Organizers:

Greg Bryan, Columbia University
Christoph Pfrommer, Leibniz Institute for Astrophysics
Mateusz Ruszkowski, University of Michigan
Ellen Zweibel, University of Wisconsin

Understanding the processes underlying galaxy formation is one of the most important challenges in astrophysics. Unresolved questions include the disconnect between the short time scale of gas collapse on small scales and the long time scale for galaxy evolution, as well as the mechanism responsible for ejecting mass, momentum, and energy out of galaxies (or preventing their infall) in a way that matches the observed scaling relations. Recent progress in the field of astrophysical feedback strongly suggests that relativistic particle populations called cosmic rays may play a crucial role in controlling these processes in and around galaxies and galaxy clusters. However, the strength of cosmic ray feedback depends very sensitively on the dynamical coupling of cosmic rays to the plasma, a complete understanding of which will require novel plasma physics insights. Connecting detailed simulations to multi-frequency and multi-messenger observations will be of paramount importance for elucidating the underlying physics. Hence, the goal of this workshop is to bring together an interdisciplinary group of scientists studying plasma physics, cosmic ray propagation in the Milky Way, high-energy astrophysics (embracing radio, X-ray, and gamma-ray astronomy), galaxy formation, and evolution of galaxy clusters in order to learn from each other, facilitate collaborations among the participants, and advance the field into an era of predictive galaxy formation.