Witten's mechanism in the flipped SU(5) unification

TL;DR

This paper demonstrates that Witten's loop mechanism for generating Majorana neutrino masses can be effectively applied within flipped SU(5) models, offering a simpler, testable alternative to SO(10) grand unification.

Contribution

It adapts Witten's loop mechanism to flipped SU(5), reducing tensions present in SO(10) models and proposing a realistic, testable neutrino mass generation scenario.

Findings

Witten's mechanism is compatible with flipped SU(5) models.

The approach alleviates gauge unification and neutrino mass scale tensions.

A potentially realistic and testable neutrino mass scenario is proposed.

Abstract

We argue that the Witten's loop mechanism for the right-handed Majorana neutrino mass generation identified originally in the SO(10) grand unification context can be successfully adopted to the class of the simplest flipped SU(5) models. In such a framework, the main drawback of the SO(10) prototype, in particular, the generic tension among the gauge unification constraints and the absolute neutrino mass scale is alleviated and a simple yet potentially realistic and testable scenario emerges.