High-redshift radio galaxies: at the crossroads

Abstract

The next generation of surveys of extragalactic radio sources will be dominated by different types of objects than the jetted-AGN that dominate surveys like 3C, 6C and 7C. Before radio astronomy becomes concentrated on the new types of object, it is vital that we understand the cosmological importance of the jetted-AGN that have been studied for many years. I argue that, as observational manifestations of Eddington-tuned outflow events, these objects may have more significance for galaxy/cluster formation and evolution than is typically appreciated. Outstanding problems in galaxy formation may be solved by cosmological simulations in which this type of outflow, as well as other types associated with weaker jets, are properly taken into account. I will highlight areas of ignorance which are currently hindering attempts to do this.