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Non-linear Vacuum Phenomena in Non-commutative QED

L. Alvarez-Gaume·J. L. F. Barbon
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Abstract

We show that the classic results of Schwinger on the exact propagation of particles in the background of constant field-strengths and plane waves can be readily extended to the case of non-commutative QED. It is shown that non-perturbative effects on constant backgrounds are the same as their commutative counterparts, provided the on-shell gauge invariant dynamics is referred to a non-perturbatively related space-time frame. For the case of the plane wave background, we find evidence of the effective extended nature of non-commutative particles, producing retarded and advanced effects in scattering. Besides the known `dipolar' character of non-commutative neutral particles, we find that charged particles are also effectively extended, but they behave instead as `half-dipoles'.

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L. Alvarez-Gaume, J. L. F. Barbon. 2000-06-27. Non-linear Vacuum Phenomena in Non-commutative QED. https://doi.org/10.1142/s0217751x01002750

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