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arXiv · hep-th/9205094

Running Gauge Couplings and Thresholds in the Type II Superstring

L. Dolan·James T. Liu
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Abstract

A distinctive feature of string unification is the possibility of unification by a non-simply-laced group. This occurs most naturally in four dimensional type~II string models where the gauge symmetry is realized by Kac-Moody algebras at different levels. We investigate the running coupling constants and the one-loop thresholds for such general models. As a specific case, we examine a $\rm SU(3)\times U(1)\times U(1)$ model and find that the threshold corrections lead to a small $6\%$ increase in the unification scale.

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L. Dolan, James T. Liu. 1992-05-26. Running Gauge Couplings and Thresholds in the Type II Superstring. https://doi.org/10.1016/0550-3213(92)90047-f

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