Research Fellows Directory
Professor Roger Davies
University of Oxford
My research is aimed at advancing our understanding of cosmology and the evolution of galaxies. To achieve this I have developed new measurement techniques and built instruments to measure the distances, masses, ages and composition of distant galaxies. Our current cosmological paradigm has galaxies in dark matter halos assembling over a long period by repeated collisions and coalescences. This means that the stars that constitute a galaxy today probably formed in a completely different environment. One of the most intriguing paradoxes arising from this picture are the giant elliptical galaxies. The stars in these,most massive of galaxies, are generally old and little or no star formation is present. However cosmological simulations suggest that these objects are dynamically young having undergone their final major mergers in the latter half of the age of the Universe. There are a number of measurements that challenge this picture. If stars formed in different galaxies why is there such a close link between the composition of the stars and the depth of the local potential they find themselves in today? How to blue star forming galaxies evolve into the giant, quiescent star piles found in the densest environments? The new measurements I have undertaking are revealing much more specific insights into galaxy assembly.
I find that the general public and school pupils are fascinated by this general topic and I have well developed talks that I have used to capture their interest. This year I developed a new topic `What has astronomy ever done for us?’ outlining how the technological developments associated with observational astrophysics have permeated into medical imaging and security as well as more traditional applications such as navigation and `space weather’.