Minimal trinification

Abstract

We study the trinified model, SU(3) C × SU(3) L × SU(3) R × 3 , with the minimal Higgs sector required for symmetry breaking. There are five Higgs doublets, and gauge-coupling unification results if all five are at the weak scale, without supersymmetry. The radiative see-saw mechanism yields sub-eV neutrino masses, without the need for intermediate scales, additional Higgs fields, or higher-dimensional operators. The proton lifetime is above the experimental limits, with the decay modes p →νK + and p → µ + K 0 potentially observable. We also consider supersymmetric versions of the model, with one or two Higgs doublets at the weak scale. The radiative see-saw mechanism fails with weak-scale supersymmetry due to the nonrenormalization of the superpotential, but operates in the split-SUSY scenario.1 The supersymmetric model has been studied in Refs. [8], recently also in the context of orbifold GUTs [9]. 2 By minimal we mean a Higgs sector that contains just the fields needed to break [SU(3)]3 to the standard model.

Unification without low-energy supersymmetry

“…We begin by briefly reviewing the minimal trinified model [2,3]. The gauge bosons are assigned to the adjoint representation, the fermions to ψ…”

“…However, if we go beyond SU(5), as suggested by neutrino experiments, we do not need single-step unification. Furthermore, unification is possible without supersymmetry if we extend the Higgs sector of the SM to five or six Higgs doublets [1].In this talk, we present a viable candidate for a unified theory without (low-energy) supersymmetry [2]. Since the unification of the gauge couplings occurs at a lower scale, M U ≃ 10 14 GeV, we do not choose a simple GUT group, which would yield too rapid proton decay.…”

“…In this talk, we present a viable candidate for a unified theory without (low-energy) supersymmetry [2]. Since the unification of the gauge couplings occurs at a lower scale, M U ≃ 10 14 GeV, we do not choose a simple GUT group, which would yield too rapid proton decay.…”

Dark Matter in Minimal Trinification

“…Unfortunately N 2 , N 1 and ν are also light, with the additional inconvenience that the last two seem to pair up to form a light Dirac fermion. This is highly undesirable and can be fixed invoking radiative correction induced by cubic scalar couplings [3] [4]. Calculating the one loop contribution to mass terms for light fermions and using a seesaw mechanism the spectrum for these light neutral fields become…”

“…We are going to concentrate on one of such models, known as "trinification", introduced for the first time in 1984 by S. Glashow [1], successively studied in detail by Babu et al [2] and more recently by Willenbrock et al [3] [4]. In particular we consider the minimal formulation of the model (respect to how the SM is embedded in it), and focus on the question of Dark Matter.…”