DESI and the Hubble tension in light of modified recombination

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Lynch, Gabriel P., Knox, Lloyd, Chluba, Jens
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866929386741039104
author Lynch, Gabriel P.
Knox, Lloyd
Chluba, Jens
author_facet Lynch, Gabriel P.
Knox, Lloyd
Chluba, Jens
contents Recent measurements and analyses from the Dark Energy Spectroscopic Instrument (DESI) Collaboration and supernova surveys combined with cosmic microwave background (CMB) observations, indicate that the dark energy density changes over time. Here we explore the possibility that the dark energy density is constant, but that the cosmological recombination history differs substantially from that in $Λ$CDM. When we free up the ionization history, but otherwise assume the standard cosmological model, we find the combination of CMB and DESI data prefer i) early recombination qualitatively similar to models with small-scale clumping, ii) a value of $H_0$ consistent with the estimate from the SH0ES Collaboration at the $2σ$ level, and iii) a higher CMB lensing power, which takes pressure off of otherwise tight constraints on the sum of neutrino masses. Our work provides additional motivation for finding physical models that lead to the small-scale clumping that can theoretically explain the ionization history preferred by DESI and CMB data.
format Preprint
id arxiv_https___arxiv_org_abs_2406_10202
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle DESI and the Hubble tension in light of modified recombination
Lynch, Gabriel P.
Knox, Lloyd
Chluba, Jens
Cosmology and Nongalactic Astrophysics
Recent measurements and analyses from the Dark Energy Spectroscopic Instrument (DESI) Collaboration and supernova surveys combined with cosmic microwave background (CMB) observations, indicate that the dark energy density changes over time. Here we explore the possibility that the dark energy density is constant, but that the cosmological recombination history differs substantially from that in $Λ$CDM. When we free up the ionization history, but otherwise assume the standard cosmological model, we find the combination of CMB and DESI data prefer i) early recombination qualitatively similar to models with small-scale clumping, ii) a value of $H_0$ consistent with the estimate from the SH0ES Collaboration at the $2σ$ level, and iii) a higher CMB lensing power, which takes pressure off of otherwise tight constraints on the sum of neutrino masses. Our work provides additional motivation for finding physical models that lead to the small-scale clumping that can theoretically explain the ionization history preferred by DESI and CMB data.
title DESI and the Hubble tension in light of modified recombination
topic Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2406.10202