| Abstract: |
The nature of the dark sector remains one of the central open problems in fundamental physics. Dark matter is required to explain the formation of cosmic structure, while dark energy dominates the energy budget of the Universe and drives its accelerated expansion. Despite their importance, the microphysical origin of both components remains unknown. Cosmology offers a unique path to address this problem. Theoretical developments have expanded the space of viable dark-sector models, while precision measurements now enable increasingly stringent tests of new physics. At the same time, the emergence of cosmological tensions has highlighted the need for robust theoretical predictions and reliable statistical inference. This colloquium explores how theoretical modeling and cosmological inference work together to test the physics of the dark universe. It will discuss how theoretical cosmology can make this problem testable by connecting fundamental models of the dark universe to robust observational predictions, and how these predictions can be used to discriminate between competing scenarios and guide further theoretical developments. It will highlight results on dark matter and dark-sector phenomenology, including ultralight dark matter, as well as statistical methods designed to enable robust tests of the standard cosmological model and physics beyond it.
|
