George Uhlenbeck interpreted the fourth quantum number as the spin of the electron. Pauli doubted the idea at first and was later convinced by Thomas’s calculations of the doublet splitting.⁠[6][4][18]

Before formulating the exclusion principle he had also postulated a nuclear spin to explain the hyperfine anomalies in spectra.⁠[5]

MacTutor’s biography dates his proposal of a spin quantum number for electrons to 1924; the Dictionary of Scientific Biography prints Stoner’s name as E. C. Stoner and states that Pauli explained Stoner’s rule by the exclusion principle. Enz’s article notes that the principle was later recognized as responsible for the stability of matter in general, and Britannica’s article that it underlies Fermi-Dirac statistics, quantum chemistry and the quantum theory of solids. The ETH Library’s exhibition states that the principle long remained an addition to quantum theory that could not be explained further and that Pauli needed almost another 15 years to clarify it.⁠[4][8][5][1][21]

Heisenberg discovered matrix mechanics in the summer of 1925. Pauli, then writing a long article on quantum theory for Springer’s Handbuch der Physik, took only an indirect part in this development, but he at once carried out a matrix-mechanical calculation of the hydrogen atom that helped the new theory gain acceptance more quickly; MacTutor’s biography places the calculation before the end of 1925.⁠[11][4]

That article, on the old quantum theory and the correspondence principle, appeared in volume 23 of the Handbuch der Physik in 1926.⁠[8]

Many of his results circulated only orally or in letters, among them his proof that Heisenberg’s mechanics is equivalent to the wave mechanics published by Erwin Schrödinger in January 1926. He also took part in the formulation of Heisenberg’s uncertainty relation, in Born’s probabilistic interpretation of matter waves and in the development of Bohr’s concept of complementarity.⁠[11]

At the end of 1926, building on the exclusion principle, he explained how paramagnetism arises and why it fails to appear among the electrons of metals.⁠[11]

In 1927 he published “Zur Quantenmechanik des magnetischen Elektrons” in volume 43 of the Zeitschrift für Physik, introducing what became known as the Pauli matrices and extending the formalism of quantum mechanics to the spinning magnetic electron; Paul DiracPaul DiracPaul Dirac (1902–1984) was a British physicist and one of the founders of quantum mechanics and quantum electrodynamics. He formulated the relativistic Dirac equation for the electron and predicted antiparticles, was Lucasian Professor of Mathematics at Cambridge from 1932 to 1969, and shared the 1933 Nobel Prize in Physics with Erwin Schrödinger.Open the full entry later developed this into a relativistic theory of the electron.⁠[11][11]

In Hamburg he soon formed friendships with fellow physicists such as Otto Stern (1888–1969), who was appointed there shortly after him, and he had good relations with the astronomer Walter Baade; in 1926 he received the title of professor. In letters he described these years as his “frohen Tage in Hamburg.”⁠[11][12][19]

The ETH Library’s exhibition states that in 1927 he had intensive discussions with Bohr and Heisenberg about what he called, in a letter to Bohr, solving the quantum puzzle, and that the results, known as the Copenhagen interpretation of quantum theory, were presented that year at international conferences in Como and Brussels. Britannica’s article holds that his philosophical analysis played a central role in that interpretation.⁠[17][1]

The Wolfgang Pauli Centre’s page counts among the results of his Hamburg period the work on the anomalous Zeeman effect, on electron spin and the Pauli equation and on the electron gas in metals; the Universität Hamburg’s article quotes the historian of physics Steffen Richter, who counts the Hamburg years as probably among the most fruitful of his life. The same article states that the Hamburg scientists spent their free time together, going to the cinema and to the North Sea, and describes Pauli as a perfectionist and a sociable man who liked to go to pubs and often worked late into the night.⁠[22][12]

On January 10, 1928, he was appointed professor of theoretical physics at ETH Zurich; he took up the post on April 1 with a basic annual salary of 15,000 francs.⁠[23]

The CERN Archives’ page notes that the appointment was made despite some reservations about his lecturing style. The Dictionary of Scientific Biography states that it was the Swiss Board of Education that appointed him Debye’s successor, and the ETH Library’s short portrait that he took up his post at the Institute of Theoretical Physics in early 1928 and worked there with the experimental physicist Paul Scherrer, who largely relieved him of his administrative duties as director of the institute.⁠[23][8][10]

He succeeded Peter Debye and asked for only one condition, a research assistant. The assistantship was held twelve times during his tenure, by Ralph Kronig, Felix Bloch, Rudolf Peierls, Hendrik Casimir and Victor Weisskopf among others; the last holder was Charles Enz.⁠[5]

The Dictionary of Scientific Biography adds that he always gave the assistantship to someone who already held a doctorate. Enz’s article relates of the first assistants that Ralph Kronig explored the night life of Zurich with Pauli and Paul Scherrer; that Felix Bloch later received the Nobel Prize; that Pauli teased Rudolf Peierls, who came from Berlin, for speaking too fast; that he asked visitors to address Hendrik Casimir, later a director at PhilipsPhilipsPhilips (Koninklijke Philips N.V.) is a health technology company founded in Eindhoven, the Netherlands, in 1891 by Gerard Philips and his father, Frederik Philips, and now headquartered in Amsterdam; it was long known for lighting and consumer electronics such as the compact cassette and the CD, and was one of TSMC’s founding shareholders.Open the full entry in Eindhoven, by the title of director, knowing that it annoyed him; and that when Victor Weisskopf published a result for the self-energy of the electron with the wrong sign, he remarked that he should have taken Hans BetheHans Albrecht BetheHans Albrecht Bethe (1906–2005) was a German-born American theoretical physicist who joined Cornell University in 1935, headed the theoretical division at Los Alamos during the Second World War and received the 1967 Nobel Prize in Physics for his work on nuclear reactions and the energy production of stars.Open the full entry instead.⁠[8][5]

Enz, the last of the assistants, writes that the later assistants met with milder criticism, that arranging concert tickets for Pauli and his collaborators was part of the assistant’s duties, and that he once received a card from a Zurich bar in which Pauli complained of having missed a concert by Isaac Stern and closed with the hope of better times.⁠[5]

The Neue Deutsche Biographie also counts Nicholas Kemmer and Markus Fierz among his Zurich students, and the American Institute of Physics’ record lists J. Robert OppenheimerJ. Robert OppenheimerJ. Robert Oppenheimer (1904–1967) was an American theoretical physicist and science administrator who directed the Los Alamos laboratory that developed the atomic bomb during World War II.Open the full entry among those he advised.⁠[11][9]

