Supergravity, $\alpha$-attractors and primordial non-Gaussianity
Abstract
We compute in detail how deviations from Einstein gravity at the inflation energy scale could appear as non-Gaussian features in the sky. To illustrate this we use multi-field attractor models in the framework of supergravity to realise inflation. We find no obvious obstacle for having choices of model's parameters that generate non-Gaussian features of the equilateral and local type at the (1) level in the non-Gaussianity parameter, thus being potentially detectable in future cosmological surveys. This non-Gaussianity has its origin in either the non-canonical kinetic term (which, in turn, is an immediate consequence of assuming an hyperbolic geometry of the moduli space), the interactions of the fields in the potential or the parameter, or a combination of these three. This opens up the exciting possibility of constraining the law of gravity at energy scales close to the Planck one.
Cite
@article{arxiv.1805.04269,
title = {Supergravity, $\alpha$-attractors and primordial non-Gaussianity},
author = {Nicola Bartolo and Domenico Matteo Bianco and Raul Jimenez and Sabino Matarrese and Licia Verde},
journal= {arXiv preprint arXiv:1805.04269},
year = {2018}
}
Comments
matches version published in JCAP; no major changes, conclusions unchanged