see for ZPE below:
Self propulsion and pairing process of new physics black holes, to form Herbig Haro systems with star ( galaxy or dwarf) formation in between.
NOT only the dual galaxy anchor black holes produce gas, or all the smaller supernova BHs, even the central merger black hole!
"Black hole hidden within its own exhaust.
ALMA image of the central region of galaxy NGC 1068
"But like any engine, a black hole can also emit exhaust."
That exhaust, astronomers discovered, is the likely source of the torus of material that effectively obscures the region around the galaxy's supermassive black hole from optical telescopes"