Squeezed primordial bispectrum from general vacuum state
Cosmology and Nongalactic Astrophysics
2015-06-12 v2 General Relativity and Quantum Cosmology
High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
We study the general relation between the power spectrum and the squeezed limit of the bispectrum of the comoving curvature perturbation produced during single-field slow-roll inflation when the initial state is a general vacuum. Assuming the scale invariance of the power spectrum, we derive a formula for the squeezed limit of the bispectrum, represented by the parameter fNL, which is not slow-roll suppressed and is found to contain a single free parameter for a given amplitude of the power spectrum. Then we derive the conditions for achieving a scale-invariant fNL, and discuss a few examples.
Keywords
Cite
@article{arxiv.1302.1271,
title = {Squeezed primordial bispectrum from general vacuum state},
author = {Jinn-Ouk Gong and Misao Sasaki},
journal= {arXiv preprint arXiv:1302.1271},
year = {2015}
}
Comments
(v1) 9 pages, 1 figure; (v2) 10 pages, more clarifications and references, to appear in Classical and Quantum Gravity