Dirac Medallists 1987

Bruno Zumino, University of California, Berkeley, USA

who has been for the last twenty years one of the leading experts in field theory. Together with Prof. Julius Wess, he has made fundamental contributions to the study of chiral anomalies in gauge theories with fermions. Also in collaboration with Prof. Wess, he proposed the first renormalizable Lagrangian field theories to realize supersymmetry in 4-dimensional space-time. With Prof. Stanley Deser he constructed one of the first supergravity theories in four dimensions. In addition to this important early work, he has been a leader in the application of modern geometrical ideas in field theory. In particular he has illuminated the role of Kähler geometry in extended supergravities and, more generally, the value of differential geometric methods in the study of anomalies.

Bryce DeWitt (1923-2004)
University of Texas, Austin, USA

for his fundamental contributions to the study of classical and quantum gravity and non-Abelian gauge theory. His pioneering work with quantum, effective action underlies much of the modern formalism. Particularly important are the background field method which he invented, and the methodology of ghost loops in gauge theory, which he did much to develop. His name is associated with the Wheeler-DeWitt equation, which provides the basis for most work on quantum cosmology, and with the Schwinger-DeWitt expansion, which is widely used in studying field theories in curved space-time and in string theory computations.