Cosmological and Astrophysical Neutrino Mass Measurements
K. N. Abazajian, E. Calabrese, A. Cooray, F. De Bernardis, S. Dodelson, A. Friedland, G. M. Fuller, S. Hannestad, B. G. Keating, E. V. Linder, C. Lunardini, A. Melchiorri, R. Miquel, E. Pierpaoli, J. Pritchard, P. Serra, M. Takada, Y. Y. Y. Wong
TL;DR
This review addresses how cosmological and astrophysical measurements constrain the sum of neutrino masses, $\sum m_\nu$, by detailing the physical basis of each probe and summarizing current and forecasted limits. It covers the primordial CMB, CMB lensing, galaxy clustering, weak lensing, the Lyman-$\alpha$ forest, 21 cm surveys, galaxy clusters, and supernova neutrinos, highlighting both the potential and the dominant systematic challenges. The paper emphasizes the model dependence of the bounds within extensions to $\Lambda$CDM and argues that joint analyses across diverse probes are essential to break degeneracies and approach a robust detection. If future cosmological constraints converge with terrestrial measurements, it would validate the standard cosmological framework; otherwise, it would point to new physics such as dynamical dark energy, modified gravity, or novel relativistic species.
Abstract
Cosmological and astrophysical measurements provide powerful constraints on neutrino masses complementary to those from accelerators and reactors. Here we provide a guide to these different probes, for each explaining its physical basis, underlying assumptions, current and future reach.