Born into a semi-aristocratic family in Basel in 1905, Stueckelberg's father was a lawyer, and his paternal grandfather a distinguished Swiss artist. A highly giftedschool student, Stueckelberg initially began a physics degree at the University of Basel in 1923.
Career
While still a student, Stueckelberg was invited by the distinguished quantum theorist Arnold Sommerfeld, to attend his lectures at the University of Munich. He went on to gain a Ph.D. on cathode physics in 1927. Later that year he went to Princeton University, becoming an assistant professor in 1930. He was elected a Fellow of the American Physical Society in 1931. He returned to Switzerland in 1932, working first at the University of Basel before switching the following year to the University of Zurich. In 1934 he moved again to the University of Geneva, which together with the University of Lausanne became his principal bases for the rest of his career. Stueckelberg's sojourn in Zurich led to contact with leading quantum theorists Wolfgang Pauli and Gregor Wentzel, which in turn led him to focus on the emerging theory ofelementary particles. In 1934 he devised a fully Lorentz-covariantperturbation theory for quantum fields. The approach proposed by Stueckelberg was very powerful, but was not adopted by others at the time, and has now been all but forgotten. However, besides being explicitly covariant, Stueckelberg's methods avoid vacuum bubbles. Stueckelberg developed the vector boson exchange model as the theoretical explanation of the strong nuclear force in 1935. Discussions with Pauli led Stueckelberg to drop the idea, however. It was rediscovered by Hideki Yukawa, who won a Nobel Prize for his work in 1949 — the first of several Nobel Prizes awarded for work which Stueckelberg contributed to, without recognition. In 1938 Stueckelberg recognized that massive electrodynamics contains a hidden scalar, and formulated an affine version of what would become known as the Abelian Higgs mechanism. He also proposed the law of conservation of baryon number. The evolution parameter theory he presented in 1941 and 1942 is the basis for recent work in relativistic dynamics. In 1941 he proposed the interpretation of the positron as a positive energy electron traveling backward in time. In 1943 he came up with a renormalization program to attack the problems of infinities in quantum electrodynamics, but his paper was rejected by the Physical Review. In 1952 he proved the principle of semi-detailed balance for kinetics without microscopic reversibility. In 1953 he and the mathematician André Petermann discovered the renormalization group. In 1976 he was awarded the Max Planck medal. His PhD students included Marcel Guénin.
