Constraining Galaxy Formation Physics with Digital Twins of Galaxy Clusters

by Olivia Mostow (Stockholm University / Princeton University)

Tuesday May 5, 2026, 11:00 AM → 12:00 PM Europe/Paris

Salle des séminaires

Galaxy clusters, as the most massive gravitationally bound systems in the Universe, are key probes of both cosmology and galaxy formation physics. While modern cosmological simulations successfully reproduce observed cluster scaling relations at the population level, these statistical agreements mask significant degeneracies in the modeling of unresolved baryonic processes, in particular feedback from active galactic nuclei (AGN).
Breaking these degeneracies requires moving beyond population statistics toward predictions at the level of individual objects. This is challenging in traditional cosmological simulations due to cosmic variance, but can be overcome using constrained simulations that reproduce the observed large-scale structure of the Local Universe.
Using the FLAMINGO–Manticore simulations, we construct digital twins of individual galaxy clusters and assess the ability of current galaxy formation models to reproduce their observed properties. We highlight both successes and systematic discrepancies, and discuss how object-level comparisons provide new constraints on baryonic physics. This approach opens a pathway toward more physically accurate models of galaxy formation by directly confronting simulations with the detailed properties of observed clusters.