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Polychromatic Grand Unification

G. C. Branco·J. -M. Gerard·R. Gonzalez Felipe·B. M. Nobre
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Abstract

The possibility of achieving a gauge coupling grand unification by increasing the QCD degrees of freedom at higher energies is investigated. When confronted with precision low-energy data, the generic weak-mixing angle relation sin^2(theta_W) = N/2(N+1) requires N=7 colors at the GUT scale M_U ~ 10^17 GeV. With the exclusive addition of light Higgs doublets to the standard model particle content, such a unification may also occur if N=5 at M_U ~ 10^16 GeV.

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G. C. Branco, J. -M. Gerard, R. Gonzalez Felipe, B. M. Nobre. 2003-05-08. Polychromatic Grand Unification. https://arxiv.org/abs/hep-ph/0305092

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