Mass freezing in growing neutrino quintessence

TL;DR

This paper explores how non-linear effects in growing neutrino quintessence lead to mass freezing within large neutrino lumps, reducing gravitational potential and stabilizing fundamental constants locally, which may reconcile cosmological and geophysical observations.

Contribution

It introduces the concept that non-linearities in the cosmon field halt neutrino mass growth in dense lumps, impacting gravitational potential and fundamental constant variations.

Findings

Neutrino lumps significantly reduce gravitational potential compared to linear models.

Mass freezing occurs in dense lumps, preventing indefinite neutrino mass increase.

Local variations of fundamental constants are much smaller than cosmological changes.

Abstract

Growing neutrino quintessence solves the coincidence problem for dark energy by a growing cosmological value of the neutrino mass which emerges from a cosmon-neutrino interaction stronger than gravity. The cosmon-mediated attraction between neutrinos induces the formation of large scale neutrino lumps in a recent cosmological epoch. We argue that the non-linearities in the cosmon field equations stop the further increase of the neutrino mass within sufficiently dense and large lumps. As a result, we find the neutrino induced gravitational potential to be substantially reduced when compared to linear extrapolations. We furthermore demonstrate that inside a lump the possible time variation of fundamental constants is much smaller than their cosmological evolution. This feature may reconcile current geophysical bounds with claimed cosmological variations of the fine structure constant.