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arXiv · hep-ph/0703017

Calculable One-Loop Contributions to S and T Parameters in the Gauge-Higgs Unification

C. S. Lim·Nobuhito Maru
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Abstract

We investigate the one-loop contributions to S and T oblique parameteres in gauge-Higgs unification. We show that these parameters are finite in five dimensional space-time, but are divergent in more than five dimensions. Remarkably, however, we find that a particular linear combination of S and T parameters, S - 4 \cos θ_{W} T, becomes finite for six dimensional space-time, though each of these parameters is divergent. This is because, in the Gauge-Higgs unification scenario, the operators relevant for S and T parameters are not independent, but are included in a unique higher dimensional gauge invariant operator. Thus the predictable linear combination is model independent, irrespectibly of the detail of the matter content.

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C. S. Lim, Nobuhito Maru. 2007-04-13. Calculable One-Loop Contributions to S and T Parameters in the Gauge-Higgs Unification. https://doi.org/10.1103/physrevd.75.115011

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