The Problem of \alpha_s in Supersymmetric Unified Theories

Abstract

It is shown that in SO(10) there is a general connection between the suppression of higgsino mediated proton decay and the value of ${\alpha }_s$. However, agreement with the experimental value of ${\alpha }_s$ can be obtained if there are relatively large negative threshold corrections to ${\alpha }_s$ coming from superheavy split multiplets. It is shown that such split multiplets can arise in SO(10) without fine-tuning of parameters.

Comments: 14 pages LaTex, no figures