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arXiv · hep-ph/9904303

Grand-Unification Scale Generation through the Anomalous U(1) Breaking

K. -I. Izawa·Kiichi Kurosawa·Yasunori Nomura·T. Yanagida
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Abstract

We discuss the anomalous U(1) gauge symmetry as a mechanism of generating the grand-unification scale. We conclude that unification to a simple group cannot be realized unless some parameters are ``tuned'', and that models with product gauge groups are preferred. We consider the ``R-invariant natural unification'' model with gauge groups SU(5)_{GUT} \times U(3)_H. In this model the doublet-triplet splitting problem is solved and the unwanted GUT relation m_s = m_μis avoided maintaining m_b = m_τ. Moreover, R-invariance suppresses the dangerous proton decays induced by dimension four and five operators.

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K. -I. Izawa, Kiichi Kurosawa, Yasunori Nomura, T. Yanagida. 1999-09-27. Grand-Unification Scale Generation through the Anomalous U(1) Breaking. https://doi.org/10.1103/physrevd.60.115016

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