Inflationary cosmology from quantum Conformal Gravity

TL;DR

This paper demonstrates that quantum Conformal Gravity can naturally produce an inflationary model similar to Starobinsky's, with implications for cosmic inflation consistent with recent observational data.

Contribution

It introduces a novel approach to quantum Conformal Gravity that generates inflationary dynamics through metric fluctuations and scalar fields, linking theory with cosmological observations.

Findings

Spontaneous generation of a Starobinsky-like inflationary model.

A relation between Starobinsky's parameter and the cosmological constant.

Compatibility with PLANCK and BICEP2 data.

Abstract

We analyze the functional integral for quantum Conformal Gravity and show that with the help of a Hubbard-Stratonovich transformation, the action can be broken into a local quadratic-curvature theory coupled to a scalar field. A one-loop effective action calculation reveals that strong fluctuations of the metric field are capable of spontaneously generating a dimensionally transmuted parameter which in the weak-field sector of the broken phase induces a Starobinsky-type f(R)-model with a gravi-cosmological constant. A resulting non-trivial relation between Starobinsky'sparameter and the cosmological constant is highlighted and implications for cosmic inflation are briefly discussed and compared with recent PLANCK and BICEP2 data.