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arXiv · 0907.1828

Asymptotically free scalar curvature-ghost coupling in Quantum Einstein Gravity

Astrid Eichhorn·Holger Gies·Michael M. Scherer
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Abstract

We consider the asymptotic-safety scenario for quantum gravity which constructs a non-perturbatively renormalisable quantum gravity theory with the help of the functional renormalisation group. We verify the existence of a non-Gaussian fixed point and include a running curvature-ghost coupling as a first step towards the flow of the ghost sector of the theory. We find that the scalar curvature-ghost coupling is asymptotically free and RG relevant in the ultraviolet. Most importantly, the property of asymptotic safety discovered so far within the Einstein-Hilbert truncation and beyond remains stable under the inclusion of the ghost flow.

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Astrid Eichhorn, Holger Gies, Michael M. Scherer. 2009-07-10. Asymptotically free scalar curvature-ghost coupling in Quantum Einstein Gravity. https://doi.org/10.1103/physrevd.80.104003

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