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arXiv · hep-th/9608058

How to treat $γ_5$

Hung Cheng·S. P. Li
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Abstract

We present a method to perform renormalized perturbation calculation in gauge theories with chiral fermions. We find it proper to focus directly on the Ward-Takahashi identities, relegating dimensional regularization into a supplementary and secondary role. We show with the example of the Abelian-Higgs theory how to handle amplitudes involving fermions, particularly how to handle the matrix $γ_5$. As a demonstration of our method of renormalization, we evaluate the radiative corrections of the triangular anomaly in the Abelian-Higgs theory with appropriate number of chiral fermions. This anomaly amplitude is calculated without any regularization and is found to vanish.

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Hung Cheng, S. P. Li. 1997-02-25. How to treat $γ_5$. https://doi.org/10.1142/s0217751x98001505

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