Office: Hoyle H29
Office Tel: (01223) 766668
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My research has so far been directed towards using gravitational-wave (GW) detections to probe the background cosmology of the Universe, and aspects of the GW-emitting source distribution. Particularly, in the advanced detector era (~2015+), the inspiral and merging of NS-NS binary systems are expected to be a ubiquitous source of gravitational waves. It is in these kinds of systems that general relativity plays an important role, with the emission of gravitational waves driving the neutron stars towards each other, eventually merging together.
The gravitational waves from such systems directly encode the luminosity distance to the source, as well as the redshifted system mass. We can only disentangle the redshift from this redshifted-mass if we already have a good idea what the system mass might be. This then permits these systems to be used as 'standard sirens' to calibrate the distance-redshift relation, extracting the Hubble constant and possibly other cosmological parameters. Not only that, but we can probe the distribution of neutron star masses in these NS-NS systems. Thus, we can perform cosmology and astrophysics with GW's without any electromagnetic measurements.
I am also interested in the stochastic background of gravitational waves. This may have an astrophysical and a cosmological origin. The astrophysical source may result from overlapping GW's from many galactic or cosmological compact binary systems, essentially producing a random field. The cosmological source may result from early Universe processes, such as phase transitions, or from decaying cosmic strings.
S. R. Taylor, and J. R. Gair, "Cosmology with the lights off: Standard sirens in the Einstein Telescope era", Phys. Rev. D 86, 023502 (2012), 1204.6739, DOI:10.1103/PhysRevD.86.023502, arXiv:1204.6739