Naturally-Coupled Dark Sectors

TL;DR

This paper reviews a mechanism where gravity naturally couples a dark sector to the Standard Model, addressing the instability caused by dark sector interactions and exploring processes to probe such couplings.

Contribution

It introduces a gravity-based framework that predicts a naturally-coupled dark sector, offering an alternative to traditional stabilization mechanisms.

Findings

Gravity predicts the existence of a dark sector.

The mechanism neutralizes SM sensitivities to dark sector scales.

Proposed processes can probe naturally-coupled dark sectors.

Abstract

The dark sector, composed of the fields neutral under the Standard Model (SM) gauge group, can couple to the SM through the Higgs, hypercharge and neutrino portals, and pull the SM towards its scale by loop corrections. This instability, not possible to prevent in the known SM completions like supersymmetry due to their sizable couplings to the SM, calls for alternative mechanisms which can neutralize sensitivities of the SM to the dark sector scale and to the ultraviolet cutoff above it. Here we review such a mechanism in which incorporation of gravity into the SM predicts the existence of a dark sector and allows it to be naturally-coupled to the SM. We discuss and illustrate salient processes which can probe the naturally-coupled dark sectors.