Comment on "Cosmic Microwave Background Constraints Cast a Shadow On Continuous Spontaneous Localization Models"

TL;DR

This paper critiques recent claims that cosmological data rules out CSL models by highlighting the narrow scope of previous analyses and emphasizing the broad range of possible applications of CSL in cosmology.

Contribution

It demonstrates that previous conclusions are limited by specific assumptions and that many alternative CSL implementations remain compatible with observational data.

Findings

Previous constraints are based on narrow assumptions.

A wide landscape of CSL applications remains viable.

Cosmological data does not definitively exclude all CSL models.

Abstract

In a recent paper [J. Martin and V. Vennin, Phys. Rev. Lett. 124, 080402 (2020)] it was argued that, for most natural choices, the direct application of the continuous spontaneous localization (CSL) theory to the inflationary case, as it is known to work in non-relativistic laboratory situations, is ruled out by cosmological observational data, thus casting a shadow on models based on CSL theory. We point out that such results are based on the consideration of a rather narrow set of choices for the application of the theory to the cosmological context and that the landscape of open and different possibilities is extremely vast.