Saved in:
Bibliographic Details
Main Authors: Kumar, Jason, Sandick, Pearl, Xu, Shuting
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2512.14672
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909965640269824
author Kumar, Jason
Sandick, Pearl
Xu, Shuting
author_facet Kumar, Jason
Sandick, Pearl
Xu, Shuting
contents We consider the effect of Light (but Massive) Relics (LiMRs) on the clustering of matter in the early Universe. We account for the fact that LiMRs which are massive enough may cluster on large length scales at early times, and may thus impact weak lensing of the cosmic microwave background (CMB) even on small angular scales. In particular, we find that LiMRs in the $\gtrsim$ eV mass range (and even $> 10$ eV), can constitute a non-negligible component of dark matter. This opens up a class of scenarios in which energy is injected as dark radiation, but begins to redshift as matter before recombination, thus avoiding constraints on $ΔN_{eff}$ while providing an eV-range dark matter component.
format Preprint
id arxiv_https___arxiv_org_abs_2512_14672
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Clustering with Light (but Massive) Relics
Kumar, Jason
Sandick, Pearl
Xu, Shuting
Cosmology and Nongalactic Astrophysics
We consider the effect of Light (but Massive) Relics (LiMRs) on the clustering of matter in the early Universe. We account for the fact that LiMRs which are massive enough may cluster on large length scales at early times, and may thus impact weak lensing of the cosmic microwave background (CMB) even on small angular scales. In particular, we find that LiMRs in the $\gtrsim$ eV mass range (and even $> 10$ eV), can constitute a non-negligible component of dark matter. This opens up a class of scenarios in which energy is injected as dark radiation, but begins to redshift as matter before recombination, thus avoiding constraints on $ΔN_{eff}$ while providing an eV-range dark matter component.
title Clustering with Light (but Massive) Relics
topic Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2512.14672