  More than three decades ago quadratic gravity was found to present a
perturbative, renormalizable and asymptotically free theory of quantum gravity.
Unfortunately the theory appeared to have problems with a spin-2 ghost. In this
essay we revisit quadratic gravity in a different light by considering the case
that the asymptotically free interaction flows to a strongly interacting
regime. This occurs when the coefficient of the Einstein-Hilbert term is
smaller than the scale $\Lambda_{\mathrm{QG}}$ where the quadratic couplings
grow strong. Here QCD provides some useful insights. By pushing the analogy
with QCD, we conjecture that the nonperturbative effects can remove the naive
spin-2 ghost and lead to the emergence of general relativity in the IR.

High Energy Physics - Theory;General Relativity and Quantum Cosmology