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arXiv · 2203.11668

Chiral fermions, dimensional regularization, and the trace anomaly

Fiorenzo Bastianelli·Luca Chiese
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Abstract

We investigate the trace anomaly of a chiral fermion in dimensional regularization, considering in detail the simplest case of coupling to an abelian gauge field. We apply the Breitenlohner-Maison/'t Hooft-Veltman prescription for dealing with the chiral matrix $\gamma^5$ and verify that no parity-odd term arises in the trace anomaly. The issue treated here is analogous to that of a chiral fermion in curved spacetime, discussed in recent literature. The advantage of having a simplified background minimizes the amount of algebraic calculations and allows pinpointing better the subtle points carried by dimensional regularization.

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Fiorenzo Bastianelli, Luca Chiese. 2022-03-22. Chiral fermions, dimensional regularization, and the trace anomaly. https://doi.org/10.1016/j.nuclphysb.2022.115914

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