On the construction and measurement of conformal extensions of the Standard Model

Abstract

In this thesis, different conformal extensions of the Standard Model are studied. A general framework of quantum and thermal field theory is given to determine the effective potential up to one-loop order for general models. Also, it is found by studying symmetry-breaking patterns based on research from grand unified theories, that many models might have an strongly first-order electroweak phase transition, which can induce strong gravitational wave signals and baryogenesis. By determining multiple constraints on conformal extensions of the Standard Model from theoretical and experimental considerations, two new models are introduced: the adjoint fSU(N)cSM and the MfSU(N)cSM. For both the complete particle mass spectrum is calculated. Also, the already well-studied SU(2)cSM is considered as a benchmark model for a numerical program, CosmoTransitions. The program is used to study the electroweak phase transition of the three models and for the SU(2)cSM new results are found compared to previous work. For the two new models, unfortunately, no phase transition has been found, but a descriptive analysis is given for the temperature-dependence of their minima.