We compute the primordial trispectrum for curvature perturbations produced during cosmic inflation in models with standard kinetic terms, when the initial quantum state is not necessarily the vacuum state. The presence of initial perturbations enhances the trispectrum amplitude for configuration in which one of the momenta, say k 3, is much smaller than the others, k 3 << k 1,2,4. For those squeezed configurations the trispectrum acquires the so-called local form, with a scale dependent amplitude that can get values of order (k 1/k 3) 2. This amplitude could be larger than the prediction of the so-called Maldacena consistency relation by a factor as large as 10 6, and could reach the sensitivity of forthcoming observations, even for single-field inflationary models. © 2012 IOP Publishing Ltd and Sissa Medialab srl.
Publication Source (Journal or Book title)
Journal of Cosmology and Astroparticle Physics
Agullo, I., Navarro-Salas, J., & Parker, L. (2012). Enhanced local-type inflationary trispectrum from a non-vacuum initial state. Journal of Cosmology and Astroparticle Physics, 2012 (5) https://doi.org/10.1088/1475-7516/2012/05/019