My research is in probability, and concentrates mainly on systems with an underlying branching structure.

This includes traditional mathematical models such as branching Brownian motion and Galton-Watson trees. We imagine a system of organisms, each of which moves around in space, breeds and eventually dies. Does the population survive forever, or eventually die out? How quickly does it colonise space?

It turns out that these mathematical questions have some surprising applications, and I am also interested in ways of using branching models to study other objects: computer algorithms, mutation rates in evolutionary biology, and mixing times for Markov chains, to name a few examples.