Properties of scalar perturbations generated by conformal scalar field

TL;DR

This paper explores the characteristics of scalar perturbations produced by a conformal scalar field, focusing on infrared behavior, statistical anisotropy, and non-Gaussianity, with particular attention to the trispectrum.

Contribution

It provides a detailed analysis of the infrared properties, anisotropy, and non-Gaussian features of scalar perturbations from a conformal scalar field, including explicit trispectrum expressions.

Findings

Infrared peculiarities of the model are discussed.

Statistical anisotropy is inherent in the scenario.

The bispectrum vanishes due to symmetries, and the trispectrum is explicitly derived.

Abstract

Primordial scalar perturbations may be generated when complex conformal scalar field rolls down its negative quartic potential. We begin with the discussion of peculiar infrared properties of this scenario. We then consider the statistical anisotropy inherent in the model. Finally, we discuss the non-Gaussianity of scalar perturbations. Because of symmetries, the bispectrum vanishes identically. We present a general expression for the trispectrum and give its explicit form in the folded limit.