Primordial bispectrum and trispectrum in multifield Dirac-Born-Infeld inflation

TL;DR

This paper introduces a multifield Dirac-Born-Infeld inflation model that produces a bispectrum combining equilateral and local shapes, and identifies a notable component of the primordial trispectrum.

Contribution

It presents a novel multifield DBI inflation model with a unique bispectrum shape and highlights a significant feature of the trispectrum.

Findings

Bispectrum combines equilateral and local shapes

Identification of a distinctive trispectrum component

Model offers new insights into primordial non-Gaussianity

Abstract

We explain the motivation and main idea of our work in reference arXiv:0907.2476 [hep-th]. We present a simple model of multifield Dirac-Born-Infeld inflation whose bispectrum exhibits a linear combination of the equilateral and local shapes, which are usually considered as separate possibilities. We also point out the presence of a particularly interesting component of the primordial trispectrum.