The same record lists as advised by him at ETH Zurich Konrad Bleuler, Felix Bloch, H. B. G. Casimir, Max DelbrückMax DelbrückMax Delbrück (1906–1981) was a Berlin-born physicist and biologist who worked in the United States at Vanderbilt University and the California Institute of Technology. A pioneer of bacteriophage research and molecular biology, he shared the 1969 Nobel Prize in Physiology or Medicine with Salvador Luria and Alfred Hershey.Open the full entry, Walter M. Elsasser, Eugene Feenberg, Eugene Guth, Josef M. Jauch, N. Kemmer, R. Kronig, Edgar Luscher, K. A. Müller, Rudolf E. Peierls, Heinrich Rohrer, L. Rosenfeld, Armin Thellung and Victor Frederick Weisskopf; at Princeton UniversityPrinceton UniversityPrinceton University is a private university and Ivy League member in Princeton, New Jersey. Chartered on October 22, 1746 as the College of New Jersey, it moved to Princeton in 1756 and adopted its present name in 1896. Undergraduate education leads to A.B. and B.S.E. degrees and emphasizes small-group discussion, independent research and residential college life. Graduate education spans the humanities, social sciences, natural sciences and engineering. As of October 2026, Christopher L. Eisgruber was president. Its 2026–27 operating budget was $3.407 billion, including $342 million for undergraduate aid.Open the full entry Kalervo Vihtori Laurikainen and Maurice Pryce; at the University of Hamburg H. Zanstra; and at the University of Vienna F. R. Eirich. It names Arnold Sommerfeld as his advisor at Munich, Max Born and Niels Bohr as his PhD advisors at Göttingen and Copenhagen respectively, Wilhelm Lenz as his research advisor and Paul Scherrer as a research colleague.⁠[9]

After Schrödinger left the University of Zurich he was succeeded by Gregor Wentzel, with whom Pauli ran a joint seminar for many years; Britannica’s article credits the two with creating a successful school of theoretical physics in Zurich.⁠[8][1]

The Neue Deutsche Biographie writes that in Zurich he built up one of the most important centers of theoretical physics in the world and that his students helped to found modern nuclear, field and elementary-particle physics; the National High Magnetic Field Laboratory’s profile states that he helped to make ETH Zurich one of the best institutions for theoretical physics in the world. A photograph on the ETHistory page shows him in the Swiss mountains in the 1930s with the mathematicians Georg Pólya of ETH Zurich and Erich Hecke of Hamburg.⁠[11][6][15]

He was the only lecturer in theoretical physics at ETH Zurich, and his lectures were known to be hard to follow. K. Alex Müller recalled that he stood at the center of the blackboard and wrote the equations around himself almost in circles, so that students in lecture room 6c sat in two groups to his left and right; Markus Fierz held that his habit of thinking about the subject while lecturing made the lectures at times barely intelligible but taught students to think critically about a theory.⁠[8][23]

Fierz writes in the Dictionary of Scientific Biography that Pauli was never what one would call a good lecturer, that he mumbled to himself and that his writing on the blackboard was small and disorganized, but that his students were nevertheless fascinated and greatly stimulated.⁠[8]

In 1929–1930 he and Heisenberg together laid the foundations of a general quantum field theory, in which elementary particles appear as field quanta that can be created and destroyed.⁠[11]

On May 6, 1929, he left the Roman Catholic Church.⁠[4]

On December 23, 1929, he married Käthe Margarethe Deppner in Berlin; Britannica’s article describes her as a Berlin dancer, and the Neue Deutsche Biographie gives her full name as Luise Margarete Käthe Deppner. They were divorced in Vienna on November 29, 1930.⁠[4][1][11]

MacTutor’s biography states that his reasons for leaving the Church are not entirely clear and that the marriage was never a success, even in its first months. The ETH Library’s short portrait calls his first wife the Berlin dancer Käthe Deppert and dates the marriage to December 1929 and the divorce to a year later; the CERN Archives’ biography states that the marriage lasted less than a year. Enz’s article states that at the beginning of his professorship at ETH Zurich he developed a neurosis and remarked to Gregor Wentzel that with women things were not going well for him at all.⁠[4][10][13][5]

On December 4, 1930, he wrote a letter that was sent by way of Lise Meitner to a conference in Tübingen. It proposed that in nuclear beta decay a neutral particle is emitted along with the electron, which would explain the continuous beta spectrum; at that time he called the particle a neutron. Ludmil Hadjiivanov’s historical survey describes it as an open letter written in Zurich to the participants in the Tübingen meeting and quotes its statement that the particles have spin 1/2 and obey the exclusion principle.⁠[8][13][24][25]

In the letter he excused his absence from the meeting on the ground that he had to attend a dance in Zurich.⁠[24]

The CERN Archives’ page gives the letter’s salutation, in English translation, as addressed to the radioactive ladies and gentlemen. The Neue Deutsche Biographie places the postulate in the context of his work of 1929–1930 on quantum field theory, while MacTutor’s biography and the National High Magnetic Field Laboratory’s profile date the prediction to 1931.⁠[24][11][4][6]

Bohr then thought that in beta decay the conservation of energy might hold only statistically, whereas Pauli held to the conservation laws.⁠[8]

On June 16, 1931, he made the idea public at a conference in Pasadena. Hadjiivanov’s review states that this was the meeting of the American Physical Society, that the idea was met with skepticism there, and that in October of that year he discussed it with Enrico FermiEnrico FermiEnrico Fermi (1901–1954) was an Italian-American physicist who received the 1938 Nobel Prize in Physics and in 1942 led the team that achieved the first controlled nuclear chain reaction in Chicago.Open the full entry at the nuclear physics conference in Rome.⁠[4][25]

MacTutor’s biography adds that The New York TimesThe New York TimesThe New York Times is an American morning daily newspaper published in New York City. Founded in 1851, it is published by The New York Times Company.Open the full entry of June 17 carried the announcement, stating that Pauli postulated particles which he called neutrons and describing them as a new inhabitant of the heart of the atom, and that he was still unsure of the particle’s properties and did not put the prediction into print until 1933. Hadjiivanov’s review states that Fermi was immediately attracted by the idea.⁠[4][25]

In 1931 he was a visiting professor at the University of MichiganUniversity of MichiganThe University of Michigan is a university founded in Detroit in 1817 that moved to Ann Arbor, Michigan, in 1837; it is governed by a statewide-elected Board of Regents and also has campuses in Dearborn and Flint.Open the full entry.⁠[4]

Chadwick discovered the neutron in 1932. At the Solvay Congress of 1933 Pauli again justified his proposal at length, and the justification was printed in the congress report; Hadjiivanov’s review and the ETH Library’s short portrait identify it as the seventh Solvay Conference, held in Brussels in October 1933; Hadjiivanov’s review states that Pauli used the name neutrino there, and the ETH Library’s short portrait treats this congress as the first public presentation of the hypothesis. MacTutor’s biography adds that in the text he published in 1933 he took the particle to have zero mass.⁠[4][25][8][10]

On the origin of the name neutrino, the CERN Archives state that Fermi coined it in 1933 and MacTutor’s biography that Fermi named the particle in 1934, while Hadjiivanov’s review holds that the word was first pronounced by Edoardo Amaldi.⁠[24][4][25]

Hadjiivanov’s review takes the Amaldi story from a recollection of Occhialini quoted in a review by Amaldi of 1984: the word came up in a humorous conversation at the Istituto di Via Panisperna, where Amaldi used the name jokingly to distinguish Pauli’s particle from Chadwick’s neutron, and Fermi began to use it sometime between the conference in Paris in July 1932 and the Solvay Conference of October 1933. MacTutor’s biography adds that in 1934 Fermi correctly stated that the neutrino is not a constituent of the atomic nucleus, and the Dictionary of Scientific Biography that Pauli presented the history of the discovery in a lecture before the Naturforschende Gesellschaft in Zurich in 1957.⁠[25][4][8]

