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arXiv · hep-lat/9607029

The Spectrum of the 2+1 Dimensional Gauge Ising Model

V. Agostini·G. Carlino·M. Caselle·M. Hasenbusch
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Abstract

We present a high precision Monte Carlo study of the spectrum of the $Z_2$ gauge theory in $2+1$ dimensions in the strong coupling phase. Using state of the art Monte Carlo techniques we are able to accurately determine up to three masses in a single channel. We compare our results with the strong coupling expansion for the lightest mass and with results for the universal ratio $σ/m^2$ determined for the $ϕ^4$-theory. Finally the whole spectrum is compared with that obtained from the Isgur-Paton flux tube model and the spectrum of the $2+1$ dimensional $SU(2)$ gauge theory. A remarkable agreement between the Ising and SU(2) spectra (except for the lowest mass state) is found.

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V. Agostini, G. Carlino, M. Caselle, M. Hasenbusch. 1996-07-11. The Spectrum of the 2+1 Dimensional Gauge Ising Model. https://doi.org/10.1016/s0550-3213(96)00539-1

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