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arXiv · hep-ph/9306268

The Weinberg Angle Without Grand Unification

T. Moroi·Hitoshi Murayama·T. Yanagida
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Abstract

We assume that strong and electroweak interactions become strong at very high energies. With this assumption, we compute the low-energy gauge coupling constants $α_i (m_Z)$ as a function of the cutoff scale, taking the supersymmetric standard model with $3+2n$ families of quark and lepton multiplets. We find that only the five family case $(n=1)$ is consistent with the experimental values of the gauge coupling constants. This suggests the presence of a pair of families at $\sim 1$~TeV.

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T. Moroi, Hitoshi Murayama, T. Yanagida. 1993-06-12. The Weinberg Angle Without Grand Unification. https://doi.org/10.1103/physrevd.48.r2995

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