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The Problem of α_s in Supersymmetric Unified Theories

S. M. Barr
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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 $α_s$. However, agreement with the experimental value of $α_s$ can be obtained if there are relatively large negative threshold corrections to $α_s$ coming from superheavy split multiplets. It is shown that such split multiplets can arise in SO(10) without fine-tuning of parameters.

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S. M. Barr. 1998-06-01. The Problem of α_s in Supersymmetric Unified Theories. https://doi.org/10.1103/physrevd.59.015004

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