Growth in Economic Systems with Delay

We consider the role of the time delay parameter in basic models of economic growth. We study the Solow model with a time lag. We also consider the dynamical optimization in the Solow model. We demonstrate that, both for Solow's model and Cass' model with a delay, there appear cyclic fluctuations whose parameters we have calculated. These fluctuations have a consbant period and appear through the mechanism of the single Hopf bifurcation.