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Primordial non-gaussianities from multiple-field inflation

David Seery·James E. Lidsey
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Abstract

We calculate the three-point correlation function evaluated at horizon crossing for a set of interacting scalar fields coupled to gravity during inflation. This provides the initial condition for the three-point function of the curvature perturbation in the Sasaki--Stewart δN formulation. We find that the effect is small, of the order of a slow-roll parameter, and that the non-gaussianity can be determined on large scales once the unperturbed background evolution is known. As an example of the use of our formalism, we calculate the primordial non-gaussianity arising in a model of assisted inflation.

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David Seery, James E. Lidsey. 2005-09-21. Primordial non-gaussianities from multiple-field inflation. https://doi.org/10.1088/1475-7516%2F2005%2F09%2F011

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