Renormalizable, asymptotically free gravity without ghosts or tachyons

TL;DR

This paper develops a scale-invariant quadratic quantum gravity model that can be free of ghosts and tachyons, exhibits asymptotic freedom, and includes detailed analysis of symmetry breaking and dilaton mass in an SO(10) framework.

Contribution

It introduces a renormalizable, asymptotically free gravity theory without ghosts or tachyons, with detailed analysis of symmetry breaking and quantum corrections.

Findings

Emergence of ghost- and tachyon-free de Sitter solutions

Model exhibits complete asymptotic freedom

Calculated two-loop dilaton mass in SO(10) model

Abstract

We analyse scale invariant quadratic quantum gravity incorporating non-minimal coupling to a multiplet of scalar fields in a gauge theory, with particular emphasis on the consequences for its interpretation resulting from a transformation from the Jordan frame to the Einstein frame. The result is the natural emergence of a de Sitter space solution which, depending the gauge theory and region of parameter space chosen, can be free of ghosts and tachyons, and completely asymptotically free. In the case of an SO(10) model, we present a detailed account of the spontaneous symmetry breaking, and we calculate the leading (two-loop) contribution to the dilaton mass.