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Unexpected results in asymptotically free quantum field theories

Peter Hasenfratz·Ferenc Niedermayer
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Abstract

We study the behavior of asymptotically free (AF) spin and gauge models when their continuous symmetry group is replaced by different discrete non-Abelian subgroups. Precise numerical results with relative errors down to O(0.1%) suggest that the models with large subgroups are in the universality class of the underlying original models. We argue that such a scenario is consistent with the known properties of AF theories. The small statistical errors allow a detailed investigation of the cut-off effects also. At least up to correlation lengths ~300 they follow effectively an O(a) rather than the expected O(a^2) form both in the O(3) and in the dodecahedron model.

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Peter Hasenfratz, Ferenc Niedermayer. 2000-07-07. Unexpected results in asymptotically free quantum field theories. https://doi.org/10.1016/s0550-3213(00)00696-9

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