Fermi’s theory of beta decay followed in 1934.⁠[8]

In 1933 his article “Die allgemeinen Prinzipien der Wellenmechanik” appeared in volume 24, part 1, of the Handbuch der Physik. The Dictionary of Scientific Biography refers to his 1926 Handbuch article as the Old Testament and to this one as the New Testament; the latter was used unchanged in the new handbook of 1958.⁠[8]

The ETHistory page likewise applies the two names to the Handbuch articles of 1926 and 1933 and attributes them to insiders, whereas the National High Magnetic Field Laboratory’s profile states that physicists called the chapter of 1933 on wave mechanics the New Testament and his earlier chapter on relativity the Old Testament. The Dictionary of Scientific Biography quotes Hermann Weyl’s praise of the 1933 article: what Pauli had written on wave mechanics was again completely outstanding.⁠[15][6][8]

After the failure of his first marriage he went through a severe personal crisis. The CERN Archives’ biography states that he underwent psychoanalytic treatment with Carl Gustav Jung (1875–1961) from 1932 to 1934, at first mainly in contact with Jung’s student Erna Rosenbaum.⁠[13][11]

Britannica’s article states that an analyst was recommended to him by Jung and that he ended two years of personal therapy with Jung in 1934. MacTutor’s biography states that he began drinking and for that reason consulted Jung, that he was treated not by Jung but by one of Jung’s assistants, and that he described more than a thousand dreams, which he sent to Jung over many years and on some of which Jung published work. Charles Enz’s article states that the two met in Zurich in 1932 and that three years of psychoanalysis followed.⁠[1][4][5]

He and Jung corresponded for many years afterward, and he tried to interpret Jung’s ideas on the relation between consciousness and the collective unconscious as a complementary relation in Bohr’s sense.⁠[1][11]

The CERN Archives’ biography adds that the suicide of his mother had aggravated the crisis and that he and Jung remained friends and published together on various topics; the ETH Library’s short portrait states that Jung referred him to a young colleague, Erna Rosenbaum, for treatment, and the American Institute of Physics’ record notes of Jung that he conducted psychoanalysis and recommended therapy to Pauli. The Universität Hamburg’s article has Jung treat him for several years from 1930 and states that Jung later published the analyses, without naming him, in “Psychologie und Alchemie,” and that the second marriage ended the crisis. The National High Magnetic Field Laboratory’s profile speaks of a depression severe enough for him to seek Jung’s help.⁠[13][10][9][12][6]

The ETHistory page states that Jung, then a Privatdozent at ETH Zurich, whom Pauli consulted during a life crisis in the early 1930s, arranged a dream analysis with one of his female trainees; that after the therapy was broken off the two kept up a long correspondence; that this dialogue prompted Pauli to keep records of his dreams and that in 1936 Jung, with Pauli’s consent and preserving his anonymity, wrote an essay on dream symbols of the process of individuation based on a series of more than 400 of his dreams, on the theme of the creation of a new center of the personality. Enz’s article relates that Jung noticed the archaic material in his frequent dreams, that Pauli wrote his dreams down from then on and that the two exchanged ideas until nearly the end of Pauli’s life. The ETHistory page draws on two of his letters to Jung: on June 3, 1940, he wrote that external circumstances led him to send the enclosed dream material from the years 1937–1939 so that it would not be lost, and on June 16, 1948, he described the “Pauli effect” of a flower vase that fell over at the founding of the C. G. Jung Institute, after which he at once had a vivid impression that he should, in the symbolic language learned from Jung, pour out water inside, and enclosed an essay that, he wrote, was the result.⁠[15][5]

On April 4, 1934, he married Franciska (Franca) Bertram.⁠[4][13]

Britannica’s article describes psychoanalysis as at first a therapy and then a philosophical interest for him and states that through the study of Jung’s ideas he moved away from positivism. MacTutor’s biography states that he clearly believed in psychology as much as in physics, that he wrote to Pais that in the science of the future reality would be neither “psychic” nor “physical” but somehow both and somehow neither, and that the second marriage, unlike the first, was a great support to him; it quotes his widow, whom it names Franciska Pauli, as saying that he was very easily hurt and therefore let down a curtain, that he tried to live without admitting reality, and that his unworldliness came from his belief that this was possible.⁠[1][4]

In 1935–1936 he was a visiting professor at the Institute for Advanced Study in Princeton, New JerseyNew JerseyNew Jersey is a state in the eastern United States on the Atlantic Ocean, bordered by New York State, Delaware, and Pennsylvania, with the Hudson River forming its northeastern boundary and the Delaware River its western boundary; its capital is Trenton and its largest city is Newark. One of the original 13 colonies, it became the third state to ratify the U.S. Constitution on December 18, 1787, and its population in the 2020 census (April 1, 2020) was 9,288,994.Open the full entry, United StatesUnited StatesThe United States is a federal country in North America made up of 50 states, the District of Columbia as the seat of government, and territories such as Puerto Rico and Guam; its capital is Washington, D.C. The Continental Congress adopted the Declaration of Independence on July 4, 1776. The 2020 census (April 1, 2020) counted a resident population of 331,449,281, and the 435 seats of the House of Representatives are apportioned among the states on the basis of the census.Open the full entry. The Institute’s history page dates his joining its group of scholars to 1935, a year after Paul Dirac.⁠[4][9][26]

He attended the All-Union physics conferences held in Moscow in 1937 and in Odessa in 1939.⁠[4]

After Germany annexed Austria in 1938 he became a German citizen. Britannica’s article notes that his paternal grandparents were Jews and links his acceptance of a visiting professorship in Princeton in 1940 to the possible threat of Nazi persecution; the National High Magnetic Field Laboratory’s profile states that he twice applied unsuccessfully for Swiss citizenship.⁠[4][1][6]

A post by Christian John Huber on ETHeritage, the blog of the ETH Library’s archives, sets out the first application from the files of the ETH Zurich University Archives. Pauli, an Austrian citizen and a baptized Catholic, counted under the Nuremberg race laws as a Jewish “Mischling,” a person of mixed descent; taking German citizenship was out of the question for him, and he at once applied for naturalization in Zurich, but the application was rejected at the end of April 1938 on formal grounds. In his letter of November 9, 1939, to Arthur Rohn, president of the Swiss Federal School Board, Pauli wrote that he had come to Zurich in April 1928 as an Austrian citizen with right of domicile in Vienna, on his appointment as full professor at ETH; that before moving to Zollikon he had asked Zurich’s mayor, Dr. Klöti, by letter whether he could submit a naturalization application; and that Klöti had declined in view of his then only ten years’ residence in Zurich, since a newer law of the city required twelve years of residence for naturalization there.⁠[27]

On May 23, 1938, he moved to the municipality of Zollikon. After the rejection he reluctantly obtained his German passport; the German consulate counted him among the “Halb-Ariern” (half-Aryans), so that he was spared the J stamp, as he informed Frank Aydelotte in Princeton. His father, a professor of biological-physical chemistry who had retired in 1934, counted under the race laws of the Third Reich as a full Jew; Huber writes that it was thanks among other things to the help of Arthur Rohn, president of the Swiss Federal School Board, that Pauli was able to bring him from Vienna to Switzerland, and the ETH Library’s exhibition that this was owed to the efforts of professorial friends and of Rohn and that the father obtained the possibility of working at the University of Zurich.⁠[27][28]

