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Primordial trispectrum from inflation

Christian T. Byrnes·Misao Sasaki·David Wands
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Abstract

We use the delta N-formalism to describe the leading order contributions to the primordial power spectrum, bispectrum and trispectrum in multiple-field models of inflation at leading order in a perturbative expansion. In slow-roll models where the initial field fluctuations at Hubble-exit are nearly Gaussian, any detectable non-Gaussianity is expected to come from super-Hubble evolution. We show that the contribution to the primordial trispectrum can be described by two non-linearity parameters, tau_{NL} and g_{NL}, which are dependent upon the second and third derivatives of the local expansion with respect to the field values during inflation.

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Christian T. Byrnes, Misao Sasaki, David Wands. 2006-12-21. Primordial trispectrum from inflation. https://doi.org/10.1103/physrevd.74.123519

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