This paper develops an open economy growth model in which firm heterogeneity increases the gains from trade. Technology spillovers from incumbent firms to entrants cause the productivity threshold for firm survival to grow over time as competition becomes tougher. By raising the profits of...

This paper studies the origins and consequences of international technology gaps. I develop an endogenous growth model where R&D efficiency varies across countries and productivity differences emerge from firm-level technology investments. The theory characterizes how innovation and learning...