In the letter of November 9, 1939, he also asked whether an application had any prospect of being examined despite the war, and after an encouraging reply from Rohn he applied again at the end of 1939, this time directly to the Police Division of the Federal Department of Justice and Police in Bern. Rohn, who was under pressure because Pauli had received an offer of a guest semester from Princeton, asked the division to deal with the application quickly and added a recommendation for naturalization, which, Huber surmises, had if anything a negative effect on the decision; three weeks later Pauli received a rejection from the head of the Police Division, Heinrich Rothmund. Rohn at once asked for the concrete reasons. Rothmund’s reply to him, dated July 16, 1940, spoke of foreigners who had not yet fully adapted to the Swiss character and national ways, stated that Pauli had come to Zurich in the spring of 1928 as a representative of German science, and held that his opposition to the political development in the Reich did not yet make him Swiss. At the School Board meeting of March 30, 1942, Rohn stated that the application had been rejected, despite the board’s recommendation, on the ground that Pauli was a “nicht assimilierbarer Ostjude.” Huber notes that Rothmund’s statement of reasons contains no explicitly antisemitic argument and finds that a latent racism nevertheless suggests itself between the lines; the ETH Library’s exhibition states that the application was rejected because he did not satisfy the requirement of assimilation and that this deeply offended him. Huber compares the case with that of Albert Einstein, who was naturalized in Switzerland without difficulty in 1901 after little more than five years of residence.⁠[27][28]

MacTutor’s biography states that, fearing that fascism might bring about the end of scientific life in Europe, he encouraged scientific work in the United States and the Soviet Union and urged scientists who were able to remain in Italy and Germany to do so, in the belief that this would preserve scientific culture after the war, and that his German citizenship made his position awkward once war broke out in 1939. The National High Magnetic Field Laboratory’s profile has him leave ETH Zurich in 1938 because Nazi-controlled Germany had annexed Austria, rendering him a German citizen, and adds that, although raised a Roman Catholic, he had Jewish roots, which made him a possible target of persecution by the Germans.⁠[4][6]

In July 1940 he and his wife left Europe for the United States, where he became a visiting professor at the Institute for Advanced Study.⁠[13]

The ETH Library’s exhibition describes his situation after the annexation of Austria as precarious: had Germany occupied Switzerland, he would have been treated as a Jew under German law, and for this reason he accepted a guest professorship at Princeton, for which ETH Zurich granted him six months’ leave in June 1940. Huber’s second post records that the School Board of ETH Zurich had approved his request for leave on June 20, 1940, for a visiting professorship at Princeton in the winter semester of 1940–1941; he had also been invited to a congress at Columbia UniversityColumbia UniversityColumbia University, formally Columbia University in the City of New York, is a private research university in New York City and a member of the Ivy League. Founded in 1754 by royal charter from King George II as King's College, it is the oldest institution of higher education in New York State and the fifth oldest in the United States. It was renamed Columbia College in 1784 and adopted the university name and moved to Manhattan's Morningside Heights in 1896. It has 17 schools and four affiliated colleges, with 35,978 students enrolled in fall 2025. Legal scholar Jennifer L. Mnookin became president on July 1, 2026.Open the full entry in New York in September 1940. MacTutor’s biography and the American Institute of Physics’ record describe his position from 1940 as the chair of theoretical physics at Princeton, and the National High Magnetic Field Laboratory’s profile states that he joined the faculty of Princeton University.⁠[29][4][9][6][28]

Huber’s second ETHeritage post follows his dispute with ETH Zurich through the minutes of the School Board. At its meeting of April 9, 1941, the board extended the leave by a whole year; his teaching had to be taken over by a colleague from the University of Zurich, whom the ETH Library’s exhibition names as Gregor Wentzel. In the autumn of 1941 Scherrer drew the president’s attention to the disadvantage of Pauli’s long absence for physics research and teaching at ETH Zurich, and in a letter of October 21, 1941, the president asked him to resume teaching if at all possible at the beginning of the summer semester of 1942, and at the latest at the beginning of the winter semester of 1942–1943, adding that, should he decide to stay in the United States, the board would have to envisage filling his chair again by October 1, 1942, at the latest; at the meeting of February 13, 1942, it was recorded that he had not yet replied. The post dates the entry of the United States into the war to December 7, 1941; at the meeting of February 13 the board granted a further leave for the summer semester of 1942. In a letter to the board’s president dated January 14, 1942, Pauli declared that he was gladly willing, as far as it depended on his own free will, to fulfill his contract with ETH Zurich, that is, to resume his teaching, but that carrying out his return journey unfortunately did not depend on his free will alone: he did not hold a Swiss passport, with which a return was possible even then, and the British and American authorities treated him as a national of a belligerent enemy state who was of military age; he added that the president, evidently unaware of the situation, had not taken this fact into account in his letter.⁠[29][28]

In September 1942 he was notified that he would not be re-elected after his current term ended at the end of March 1948, on the reasoning that if he returned only after the war his moral authority as a university teacher would undoubtedly be much weakened. In a letter of April 14, 1943, Pauli threatened disciplinary proceedings, and in July 1943 the board discussed opening negotiations with him to dissolve the contract before 1948; a further extension of the leave was carried only narrowly, by the casting vote of the board’s president. The ETH Library’s exhibition states that ETH Zurich tried to persuade him to return and threatened to end his employment, that he dug in his heels, saying that he would like to have attended to his duties but was prevented by aggravating circumstances, and that it was predictable that as the national of a belligerent country he could not return to Switzerland during the war; it adds that Federal Councillor Philipp Etter also associated himself with this view and objected in principle to suspending him from his post.⁠[29][28]

After Germany’s capitulation, at the meeting of June 2, 1945, Rohn pointed out that a difficult situation would arise if Pauli returned, taught for three years and was then not re-elected in 1948, and proposed asking the Federal Council to pay his salary until the end of March 1948 even if he did not lecture; the responsible Federal Councillor, Philipp Etter, replied in a letter of September 13, written in French, that it was neither legally nor financially possible to prevent Pauli from occupying his chair and teaching, since he was a regularly appointed professor, and that, just as there was no sufficient reason to withdraw his salary before 1948 if he could settle in Zurich again, there was no reason to prevent him from teaching until March 1948 if he demanded to exercise the office to which he had been appointed and for which he would be paid. On November 10, 1945, a letter from Pauli to his colleague Paul Scherrer dated July 14, 1945, was read to the board: the Institute in Princeton had now officially offered him the professorship left vacant by Einstein’s retirement on grounds of age; his colleagues there and its director had set him no deadline and agreed with him that it was his duty to travel to Switzerland first, since he had declared for five years that he would return; and he asked whether scientific motives again decided matters at the Swiss universities or whether these had definitively become “eine Art Unterabteilung der Fremdenpolizei,” with Rothmund as de facto rector and School Board president Rohn as the official “Serenissimus.”⁠[29]

In 1940 he formulated the spin-statistics theorem, which links a particle’s spin to its statistical behavior and was published during his Princeton years; in the United States he worked mainly on meson theory.⁠[1][5]

He was a visiting professor at the University of Michigan in 1941 and at Purdue University in 1942.⁠[4][9]

