Matter in inhomogeneous loop quantum cosmology: the Gowdy $T^3$ model

TL;DR

This paper quantizes the Gowdy T^3 cosmological model with matter using a hybrid loop and Fock approach, resolving singularities and enabling the study of inhomogeneities' effects on flat FRW universes.

Contribution

It introduces a hybrid quantization method for the Gowdy T^3 model with matter, revealing quantum resolution of singularities and the emergence of flat FRW solutions.

Findings

Quantum resolution of classical singularities.

Existence of flat FRW solutions with matter.

Potential to study anisotropies and inhomogeneities effects.

Abstract

We apply a hybrid approach which combines loop and Fock quantizations to fully quantize the linearly polarized Gowdy $T^3$ model in the presence of a massless scalar field with the same symmetries as the metric. Like in the absence of matter content, the application of loop techniques leads to a quantum resolution of the classical cosmological singularity. Most importantly, thanks to the inclusion of matter, the homogeneous sector of the model contains flat Friedmann-Robertson-Walker (FRW) solutions, which are not allowed in vacuo. Therefore, this model provides a simple setting to study at the quantum level interesting physical phenomena such as the effect of the anisotropies and inhomogeneities on flat FRW cosmologies.