# A minimal non-supersymmetric SO(10) model with Peccei--Quinn symmetry

## TL;DR

This paper proposes a minimal non-supersymmetric SO(10) grand unified theory that achieves gauge coupling unification, predicts observable proton decay, stabilizes the electroweak vacuum, and includes axion dark matter.

## Contribution

It introduces a minimal SO(10) model with specific scalars that unify couplings, predict proton decay within experimental reach, and address vacuum stability and dark matter.

## Key findings

- Gauge coupling unification achieved with two color-octet scalars.
- Proton lifetime predicted below current experimental bounds.
- Model reproduces Standard Model observables and predicts neutrino parameters.

## Abstract

We present a minimal non-supersymmetric SO(10) GUT breaking directly to the Standard Model gauge group. Precise gauge coupling unification is achieved due to the presence of two color-octet scalars, one of which is accessible to LHC searches. Proton lifetime is predicted to be below $4.5\times 10^{34}$ years, which is within the projected five-year sensitivity of the proposed Hyper-Kamiokande experiment. We find that the Standard Model observables are reproduced to a reasonable accuracy in a numerical fit, which also predicts the unknown neutrino parameters. Finally, the two scalar representations stabilize the electroweak vacuum and the dark matter is comprised of axions.