The Neue Deutsche Biographie notes that during the war he and Einstein were among the few eminent physicists who did not have to take part in war research.⁠[11]

The Universität Hamburg’s article states that he declined to do war-related research and refused to join the American atomic weapons program. The CERN Archives hold his certificate of registration as a resident of the United States from 1942 and a photograph taken at Princeton on his 45th birthday in April 1945. Enz’s article calls the paper on the spin-statistics theorem probably his most brilliant.⁠[12][13][5]

In November 1945 a telegram from Arne Westgren dated November 15 informed him that he had been awarded the 1945 Nobel Prize in Physics “for the discovery of the Exclusion Principle, also called the Pauli Principle.” He was the first resident member of the Institute for Advanced Study to receive the prize.⁠[30][2]

MacTutor’s biography states that Einstein had nominated him. The Nobel Prize website gives his affiliation at the time of the award as Princeton University.⁠[4][2]

At the award ceremony on December 10, 1945, the presentation speech was given by Professor I. Waller, a member of the Nobel Committee for Physics. Pauli could not be present, and the prize was handed to Mr. Ravndal, chargé d’affaires of the United States legation, on his behalf.⁠[31][31]

He received the prize unshared. The presentation speech asks Mr. Ravndal to receive it on Pauli’s behalf from the hands of His Majesty. The CERN Archives also hold Westgren’s official letter of November 1945 confirming the award, and on November 17, 1945, a telegram reached ETH Zurich asking for information about the new laureate.⁠[2][31][13][29]

The speech explained that four quantum numbers are in general needed to define the energy state of an electron and that each completely defined state can hold at most one electron; it described the principle as indispensable for explaining the chemical and physical properties of the elements, the electrical conductivity of metals and the magnetic properties of matter, and as later found to hold for protons and neutrons as well.⁠[31]

On the same day a ceremony in his honor was held at Princeton, organized by the Director of the Institute. After the speeches of the guests Einstein gave an unplanned address in which he called Pauli his intellectual successor; Pauli recalled the occasion in a letter to Max Born of April 24, 1955, regretting that no record survived of a speech that had been entirely spontaneous.⁠[4][30]

The CERN Archives’ page adds that Pauli was deeply touched by Einstein’s speech. Enz’s article relates that Einstein rose unexpectedly to propose a toast and designated him his spiritual son and his successor at the Institute; the Universität Hamburg’s article prints the expression as “geistigen Sohn”; the National High Magnetic Field Laboratory’s profile states that Einstein gave the final oration and called him his scholarly successor, and attributes his absence from Stockholm to the war. The ETH Library’s exhibition states that many prominent people were invited to a large official ceremony, calls the spontaneous address by Einstein, in which he described Pauli as his intellectual successor, its climax and shows a photograph of the celebrations in Princeton.⁠[30][5][12][6][32]

In January 1946 he obtained United States citizenship; later that year he returned to Zurich to resume his professorship at ETH Zurich, and he kept up his links with Princeton afterward.⁠[20][13][3]

The ETH Library’s pages state that Princeton proposed him as Einstein’s successor and that Columbia University in New York also offered him a professorship, that declining these offers was not easy for him, and that the growing influence of the military on physics research in the United States, which he opposed as an advocate of free science, weighed heavily in the decision; nobody in Zurich had seriously reckoned with his return, and his colleagues and the School Board were all the more surprised when in April 1946 he kept his promise to take up his chair again. MacTutor’s biography states that he always felt European and never fully fitted into life in the United States, and the Dictionary of Scientific Biography that he returned to Zurich after careful consideration.⁠[10][32][4][8]

Huber’s post states that Pauli arrived back in Switzerland in the first half of April 1946 and that Rohn, because of a short holiday, could receive him only on April 23, 1946; Rohn stated that he was astonished at the change in his character and attitude and found him strangely mild and modest in manner. Pauli set two conditions for staying at ETH Zurich: prompt naturalization and reappointment for ten years, and the president made considerable efforts to meet them. Ernst Bärtschi, the board member who had criticized him most sharply throughout the affair, remarked that the experience so far would have suggested letting him go, had he not received the Nobel Prize since leaving and had an inner change not really taken place in him, and added: “Ich kann nicht beurteilen, ob er durch die Verleihung des Nobelpreises assimilierbarer geworden ist!” Huber holds that the quick easing of the conflict can be explained only by the fact that Pauli had meanwhile received the Nobel Prize, and notes that Pauli was finally naturalized in 1949.⁠[29]

On December 13, 1946, he delivered his Nobel Lecture, “Exclusion Principle and Quantum Mechanics,” in Stockholm.⁠[33][18]

The CERN Archives hold his permit of February 1946 to leave the United States for the Nobel lecture tour and two menus from the Nobel banquet and dinner of December 1946; Enz’s article states that he went to Stockholm only in 1946, on his way back to Zurich. The ETH Library’s exhibition states that he resumed teaching and research in the summer semester of 1946 and moved back into the house in Zollikon in October.⁠[13][5][34]

After his return to Zurich his institute became a world center of quantum field theory, and he worked with students on renormalization in quantum electrodynamics.⁠[5][1]

The ETH Library’s exhibition describes the following years: he led a group of about ten theoreticians and drew physicists from all over the world, which added to the shortage of space at the Physics Institute; in 1950 he became head of department for two years; at his suggestion ETH Zurich created an assistant professorship of theoretical physics, filled in 1955 by his former assistant Res Jost; and at the end of the 1950s he took an active part when three further full professorships of physics were established. He took part in the preparatory meetings for CERN, of which Paul Scherrer was the driving force on the Swiss side. Before 1952 the old physics building was extended and a new one was built to house the cyclotron facility constructed under Scherrer’s direction.⁠[34]

The Dictionary of Scientific Biography states that he lived happily with his wife in Zollikon, near great forests that invited meditative walks.⁠[8]

He later returned to the Institute for Advanced Study as a visitor; its member record lists the spring terms of 1954 and 1956.⁠[35]

The same exhibition records a visit to India in 1952 and visiting professorships at Princeton in 1954, 1956 and 1958, and notes that he took several leaves of absence, some of them during the semester, when his assistants gave his lectures; the Institute for Advanced Study’s member record lists, besides the two dated terms, three further memberships without dates. Britannica’s article adds that in these years he kept up his exchanges with Einstein and Bohr. A photograph in the exhibition, taken at a meeting of Nobel Prize laureates in Lindau, is captioned as his “Maikäferrede.”⁠[34][35][1][32]

In July 1949 he became a Swiss citizen. Two documents of the CERN Archives give different dates: the biography page has July 25, the fonds description of the Pauli Archive July 15.⁠[13][20]

On his nationality, the header of Britannica’s page labels him an American physicist, while the article itself begins by calling him an Austrian-born physicist and states that he became an American citizen in 1946 and finally a Swiss citizen in 1949; the CERN Archives’ authority record writes that on July 25, 1949, he also became a Swiss citizen.⁠[1][3]

In 1952 he and Jung published the volume Naturerklärung und Psyche with Rascher; it contains his essay “Der Einfluss archetypischer Vorstellungen auf die Bildung naturwissenschaftlicher Theorien bei Kepler,” on the influence of archetypal ideas on the formation of Johannes Kepler’s scientific theories.⁠[11][16][8]

