General Relativity and Gravitation

, Volume 27, Issue 12, pp 1309–1321 | Cite as

Almost-homogeneity of the universe in higher-order gravity

  • David R. Taylor
  • Roy Maartens


In the R+αR2 gravity theory, we show that if freely propagating massless particles have an almost isotropic distribution, then the spacetime is almost Friedmann-Robertson-Walker (frw). This extends the result proved recently in general relativity (α = 0), which is applicable to the microwave background after photon decoupling. The higher-order result is in principle applicable to a massless species that decouples in the early universe, such as a relic graviton background. Any future observations that show small anisotropies in such a background would imply that the geometry of the early universe were almostfrw.


Microwave Anisotropy General Relativity Differential Geometry Early Universe 
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Copyright information

© Plenum Publishing Corporation 1995

Authors and Affiliations

  • David R. Taylor
    • 1
    • 2
  • Roy Maartens
    • 2
    • 3
  1. 1.Department of Computational and Applied MathematicsWitwatersrand UniversitySouth Africa
  2. 2.School of MathematicsPortsmouth UniversityEngland
  3. 3.Centre for Nonlinear StudiesWitwatersrand UniversitySouth Africa

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