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arXiv · hep-lat/0106015

Does the XY Model have an integrable continuum limit?

J. Balog·M. Niedermaier·F. Niedermayer·A. Patrascioiu·E. Seiler·P. Weisz
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Abstract

The quantum field theory describing the massive O(2) nonlinear sigma-model is investigated through two non-perturbative constructions: The form factor bootstrap based on integrability and the lattice formulation as the XY model. The S-matrix, the spin and current two-point functions, as well as the 4-point coupling are computed and critically compared in both constructions. On the bootstrap side a new parafermionic super selection sector is found; in the lattice theory a recent prediction for the (logarithmic) decay of lattice artifacts is probed.

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J. Balog, M. Niedermaier, F. Niedermayer, A. Patrascioiu, E. Seiler, P. Weisz. 2006-12-04. Does the XY Model have an integrable continuum limit?. https://doi.org/10.1016/s0550-3213(01)00487-4

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