Variations of the Fine Structure Constant in Space and Time
Abstract
This thesis describes a detailed investigation of the effects of matter inhomogeneities on the cosmological evolution of the fine structure constant using the BekensteinSandvikBarrowMagueijo (BSBM) theory. We briefly review the observational and theoretical motivations to this work, together with the standard cosmological model. We start by analysing the phase space of the system of equations that describes a timevarying fine structure constant, in a homogeneous and isotropic background universe. We classify all the possible behaviours of the fine structure constant in everexpanding universes and find exact solutions for it. Using a gaugeinvariant formalism, we derive and solve the linearly perturbed Einstein cosmological equations for the BSBM theory. We calculate the time evolution of inhomogeneous perturbations of the fine structure constant on small and large scales with respect to the Hubble radius. We also investigate, in the nonlinear regime of the large scale structure formation, the spacetime evolution of the fine structure constant, inside evolving spherical overdensities. The dependence on the darkenergy equation of state is also analysed. Finally, we analyse the effects of the coupling of the field (that drives the variations in the fine structure constant) to the matter fields, on the space and time evolution of the fine structure constant.
 Publication:

arXiv eprints
 Pub Date:
 January 2004
 arXiv:
 arXiv:astroph/0401631
 Bibcode:
 2004astro.ph..1631M
 Keywords:

 Astrophysics
 EPrint:
 158 pages, 39 figures