Astronomy Colloquium

The EAGLE (Evolution and Assembly of Galaxies and their Environments) project is a suite of hydrodynamic simulations of the Universe. The simulations, include the full range of baryonic physics including metal dependent gas cooling star formation, supernovae, black hole formation. The resolution of the simulations is sufficient to resolve the onset of the Jeans instability in galactic disks, allowing us to study the formation of galaxies in detail.  At the same time the largest calculation simulates a volume that is 100 Mpc on each side, allowing us to study galaxy formation across  the full range of galaxy environments from the isolated dwarves to rich galaxy clusters.

A key philosophy of the simulations has been to use the simplest possible sub-grid models for star formation and black hole accretion, and for feedback from supernovae and AGN. Efficient feedback is achieved without hydrodynamic decoupling of particles. The small number of parameters in these models are calibrated by requiring that the simulations match key observed properties of local galaxies.  Having set the parameters using the local Universe, I will show that the simulations reproduce the observed evolution of galaxy properties extremely well.

The resulting universe provides us with deep insight into the formation of galaxies and black holes. In particular, we can use the simulations to understand the relationship between local galaxies and their progenitors at higher redshift and to understand the role of interactions between galaxies and the AGN that they host. I will present an overview of some of the most important results from the project.