Enlightening the CSL model landscape in inflation

TL;DR

This paper introduces a new CSL model extension for inflation that incorporates relativistic invariance and spacetime curvature dependence, producing a nearly scale-invariant power spectrum aligned with CMB observations.

Contribution

It presents a novel relativistic CSL model extension for inflation, linking collapse dynamics to spacetime curvature and compatible with cosmological data.

Findings

Produces a nearly scale-invariant power spectrum

Compatible with recent CMB data

Opens new avenues for CSL applications in cosmology

Abstract

We propose a novel realization for the natural extrapolation of the continuous spontaneous localization (CSL) model, in order to account for the origin of primordial inhomogeneities during inflation. This particular model is based on three main elements: (i) the semiclassical gravity framework, (ii) a collapse-generating operator associated to a relativistic invariant scalar of the energy-momentum tensor, and (iii) an extension of the CSL parameter(s) as a function of the spacetime curvature. Furthermore, employing standard cosmological perturbation theory at linear order, and for a reasonable range within the parameter space of the model, we obtain a nearly scale invariant power spectrum consistent with recent observational CMB data. This opens a vast landscape of different options for the application of the CSL model to the cosmological context, and possibly sheds light on searches for a full covariant version of the CSL theory.