Gerard 't Hooft
active c. 1946, Den Helder, Netherlands
Dutch theoretical physicist who proved spontaneously broken gauge theories are renormalizable — the foundation of the Standard Model; also known for the 't Hooft–Polyakov monopole and the holographic principle.
't Hooft studied at Utrecht University and earned his PhD in 1972 under Martinus Veltman, with a thesis on the renormalization of Yang–Mills theories. He worked at CERN before returning to Utrecht, where he became professor in 1977.
His proofs turned the Glashow–Weinberg–Salam electroweak model into a quantitatively computable theory, leading to correct predictions of the W and Z masses. He also made influential contributions on gauge monopoles, instantons, the 1/N expansion, and the holographic principle of quantum gravity. He shared the 1999 Nobel Prize in Physics with Veltman.
Nobel-winning work
In the early 1970s the Yang–Mills theory of the weak and electromagnetic interactions was stuck: nobody knew whether it gave finite, predictive results once quantum corrections were included. In 1971–1972 't Hooft proved that non-Abelian gauge theories — both unbroken and spontaneously broken via the Higgs mechanism — are renormalizable.
Combined with the dimensional-regularization technique developed with Veltman, this turned the Standard Model from a conjectural scheme into a precision instrument: low-energy parameters predicted the W and Z masses, confirmed at CERN in 1983. The 1999 Nobel recognized work that 'elucidated the quantum structure of electroweak interactions'.
Workplaces: Utrecht University
Netherlands