What Is Half a Neutrino? Reviewing Cosmological Constraints on Neutrinos and Dark Radiation

2013/01/01 by Signe Riemer–Sørensen, Signe Riemer-Sørensen, David Parkinson +2
Physics and Astronomy · #Astrophysics #Cosmology #Cosmology and Gravitation Theories #Dark energy #Dark matter #Lambda-CDM model #Massless particle #Neutrino #Neutrino Physics Research #Particle physics #Particle physics theoretical and experimental studies #Physics #Physics beyond the Standard Model #Standard Model (mathematical formulation) #Theoretical physics #astro-ph.CO #hep-ph

paper · pdf · doi:10.1017/pas.2013.005

15 pages, 4 figures, invited review accepted for publication in PASA

openalex publication_date 2013/01/01 · arxiv created 2013/01/29 · arxiv updated 2015/06/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Abstract Neutrinos are one of the major puzzles in modern physics. Despite measurements of mass differences, the Standard Model of particle physics describes them as exactly massless. Additionally, recent measurements from both particle physics experiments and cosmology indicate the existence of more than the three Standard Model species. Here, we review the cosmological evidence and its possible interpretations.

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