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We study the space-time evolution of the fine structure constant, $alpha$, inside evolving spherical overdensities in a lambda-CDM Friedmann universe using the spherical infall model. We show that its value inside virialised regions will be significantly larger than in the low-density background universe. The consideration of the inhomogeneous evolution of the universe is therefore essential for a correct comparison of extragalactic and solar system limits on, and observations of, possible time variation in $alpha$ and other constants. Time variation in $alpha$ in the cosmological background can give rise to no locally observable variations inside virialised overdensities like the one in which we live, explaining the discrepancy between astrophysical and geochemical observations.
Early universe equations of state including realistic interactions between constituents are built up. Under certain reasonable assumptions, these equations are able to generate an inflationary regime prior to the nucleosynthesis period. The resulting
Recent measurements of the Cosmic Microwave Anisotropies power spectra measured by the Planck satellite show a preference for a closed universe at more than $99 %$ Confidence Level. Such a scenario is however in disagreement with several low redshift
This is a very informal report that gives further details on the evidence for a bubble universe based on an anomaly in the angular distribution of quasar magnitudes that was presented in a short paper in arXiv:1202.4433. This report addresses some co
We derive a luminosity distance formula for the varying speed of light (VSL) theory which involves higher order characteristics of expansion such as jerk, snap and lerk which can test the impact of varying $c$ onto the evolution of the universe. We s
There are many theories of quantum gravity, depending on asymptotic boundary conditions, and the amount of supersymmetry. The cosmological constant is one of the fundamental parameters that characterize different theories. If it is positive, supersym