Coupling active and sterile neutrinos in the cosmon plus seesaw framework

TL;DR

This paper explores a unified framework linking active and sterile neutrinos, the seesaw mechanism, and dark energy models, showing how neutrino masses can evolve with the universe's expansion and contribute to cosmic acceleration.

Contribution

It introduces a model connecting neutrino mass variation, the seesaw mechanism, and the generalized Chaplygin gas within the cosmon field dynamics, providing a novel integrated approach.

Findings

Neutrino masses can be dynamically linked to the cosmological scale factor.

The model naturally decouples active neutrino equations from sterile neutrino dark matter.

Mass varying particles may explain cosmic acceleration and stability issues.

Abstract

The cosmological evolution of neutrino energy densities driven by cosmon-type field equations is introduced assuming that active and sterile neutrinos are intrinsically connected by cosmon fields through the {\em seesaw} mechanism. Interpreting sterile neutrinos as dark matter adiabatically coupled with dark energy results in a natural decoupling of (active) mass varying neutrino (MaVaN) equations. Identifying the dimensionless scale of the {\em seesaw} mechanism, $m/M$, with a power of the cosmological scale factor, $a$, allows for embedding the resulting masses into the generalized Chaplygin gas (GCG) scenario for the dark sector. Without additional assumptions, our findings establish a precise connection among three distinct frameworks: the cosmon field dynamics for MaVaN's, the {\em seesaw} mechanism for dynamical mass generation and the GCG scenario. Our results also corroborate with previous assertions that mass varying particles can be the right responsible for the stability issue and for the cosmic acceleration of the universe.