In this paper we analyze the distribution of fertility rates across the world using parametric mixture models. We demonstrate the existence of twin peaks and the division of the world's countries in two distinct components: a high-fertility regime and a low fertility regime. Whereas the...

This paper proposes a theory for the gradual evolution of knowledge diffusion and growth over the very long run. A feedback mechanism between capital accumulation and the ease of knowledge diffusion explains a long epoch of (quasi-) stasis and an epoch of high growth linked by a gradual economic...