2008 Dirac medal

Professor Bryan Webber

University of Cambridge

For his pioneering work in understanding and applying quantum chromodynamics (QCD), the theory of the strong interaction which is one of the three fundamental forces of Nature.

The Dirac medal of the Institute of Physics for outstanding contributions to theoretical, mathematical and computational physics has been awarded to Professor Bryan R Webber, Professor of Theoretical Physics at the University of Cambridge, for his pioneering work in understanding and applying quantum chromodynamics (QCD), the theory of the strong interaction which is one of the three fundamental forces of Nature.

The strong force is felt by quarks, the constituents of protons and neutrons, and is carried by gluons which themselves interact via the strong force. To verify that the theory is correct requires being able to make accurate predictions of its consequences in particle physics experiments. Since the interactions are complex, this represents a formidable challenge.

Professor Webber is recognised worldwide as having a profound understanding of QCD - from which he has derived key practical numerical tools for extracting quantitative information from high-precision experimental data. Over the past 20 years, these tools have been used in high-energy experiments around the world, for example, in the Large Electron-Positron Collider at CERN. 

Webber proposed a number of successful models that show what happens during high-energy particle collisions, for example, the break-up of quarks into jets of other particles. He developed powerful algorithmic approaches that not only allow much more accurate interpretation of particle events but also provide theoretical insights into the complexities of QCD. His work led to the theoretical consolidation of QCD, as recognised by the ensuing award of the Nobel Prize to the originators of the theory.

Recently, Webber performed ground-breaking work on the phenomenology associated with the kind of physics that will be explored in the very high energy proton-proton collisions shortly to begin at the Large Hadron Collider at CERN. Professor Webber’s contributions to our understanding of the fundamental properties of matter have been invaluable, as revealed by the large number of citations of his published research.