Suppressed SUSY for the SU(5) Grand Unified Supergravity Theory

Abstract

This paper starts with the most basic SU(5) Grand Unified Theory, coupled to Supergravity. Then it builds a new theory, incorporating the ideas of Suppressed SUSY. Suppressed SUSY is an alternative to the spontaneous breaking of SUSY. It does not need an invisible sector or explicit soft breaking of SUSY. It varies the content of the supermultiplets while keeping the restrictive nature of SUSY. For the simple model and sector constructed here, Suppressed SUSY has only three dimensionless parameters, plus the Planck mass. At tree level, this predicts a set of 8 different new masses, along with a cosmological constant that is naturally zero. The X and Y vector bosons get Planck scale masses $2 \sqrt{10} g_5 M_{\rm P}$. The five scalar multiplets that accompany the Higgs, and the Gravitino, all get colossally huge `SuperPlanck' scale masses of order $M_{\rm SP} \approx 10^{17} M_{\rm P}$ from a see-saw mechanism that arises from the theory. This new mass spectrum, the well-known $SU(5)$ weak angle problem, and the cosmological constant value, should serve as guides for further modifications for the new Action.