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Globular clusters are massive star clusters that formed in high-redshift galaxies and remained gravitationally bound until the present. They serve as tracers of most active episodes of galactic star formation and allow us to reconstruct the assembly history of the Milky Way and nearby galaxies. I will describe a long-term program to model the formation and disruption of globular clusters throughout cosmic time, using a combination of cosmological simulations with adaptive mesh refinement and accurate semi-analytic modeling. These simulations predicted that massive star clusters should be the dominant stellar populations of high-redshift galaxies, as has now been confirmed by JWST observations of strongly lensed galaxies. The feedback of massive clusters regulates the star formation history of their host galaxies and their observability, and the shape of the cluster mass function serves as an indicator of burstiness of the galactic star formation. The semi-analytical model allows us to follow the long-term evolution of these clusters and provides evidence that the massive clusters observed at high redshift are true progenitors of old globular clusters in the local universe. We have also developed efficient algorithms for detecting stellar streams created by disrupting globular clusters, which revealed tens of previously undiscovered streams in the Gaia data. Mock catalogs of the predicted populations of survived Galactic globular clusters and stellar streams from disrupted clusters are available for all interested researchers.

BIO

Professor Gnedin obtained his Master of Science degree from St Petersburg State Technical University in 1994 and Ph.D. from Princeton University in 1999. He held postdoctoral fellowship appointments at Cambridge University, Space Telescope Science Institute, and Ohio State University. He has been a professor at University of Michigan since 2006.

Host: Hui Li