Veltman, Martinus (1931– )

Dutch physicist who with Dutch physicist Gerardus 't Hooft was awarded the Nobel Prize for Physics in 1999 for his work in the determination of the quantum structure of electroweak interactions in physics.

Physicists describe the interactions between particles using gauge theories. In the 1960s researchers developed a theory that united the theories concerning electromagnetism and the weak interaction associated with radioactive decay. The combined theory was known as the non-abelian gauge theory of electroweak interaction. The theory predicted the existence of new types of subatomic particles, which were discovered in 1983. However, the theory was found to be unsatisfactory in its predictions of the behaviours of these particles and gave unreasonable results. To correct the theory required renormalization, a technique developed in the 1940s by US physicist Richard P Feynman (1965 Nobel prizewinner) and his associates.

Veltman had developed the computer program Schoonschip to help perform quantum calculations in the late 1960s. He had been working on the problem of renormalizing the non-abelian gauge theory and had presented the problem to his student Gerardus 't Hooft as a research project. Veltman used his program to confirm his student's results and expand upon them to complete the renormalization of the theory. The result was a working version of the non-abelian gauge theory that allowed precise calculations involving the electroweak interaction. The renormalized theory also predicted a new particle that was called the top quark, which was found experimentally in 1995. This work has helped advance the field of particle physics.

Veltman was born in the Netherlands. He received his PhD degree in theoretical physics from the University of Utrecht in1963, where he became a professor of physics in 1966. He retained this position until 1981, when he became the John D and Catherine T MacArthur professor of physics at the University of Michigan, Ann Arbor, USA. He became a member of the Dutch Academy of Science in 1981 and was named a fellow of the American Physical Society in 1984.