Ghost anomalous dimension in asymptotically safe quantum gravity

• Verfasst von: Eichhorn, Astrid [VerfasserIn]
• Verfasst von: Gies, Holger [VerfasserIn]
• Titel: Ghost anomalous dimension in asymptotically safe quantum gravity
• Verf.angabe: Astrid Eichhorn and Holger Gies
• E-Jahr: 2010
• Jahr: 5 May 2010
• Umfang: 12 S.
• Fussnoten: Gesehen am 25.02.2020
• Titel Quelle: Enthalten in: Physical review / D
• Ort Quelle: [S.l.] : Soc., 1970
• Jahr Quelle: 2010
• Band/Heft Quelle: 81(2010,10) Artikel-Nummer 104010, 12 Seiten
• ISSN Quelle: 1550-2368
• ISSN Quelle: 1089-4918
• DOI: doi:10.1103/PhysRevD.81.104010
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1569735115

Abstract

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.