I currently hold the post of Senior Lecturer in Astronomy, in the Department of Physics and Astronomy of the University of Glasgow. I am a member of the Astronomy and Astrophysics research group, led by Prof. John Brown (Astronomer Royal for Scotland). I head a small research team working in cosmology, which is the branch of astrophysics concerned with the large-scale properties of the Universe as a whole: its origin, evolution and eventual fate.
I took up my present appointment at Glasgow University
in October 1998, having previously held research positions at Glasgow (1996-1998)
and at Sussex University (1991-1996),
following the completion of my PhD, also at Glasgow.
My main research interests are:-
Precise determination of the size and age of the Universe, from (among other methods) Hubble Space Telescope observations of stars in distant galaxies. These observations confirm that the Universe is expanding - in agreement with the predictions of the standard 'Big Bang' theory. Moreover, by accurately measuring the rate of expansion we can determine whether the Universe will continue to expand forever, or will eventually re-collapse in a 'Big Crunch'. Most evidence currently points towards the former fate - indeed the Universe appears to be accelerating, which means that on very large scales the expansion is being driven by the vacuum energy of space itself! This startling conclusion poses a number of puzzles for astronomers and particle physicists, including questions about the 'fine tuning' of the Universe.Public Outreach Activities
Testing theories for the formation and evolution of galaxies. The pattern of galaxies and clusters which we observe today was assembled by gravity, causing tiny ripples in the density of the very early Universe to grow over billions of years. We can measure the pattern, or spectrum, of these primordial density variations very precisely, and this determines the ingredients which make up the 'recipe' for galaxy formation. Although the list of ingredients is becoming well understood, the details of the recipe (e.g the amount of ingredients and cooking time) remains an unsolved problem for cosmologists, and one of the biggest puzzles is understanding where and how much dark matter there is in the Universe - in addition to the luminous matter we see as stars and galaxies. We can obtain some valuable clues about the dark matter, however, by careful analysis of the clustering and motion of galaxies.
Exploring new applications of gravitational lensing. Einstein's general relativity correctly predicted that light from a distant star would be deflected by a tiny amount as it passed close to intervening matter. This phenomenon - known as gravitational lensing - has recently become a powerful technique for detecting dark matter in the halo of our galaxy. Our work explores the use of lensing to probe the atmospheres of stars and 'image' their surfaces - revealing e.g. star 'spots' - with further application to detecting extra-solar planets.
I am very active in promoting a greater public awareness and understanding of astronomy, and science in general, throughout the wider community. My public outreach activities are:-