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arXiv · 1505.01051

Phase of the fermion determinant in QED_3 using a gauge invariant lattice regularization

Nikhil Karthik·Rajamani Narayanan
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Abstract

We use canonical formalism to study the fermion determinant in different three dimensional abelian gauge field backgrounds that contain non-zero magnetic and electric flux in order to understand the non-perturbative contributions to the parity-odd and parity-even parts of the phase. We show that a certain phase associated with free fermion propagation along a closed path in a momentum torus is responsible for the parity anomaly in a background with non-zero electric flux. We consider perturbations around backgrounds with non-zero magnetic flux to understand the structure of the parity-breaking perturbative term at finite temperature and mass.

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Nikhil Karthik, Rajamani Narayanan. 2015-06-12. Phase of the fermion determinant in QED_3 using a gauge invariant lattice regularization. https://doi.org/10.1103/physrevd.92.025003

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