Faculty of Technology
Professor Rob Crittenden
- Qualifications: BSc, PhD
- Role Title: Professor of Cosmology, Research Degrees Coordinator (Faculty of Technology)
- Address: Dennis Sciama Building, Burnaby Road, Portsmouth (UK) PO1 3FX
- Telephone: +44 (0)23 9284 5625
- Email: firstname.lastname@example.org
- Department: Institute of Cosmology & Gravitation
- Faculty: Faculty of Technology
My professional life is split between lecturing (physics and applied mathematics) and carrying out research in cosmology. Cosmology is the study of the large scale structure and evolution of our Universe, and uses astronomical observations to try to understand what the Universe is made of and how it came to be the way it is today.
Recently it has been discovered that the Universe is not only expanding, but that the rate of expansion is speeding up. This is thought to be caused by a gravitationally repulsive dark energy which accounts for most of the matter in our Universe. One of my research goals is to better understand the nature of this dark energy using surveys of the distribution of galaxies and observations of light left over from the big bang, known as the cosmic microwave background.
These same observations can tell us about the processes which first generated the seeds of structure during the big bang. Our best model at present for the early Universe is called cosmological inflation, and the observations may be able to tell us more about how it might have happened.
My undergraduate teaching is primarily in Portsmouth's new degree in Applied Physics (download a brochure!) I teach a first year unit called Introduction to Mathematical Physics I . Students in the unit can find course materials on the Moodle website and the Mastering Physics website.
I also teach short courses on advanced topics to the postgraduate students at the ICG. Last year I reviewed the physics of the cosmic microwave background. This year I will teach a statistics course which takes a Bayesian approach to problems in astrophysics. Summary notes from my undergraduate unit may also be of interest, as well as their problem set.
Finally, I recently took over the job of Research Degrees Coordinator for the Faculty of Technology, where I try to help ensure that our graduate students have a productive and successful time while here at the University of Portsmouth.
My research spans a broad range of topics in cosmology and large scale structure, focusing primarily on using the cosmic microwave background (CMB) to probe the physics of the Universe, such as inflation, cosmic defects, magnetic fields and dark energy.
In my PhD thesis, working under the supervision of Paul Steinhardt, I examined how the CMB temperature and polarisation could be used to detect primordial gravity waves, which would say much about the epoch of inflation. In later work with Neil Turok, I showed how the CMB temperature and polarisation would be correlated, an effect which subsequently was detected.
In recent years, I have been using the CMB to constrain models of dark energy and modified gravity, in particular using integrated Sachs-Wolfe effect, where CMB anisotropies are created as dark energy causes gravitational potentials to decay. Neil and I first proposed that the ISW effect could be seen via correlations between the CMB and the local density field (Crittenden and Turok, 1996). This effect was not seen in early CMB data, but when WMAP came out, Stephen Boughn and I were the first to measure it (Nature 2004.) The significance of the signal has mounted as more large scale structure measurements have been exploited (Giannantonio et al. 2008).