 The hybrid perovskite CH3NH3PBI3, MAPI, has long minority carrier lifetimes and diffusion lengths due to slow recombination from a spin-split indirect gap, which is caused by large internal electric fields acting on spin orbit coupled band extrema. The fundamental gap in MAPI is indirect, and radiative recombination is reduced by a factor of more than 350 compared to direct gap behavior at operating conditions. This article was authored by Puyya Azarhush, Scott McKetchney, Jarvist M. Frost and others.