Britannica’s article notes that his interest in philosophy grew in his later years and that he sought to understand physis and psyche as complementary aspects of the same reality.⁠[1]

The CERN Courier article describes him as deeply interested in psychology and dreams and convinced that science could not answer every question; in “Die Klavierstunde,” a long letter to Marie-Louise von Franz, he linked dreams and physics.⁠[16]

MacTutor’s biography quotes Laurikainen as writing that in the last 10 to 15 years of his life he spent much time studying the history and philosophy of science and that, starting from the philosophy of quantum mechanics, this led him to psychology, the history of ideas and many other fields, not least the relation of religion to natural science; the ETHistory page adds that he studied Asian doctrines of salvation and Jewish number mysticism and explored the beginnings of the scientific world view in the 17th century. Enz’s article states that he devoted much time to the archetypal background of physical ideas, exemplified by Johannes Kepler, on whom he wrote an important essay; Fierz writes that he took up Jung’s ideas in order to understand better the meaning of scientific activity and that it was always his hope that physics would indicate the mysterious harmony of God and Nature.⁠[4][15][5][8]

In 1955 he published “Exclusion Principle, Lorentz Group and Reflection of Space-Time and Charge,” dedicated to Bohr on his seventieth birthday. Starting from investigations by Schwinger and Lüders, he showed that every Lorentz-invariant Lagrangian field theory is invariant under the combined reflection of charge, space and time, a result that became known as the CPT theorem.⁠[11][8]

The paper appeared on pages 30–51 of the volume Niels Bohr and the Development of Physics (1955), which Pauli edited. Enz’s article states that he turned to symmetries in the mid-1950s, again guided by dreams; Fierz writes that when he conjectured a hidden motive behind the work, Pauli denied it and said that he was interested in these symmetries in their own right. Britannica’s article lists the work on CPT symmetry among his research after the return to ETH Zurich.⁠[11][5][8][1]

On June 14, 1956, Frederick Reines and Clyde Cowan sent him a telegram announcing that they had detected neutrinos; almost 26 years had passed since he put forward the hypothesis. Hadjiivanov’s review states that the telegram was sent from Los Alamos and began with the words “We are happy to inform you that we have definitely detected neutrinos from fission fragments.”⁠[24][25]

Hadjiivanov’s review states that he replied the next day: “Thanks for message. Everything comes to him who knows how to wait.” The CERN Archives add that the reply apparently never arrived and that it survives only as the draft sent by a secretary.⁠[25][24]

In Hadjiivanov’s quotation the first sentence of the telegram goes on to say that the neutrinos were detected by observing inverse beta decay of protons. The National High Magnetic Field Laboratory’s profile dates the first experimental detection of the neutrino to the late 1950s.⁠[25][6]

The Neue Deutsche Biographie calls the detection a final high point of his scientific career.⁠[11]

In 1956 Tsung-Dao LeeTsung-Dao LeeTsung-Dao Lee (1926–2024) was a Shanghai-born American physicist who taught for decades at Columbia University. In 1956 he and Chen Ning Yang proposed that parity might not be conserved in weak interactions, for which they shared the 1957 Nobel Prize in Physics; from the 1970s he helped advance high-energy physics and the training of physicists in China.Open the full entry and Chen Ning YangChen Ning YangChen Ning Yang (1922–2025) was a theoretical physicist born in Hefei, Anhui, China, who shared the 1957 Nobel Prize in Physics with Tsung-Dao Lee for their investigation of the parity laws. In 1954 he and Robert L. Mills formulated non-Abelian gauge theory (Yang–Mills theory), and he worked in turn at the Institute for Advanced Study, Stony Brook University and Tsinghua University.Open the full entry proposed that parity might not be conserved in weak interactions. Pauli was skeptical and regarded such ideas as mere mathematical play.⁠[36][37]

In January 1957, while writing to Victor Weisskopf, he put his doubt in the words “Ich glaube aber nicht, daß der Herrgott ein schwacher Linkshänder ist.” Hadjiivanov’s review states that he still held to parity conservation as late as January 17, 1957, and quotes a letter to Weisskopf in which he declared himself ready to bet a very large sum that the experiments would give symmetric results.⁠[36][25]

Two days later, after Chien-Shiung WuChien-Shiung WuChien-Shiung Wu (1912–1997) was a Chinese-born American experimental physicist who spent most of her career at Columbia University and worked on the Manhattan Project. Her cobalt-60 beta-decay experiment of 1956–1957, carried out with collaborators, provided the first experimental proof that parity is not conserved in weak interactions.Open the full entry’s initial data indicated that the two were right, he wrote in a second note: “Sehr aufregend. Wie sicher ist die Nachricht?”⁠[36]

On January 19, 1957, he wrote to Chien-Shiung Wu, “I congratulate you (to the contrary of myself)”; Hadjiivanov’s review quotes the same letter as saying that he had not believed in parity nonconservation when he read the paper of the two theorists.⁠[37][25]

Hadjiivanov’s review quotes a letter to Weisskopf in which he recounted that on Monday the 21st, at 5 p.m., he received three experimental papers, those of Chien-Shiung Wu, Lederman and Telegdi.⁠[25]

In the same letter, as Hadjiivanov’s review quotes it, he was due to give a lecture on the theory of the neutrino at 8 p.m. that Monday. The National Academy of Sciences’ memoir of Chien-Shiung Wu states that he yielded to the experimental evidence, and Enz’s article describes his turn to symmetries in the mid-1950s as like a presentiment of the sensational news of parity violation in weak decays that came in January 1957. The APS News article places the writing of the letter to Weisskopf in Zurich and describes his handwriting as an untidy scrawl.⁠[25][37][5][36]

The Dictionary of Scientific Biography records that the loss of equal status for left and right at first seemed extraordinarily repugnant to him and that he then recognized that the CPT invariance he had proved still held.⁠[8]

In 1957 he traveled to Israel by plane with Chien-Shiung Wu and afterward wrote to his sister that she was as obsessed with physics as he had been in his young years.⁠[37]

In the last year of his life he was for a time carried away by Heisenberg’s “world formula,” a non-linear Dirac equation with an internal symmetry; on recognizing the shortcomings of the approach he soon withdrew in disappointment.⁠[5]

In 1958 he received the Planck Medal of the Deutsche Physikalische Gesellschaft, and shortly before his death the University of Hamburg awarded him an honorary doctorate.⁠[11][12]

On December 15, 1958, he died of cancer at the Red Cross Hospital in Zurich, aged 58.⁠[20][2]

The National High Magnetic Field Laboratory’s profile states that he was seized by sudden violent pain during a lecture in 1958 and died of pancreatic cancer a few weeks later; his last hospital room was number 137, and he had long been intrigued by the fine-structure constant, which is approximately 1/137.⁠[6]

The ETH Library’s short portrait states that he died in hospital in Zurich a few days after an attack of pain during a lecture, and the Universität Hamburg’s article that he died unexpectedly of pancreatic cancer; Enz’s article speaks of a short struggle with cancer, and the Dictionary of Scientific Biography of his falling violently and seriously ill in December 1958. The National High Magnetic Field Laboratory’s profile adds that he pointed out the number of his hospital room to his visitors.⁠[10][12][5][8][6]

