Standard Cosmological Evolution in a Wide Range of f(R) Models

Understand

Using techniques from singular perturbation theory, we explicitly calculate the cosmological evolution in a class of modified gravity models.

• By considering the (m)CDTT model, which aims to explain the current acceleration of the universe with a modification of gravity, we show that Einstein evolution can be recovered for most of cosmic history in at least one f(R) model.
• We show that a standard epoch of matter domination can be obtained in the mCDTT model, providing a sufficiently long epoch to satisfy observations.
• We note that the additional inverse term will not significantly alter standard evolution until today and that the solution lies well within present constraints from Big Bang Nucleosynthesis.