Dark Matter from Holography

TL;DR

This paper proposes a holographic model for dark matter derived from the universe's horizon scale, explaining dark matter and the baryon-dark matter coincidence without particle physics.

Contribution

It introduces a holographic dark matter model using Ricci cutoff, linking dark matter to horizon scale and addressing vacuum energy sign issues.

Findings

Accounts for dark matter using holography and Ricci cutoff.

Explains baryon-dark matter density coincidence.

Reverses vacuum energy sign to match observations.

Abstract

Previous studies have examined the holographic principle as a means of producing dark energy. Here we propose instead the possibility of holographic dark matter. In this case, dark matter does not arise in the framework of particle physics but is derived from the infrared cutoff set by the horizon scale. Using the Ricci cutoff, and a universe containing only baryons and radiation, we can account for the dark matter and naturally explain the coincidence between baryonic and nonbaryonic contributions to the density. In the presence of a pre-existing vacuum energy density our model reverses the sign of this density, thus accounting for the fact that certain string theories generically predict a negative vacuum energy, but observations require a positive value.