Non-marginal LTB-like models with inverse triad corrections from loop quantum gravity

TL;DR

This paper extends loop quantum gravity corrections to non-marginal LTB models, analyzing anomaly-free conditions and exploring the impact on singularity resolution and bouncing solutions in inhomogeneous cosmologies.

Contribution

It introduces an alternative anomaly-free quantization method for all LTB models, including non-marginal ones, and compares it with previous approaches.

Findings

Bounces are less common in inhomogeneous models compared to homogeneous ones.

Homogeneous solutions may be excluded by quantum effects in inhomogeneous models.

Non-marginal models show a higher likelihood of bouncing solutions.

Abstract

Marginal LTB models with corrections from loop quantum gravity have recently been studied with an emphasis on potential singularity resolution. This paper corroborates and extends the analysis in two regards: (i) the whole class of LTB models, including non-marginal ones, is considered, and (ii) an alternative procedure to derive anomaly-free models is presented which first implements anomaly-freedom in spherical symmetry and then the LTB conditions rather than the other way around. While the two methods give slightly different equations of motion, not altogether surprisingly given the ubiquitous sprawl of quantization ambiguities, final conclusions remain unchanged: Compared to quantizations of homogeneous models, bounces seem to appear less easily in inhomogeneous situations, and even the existence of homogeneous solutions as special cases in inhomogeneous models may be precluded by quantum effects. However, compared to marginal models, bouncing solutions seem more likely with non-marginal models.