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arXiv · hep-lat/9701016

The Three Dimensional Thirring Model for Small N_f

L. Del Debbio·S. J. Hands·J. C. Mehegan
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Abstract

We formulate the three dimensional Thirring model on a spacetime lattice and study it for various even numbers of fermion flavors N_f by Monte Carlo simulation. We find clear evidence for spontaneous chiral symmetry breaking at strong coupling, contradicting the predictions of the 1/N_f expansion. The critical point appears to correspond to an ultra-violet fixed point of the renormalisation group; a fit to a RG-inspired equation of state in the vicinity of the fixed point yields distinct critical exponents for N_f=2 and N_f=4, while no fit is found for N_f=6, suggesting there is a critical number N_fc<6 beyond which no chiral symmetry breaking occurs. The spectrum of the N_f=2 theory is studied; the states examined vary sharply but continuously across the transition.

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L. Del Debbio, S. J. Hands, J. C. Mehegan. 1997-01-30. The Three Dimensional Thirring Model for Small N_f. https://doi.org/10.1016/s0550-3213(97)00435-5

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