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arXiv · 1606.05879

Precision Predictions for the Primordial Power Spectra from f(R) Models of Inflation

D. J. Brooker·S. D. Odintsov·R. P. Woodard
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Abstract

We study the power spectra of f(R) inflation using a new technique in which the norm-squared of the mode functions is evolved. Our technique results in excellent analytic approximations for how the spectra depend upon the function $f(R)$. Although the spectra are numerically the same in the Jordan and Einstein frames for the same wave number $k$, they depend upon the geometries of these frames in quite different ways. For example, the power spectra in the two frames are different functions of the number of e-foldings until end of inflation. We discuss how future data on reheating can be used to distinguish f(R) inflation from scalar-driven inflation.

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D. J. Brooker, S. D. Odintsov, R. P. Woodard. 2016-09-07. Precision Predictions for the Primordial Power Spectra from f(R) Models of Inflation. https://doi.org/10.1016/j.nuclphysb.2016.08.010

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