Wolfgang Pauli

Wolfgang Ernst Pauli was born in Vienna on April 25, 1900, to Wolfgang Joseph Pauli, a chemist, and Berta Camilla Schütz. His father, originally from Prague, had converted from Judaism to Catholicism; his godfather was the physicist and philosopher Ernst Mach. Pauli showed early mathematical talent and, after graduating from the Döblinger Gymnasium in 1918, went straight to the University of Munich to study under Arnold Sommerfeld. Sommerfeld asked him to write an encyclopedia article on relativity, which Pauli completed at age 19; it was praised by Einstein and remains a classic review.¹ Pauli earned his doctorate in 1921 with a thesis on the hydrogen molecule ion, and then spent a year at the University of Göttingen as an assistant to Max Born.

In 1925, Pauli published his exclusion principle, which states that no two electrons in an atom can occupy the same quantum state simultaneously. This principle explained the periodic table and the shell structure of atoms, earning him the 1945 Nobel Prize in Physics.² He also made seminal contributions to quantum field theory, including the Pauli–Villars regularization and the spin-statistics theorem, which he formulated with Markus Fierz. In 1930, to explain the continuous energy spectrum of beta decay, Pauli proposed the existence of a new neutral, weakly interacting particle; Enrico Fermi later named it the neutrino.³ Pauli also developed a nonrelativistic two-component equation for spin-½ particles, a precursor to the Dirac equation.

After teaching at the Federal Institute of Technology in Zurich (ETH) from 1928 onward, Pauli emigrated to the United States during World War II, becoming a professor at the Institute for Advanced Study in Princeton. He returned to Zurich in 1946. Pauli had a deep interest in philosophy and psychology, engaging in a correspondence with the psychoanalyst Carl Jung on the connection between physics and the archetypes of the unconscious.⁴ He was known for his acerbic wit and exacting standards, often ruthlessly critiquing both colleagues and students.⁵ Pauli died in Zurich on December 15, 1958.

Beyond his celebrated work, Pauli made several lesser-known contributions. He derived the first correct proof of the CPT theorem, though he published it only in 1955 in a volume honoring Niels Bohr.³ He also proposed a model for the nuclear force before the discovery of the meson, and he co-invented the concept of isospin. Pauli's famous "Pauli effect" — the mysterious tendency for experimental equipment to fail in his presence — became a running joke among physicists, though he took it seriously enough to consult Jung.⁴ His correspondence, now preserved in the Pauli collection at CERN, reveals his role in the early debates on quantum electrodynamics and his sharp insights into the foundations of the theory.

Exclusion principle

Quantum mechanical principle that no two identical fermions can occupy the same quantum state.

Beta decay

A type of radioactive decay in which a beta particle (electron or positron) is emitted.

Spin-statistics theorem

The theorem that connects the intrinsic spin of a particle with the statistics it obeys (Fermi–Dirac or Bose–Einstein).