Do data favor neutrino mass and a coupling between Cold Dark Matter and Dark Energy?

TL;DR

This study explores how allowing for a coupling between Cold Dark Matter and Dark Energy, along with non-zero neutrino masses, can improve the fit to cosmological data, suggesting both may be slightly favored.

Contribution

It introduces a combined analysis of CDM-DE coupling and neutrino masses using MCMC, showing these factors are slightly preferred over models without them.

Findings

Significant CDM-DE coupling is slightly favored.

Non-zero neutrino masses improve the fit.

Best fit: coupling ~1/2 m_p, neutrino mass ~0.12 eV per flavor.

Abstract

We allow simultaneously for a CDM--DE coupling and non--zero neutrino masses and find that significant coupling and neutrino mass are (slightly) statistically favoured in respect to a cosmology with no coupling and negligible neutrino mass (our best fits are: C~1/2m_p, m_\nu~0.12eV each flavor). We assume DE to be a self--interacting scalar field and use a standard Monte Carlo Markov Chain approach.