Dark Matter models in light of Effective Field Theories, the Baryon Asymmetry, and Neutrino Properties

This thesis addresses several observations in nature that cannot be explained by the Standard Model of particle physics. The overarching topic is the theoretical description of dark matter (DM) which constitutes the framework for two further conundrums: the baryon asymmetry of the Universe and neutrino masses. In the context of effective field theories (EFTs) we first compare an extended DM EFT to UV theories and investigate its range of validity. Making use of the power of EFTs in the next chapter, we augment the Inert Doublet Model by a CP-violating effective operator which can thereby explain the imbalance between matter and antimatter in the Universe and simultaneously account for DM while eluding constraints from electron electric dipole moment searches and DM direct detection. We further discuss possible UV realizations of the effective operators. Lastly, we turn to the unknown origin of neutrino masses and connect this puzzle to DM via the analysis of potential DM indirect detection signals as well as of collider signatures that offer insights into the free neutrino oscillation parameters and the neutrino mass hierarchy. We find potential for synergies between the different experimental approaches to determine neutrino properties.