We show that in the case of very massive (M > 108 M0 ) Kerr black holes with extreme ranges of angular momentum 1 ≥ a/M > 0.998, the possibility of photon-induced Penrose pair production (PPP) in the ergosphere is very plausible. The pairs that escape the ergosphere are very high energy and on the order of the GeV rest mass of the Penrose accreted protons which participate in the photon-induced pair production process. Application of this model to the case of quasistellar objects (QSOs) is shown to lead to reasonable predictions about their masses, lifetimes, and luminosities. The physical mechanism is very general, and also can be applied to other types of active galactic nuclei.
Leiter, D., Kafatos, M. (1978) Penrose Pair Production in Massive, Extreme Kerr Black Holes, Astrophysical Journal, Vol. 226:32-36. doi: 10.1086/156581