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Missing (up) Mass, Accidental Anomalous Symmetries, and the Strong CP Problem

Tom Banks·Yosef Nir·Nathan Seiberg
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Abstract

We reconsider the massless up quark solution of the strong CP problem. We show that an anomaly free horizontal symmetry can naturally lead to a massless up quark and to a corresponding accidental anomalous symmetry. Reviewing the controversy about the phenomenological viability of $m_u=0$ we conclude that this possiblity is still open and can solve the strong CP problem. To appear in the Proceedings of The Yukawa Couplings and the Origins of Mass Workshop.

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Tom Banks, Yosef Nir, Nathan Seiberg. 1994-03-01. Missing (up) Mass, Accidental Anomalous Symmetries, and the Strong CP Problem. https://arxiv.org/abs/hep-ph/9403203

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