English

Gauge-invariant bounce from loop quantum gravity

General Relativity and Quantum Cosmology 2020-03-31 v2 High Energy Physics - Theory

Abstract

We present a gauge-invariant treatment of singularity resolution using loop quantum gravity techniques with respect to local SU(2) transformations. Our analysis reveals many novel features of quantum geometry which were till now hidden in models based on non-gauge-invariant discretizations. Quantum geometric effects resolve the big bang singularity replacing it with a non-singular bounce when spacetime curvature reaches Planckian value. The bounce is found to be generically asymmetric in the sense that pre-bounce and post-bounce branches are not mirrored to each other and effective constants, such as Newton's constant, are rescaled across the bounce. Furthermore, in the vicinity of the bounce, minimally coupled matter behaves as non-minimally coupled. These ramifications of quantum geometry open a rich avenue for potential phenomenological signatures.

Keywords

Cite

@article{arxiv.1906.02759,
  title  = {Gauge-invariant bounce from loop quantum gravity},
  author = {Klaus Liegener and Parampreet Singh},
  journal= {arXiv preprint arXiv:1906.02759},
  year   = {2020}
}

Comments

12 pages, 2 figures. Published version in Classical and Quantum Gravity

R2 v1 2026-06-23T09:45:58.991Z