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Observational constraint on the fourth derivative of the inflaton potential

C. Caprini·S. H. Hansen·M. Kunz
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Abstract

We consider the flow-equations for the 3 slow-roll parameters n_S (scalar spectral index), r (tensor to scalar ratio), and dn_S/dlnk (running of the spectral index). We show that the combination of these flow-equations with the observational bounds from cosmic microwave background and large scale structure allows one to put a lower bound on the fourth derivative of the inflationary potential, M_P^4(V''''/V) > -0.02.

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C. Caprini, S. H. Hansen, M. Kunz. 2002-10-07. Observational constraint on the fourth derivative of the inflaton potential. https://doi.org/10.1046/j.1365-8711.2003.06164.x

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