A Lower Bound on Neutrino Mass

TL;DR

This paper establishes a lower bound on neutrino mass (~0.4 eV/c^2) based on the impact of neutrino-mediated forces on the energy density of dense astrophysical objects, addressing theoretical concerns about neutrino properties.

Contribution

It introduces a novel lower bound on neutrino mass derived from astrophysical considerations of many-body forces in dense stellar objects.

Findings

Neutrino-mediated forces can significantly increase energy density in stars.

A minimum neutrino mass of approximately 0.4 eV/c^2 is required for physical consistency.

Discussion of recent debates on the derivation of the bound.

Abstract

The exchange of massless neutrinos between heavy fermions (e.g. $e,p,n$) gives rise to a long-range 2-body force. It is shown that the analogous many-body force can lead to an unphysically large energy density in white dwarfs and neutron stars. To reduce the energy density to a physically acceptable value, the neutrino must have a {\it minimum mass}, which is approximately $0.4\;eV/c^2$. Some recent questions relating to the derivation of this bound are also discussed.