Singularity resolution from polymer quantum matter
We study the polymeric nature of quantum matter fields using the example of a Friedmann-Lemaitre-Robertson-Walker universe sourced by a minimally coupled massless scalar field. The model is treated in the symmetry reduced regime via deparametrization techniques, with the scale factor playing the role of time. Subsequently the remaining dynamic degrees of freedom are polymer quantized. The analysis of the resulting dynamic shows that the big bang singularity is resolved, although with the form of the resolution differing significantly from that of the models with matter clocks: dynamically, the singularity is made passable rather than avoided. Furthermore, the results of the genuine quantum analysis expose crucial limitations to the so-called effective dynamics in loop quantum cosmology when applied outside of the simplest isotropic settings.