Chaos and Semiclassical Limit in Quantum Cosmology

TL;DR

This paper investigates the failure of the WKB approximation in a quantum cosmology model with chaotic features, questioning its validity for large universes and highlighting the emergence of small scale structures in the wave function.

Contribution

It demonstrates the breakdown of the WKB approximation in a chaotic quantum cosmology model, challenging its traditional interpretation in the field.

Findings

WKB approximation fails for large universes in the model

Breakdown pattern resembles semiclassical chaos phenomena

Small scale structures develop in the wave function

Abstract

In this paper we present a Friedmann-Robertson-Walker cosmological model conformally coupled to a massive scalar field where the WKB approximation fails to reproduce the exact solution to the Wheeler-DeWitt equation for large Universes. The breakdown of the WKB approximation follows the same pattern than in semiclassical physics of chaotic systems, and it is associated to the development of small scale structure in the wave function. This result puts in doubt the ``WKB interpretation'' of Quantum Cosmology.