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On the reliability of inflaton potential reconstruction

Edmund J. Copeland·Ian J. Grivell·Edward W. Kolb·Andrew R. Liddle
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Abstract

If primordial scalar and tensor perturbation spectra can be inferred from observations of the cosmic background radiation and large-scale structure, then one might hope to reconstruct a unique single-field inflaton potential capable of generating the observed spectra. In this paper we examine conditions under which such a potential can be reliably reconstructed. For it to be possible at all, the spectra must be well fit by a Taylor series expansion. A complete reconstruction requires a statistically-significant tensor mode to be measured in the microwave background. We find that the observational uncertainties dominate the theoretical error from use of the slow-roll approximation, and conclude that the reconstruction procedure will never insidiously lead to an irrelevant potential.

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Edmund J. Copeland, Ian J. Grivell, Edward W. Kolb, Andrew R. Liddle. 1998-02-15. On the reliability of inflaton potential reconstruction. https://doi.org/10.1103/physrevd.58.043002

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