Linear Scalar Perturbations in the Quasi-Static Regime

Zenodo (CERN European Organization for Nuclear Research) 2026 Preprint Open access

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Authors: Arturo Cerezo
DOI: 10.5281/zenodo.18827767
Cited by: 2

Abstract

We analyze RCD linear scalar perturbations in the quasi-static regime. The homogeneous cosmological background forces all EFT modification parameters to unity: mu = eta = Sigma = 1. RCD is indistinguishable from LCDM at linear scales, with Delta(f*sigma_8)/f*sigma_8 < 1e-6. Modifications activate only in the non-linear regime where coherence gradients become non-negligible. This linear safety is a structural consequence of the action, not a tuning.

Fields of Study & Subjects

Cosmology and Gravitation Theories Galaxies: Formation Evolution Phenomena Black Holes and Theoretical Physics

Publication details

Journal / source
Zenodo (CERN European Organization for Nuclear Research)
Publication date
1 March 2026
Language
EN
Document type
Preprint