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Strongly Coupled Grand Unification in Higher Dimensions

Yasunori Nomura
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Abstract

We consider the scenario where all the couplings in the theory are strong at the cut-off scale, in the context of higher dimensional grand unified field theories where the unified gauge symmetry is broken by an orbifold compactification. In this scenario, the non-calculable correction to gauge unification from unknown ultraviolet physics is naturally suppressed by the large volume of the extra dimension, and the threshold correction is dominated by a calculable contribution from Kaluza-Klein towers that gives the values for \sin^2θ_w and α_s in good agreement with low-energy data. The threshold correction is reliably estimated despite the fact that the theory is strongly coupled at the cut-off scale. A realistic 5d supersymmetric SU(5) model is presented as an example, where rapid d=6 proton decay is avoided by putting the first generation matter in the 5d bulk.

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BibTeXRIS

Yasunori Nomura. 2002-03-15. Strongly Coupled Grand Unification in Higher Dimensions. https://doi.org/10.1103/physrevd.65.085036

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