The origins of radio emission from [radio-"quiet"] AGN

Abstract: One of the more puzzling aspects of active galactic nuclei is the dominant physical origin of their radio emission. For radio-loud objects, it's clear that the dominant origin is the AGN radio-jet. But for radio-quiet objects, recent literature results demonstrate an on-going controversy. Potential sources of radio emission include black hole spin, (scaled-down) AGN jets, shocks from AGN driven winds, and host galaxy star formation. In reality, all of these may contribute, but the question remains as to which one (if any) is the dominant source. I will review what is understand about radio-loud and radio quiet AGNs, discuss the ongoing controversy, and present possible next steps.Slides from presentation at the May 2018 astronomy conference "The radio and X-ray connection in accreting objects" held in Monopoli, Italy