Regime-Switching Sunspot Equilibria in a One-Sector Growth Model with Aggregate Decreasing Returns and Small Externalities

Abstract

This paper shows that regime-switching sunspot equilibria easily arise in a one-sector growth model with aggregate decreasing returns and arbitrarily small externalities. We construct a regime-switching sunspot equilibrium in the case where the utility function of consumption is linear. We also construct a stochastic optimal growth model whose optimal process is a regime-switching sunspot equilibrium of the original economy in the case where there is no capital externality. We illustrate our results with numerical examples.