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Effective average action and nonperturbative renormalization group equation in higher derivative quantum gravity

L. N. Granda·S. D. Odintsov
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Abstract

We study the exact renormalization group (RG) in $R^2$-gravity in the effective average action formalism using the background field method. The truncated evolution equation (where truncation is made to low-derivatives functionals space) for such a theory in a de Sitter background leads to a set of nonperturbative RG equations for cosmological and gravitational coupling constants. The gauge dependence problem is solved by working in the physical Landau-De Witt gauge corresponding to gauge-fixing independent effective action. Approximate solution of nonperturbative RG equations reveals the appearence of antiscreening or screening behaviour of Newtonian coupling, depending on the higher-derivatives coupling constants. The existence of unstable UV fixed points is also mentioned.

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L. N. Granda, S. D. Odintsov. 1998-05-27. Effective average action and nonperturbative renormalization group equation in higher derivative quantum gravity. https://arxiv.org/abs/gr-qc/9801026

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