Description:

The insights gained from the first year and a half of JWST observations at high-redshift has transformed our understanding of early galaxy formation. For example, various surveys have identified substantially more bright galaxies at z > 9 than predicted from many semi-analytic models and simulations, while galaxy spectra are displaying emission lines (e.g. N IV]) rarely seen in the local Universe. Likewise, an unexpected number of broad spectral lines, indicative of potential AGN activity, have been detected, and some galaxies, for the first time, exhibit bright two-photon continuum emission suggesting an exceptionally top-heavy stellar initial mass function. In this talk, I will discuss the physics that may be driving some of this anomalous behaviour, focusing both on the observations and where current generations of simulations are both excelling and failing. 

Harley Katz, Assistant Professor, University of Chicago

Host: Allison Strom