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Grand Unification and Proton Stability Near the Peccei-Quinn Scale

Alex G. Dias·V. Pleitez
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Abstract

We show that in an $SU(2)\otimes U(1)$ model with a DSF-like invisible axion it is possible to obtain (i) the convergence of the three gauge coupling constants at an energy scale near the Peccei-Quinn scale; (ii) the correct value for $\sin^2\hatθ_W(M_Z)$; (iii) the stabilization of the proton by the cyclic $Z_{13}\otimes Z_3$ symmetries which also stabilize the axion as a solution to the strong CP problem. Concerning the convergence of the three coupling constants and the prediction of the weak mixing angle at the $Z$-peak, this model is as good as the minimal supersymmetric standard model with $μ_{\rm SUSY}=M_Z$. We also consider the standard model with six and seven Higgs doublets. The main calculations were done in the 1-loop approximation but we briefly consider the 2-loop contributions.

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Alex G. Dias, V. Pleitez. 2004-07-06. Grand Unification and Proton Stability Near the Peccei-Quinn Scale. https://doi.org/10.1103/physrevd.70.055009

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