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arXiv · 1005.4849

Nonperturbative results for the mass dependence of the QED fermion determinant

M. P. Fry
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Abstract

The fermion determinant in four-dimensional quantum electrodynamics in the presence of O(2)XO(3) symmetric background gauge fields with a nonvanishing global chiral anomaly is considered. It is shown that the leading mass singularity of the determinant's nonperturbative part is fixed by the anomaly. It is also shown that for a large class of such fields there is at least one value of the fermion mass at which the determinant's nonperturbative part reduces to its noninteracting value.

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M. P. Fry. 2010-05-26. Nonperturbative results for the mass dependence of the QED fermion determinant. https://doi.org/10.1103/physrevd.81.107701

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