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Quadratic Effective Action for QED in D=2,3 Dimensions

D. Dalmazi·A. de Souza Dutra·Marcelo Hott
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Abstract

We calculate the effective action for Quantum Electrodynamics (QED) in D=2,3 dimensions at the quadratic approximation in the gauge fields. We analyse the analytic structure of the corresponding nonlocal boson propagators nonperturbatively in k/m. In two dimensions for any nonzero fermion mass, we end up with one massless pole for the gauge boson . We also calculate in D=2 the effective potential between two static charges separated by a distance L and find it to be a linearly increasing function of L in agreement with the bosonized theory (massive Sine-Gordon model). In three dimensions we find nonperturbatively in k/m one massive pole in the effective bosonic action leading to screening. Fitting the numerical results we derive a simple expression for the functional dependence of the boson mass upon the dimensionless parameter e^{2}/m .

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D. Dalmazi, A. de Souza Dutra, Marcelo Hott. 1999-12-29. Quadratic Effective Action for QED in D=2,3 Dimensions. https://doi.org/10.1103/physrevd.61.125018

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