Chaos in a closed Friedmann-Robertson-Walker universe: An imaginary approach

In this work we study the existence of mechanisms of transition to global chaos in a closed Friedmann-Robertson-Walker universe with a massive conformally coupled scalar field. We propose a complexification of the radius of the universe so that the global dynamics can be understood. We show numerically the existence of heteroclinic connections of the unstable and stable manifolds to periodic orbits associated to the saddle-center equilibrium points. We find two bifurcations which are crucial in creating non-collapsing universes both in the real and imaginary version of the models. The techniques presented here can be employed in any cosmological model.