Super-renormalizable Gravity

TL;DR

This paper reviews super-renormalizable gravity theories with non-polynomial form factors that avoid ghosts, improve high-energy behavior, and produce singularity-free black hole and cosmological solutions.

Contribution

It introduces a class of higher derivative gravity theories with non-polynomial form factors that are super-renormalizable and free of ghosts, with classical solutions that are singularity-free.

Findings

Theories are super-renormalizable with only one-loop divergences.

Black holes and cosmological solutions are free of singularities.

Form factors improve the quantum behavior of gravity.

Abstract

We review a class of higher derivative theories of gravity consistent at quantum level. This class is marked by a non-polynomal entire function (form factor), which averts extra degrees of freedom (including ghosts) and improves the high energy behaviour of the loop amplitudes. By power counting arguments, it is proved that the theory is super-renormalizable, i.e. only one-loop divergences survive. At classical level, black holes and cosmological solutions are singularity free.