Transport equations for the inflationary trispectrum
Abstract
We use transport techniques to calculate the trispectrum produced in multiple-field inflationary models with canonical kinetic terms. Our method allows the time evolution of the local trispectrum parameters, tauNL and gNL, to be tracked throughout the inflationary phase. We illustrate our approach using examples. We give a simplified method to calculate the superhorizon part of the relation between field fluctuations on spatially flat hypersurfaces and the curvature perturbation on uniform density slices, and obtain its third-order part for the first time. We clarify how the 'backwards' formalism of Yokoyama et al. relates to our analysis and other recent work. We supply explicit formulae which enable each inflationary observable to be computed in any canonical model of interest, using a suitable first-order ODE solver.
Keywords
Cite
@article{arxiv.1205.0024,
title = {Transport equations for the inflationary trispectrum},
author = {Gemma J. Anderson and David J. Mulryne and David Seery},
journal= {arXiv preprint arXiv:1205.0024},
year = {2012}
}
Comments
24 pages, plus references and appendix. v2: matches version published in JCAP; typo fixed in Eq. (54)