English

The MESS of the CMB

Cosmology and Nongalactic Astrophysics 2021-03-03 v1

Abstract

We analyze cosmic microwave background (CMB) data taking into account the effects of a momentum dependent effective sound speed (MESS). This approach allows to study the effects of primordial entropy in a model independent way, and its implementation requires a minimal modification of existing CMB fitting numerical codes developed for single scalar field models. We adopt a phenomenological approach, and study the effects a local variation of the MESS around the scale where other analysis have shown some deviation from an approximately scale invariant curvature perturbation spectrum. We obtain a substantial improvement of the fit with respect to a model without MESS, showing that primordial entropy modeled by MESS can be an explanation of these deviations.

Keywords

Cite

@article{arxiv.2006.03395,
  title  = {The MESS of the CMB},
  author = {Manuel Alejandro Jaramillo Rodrguez and Antonio Enea Romano and Sergio Andres Vallejo-Pena},
  journal= {arXiv preprint arXiv:2006.03395},
  year   = {2021}
}

Comments

15 pages, 5 figures

R2 v1 2026-06-23T16:05:15.320Z