Ghost anomalous dimension in asymptotically safe quantum gravity

We compute the ghost anomalous dimension within the asymptotic-safety scenario for quantum gravity. For a class of covariant gauge fixings and using a functional renormalization group scheme, the anomalous dimension ηc is negative, implying an improved UV behavior of ghost fluctuations. At the non-G...

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Bibliographic Details
Main Authors: Eichhorn, Astrid (Author) , Gies, Holger (Author)
Format: Article (Journal)
Language:English
Published: 5 May 2010
In: Physical review. D, Particles, fields, gravitation, and cosmology
Year: 2010, Volume: 81, Issue: 10
ISSN:1550-2368
DOI:10.1103/PhysRevD.81.104010
Online Access:Verlag, Volltext: http://dx.doi.org/10.1103/PhysRevD.81.104010
Verlag, Volltext: https://link.aps.org/doi/10.1103/PhysRevD.81.104010
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Author Notes:Astrid Eichhorn and Holger Gies
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Summary:We compute the ghost anomalous dimension within the asymptotic-safety scenario for quantum gravity. For a class of covariant gauge fixings and using a functional renormalization group scheme, the anomalous dimension ηc is negative, implying an improved UV behavior of ghost fluctuations. At the non-Gaussian UV fixed point, we observe a maximum value of ηc≃−0.78 for the Landau-deWitt gauge within the given scheme and truncation. Most importantly, the backreaction of the ghost flow onto the Einstein-Hilbert sector preserves the non-Gaussian fixed point with only mild modifications of the fixed-point values for the gravitational coupling and cosmological constant and the associated critical exponents; also their gauge dependence is slightly reduced. Our results provide further evidence for the asymptotic-safety scenario of quantum gravity.
Item Description:Gesehen am 25.02.2020
Physical Description:Online Resource
ISSN:1550-2368
DOI:10.1103/PhysRevD.81.104010