arXiv:1107.1186 · Journal of Statistical Mechanics Theory and Experiment

Universal amplitude ratios in the Ising model in three dimensions

A Gordillo-Guerrero, R Kenna, J J Ruiz-Lorenzo

Published Sep 20, 2011• 4 citations

Abstract

We use a high-precision Monte Carlo simulation to determine the universal specific-heat amplitude ratio A + / A − in the three-dimensional Ising model via the impact angle ϕ of complex temperature zeros. We also measure the correlation-length critical exponent ν from finite-size scaling and the specific-heat exponent α through hyperscaling. Extrapolations to the thermodynamic limit yield ϕ = 59.2(1.0)°, A + / A − = 0.56(3), ν = 0.630 48(32) and α = 0.1086(10). These results are compatible with some previous estimates from a variety of sources and rule out recently conjectured exact values.

DOI: 10.1088/1742-5468/2011/09/p09019

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