Consistent Loop Quantum Cosmology

TL;DR

This paper critically examines loop quantum cosmology models, showing many are inconsistent with quantum geometry effects, especially regarding critical densities and black hole interiors, leading to revised constraints on these models.

Contribution

It identifies and rules out a broad class of loop quantum cosmology models based on quantum geometry consistency, refining the understanding of critical densities and black hole interiors.

Findings

Critical density for universe bounce must be below Planck density

Many models of black hole interiors are inconsistent with quantum geometry effects

Certain loop quantum cosmology models are ruled out due to inconsistency

Abstract

A consistent combination of quantum geometry effects rules out a large class of models of loop quantum cosmology and their critical densities as they have been used in the recent literature. In particular, the critical density at which an isotropic universe filled with a free, massless scalar field would bounce must be well below the Planck density. In the presence of anisotropy, no model of the Schwarzschild black hole interior analyzed so far is consistent.