A dramatic success of modern cosmology is the explanation of the origins of complex structures like galaxies as being rooted in physical processes that took place in the very early Universe. These initially microscopic fluctuations in energy density evolved through gravitation in an expanding Universe to form galaxies, which trace the cosmic web of large scale structure we observe today.
In this Research Unit, we use modern theoretical and observational methods to test the paradigm of structure formation, to measure cosmological parameters and to probe models of gravity.
We exploit surveys of large-scale structure, such as DES, DESI, LSST and Euclid to quantify the large scale structure and its evolution over time using millions of galaxies as tracers. Furthermore we use the distribution in space, mass and time of galaxy clusters as observed via their X-ray signatures with the eRosita instrument on board the SRG satellite or from optical and near-infrared surveys such as LSST and the Euclid satellite to test structure formation models. Further, we probe the physics of the very early Universe with observations of the polarization anisotropy of the cosmic microwave background with, for example, the LiteBIRD satellite and the CCAT-p telescope. This research is enriched by detailed theoretical studies of the structure formation process that employs modern perturbation theory and by complex computer simulations of the structure formation process.