Conventional R&D-based growth theory argues that productivity growth is driven by population growth but the data …

This paper proposes a theory for the gradual evolution of knowledge diffusion and growth over the very long run. A …

literature, the present framework can reconcile R&D-based growth theory with the available empirical evidence. …

expectancy. We integrate the theory into a unified growth model and reestablish increasing life expectancy as an engine of long …