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arXiv · 1905.06735

Translational anomaly of chiral fermions in two dimensions

Pau Beltrán-Palau·Jose Navarro-Salas·Silvia Pla
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Abstract

It is well known that a quantized two-dimensional Weyl fermion coupled to gravity spoils general covariance and breaks the covariant conservation of the energy-momentum tensor. In this brief article, we point out that the quantum conservation of the momentum can also fail in flat spacetime, provided the Weyl fermion is coupled to a time-varying homogeneous electric field. This signals a quantum anomaly of the space-translation symmetry, which has not been highlighted in the literature so far.

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Pau Beltrán-Palau, Jose Navarro-Salas, Silvia Pla. 2019-05-16. Translational anomaly of chiral fermions in two dimensions. https://doi.org/10.1103/physrevd.99.105008

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