$SO(10) \to SU(5) \times U(1)_\chi$ as the Origin of Dark Matter

TL;DR

This paper explores how breaking $SO(10)$ to $SU(5) imes U(1)_ ext{chi}$ naturally leads to gauge unification and predicts dark matter candidates, linking the dark sector to grand unification.

Contribution

It introduces specific particle additions that achieve gauge unification and automatically generate dark matter within a grand unified framework.

Findings

Gauge coupling unification achieved with added particles.

Dark matter candidates emerge naturally with a defined parity.

$U(1)_ ext{chi}$ may underlie the dark sector symmetry.

Abstract

In the decomposition of $SO(10)$ grand unification to $SU(5) \times U(1)_\chi$, two desirable features are obtained with the addition of one colored fermion octet $\Omega$, one electroweak fermion triplet $\Sigma$ and one complex scalar triplet $S$ to the particle content of the standard model with two Higgs doublets. They are (1) gauge coupling unification of $SU(3)_C \times SU(2)_L \times U(1)_Y$ to $SU(5)$, and (2) the automatic (predestined) emergence of dark matter, i.e. $\Omega$, $\Sigma$ and $S$, with dark parity given by $(-1)^{Q_\chi + 2j}$. It suggests that $U(1)_\chi$ may well be the underlying symmetry of the dark sector.