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arXiv · hep-ph/9512243

Self Consistent $1/N_c$ Expansion In The Presence Of Electroweak Interactions

Chi-Keung Chow·Tung-Mow Yan
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Abstract

In the conventional approach to the $1/N_c$ expansion, electroweak interactions are switched off and large $N_c$ QCD is treated in isolation. We study the self-consistency of taking the large $N_c$ limit in the presence of electroweak interaction. If the electroweak coupling constants are held constant, the large $N_c$ counting rules are violated by processes involving internal photon or weak boson lines. Anomaly cancellations, however, fix the ratio of electric charges of different fermions. This allows a self-consistent way to scale down the electronic charge $e$ in the large $N_c$ limit and hence restoring the validity of the large $N_c$ counting rules.

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Chi-Keung Chow, Tung-Mow Yan. 1995-12-05. Self Consistent $1/N_c$ Expansion In The Presence Of Electroweak Interactions. https://doi.org/10.1103/physrevd.53.5105

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