A Dynamical Explanation of the Dark Matter-Baryon Coincidence

TL;DR

This paper proposes a dynamical mechanism involving a scalar field that adjusts dark matter and baryon masses to explain their near-equal energy densities, independent of their microscopic nature.

Contribution

It introduces a new scalar-based mechanism that dynamically explains the dark matter-baryon coincidence without relying on specific dark matter models.

Findings

Scalar field adjusts masses to match energy densities

Predicts new force and density-dependent proton mass

Provides a universal explanation for the coincidence

Abstract

The near equality of the dark matter and baryon energy densities is a remarkable coincidence, especially when one realizes that the baryon mass is exponentially sensitive to UV parameters in the form of dimensional transmutation. We explore a new dynamical mechanism, where in the presence of an arbitrary number density of baryons and dark matter, a scalar adjusts the masses of dark matter and baryons until the two energy densities are comparable. In this manner, the coincidence is explained regardless of the microscopic identity of dark matter and how it was produced. This new scalar causes a variety of experimental effects such as a new force and a (dark) matter density-dependent proton mass.