Renormalizable, asymptotically free gravity without ghosts or tachyons

Understand

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.