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arXiv · hep-lat/9511014

Non-compact Lattice QED with Two Charges: Phase Diagram and Renormalization Group Flow

A. Ali Khan
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Abstract

The phase diagram of non-compact lattice QED in four dimensions with staggered fermions of charges 1 and $-1/2$ is investigated. The renormalized charges are determined and found to be in agreement with perturbation theory. This is an indication that there is no continuum limit with non-vanishing renormalized gauge coupling, and that the theory has a validity bound for every finite value of the renormalized coupling. The renormalization group flow of the charges is investigated and an estimate for the validity bound as a function of the cut-off is obtained. Generalizing this estimate to all fermions in the Standard Model,it is found that a cut-off at the Planck scale implies that $α_R$ has to be less than $1/80$. Due to spontaneous chiral symmetry breaking, strongly bound fermion-antifermion composite states are generated. Their spectrum is discussed.

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A. Ali Khan. 1995-11-10. Non-compact Lattice QED with Two Charges: Phase Diagram and Renormalization Group Flow. https://doi.org/10.1103/physrevd.53.6416

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