Astrophysical fluid dynamics, dynamo theory, plasma kinetic and gyrokinetic theory, magnetised plasma turbulence in astrophysical and space plasmas, magnetic reconnection; solar wind, interstellar medium, galaxy clusters; turbulence and transport in fusion plasmas.
The unifying theme of my group's research is understanding the dynamics of multiscale turbulent plasma systems. Microscopic particle motion and electromagnetic fluctuations combine to give rise to macroscale characteristics of a turbulent plasma that determine how it transports energy and momentum. Hence one can infer effective models for a variety of interesting systems — from the largest plasma objects in the Universe, the galaxy clusters, to our native plasma environment, the solar wind, to magnetically confined plasmas in the prototypical fusion power plants, tokamaks, here on Earth. In the space and astrophysical systems, our research is driven by the imperative of human curiosity: space probes measuring the conditions in the heliosphere, orbiting X-ray observatories and giant radiotelescopes peering at the distant galaxies tell us that plasma energy is distributed in space in a particular way, show us a Universe filled with tangled magnetic fields and turbulent motions — we must understand these if we are to retain our self-respect as an inquisitive and intellectually restless species. But besides being curious, we are also an extremely energy-consuming species and that presents us with a practical challenge of finding a sustainable long-term energy source. Learning how to lock hot fusing plasma in a magnetic cage — the idea which tokamaks attempt to put into practice — is key to developing a functioning fusion power plant. Here a key challenge is to understand and find methods of controlling the way particles, momentum and heat are transported in a turbulent plasma, as it resists being confined. This is the focus of our fusion-related research, which includes analytical theory, large-scale numerical calculations and direct participation in the experimental measurements taking place at the Culham Laboratory, which houses both the UK's national fusion facility, the MAST tokamak, and the European tokamak, JET — currently the biggest in the world and the best experimental platform to prepare for the operation of the international fusion machine, ITER. Thus, to quote a former member of my group, "our objective is to understand the world — and save it."