Path integral for multi-field inflation
Abstract
We develop the path integral formalism for studying cosmological perturbations in multi-field inflation, which is particularly well suited to study quantum theories with gauge symmetries such as diffeomorphism invariance. We formulate the gauge fixing conditions based on the Poisson brackets of the constraints, from which we derive two convenient gauges that are appropriate for multi-field inflation. We then adopt the in-in formalism to derive the most general expression for the power spectrum of the curvature perturbation including the corrections from the interactions of the curvature mode with other light degrees of freedom. We also discuss the contributions of the interactions to the bispectrum.
Cite
@article{arxiv.1603.03689,
title = {Path integral for multi-field inflation},
author = {Jinn-Ouk Gong and Min-Seok Seo and Gary Shiu},
journal= {arXiv preprint arXiv:1603.03689},
year = {2016}
}
Comments
(v1) 27 pages; (v2) references added and typos corrected, to appear in Journal of High Energy Physics