I am interested in the theory and phenomenology of the Standard Model of particle physics and focus primarily on the strong interaction that binds quarks and gluons into protons and neutron and eventually into nuclei. The Standard Model of particle physics, and the understanding of the natural world that it encompasses, is a testament to the ingenuity, creativity and tenacity of physicists worldwide. Whilst we still seek to find its weaknesses at the shortest distances, this theory has stood up to almost 50 years of scrutiny in experiment without blemish, culminating in the recent discovery of the Higgs boson at the Large Hadron Collider (LHC).

Within our current understanding the strong interaction is described by the quantum filed theory of Quantum Chromodynamics (QCD), developed in the 1970s by my colleague Frank Wilczek amongst others. A remarkable property of this theory is *asymptotic freedom* whereby the strength of the interactions between quarks and gluons vanishes logarithmically as they get closer to each other. As a consequence, at high energy (short distance) we can make accurate QCD predictions that compare remarkably well with experiment, allowing us to conclude that QCD is the theory of the strong interaction. However at low energies relevant for protons and nuclei, QCD becomes strongly coupled and we must turn to computational methods known as lattice QCD to make rigorous predictions.

I focus on trying to understand the emergence of the complex structures of hadronic and nuclear physics from the underlying simplicity of the Standard Model which presents a grand challenge to our ability to describe and understand nature at its deepest levels.

My current work focuses on four topics

- Heavy quark systems and tests of the Standard Model
- The structure of the proton
- The physics of nuclei and the emergence of complex structures in QCD
- Computational aspects of lattice QCD