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Infrared behaviour of massless QED in space-time dimensions 2 < d < 4

Indrajit Mitra·Raghunath Ratabole·H. S. Sharatchandra
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Abstract

We show that the logarithmic infrared divergences in electron self-energy and vertex function of massless QED in 2+1 dimensions can be removed at all orders of 1/N by an appropriate choice of a non-local gauge. Thus the infrared behaviour given by the leading order in 1/N is not modified by higher order corrections. Our analysis gives a computational scheme for the Amati-Testa model, resulting in a non-trivial conformal invariant field theory for all space-time dimensions 2 < d < 4.

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Indrajit Mitra, Raghunath Ratabole, H. S. Sharatchandra. 2005-03-14. Infrared behaviour of massless QED in space-time dimensions 2 < d < 4. https://doi.org/10.1016/j.physletb.2005.02.049

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