A Comparative Theoretical Macroeconomic Analysis of the United States and China through the Lens of the Solow Growth Model: Population Dynamics, State Strategies, and Technological Progress

This paper explores the macroeconomic trajectories of the United States and China using the Solow growth model, focusing on capital accumulation, labour force dynamics, and technological progress. The analysis highlights the distinct challenges and opportunities arising from population characteristics, including ageing populations and demographic transitions, and evaluates state dynamics and institutional frameworks influencing economic strategies. The findings reveal that while the United States benefits from technological innovation and a balanced demographic structure, it faces rising dependency ratios. Conversely, China confronts significant demographic and structural headwinds but leverages state-driven initiatives and rapid urbanisation. Policy recommendations address demographic adjustments, productivity enhancement, and structural reforms to sustain long-term growth.