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Chiral symmetry breaking in strongly coupled QED?

Kurt Langfeld
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Abstract

The coupled system of renormalized Dyson-Schwinger equations for the electron self-energy and the photon propagator are supplied with the tree level vertex as Ansatz for the renormalized three point function. The system is investigated numerically. In the case of a massive electron, the theory is ``weakly renormalizable'', i.e.\ cutoff independent for values of the cutoff below an upper limit. In this regime of cutoff independence, the quenched approximation yields good results for the electron self-energy. In the chiral limit, a logarithmic cutoff dependence of the electron self-energy is found. The question, whether a regime of cutoff independence with a spontaneously broken chiral symmetry exists in strongly coupled QED, remains open.

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Kurt Langfeld. 1995-08-16. Chiral symmetry breaking in strongly coupled QED?. https://arxiv.org/abs/hep-ph/9508307

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