Production often causes pollution as a by-product. Once pollution problems become too severe, regulation is introduced by political authorities which forces the economy to make a transition to cleaner production processes. We model this transition as a change in "general purpose technology"...

Though the environmental Kuznets curve (EKC) was originally developed to model the ambient concentrations of pollutants, most subsequent applications have focused on pollution emissions. Yet, it seems more likely that economic growth could eventually reduce the concentrations of local pollutants...