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Non-Compact QED_3 with N_f=1 and N_f=4

S. J. Hands·J. B. Kogut·L. Scorzato·C. G. Strouthos
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Abstract

We present numerical results for non-compact three-dimensional QED for numbers of flavors N_f=1 and N_f=4.In particular, we address the issue of whether chiral symmetry is spontaneously broken in the continuum limit, and obtain a positive answer for N_f=1, with a dimensionless condensate estimated to be beta^2 ~= O(10^-3), implying that the critical number of flavors N_fc>1. We also compare the N_f=1 and N_f=4 models by analysing the transition from strong to weak coupling behaviour using an equation of state based on a continuous phase transition. While some qualitative differences emerge, it appears difficult to determine whether N_f=4 lies above or below N_fc.

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S. J. Hands, J. B. Kogut, L. Scorzato, C. G. Strouthos. 2004-04-16. Non-Compact QED_3 with N_f=1 and N_f=4. https://doi.org/10.1103/physrevb.70.104501

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