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arXiv · hep-th/0006154

CPT anomaly in two-dimensional chiral U(1) gauge theories

F. R. Klinkhamer·J. Nishimura
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Abstract

The CPT anomaly, which was first seen in perturbation theory for certain four-dimensional chiral gauge theories, is also present in the exact result for a class of two-dimensional chiral U(1) gauge theories on the torus. Specifically, the chiral determinant for periodic fermion fields changes sign under a CPT transformation of the background gauge field. There is, in fact, an anomaly of Lorentz invariance, which allows for the CPT theorem to be circumvented.

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F. R. Klinkhamer, J. Nishimura. 2001-04-10. CPT anomaly in two-dimensional chiral U(1) gauge theories. https://doi.org/10.1103/physrevd.63.097701

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