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arXiv · hep-ph/0212029

Gauge Model of Quark-Lepton Nonuniversality

Xiao-Yuan Li·Ernest Ma
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Abstract

We propose a gauge model where quark-lepton universality is an accidental symmetry which is only approximate, in analogy to the well-accepted notion that strong isospin is accidental and approximate. This is a natural framework for explaining possible small deviations of quark-lepton universality which is applicable to the recently reported apparent nonunitarity of the quark mixing matrix. As a result, small departures from quark-lepton universality are expected in Z decays as well as in the recent neutrino data of the NuTeV collaboration and in future low-energy experiments. New physics is predicted at the TeV scale.

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Xiao-Yuan Li, Ernest Ma. 2002-12-02. Gauge Model of Quark-Lepton Nonuniversality. https://doi.org/10.1142/s0217732303011137

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