Tyler Cowen pushes Real Business Cycle Theory (RBC theory) - from Wikipedia:

According to RBC theory, business cycles are therefore "real" in that they do not represent a failure of markets to clear but rather reflect the most efficient possible operation of the economy, given the structure of the economy. RBC theory differs in this way from other theories of the business cycle such as Keynesian economics and Monetarism that see recessions as the failure of some market to clear.

RBC theory is associated with freshwater economics (the Chicago school of economics in the neoclassical tradition).

The article links to a 1986 piece by Larry Summers titled: Some Skeptical Observations on Real Business Cycle Theory.