Matter instabilities in general Gauss-Bonnet gravity

Antonio De Felice, David F. Mota, Shinji Tsujikawa

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

We study the evolution of cosmological perturbations in f(G) gravity, where the Lagrangian is the sum of a Ricci scalar R and an arbitrary function f in terms of a Gauss-Bonnet term G. We derive the equations for perturbations assuming matter to be described by a perfect fluid with a constant equation of state w. We show that density perturbations in perfect fluids exhibit negative instabilities during both the radiation and the matter domination, irrespective of the form of f(G). This growth of perturbations gets stronger on smaller scales, which is difficult to be compatible with the observed galaxy spectrum unless the deviation from general relativity is very small. Thus f(G) cosmological models are effectively ruled out from this ultraviolet instability, even though they can be compatible with the late-time cosmic acceleration and local gravity constraints.

Original languageEnglish
Article number023532
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume81
Issue number2
DOIs
Publication statusPublished - 2010 Jan 29
Externally publishedYes

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'Matter instabilities in general Gauss-Bonnet gravity'. Together they form a unique fingerprint.

  • Cite this