The link between halo assembly and environment revealed by Graph Neural Networks, @Cosmic Horizons Conference

Understanding the joint evolution of galaxies and halos is central to galaxy evolution and cosmology. Using Graph Neural Networks, I will show that galaxy properties can be predicted equally well from a halo’s spatial environment or its assembly history, across both hydrodynamic and semi-analytic simulations. We also measure the characteristic scale needed to constrain each parameter, and determine the physical reason for the value of these scales.