Emergence of inflationary perturbations in the CSL model

TL;DR

This paper explores how the CSL model can generate primordial inflationary perturbations, providing a new approach that explains the quantum-to-classical transition and results in stable, observable power spectra.

Contribution

It introduces a novel implementation of the CSL model during inflation that directly generates perturbations and maintains consistency with observations.

Findings

Power spectra are time-independent in this framework.

The model depends on a single CSL parameter.

Results align with cosmological and laboratory data.

Abstract

The inflationary paradigm is the most successful model that explains the observed spectrum of primordial perturbations. However, the precise emergence of such inhomogeneities and the quantum-to-classical transition of the perturbations has not yet reached a consensus among the community. The Continuous Spontaneous Localization model (CSL), in the cosmological context, might be used to provide a solution to the mentioned issues by considering a dynamical reduction of the wave function. The CSL model has been applied to the inflationary universe before and different conclusions have been obtained. In this letter, we use a different approach to implement the CSL model during inflation. In particular, in addition to accounting for the quantum-to-classical transition, we use the CSL model to generate the primordial perturbations, that is, the dynamical evolution provided by the CSL model is responsible for the transition from a homogeneous and isotropic initial state to a final one lacking such symmetries. Our approach leads to results that can be clearly distinguished from preceding works. Specifically, the scalar and tensor power spectra are not time-dependent, and retains the amplification mechanism of the CSL model. Moreover, our framework depends only on one parameter (the CSL parameter) and its value is consistent with cosmological and laboratory observations.