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On the origin of divergences in massless $QED_2$

Rodolfo Casana·Sebastiao Alves Dias
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Abstract

We show that ultraviolet divergences found in fermionic Green's functions of massless $QED_2$ have an essentially non-perturbative nature. We investigate their origin both in gauge invariant formalism (the one where we introduce Wess-Zumino fields to restore quantum gauge invariance) and in gauge non-invariant formalism, mapping two different but equivalent mechanisms responsible for their appearance. We find the same results in both approaches, what contradicts a previous work of Jian-Ge, Qing-Hai and Yao-Yang, that found no divergences in the chiral Schwinger model considered in the gauge invariant formalism.

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Rodolfo Casana, Sebastiao Alves Dias. 2001-06-06. On the origin of divergences in massless $QED_2$. https://doi.org/10.1088/0954-3899%2F27%2F7%2F310

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