Paul Maximilian Ritschel

• This cumulative dissertation in theoretical macroeconomics presents five articles on deterministic, analytically tractable overlapping-generations models with two-period-lived agents and production. The microeconomic foundations are rooted in contract and game theory, while the analysis of macroeconomic dynamics builds on dynamical systems theory. Article 1 establishes that financial intermediation which provides efficient risk sharing cannot generate endogenous fluctuations. Article 2 examines how competition in the banking sector affects economic growth and welfare in the real sector. Article 3 investigates the impact of market power and strategic interaction in the capital market on savings, capital accumulation, and the qualitative dynamics. Article 4 introduces a novel parameterization of the production-possibility frontier in terms of wage-rental ratios that can enhance both the generality and tractability of two-sector growth models and allows for a refinement of the Rybczynski theorem. Building on this parameterization, Article 5 develops a tractable two-sector model with intergenerational pollution externalities to study the role of fiscal policy in steering the green transformation of an economy. The findings of this dissertation contribute to a deeper understanding of the determinants of economic growth, the sources of real business cycles, and normative welfare implications, while also providing recommendations for policymakers.