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arXiv · 1609.08376

Lorentz symmetry violation in the fermion number anomaly with the chiral overlap operator

Hiroki Makino·Okuto Morikawa
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Abstract

Recently, Grabowska and Kaplan proposed a four-dimensional lattice formulation of chiral gauge theories on the basis of a chiral overlap operator. We compute the classical continuum limit of the fermion number anomaly in this formulation. Unexpectedly, we find that the continuum limit contains a term which is not Lorentz invariant. The term is, however, proportional to the gauge anomaly coefficient, and thus the fermion number anomaly in this lattice formulation automatically restores the Lorentz-invariant form when and only when the anomaly cancellation condition is met.

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Hiroki Makino, Okuto Morikawa. 2016-09-27. Lorentz symmetry violation in the fermion number anomaly with the chiral overlap operator. https://doi.org/10.1093/ptep/ptw183

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