Mapping dark matter in the universe

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We now have strong evidence from many different types of astronomical observations that most of the matter in our universe is dark matter, an exotic substance that does not produce or interact with light almost at all. This dark matter, which manifests itself only through its gravitational effects, provides the scaffolding within which luminous structures such as galaxies can form, and thus it plays a vital role in cosmology. Furthermore, although the particle nature of dark matter is still unknown, the candidate particle or particles are constrained to lie outside the current 'standard model' of particle physics. Thus, the identification of dark matter is a top priority both for astrophysicists and for particle physicists. Knowing exactly where to look for dark matter is an important first step. The main goal of my research programme is to understand and to map out the distribution of dark matter in the universe, particularly on small scales where it is the most uncertain. Using novel computational techniques, I will model the dark matter distribution within our Galaxy and within our Solar System at unprecedented resolution. These models will be applied to the analysis of ongoing experiments in dark matter detection. I will also use gravitational lensing, the deflection of light as it passes through a gravitational field, to map small-scale dark matter structures in galaxy clusters, and to study how they evolve as clusters grow. Finally, I will search around the Milky Way and other nearby galaxies for very faint 'dwarf' galaxies that trace dark matter on the smallest scales.