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Discontinuous behavior of perturbative Yang-Mills theories in the limit of dimensions D->2

A. Bassetto·R. Begliuomini·G. Nardelli
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Abstract

We calculate in dimensions $D=2+ε$ and in light-cone gauge (LCG) the perturbative ${\cal O}(g^4)$ contribution to a rectangular Wilson loop in the (t,x)-plane coming from diagrams with a self-energy correction in the vector propagator. In the limit $ε\to 0$ the result is finite, in spite of the vanishing of the triple vector vertex in LCG, and provides the expected agreement with the analogous calculation in Feynman gauge.

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A. Bassetto, R. Begliuomini, G. Nardelli. 1999-04-08. Discontinuous behavior of perturbative Yang-Mills theories in the limit of dimensions D->2. https://doi.org/10.1103/physrevd.59.125005

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