Quantum Cosmology: Effective Theory

TL;DR

This paper develops an effective theory framework for quantum cosmology, enabling systematic derivation of corrections to classical equations and addressing key conceptual issues like space-time structure and covariance.

Contribution

It introduces a systematic effective theory approach to quantum cosmology, incorporating space-time, covariance, and anomaly considerations for more testable predictions.

Findings

Framework allows derivation of quantum corrections to classical cosmology.

Addresses the problem of time and space-time structures in quantum cosmology.

Provides a basis for making quantum cosmology empirically testable.

Abstract

Quantum cosmology has traditionally been studied at the level of symmetry-reduced minisuperspace models, analyzing the behavior of wave functions. However, in the absence of a complete full setting of quantum gravity and detailed knowledge of specific properties of quantum states, it remained difficult to make testable predictions. For quantum cosmology to be part of empirical science, it must allow for a systematic framework in which corrections to well-tested classical equations can be derived, with any ambiguities and ignorance sufficiently parameterized. As in particle and condensed-matter physics, a successful viewpoint is one of effective theories, adapted to specific issues one encounters in quantum cosmology. This review presents such an effective framework of quantum cosmology, taking into account, among other things, space-time structures, covariance, the problem of time and the anomaly issue.