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The nature and evolution of the highly ionized near-zones in the absorption spectra of z~6 quasars (2006)
Journal Article
S. Bolton, J., & G. Haehnelt, M. (2007). The nature and evolution of the highly ionized near-zones in the absorption spectra of z~6 quasars. Monthly Notices of the Royal Astronomical Society, 374(2), 493–514. https://doi.org/10.1111/j.1365-2966.2006.11176.x

We use state-of-the-art hydrodynamical simulations combined with a 1D radiative transfer code to assess the extent to which the highly ionized regions observed close to z~6 quasars, which we refer to as near-zones, can constrain the ionization state... Read More about The nature and evolution of the highly ionized near-zones in the absorption spectra of z~6 quasars.

Scaling in a SU(2)/Z_3 model of cosmic superstring networks (2006)
Journal Article
Hindmarsh, M., & Saffin, P. (2006). Scaling in a SU(2)/Z_3 model of cosmic superstring networks. Journal of High Energy Physics, 2006(8), https://doi.org/10.1088/1126-6708/2006/08/066

Motivated by recent developments in superstring theory in the cosmological context, we examine a field theory which contains string networks with 3-way junctions. We perform numerical simulations of this model, identify the length scales of the netwo... Read More about Scaling in a SU(2)/Z_3 model of cosmic superstring networks.

Scaling solutions and geodesics in moduli space (2006)
Journal Article
Karthauser, J., & Saffin, P. M. (2006). Scaling solutions and geodesics in moduli space. Classical and Quantum Gravity, 23(14), https://doi.org/10.1088/0264-9381/23/14/004

In this paper we consider cosmological scaling solutions in general relativity coupled to scalar fields with a non-trivial moduli space metric. We discover that the scaling property of the cosmology is synonymous with the scalar fields tracing out a... Read More about Scaling solutions and geodesics in moduli space.

M-theory on seven-dimensional manifolds with SU(3) structure (2006)
Journal Article
Micu, A., Palto, E., & Saffin, P. (2006). M-theory on seven-dimensional manifolds with SU(3) structure. Journal of High Energy Physics, 2006(5), https://doi.org/10.1088/1126-6708/2006/05/048

In this paper we study M-theory compactifications on seven-dimensional manifolds with SU(3) structure. As such manifolds naturally pick out a specific direction, the resulting effective theory can be cast into a form which is similar to type IIA comp... Read More about M-theory on seven-dimensional manifolds with SU(3) structure.

The Dynamics of coset dimensional reduction (2006)
Journal Article
Karthauser, J. L., & Saffin, P. M. (2006). The Dynamics of coset dimensional reduction. Physical Review D, 73(8), https://doi.org/10.1103/PhysRevD.73.084027

The evolution of multiple scalar fields in cosmology has been much studied, particularly when the potential is formed from a series of exponentials. For a certain subclass of such systems it is possible to get `assisted` behaviour, where the presence... Read More about The Dynamics of coset dimensional reduction.

Spatial fluctuations in the spectral shape of the UV background at 2 (2006)
Journal Article
S. Bolton, J., G. Haehnelt, M., Viel, M., & F. Carswell, R. (2006). Spatial fluctuations in the spectral shape of the UV background at 2. Monthly Notices of the Royal Astronomical Society, 366(4), 1378-1390. https://doi.org/10.1111/j.1365-2966.2006.09927.x

The low density hydrogen and helium in the IGM probed by QSO absorption lines is sensitive to the amplitude and spectral shape of the metagalactic UV background. We use realistic HI and HeII Ly-alpha forest spectra, constructed from state-of-the-art... Read More about Spatial fluctuations in the spectral shape of the UV background at 2.