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QED in a Strong External Magnetic Field: Beyond the Constant Mass Approximation

J. Alexandre·K. Farakos·G. Koutsoumbas
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Abstract

We solve the Schwinger-Dyson equations for QED in 2+1 or 3+1 dimensions in the presence of a strong homogeneous external magnetic field. The magnetic field is assumed strong enough, so that the lowest Landau level approximation holds, but the usual assumption of a momentum-independent self-energy is not made. In 2+1 dimensions, the scaling with logarithm changes to a square root dependence on the magnetic field, but the most spectacular result takes place in 3+1 dimensions, where the constant mass approximation turns out to be unreliable and the (momentum-dependent) dynamical mass is larger by several orders of magnitude compared to what has been found till now using the constant mass approximation.

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J. Alexandre, K. Farakos, G. Koutsoumbas. 2000-05-12. QED in a Strong External Magnetic Field: Beyond the Constant Mass Approximation. https://doi.org/10.1103/physrevd.62.105017

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