Which Came First: Supermassive Black Holes or Galaxies? Insights from JWST

Insights from JWST observations suggest that active galactic nuclei feedback evolved from a short-lived, high-redshift phase in which radiatively cooled turbulence and/or momentum-conserving outflows stimulated vigorous early star formation (“positive” feedback), to late, energy-conserving outflows that depleted halo gas reservoirs and quenched star formation. The transition between these two regimes occurred at z ∼ 6, independently of galaxy mass, for simple assumptions about the outflows and star formation process.