Supersymmetry, supergravity, and String Theory based inflationary cosmology

Abstract

The aim of this thesis is to investigate and present an overview of inflationary theory. As part of this effort, the main motivations for cosmic inflation, which are known as problems in the standard big bang scenario, are reviewed. These problems are the "flatness problem", "horizon problem", and the "monopole problem." Analysis of inflation caused by a single scalar field rolling on a scalar potential is considered. This enables the introduction of the "slow-roll parameters" and their application. Since supersymmetry is considered a candidate beyond the standard model theory, we explore the connection between supersymmetry and the early universe. In order to incorporate gravity at energy scales of the early universe, supergravity is examined as well. Having considered inflation in the context of supersymmetry and supergravity, it is therefore natural to present the role of string theory in inflationary model building. As a result, axion monodromy is considered. Representative models are compared to analysis of precision measurements of the cosmic microwave background radiation. This comparison is achieved using observable derived constraints of the spectral index and tensor to scalar ratio.