Superstring Cosmology: An Investigation into Low Temperature Effective Gauss-Bonnet Corrections to the Einstein Field Equations in an Inflationary Scenario

Several problems with the inflationary cosmological model and the force coupling constants are addressed in the context of superstring theory. In order to simplify the field equations slightly, vacuum solutions are attempted. The solutions for several field equations are analyzed in order to obtain an inflationary universe that leads to a nearly static internal space. A solution is found when Gauss-Bonnet terms, as well as the Einstein terms, are used in the field equations, along with an exponential radii function for a ten dimensional product space. The solutions lead to a three-phase universe that might describe our very early universe. A first phase contains expanding internal and external space dimensions. In the second phase the internal dimensions begin to contract while the external dimensions continue to expand. In the last phase, the internal dimensions become nearly static, thus leading to the nearly constant force couplings observed today. These solutions are compared to the observational constraint equations, and it is doubtful these solutions characterize the temporal change in the couplings. It is found to be difficult to be able to meet these constraints in a manner that is consistent with the current age of the universe. In addition, it appears that the non-vacuum solution may offer a more accurate description of the early universe