Diploma thesis |
||||
|
Download my diploma thesis in PostScript or PDF format:
DIPLOMARBEITPhase Transition of a Scalar Field Theory in the Early Universe ausgeführt am Institut für Theoretische Physik der Technischen Universität Wien
Abstract:Measurements of the cosmic microwave background radiation show a primary inhomogeneity in the temperature distribution of the order of $ \delta T/T\sim 10^{-5}$. The inflationary theory explains this inhomogeneity to be primeval quantum fluctuations expanded to galactic scales. Inflation is driven by the phase transition of a scalar field. In this work we analyze the non-equilibrium evolution of the effective scalar field mass through a phase transition in an expanding space-time background starting from an initial thermal equilibrium. The real-time formalism for a curved background metric is used to express the propagator in terms of mode functions. The one-loop mass correction is calculated from the Green function. A WKB-like approximation is applied to the resulting system of differential equations and an analytical expression for the scalar field mass is found in the high-temperature limit. Comparing this result to numerical calculations, we find that the analytical expression describes the scalar field mass pretty accurately far beyond the first classical turning point of the lowest mode function. Download:
|
|||
|