The trouble with asymptotically safe inflation

  • Chao Fang
  • Qing-Guo HuangEmail author
Regular Article - Theoretical Physics


In this paper we investigate the perturbation theory of asymptotically safe inflation and we find that all modes of gravitational waves perturbation become ghosts in order to achieve a large enough number of e-folds. Formally we can calculate the power spectrum of gravitational waves perturbation, but we find that it is negative. It indicates that there is serious trouble with asymptotically safe inflation.


Ghost Asymptotic Safety Renormalization Group Flow Einstein Hilbert Term Effective Coupling Constant 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



QGH would like to thank Henry Tye for helpful discussions. This work is supported by the project of Knowledge Innovation Program of Chinese Academy of Science and a grant from NSFC (grant No. 10975167).


  1. 1.
    S. Weinberg, in Understanding the Fundamental Constituents of Matter, ed. by A. Zichichi (Plenum, New York, 1977) Google Scholar
  2. 2.
    S. Weinberg, in General Relativity, an Einstein Centenary Survey, ed. by S. Hawking, W. Israel (Cambridge University Press, Cambridge, 1979) Google Scholar
  3. 3.
    M. Niedermaier, M. Reuter, The asymptotic safety scenario in quantum gravity. Living Rev. Relativ. 9, 5 (2006) ADSGoogle Scholar
  4. 4.
    A. Codello, R. Percacci, C. Rahmede, Ultraviolet properties of f(R)-gravity. Int. J. Mod. Phys. A 23, 143 (2008). arXiv:0705.1769 [hep-th] ADSCrossRefGoogle Scholar
  5. 5.
    A. Codello, R. Percacci, C. Rahmede, Investigating the ultraviolet properties of gravity with a Wilsonian renormalization group equation. Ann. Phys. 324, 414 (2009). arXiv:0805.2909 [hep-th] MathSciNetADSzbMATHCrossRefGoogle Scholar
  6. 6.
    D. Benedetti, P.F. Machado, F. Saueressig, Asymptotic safety in higher-derivative gravity. Mod. Phys. Lett. A 24, 2233 (2009). arXiv:0901.2984 [hep-th] ADSzbMATHCrossRefGoogle Scholar
  7. 7.
    D. Benedetti, P.F. Machado, F. Saueressig, Taming perturbative divergences in asymptotically safe gravity. Nucl. Phys. B 824, 168 (2010). arXiv:0902.4630 [hep-th] MathSciNetADSzbMATHCrossRefGoogle Scholar
  8. 8.
    A. Bonanno, M. Reuter, Cosmology of the Planck era from a renormalization group for quantum gravity. Phys. Rev. D 65, 043508 (2002). arXiv:hep-th/0106133 MathSciNetADSCrossRefGoogle Scholar
  9. 9.
    M. Reuter, F. Saueressig, From big bang to asymptotic de Sitter: complete cosmologies in a quantum gravity framework. J. Cosmol. Astropart. Phys. 0509, 012 (2005). arXiv:hep-th/0507167 MathSciNetADSCrossRefGoogle Scholar
  10. 10.
    A.H. Guth, The inflationary universe: a possible solution to the horizon and flatness problems. Phys. Rev. D 23, 347 (1981) ADSCrossRefGoogle Scholar
  11. 11.
    S. Weinberg, Asymptotically safe inflation. Phys. Rev. D 81, 083535 (2010). arXiv:0911.3165 [hep-th] ADSCrossRefGoogle Scholar
  12. 12.
    S.-H.H. Tye, J. Xu, Comment on asymptotically safe inflation. Phys. Rev. D 82, 127302 (2010). arXiv:1008.4787 [hep-th] ADSCrossRefGoogle Scholar
  13. 13.
    M. Hindmarsh, I.D. Saltas, f(R) Gravity from the renormalisation group. Phys. Rev. D 86, 064029 (2012). arXiv:1203.3957 [gr-qc] ADSCrossRefGoogle Scholar
  14. 14.
    M.R. Niedermaier, Gravitational fixed points from perturbation theory. Phys. Rev. Lett. 103, 101303 (2009) ADSCrossRefGoogle Scholar
  15. 15.
    T. Clunan, M. Sasaki, Tensor ghosts in the inflationary cosmology. Class. Quantum Gravity 27, 165014 (2010). arXiv:0907.3868 [hep-th] MathSciNetADSCrossRefGoogle Scholar
  16. 16.
    N. Deruelle, M. Sasaki, Y. Sendouda, A. Youssef, Lorentz-violating vs ghost gravitons: the example of Weyl gravity. J. High Energy Phys. 1209, 009 (2012). arXiv:1202.3131 [gr-qc] ADSCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg and Società Italiana di Fisica 2013

Authors and Affiliations

  1. 1.Kavli Institute for Theoretical Physics China (KITPC), State Key Laboratory of Theoretical Physics, Institute of Theoretical PhysicsChinese Academy of ScienceBeijingPeople’s Republic of China

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