The Dictionary of Scientific Biography gives the date of death as December 14. At the funeral Victor Weisskopf called him the conscience of theoretical physics.⁠[8][8]

His sister, Hertha Ernestina Pauli, was born in 1906 and died in 1973.⁠[3]

The ETH Library’s exhibition states that she went on to make a name for herself in the United States as an author.⁠[7]

His mother died by suicide in 1927, and his father remarried in 1928.⁠[1][4]

MacTutor’s biography and the Universität Hamburg’s article state that he had been very close to his mother; MacTutor’s biography adds that his father’s remarriage made him still more unhappy and that he referred to his father’s new wife as the evil stepmother. The National High Magnetic Field Laboratory’s profile places his mother’s death around the time of his first marriage and divorce.⁠[4][12][6]

He had no children from either marriage. His second wife, Franca Pauli, was born in 1901 and died in July 1987.⁠[6][3][16]

The National High Magnetic Field Laboratory’s profile states that the second marriage lasted until his death; the American Institute of Physics’ record lists his wives as “Deppner, Kathe,” noted as his first wife, and “Bertram, Franciska,” noted as his second wife, married in 1934.⁠[6][9]

Britannica’s article notes that his critical insight earned him the name “conscience of physics”; the Wolfgang Pauli Centre’s page attributes the description to Isidor Rabi.⁠[1][22]

The Wolfgang Pauli Centre’s page gives Rabi’s words as “Kind, forthright, and of uncompromising principles he was the conscience of physics.” The ETH Library’s exhibition states that in theoretical controversies he was regarded as the supreme authority and that colleagues both valued and feared his impartial criticism; the ETHistory page ties the nickname to his unsparing judgments and his adherence to the principles of an independent and pure science. Enz’s article notes that it was the older physicists who called him so.⁠[22][38][34][15][5]

Markus Fierz, in the Dictionary of Scientific Biography, describes him as sharp and critical in discussion and as a Socratic teacher who helped others to develop their ideas.⁠[8]

Fierz adds that in discussions Pauli was in no way willing, and perhaps completely unable, to accept unclear formulations, that he was hard to convince and reacted sharply, which forced his partner in discussion to self-criticism, and that his attacks, although occasionally malicious, were not intended to be mean and had a humorous, ironic side. Enz’s article notes that his sharp wit was already well known by the early 1920s, and the ETHistory page that his witty everyday remarks are proverbial and were collected as Pauli anecdotes.⁠[8][5][15]

The “Pauli effect” was the belief that his mere presence in a laboratory caused mishaps. Otto Stern believed in it and would not let him enter his laboratory; Fierz adds that Pauli himself believed in it too.⁠[8][5]

The ETHistory page calls the effect a joke that was formulated as a second Pauli exclusion principle, namely that Pauli and a working apparatus could not be in the same room, and states that he treated it with humor while seeing in it more than an anecdote. Enz’s article states that he believed in the effect and was amused by it; the Dictionary of Scientific Biography counts Stern, who was friendly with him, among the critical scholars who believed in it, and the Universität Hamburg’s article states that colleagues feared the effect.⁠[15][5][8][12]

Charles Enz relates that in 1922 Paul Ehrenfest remarked that he liked Pauli’s encyclopedia article better than Pauli himself, to which Pauli replied that with him it was just the opposite.⁠[5]

Fierz also records his remark to a colleague that in his youth he had believed himself a revolutionary and now saw that he was a classicist.⁠[8]

MacTutor’s biography closes with a quotation from the author of its reference 3, which it lists as the biography in Encyclopaedia Britannica: he had a genius for fastening on some one point that could be made simple and, so presented, was seen at once to be important, and the simplicity that was in his nature as well as in his thinking also made him well loved. Britannica’s article credits him with major contributions to quantum mechanics, quantum field theory and solid-state physics and with masterful syntheses of several areas of physical theory that are considered classics of scientific literature, and states that his personal dealings with other scientists left a deep influence, documented in testimonies and in a large correspondence; the Wolfgang Pauli Centre’s page states that he was admired for his critical intellect and his mathematical rigor.⁠[4][1][22]

Enz’s article notes that an inquiry by Physics World into the ten most important physicists of all time did not include him, and the Universität Hamburg’s article that, although he is counted among the most important physicists of the 20th century, he is now almost unknown outside science. The biographical note attached to the Institute for Advanced Study’s member record calls him outstanding among the brilliant school of physicists of the mid-twentieth century.⁠[5][12][35]

His essays, Aufsätze und Vorträge über Physik und Erkenntnistheorie, were published by Vieweg in 1961; his Collected Scientific Papers, edited by Ralph Kronig and Victor Weisskopf, appeared in 1964; and the English selection Writings on Physics and Philosophy, edited by Charles Enz and Karl von Meyenn, was published by Springer.⁠[11][16]

CERN Courier dates Writings on Physics and Philosophy to 1992, the Neue Deutsche Biographie to 1994. The list of works in the Neue Deutsche Biographie also gives a second edition of the essays (1984, edited by Karl von Meyenn), a collection in which his history of the neutrino, “Zur älteren und neueren Geschichte des Neutrinos,” was first printed in 1961, and the volume Das Gewissen der Physik (1988), edited by Enz and von Meyenn. The memorial volume of 1960 was edited by Markus Fierz and Victor Weisskopf.⁠[16][11]

He exchanged several thousand letters with Einstein, Bohr, Heisenberg and others. Under a contract between CERN and Springer-Verlag his scientific correspondence has been published: volume 1 (1979), edited by Hermann, von Meyenn and Weisskopf, contains 242 letters from 1919–1929; volume 2 (1985) covers 1930–1939; volume 3 covers 1940–1949; and volume 4, covering 1950–1958 and planned to include more than two thousand letters, was issued as four separate books, the first of which (1950–1952) appeared in 1996.⁠[16]

CERN Courier gives further details of the edition: the letters are printed in their original languages, at first mostly German and later increasingly English; volume 2 contains 364 letters and 15 earlier ones; volume 3, also edited by von Meyenn, 486 letters and 67 earlier ones; the first book of volume 4 about 450 letters, roughly 100 of them on psychology, and the second (1953–1954, about 1,100 pages) about 450 letters, 50 of them on psychological matters, the third (1955–1956) being announced for the end of 2000. The Neue Deutsche Biographie dates volume 3 to 1993 and the second book of volume 4 to 1999, whereas CERN Courier dates that book to 1998. For this editorial work von Meyenn received the Marc-Auguste Pictet medal in 2000.⁠[16][11]

His correspondence with Jung from 1932 to 1958, edited by C. A. Meier, was published by Springer in 1992 and later translated into English, French and Spanish.⁠[16][11]

CERN Courier adds that Meier compiled the edition with the help of Enz and Fierz and names the publishers of the translations: Routledge in London and Princeton University Press for the English, Albin Michel in Paris for the French, and for the Spanish a Madrid publisher printed as “Alienza Editorial.”⁠[16]

A complete bibliography of his writings is printed in the memorial volume Theoretical Physics in the Twentieth Century, published in New York in 1960.⁠[8]

