Classical analogous of quantum cosmological perfect fluid models

TL;DR

This paper demonstrates that quantum cosmological models with perfect fluids can be classically mimicked by a system including a repulsive fluid, leading to singularity-free solutions and insights into the nature of quantization.

Contribution

It establishes a classical analogy for quantum perfect fluid cosmological models, revealing a repulsive fluid component and analyzing stability conditions.

Findings

Quantum models are equivalent to classical systems with a repulsive fluid.

Presence of an anti-gravity phase affects stability.

Models predict singularity-free cosmological solutions.

Abstract

Quantization in the mini-superspace 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 that such models are equivalent to a classical system where, besides the perfect fluid, a repulsive fluid with an equation of state $p_Q = \rho_Q$ is present. This leads to speculate on the true nature of this quantization procedure. A perturbative analysis of the classical system reveals the condition for the stability of the classical system in terms of the existence of an anti-gravity phase.