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arXiv · 1410.8062

Inflationary cosmology from quantum Conformal Gravity

Petr Jizba·Hagen Kleinert·Fabio Scardigli
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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.

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Petr Jizba, Hagen Kleinert, Fabio Scardigli. 2015-05-10. Inflationary cosmology from quantum Conformal Gravity. https://doi.org/10.1140/epjc%2Fs10052-015-3441-6

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