Infrared limit of quantum gravity

• Verfasst von: Wetterich, Christof [VerfasserIn]
• Titel: Infrared limit of quantum gravity
• Verf.angabe: C. Wetterich, Institut für Theoretische Physik, Universität Heidelberg
• E-Jahr: 2018
• Jahr: 25 July 2018
• Umfang: 11 S.
• Fussnoten: Gesehen am 12.11.2020
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2018
• Band/Heft Quelle: 98(2018,3) Artikel-Nummer 026028, 11 Seiten
• ISSN Quelle: 2470-0029
• DOI: doi:10.1103/PhysRevD.98.026028
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1584046767

Abstract

We explore the infrared limit of quantum gravity in the presence of a cosmological constant or effective potential for scalar fields. For a positive effective scalar potential, one-loop perturbation theory around flat space is divergent due to an instability of the graviton propagator. Functional renormalization solves this problem by a flow of couplings avoiding instabilities. This leads to a graviton barrier limiting the maximal growth of the effective potential for large values of scalar fields. In the presence of this barrier, variable gravity with a field dependent Planck mass can solve the cosmological constant problem by a cosmological runaway solution. We discuss the naturalness of tiny values of the cosmological constant and cosmon mass due to a strong attraction towards an infrared fixed point.