Does evidence challenge the DSGE model?

DSGE are for a time the favorite models in the simulation of monetary policies at the central banks. Two of its basic assumptions are discussed in this paper: (a) the absence of endogenous nonlinearities and the exogenous nature of shocks and (b) the persistence of or the return to equilibrium after a shock, or the absence of dynamics. Our analysis of complex financial markets, using historical data of S&P500, suggests otherwise that financial regimes endogenously change and that equilibrium is an artifact.