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Precision of Inflaton Potential Reconstruction from CMB Using the General Slow-Roll Approximation

Kenji Kadota·Scott Dodelson·Wayne Hu·Ewan D. Stewart
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Abstract

Through a principal component analysis, we study how accurately CMB observables can constrain inflaton potentials in a model independent manner. We apply the general slow-roll approximation in our analysis where we allow, in contrast to the standard slow-roll approximation, the possibility of variations in $V''(ϕ)$ and take into account the fact that horizon crossing is not an instantaneous event. Our analysis provides a set of modes to be used in fitting observables. We find that of order five of these modes will be constrained by future observations, so a fully general data analysis package could use the amplitudes of just a handful of modes as free parameters and retain all relevant information in the data.

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Kenji Kadota, Scott Dodelson, Wayne Hu, Ewan D. Stewart. 2005-07-13. Precision of Inflaton Potential Reconstruction from CMB Using the General Slow-Roll Approximation. https://doi.org/10.1103/physrevd.72.023510

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