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arXiv · hep-th/9411016

O(1/N_f) Corrections to the Thirring Model in 2<d<4

Simon Hands
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Abstract

The Thirring model, that is, a relativistic field theory of fermions with a contact interaction between vector currents, is studied for dimensionalities 2<d<4 using the 1/N_f expansion, where N_f is the number of fermion species. The model is found to have no ultraviolet divergences at leading order provided a regularization respecting current conservation is used. Explicit O(1/N_f) corrections are computed, and the model shown to be renormalizable at this order in the massless limit; renormalizability appears to hold to all orders due to a special case of Weinberg's theorem. This implies there is a universal amplitude for four particle scattering in the asymptotic regime. Comparisons are made with both the Gross-Neveu model and QED.

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Simon Hands. 1994-11-10. O(1/N_f) Corrections to the Thirring Model in 2<d<4. https://doi.org/10.1103/physrevd.51.5816

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