Classical analogous of quantum cosmological perfect fluid models

Quantization in the minisuperspace of a gravity system coupled to a perfect fluid, leads to a solvable model which implies singularity free solutions through the construction of a superposition of the wavefunctions. We show t hat such models are equivalent to a classical system where, besides the per fect fluid, a repulsive fluid with an equation of state p(Q) = rho (Q) is p resent. This leads to speculate on the true nature of this quantization pro cedure. A perturbative analysis of the classical system reveals the conditi on for the stability of the classical system in terms of the existence of a n anti-gravity phase. (C) 2001 Elsevier Science B.V, All rights reserved.