We examine the conditions under which steady states with low real interest rates—real rates substantially below the output growth rate—exist in an overlapping generations model with production, capital accumulation, a labor-leisure trade-off, technological progress, and agents who live for many periods. The number of periods in an agent's life (n) is left open for much of the analysis and determines the temporal interpretation of a time period. The qualitative properties of the model are largely invariant to different values of n. We find that two low real interest rate steady states exist for empirically plausible values of the parameters of the model. Outside liabilities such as fiat currency or unbacked government debt are valued in one of these steady states.
We introduce, into a version of the Real Business Cycle model, mild increasing returns-to-scale. These increasing returns-to-scale occur as a consequence of sector specific externalities, that is externalities where the output of the consumption and investment sectors have external effects on the output of firms within their own sector. Keeping the production technologies for both sectors identical for expositional simplicity, we show that indeterminacy can easily occur for parameter values typically used in the real business cycle literature, and in contrast to some earlier literature on indeterminacies, for externalities mild enough so that labor demand curves are downward sloping.