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arXiv · hep-th/9503131

Discrete Anomaly and Dynamical Mass in 2+1 dimensional $U(1)_V\times U(1)_A$ Model

Deog Ki Hong
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Abstract

We note that in (2+1)-dimensional gauge theories with even number of massless fermions, there is anomalous $Z_2$ symmetry if theory is regularized in a parity-invariant way. We then consider a parity invariant $U(1)_V\times U(1)_A$ model, which induces a mutual Chern-Simons term in the effective action due to $Z_2$ anomaly. The effect of the discrete anomaly is studied in the induced spin and in the dynamical fermion mass.

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Deog Ki Hong. 1995-03-21. Discrete Anomaly and Dynamical Mass in 2+1 dimensional $U(1)_V\times U(1)_A$ Model. https://doi.org/10.1103/physrevd.52.4758

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