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$θ$ Effects in Chern-Simons ${\rm QED}_{2+1}$ with a Four-Fermi Interaction

Junegone Chay·Deog Ki Hong·Taejin Lee·S. H. Park
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Abstract

We investigate the effects of the Chern-Simons coupling on the high energy behavior in the $(2+1)$-dimensional Chern-Simons QED with a four-Fermi interaction. Using the $1/N$ expansion we discuss the Chern-Simons effects on the critical four-Fermi coupling at $O(1/N)$ and the $β$ function around it. High-energy behavior of Green's functions is also discussed. By explicit calculation, we find that the radiative correction to the Chern-Simons coupling vanishes at $O(1/N)$ in the broken phase of the dynamical parity symmetry. We argue that no radiative corrections to the Chern-Simons term arise at higher orders in the $1/N$ expansion.

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Junegone Chay, Deog Ki Hong, Taejin Lee, S. H. Park. 1992-11-02. $θ$ Effects in Chern-Simons ${\rm QED}_{2+1}$ with a Four-Fermi Interaction. https://doi.org/10.1103/physrevd.48.909

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