English

A QCD analogy for quantum gravity

High Energy Physics - Theory 2016-06-15 v2 General Relativity and Quantum Cosmology

Abstract

Quadratic gravity presents us with a renormalizable, asymptotically free theory of quantum gravity. When its couplings grow strong at some scale, as in QCD, then this strong scale sets the Planck mass. QCD has a gluon that does not appear in the physical spectrum. Quadratic gravity has a spin-2 ghost that we conjecture does not appear in the physical spectrum. We discuss how the QCD analogy leads to this conjecture and to the possible emergence of general relativity. Certain aspects of the QCD path integral and its measure are also similar for quadratic gravity. With the addition of the Einstein-Hilbert term, quadratic gravity has a dimensionful parameter that seems to control a quantum phase transition and the size of a mass gap in the strong phase.

Keywords

Cite

@article{arxiv.1512.05305,
  title  = {A QCD analogy for quantum gravity},
  author = {Bob Holdom and Jing Ren},
  journal= {arXiv preprint arXiv:1512.05305},
  year   = {2016}
}

Comments

27 pages, 3 figures, matches published version

R2 v1 2026-06-22T12:11:35.506Z