We start the report with a brief review of Einsteins’ general relativity, and introduce the Einstein equation, which provide the theoretical framework for cosmological studies. We then study Friedmann Robertson Walker spacetimes, which are obtained from the Einstein equations by means of the cosmological principle. We will briefly introduce the standard hot Big Bang picture, which is consistent with an expanding universe, and see that this leads to the so called flatness and horizon problem. We will see that these issues can be resolved, if one assumes an epoch of rapid accelerated expansion, known as inflation, prior to the hot Big Bang.
In the second part of the report we describe two models of composite inflation. The first model known as Minimal Composite Inflation, uses models of Minimal Walking Technicolor as templates. The inflationary order parameter emerges as a composite state, like the composite Higgs does in models of dynamical electroweak symmetry breaking. In the second model known as Glueball inflation, the inflation emerges as the lightest glueball field of a pure Yang-Mills theory. In both models we consider the inflationary potential as a low energy effective description of the underlying strong dynamics. We will see that it is possible to have a succesful inflationary epoch in both models.
The thesis contains some unpublished results and cannot currently be downloaded from our home page. Please contact Jakob Jark Jørgensen for further information.