We consider an economy in which the technology exhibits nonconvexities due to fixed costs associated with production. Taking into account the incentives for investment to decrease the fixed costs, we characterize the circumstances under which an underdeveloped economy can catch up with the...

We address the fundamental issues of existence and efficiency of an equilibrium in a Ramsey model with many agents, where agents have heterogenous discounting, elastic labor supply and face borrowing con- straints. The existence of rational bubbles is also tackled. In the first part, we prove...