Thursday, April 23, 2009

Wolfgang Pauli


Wolfgang Ernst Pauli was an Austrian theoretical physicist noted for his work on spin theory, and for the discovery of the exclusion principle underpinning the structure of matter and the whole of chemistry.

Pauli was born in Vienna to Wolfgang Joseph Pauli (né Wolf Pascheles) and Berta Camilla Schütz. His middle name was given in honor of his godfather, the physicist Ernst Mach. His paternal grandparents were from prominent Jewish families of Prague, but his father converted from Judaism to Roman Catholicism shortly before his marriage in 1899. Bertha Schütz was raised in her mother's Roman Catholic religion, but her father was the Jewish writer Friedrich Schütz. Although Pauli was raised as a Roman Catholic, eventually he and his parents left the Church.

Pauli attended the Döblinger-Gymnasium in Vienna, graduating with distinction in 1918. Only two months after graduation, the young prodigy published his first paper, on Albert Einstein's theory of general relativity. He attended the Ludwig-Maximilians University in Munich, working under Arnold Sommerfeld, where he received his PhD in July 1921 for his thesis on the quantum theory of ionised molecular hydrogen.

Sommerfeld asked Pauli to review the theory of relativity for the Encyklopaedie der mathematischen Wissenschaften (Encyclopedia of Mathematical Sciences). Two months after receiving his doctorate, Pauli completed the article, which came to 237 pages. It was praised by Einstein; published as a monograph, it remains a standard reference on the subject to this day.

Pauli spent a year at the University of Göttingen as the assistant to Max Born, and the following year at the Institute for Theoretical Physics in Copenhagen, which later became the Niels Bohr Institute in 1965. From 1923 to 1928, he was a lecturer at the University of Hamburg. During this period, Pauli was instrumental in the development of the modern theory of quantum mechanics. In particular, he formulated the exclusion principle and the theory of nonrelativistic spin.

At the beginning of 1931, shortly after his divorce and immediately following his postulation of the neutrino, Pauli had a severe breakdown. He consulted the psychiatrist and psychotherapist Carl Jung who, like Pauli, lived near Zürich. Jung immediately began interpreting Pauli's deeply archetypal dreams, and Pauli became one of the depth psychologist’s best students. Soon, he began to criticize the epistemology of Jung’s theory scientifically, and this contributed to a certain clarification of the latter’s thoughts, especially about the concept of synchronicity. A great deal of these discussions is documented in the Pauli/Jung letters, today published as Atom and Archetype. Jung's elaborate analysis of more than 400 of Pauli's dreams is documented in Psychology and Alchemy.

In 1928, he was appointed Professor of Theoretical Physics at ETH Zürich in Switzerland where he made significant scientific progress. He held visiting professorships at the University of Michigan in 1931, and the Institute for Advanced Study at Princeton in 1935. He was awarded the Lorentz Medal in 1931.

The German annexation of Austria in 1938 made him a German national, which became a difficulty with the outbreak of World War II in 1939. Pauli moved to the United States in 1940, where he was Professor of Theoretical Physics at Princeton. After the war, in 1946, he became a naturalized citizen of the United States, before returning to Zürich, where he mostly remained for the rest of his life.

In 1945, he received the Nobel Prize in Physics for his "decisive contribution through his discovery in 1925 of a new law of Nature, the exclusion principle or Pauli principle." He was nominated for the prize by Albert Einstein.

In 1958, Pauli was awarded the Max Planck medal. In that same year, he fell ill with pancreatic cancer. When his last assistant, Charles Enz, visited him at the Rotkreuz hospital in Zürich, Pauli asked him: “Did you see the room number?” It was number 137. Throughout his life, Pauli had been preoccupied with the question of why the fine structure constant, a dimensionless fundamental