Population dynamics, urbanisation without growth, and the rise of megacities

This study examines the complex interactions between population dynamics, urbanization, and economic growth, particularly in the context of developing countries and megacities. The objective is to develop a theoretical model that captures these interactions and analyze the implications for productivity and migration patterns. The methodology involves constructing a dynamic model that distinguishes between rural and urban areas within a developing country, while considering the effects of internal migration and differing production functions for each area. The model is utilized to explore the impact of factors such as GDP per capita, urban growth rates, and population growth on the overall economic landscape. Key results indicate that urbanization does not necessarily lead to economic growth, with evidence suggesting that migration decisions are predominantly influenced by the marginal product of labor across regions. Furthermore, the findings reveal substantial variation in the economic outcomes of urbanization efforts, underscoring the need for tailored policy interventions. Through this model, the study contributes to the understanding of how megacity development can be aligned with sustainable growth principles, ultimately providing insights for policymakers in developing regions.