Cosmological simulations allow us to study the emergence of structure in Universe: Starting from our understanding of the very early universe, we perform simulations of a wide range of scales: how dark matter collapses and forms the seeds of galaxies, how the large-scale filamentary network of galaxies arises from the counteracting forces of the expansion of the universe and the pull of gravity; how the largest collapsed objects in the universe - clusters of hundreds and thousands of galaxies - form and evolve and what we can learn about our universe from those most extreme objects; and how galaxies form as part of the large-scale structure that feeds them with gas. Finally, we study also how active galactic nuclei regulate the thermodynamic properties of gas in galaxy clusters and the impact they have on the formation of stars in massive galaxies.
Aside from astrophysical questions, we are also interested in developing numerical simulation techniques that allow us to answer questions about the universe both more precisely and more efficiently.
This movie shows the evolution of the gas during the
formation of a very massive galaxy cluster from the
RHAPSODY-G simulations. The gas density is shown in
gray colors with the gas temperature overlaid in
orange. The abundance and properties of these massive
systems contain a wealth of information about the
physics and cosmology of our Universe. The image is 17
Mpc/h wide, projection depth is 5 Mpc/h.
Visualization by Oliver Hahn
Simulation: Oliver Hahn, Davide Martizzi
This movie shows the formation of the cosmic
web of dark matter from random fluctuations in the early
universe. The intricate network of filaments hosts
dark matter halos, the most massive of them are
rendered in bright yellow hinting at the galaxies they
are thought to host in the LCDM cosmological model.
Visualization by Ralf Kaehler, Carter Emmart, Tom Abel for AMNH planetarium show "The Dark Universe"
Simulation: Tom Abel, Oliver Hahn