The American Institute of Physics’ record names further books: “Österreichische Mathematik und Physik,” entered as co-written with Wolfgang Grobner and Richard von Mises; “Vorlesung über Wellenmechanik,” on which Fritz Herlach and Heinz Knoepfel collaborated; and, with Gunnar Källén, “Prinzipien der Quantentheorie” and a work on the mathematical structure of T. D. Lee’s model of a renormalizable field theory.⁠[9]

Literature on him listed in the Neue Deutsche Biographie includes the memoir by R. E. Peierls in volume 5 (1960) of the Biographical Memoirs of Fellows of the Royal Society, recollections by C. F. von Weizsäcker (1959), P. Jordan (1973) and V. F. Weisskopf (Physics Today, 1985), G. Gamow’s “The Exclusion Principle” (Scientific American, 1959), S. A. Goudsmit’s article on Pauli and nuclear spin (Physics Today, 1961), studies by Karl von Meyenn, D. Serwer, J. L. Heilbron and C. Jensen, and E. P. Fischer’s An den Grenzen des Denkens (2000). The ETH Library names the volume Wolfgang Pauli und sein Wirken an der ETH Zürich (Zurich, 1997), edited by Charles P. Enz, Beat Glaus and Gerhard Oberkofler from the files of ETH Zurich; CERN Courier announced in 2000 that Enz’s biography of Pauli was expected to be completed in 2002.⁠[11][10][16]

In October 1931 he received the Lorentz Medal of the Netherlands academy of sciences in Amsterdam; the American Institute of Physics’ record gives the year as 1930.⁠[4][11][9]

He also received the Franklin Medal of the Franklin Institute (1952) and the Carlo Matteucci Medal of the Accademia Nazionale dei XL in Italy (1956).⁠[11]

He was a member of the Société Philomatique de Paris (1938), the American Academy of Arts and Sciences (1950), the Heidelberg academy of sciences (1950), the Bavarian Academy of Sciences (1951), the Royal Danish Academy of Sciences (1951), the Royal Society (1953) and the Royal Swedish Academy of Sciences (1955).⁠[11]

MacTutor’s biography adds that he was a member of the Swiss Physical Society, the American Physical Society and the American Association for the Advancement of Science.⁠[4]

MacTutor’s biography also records that he was a speaker at the International Congress of Mathematicians of 1932 and that a crater on the Moon is named after him.⁠[4]

After his death Franca Pauli, assisted by Charles Enz, began to put his papers in order; Victor Weisskopf and Ralph Kronig helped to send out a circular letter asking for correspondence, and Niels Bohr and J. Robert Oppenheimer supported the effort.⁠[20]

On August 25, 1960, Franca Pauli made a first deed of gift of part of the estate to CERN, followed by a second deed on November 5, 1971; in 1965 CERN created the Pauli Committee to look after the collection, and after her death CERN inherited the author’s rights in Pauli’s scientific work.⁠[20]

CERN Courier gives the later history of the committee: after Weisskopf’s term as Director-General of CERN (1961–1965) a committee chaired by his successor Bernard Gregory took charge of the archive, and responsibility for the collection passed to CERN’s Scientific Information Service; Weisskopf remained a member; when Léon Van Hove’s term as Director-General ended in 1981, Herwig Schopper mandated him to retain the chairmanship of the committee; Maurice Jacob succeeded him as chairman when Van Hove retired from CERN in 1989, and Gabriele Veneziano is named as Jacob’s successor. The committee was reorganized in 1985: Charles Enz of the University of Geneva joined, shortly followed by H. Primas of ETH Zurich and by Jacob as CERN representative; in 1997 Enz and Primas retired from their university posts and left the committee and were replaced by W. Amrein of Geneva and K. Osterwalder of ETH Zurich; K. von Meyenn had already joined by then, and R. Mumenthaler joined later to strengthen the links with the ETH Library. The archivists named are Roswitha Rahmy and, after her, Anita Hollier. The CERN Archives’ page names Wolfgang Lerche as the committee’s current chairman. The committee meets formally once a year, until 1997 at the time of Weisskopf’s customary summer visit to the Geneva area.⁠[16][39]

The Pauli Archive at CERN holds his scientific books, reprints, correspondence, manuscripts and photographs, together with his Nobel Prize and other scientific awards; CERN has a memorial room, the Salle Pauli, and the collection also includes his baptismal cup.⁠[39][20]

The fonds description calls the Salle Pauli collection Pauli’s library, with his books on scientific and other subjects and his reprints; CERN Courier calls the room the Pauli Room, where many memorabilia and books are kept. The fonds description states that copyright is retained by CERN and that nothing may be reproduced without permission; the archive’s page adds that permission to publish or quote from Pauli’s work must be obtained from the Pauli Committee through the CERN Archivist. Among the documents shown with the CERN Archives’ biography are photographs of him at 20 months with his mother (December 1901) and at the age of four (July 1904), his high school diploma of July 1918 and his Nobel Prize certificate of 1945.⁠[20][16][39][13]

The ETH Library holds a further collection known as the “Pauliana,” which includes his correspondence with Markus Fierz, Jung and Marie-Louise von Franz.⁠[16]

The ETH Library’s short portrait states that the ETH Zurich University Archives hold the school’s historical administrative records with many documents on Pauli, that papers of other scholars kept there contain letters of his, among them a letter of March 28, 1955, to Bartel Leendert van der Waerden (shelf mark Hs 652:6888), and that his widow gave his personal papers to the CERN Archive. CERN Courier notes that the editors were still tracing scattered letters, many of which were found in J. Robert Oppenheimer’s files at Princeton and in Jauch’s files in Geneva.⁠[10][16]

For the centenary of his birth in 2000 the ETH Library mounted an exhibition in Zurich in April and May, which was then shown at CERN from August 17 to September 26.⁠[16]

The ETH Library dates its exhibition to April 6–May 6, 2000, and keeps an online version, “Wolfgang Pauli and modern physics.” CERN Courier announced a ceremony in the CERN Council Chamber for September 11, 2000, at 4:30 p.m., with Maurice Jacob, chairman of the Pauli Committee, Konrad Osterwalder, Rektor of ETH Zurich, Luciano Maiani, Director-General of CERN, and Charles Enz of the University of Geneva as speakers.⁠[38][16]

In November 2005 the Faculty of Mathematics, Informatics and Natural Sciences of the University of Hamburg named a lecture hall the Wolfgang Pauli-Hörsaal, and eight years later the faculty and DESY named the newly founded center for theoretical physics the Wolfgang Pauli Centre.⁠[12]

The lecture hall was inaugurated with a festive colloquium; Wilfried Buchmüller, then spokesperson of the Wolfgang Pauli Centre, explained the choice of name by saying that Pauli stood for brilliant research in several fields of theoretical physics, among them quantum theory, particle physics, relativity and cosmology.⁠[12]

CERN Archives (Pauli Archive): Official website: https://archives.cern/pauli_archive/ (opens in a new window).⁠[39]

University of Göttingen: Official website: https://uni-goettingen.de/ (opens in a new window).⁠[40]

University of Hamburg: Official website: https://www.uni-hamburg.de/ (opens in a new window).⁠[41]

ETH Zurich: Official website: https://ethz.ch/en.html (opens in a new window).⁠[42]

Institute for Advanced Study: Official website: https://www.ias.edu/ (opens in a new window).⁠[26]