If you are not familiar with this model, you may find more information from Khan Academy. This brings out the Keynesian beliefs versus the Classical. Most textbooks identify the Classical view with the long-run equilibrium, which tends to be fixed at a certain unemployment and GDP level and some inflation. On the other hand, the Keynesian view is usually associated with a series of short-run equilibriums which eventually convert to the long-run Classical equilibrium. Do you believe this is the case for our current economic condition?