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arXiv · 1908.03750

Weyl fermions in a non-abelian gauge background and trace anomalies

Fiorenzo Bastianelli·Matteo Broccoli
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Abstract

We study the trace and chiral anomalies of Weyl fermions in a non-abelian gauge background in four dimensions. Using a Pauli-Villars regularization we identify the trace anomaly, proving that it can be cast in a gauge invariant form, even in the presence of the non-abelian chiral anomaly, that we rederive to check the consistency of our methods. In particular, we find that the trace anomaly does not contain any parity-odd topological contribution, whose presence has been debated in the recent literature.

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Fiorenzo Bastianelli, Matteo Broccoli. 2019-08-10. Weyl fermions in a non-abelian gauge background and trace anomalies. https://doi.org/10.1007/jhep10(2019)241

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