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arXiv · hep-th/9904046

Non-linear Dynamics in QED_3 and Non-trivial Infrared Structure

N. E. Mavromatos·J. Papavassiliou
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Abstract

In this work we consider a coupled system of Schwinger-Dyson equations for self-energy and vertex functions in QED_3. Using the concept of a semi-amputated vertex function, we manage to decouple the vertex equation and transform it in the infrared into a non-linear differential equation of Emden-Fowler type. Its solution suggests the following picture: in the absence of infrared cut-offs there is only a trivial infrared fixed-point structure in the theory. However, the presence of masses, for either fermions or photons, changes the situation drastically, leading to a mass-dependent non-trivial infrared fixed point. In this picture a dynamical mass for the fermions is found to be generated consistently. The non-linearity of the equations gives rise to highly non-trivial constraints among the mass and effective (`running') gauge coupling, which impose lower and upper bounds on the latter for dynamical mass generation to occur. Possible implications of this to the theory of high-temperature superconductivity are briefly discussed.

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N. E. Mavromatos, J. Papavassiliou. 1999-05-03. Non-linear Dynamics in QED_3 and Non-trivial Infrared Structure. https://doi.org/10.1103/physrevd.60.125008

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