Chaos in Quantum Cosmology

TL;DR

This paper demonstrates that classical chaos in simple quantum cosmology models challenges the validity of standard quantum results, especially the WKB approximation, impacting our understanding of the universe's quantum behavior.

Contribution

It reveals the presence of deterministic chaos in minisuperspace models and discusses its implications for the validity of quantum cosmological approximations.

Findings

Classical minisuperspace models exhibit deterministic chaos.

Chaos leads to breakdown of the WKB approximation.

Standard quantum cosmology results may be unreliable due to chaos.

Abstract

Much of the foundational work on quantum cosmology employs a simple minisuperspace model describing a Friedmann-Robertson-Walker universe containing a massive scalar field. We show that the classical limit of this model exhibits deterministic chaos and explore some of the consequences for the quantum theory. In particular, the breakdown of the WKB approximation calls into question many of the standard results in quantum cosmology.