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arXiv · hep-lat/9509033

Comparison between Theoretical Four-Loop Predictions and Monte Carlo Calculations in the Two-Dimensional $N$-Vector Model for $N=3,4,8$

Sergio Caracciolo·Robert G. Edwards·Tereza Mendes·Andrea Pelissetto·Alan D. Sokal
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Abstract

We have computed the four-loop contribution to the beta-function and to the anomalous dimension of the field for the two-dimensional lattice $N$-vector model. This allows the determination of the second perturbative correction to various long-distance quantities like the correlation lengths and the susceptibilities. We compare these predictions with new Monte Carlo data for $N = 3,4,8$. From these data we also extract the values of various universal nonperturbative constants, which we compare with the predictions of the $1/N$ expansion.

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Sergio Caracciolo, Robert G. Edwards, Tereza Mendes, Andrea Pelissetto, Alan D. Sokal. 1995-09-12. Comparison between Theoretical Four-Loop Predictions and Monte Carlo Calculations in the Two-Dimensional $N$-Vector Model for $N=3,4,8$. https://doi.org/10.1016/0920-5632(96)00169-7

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